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Sample records for systemic hemodynamic derangement

  1. Splanchnic and systemic hemodynamic derangement in decompensated cirrhosis

    DEFF Research Database (Denmark)

    Møller, Søren; Bendtsen, Flemming; Henriksen, Jens Henrik

    2001-01-01

    Patients with cirrhosis and portal hypertension exhibit characteristic hemodynamic changes with hyperkinetic systemic circulation, abnormal distribution of blood volume and neurohumoral dysregulation. Their plasma and noncentral blood volumes are increased. Splanchnic vasodilation is of pathogenic...... significance to the low systemic vascular resistance and abnormal volume distribution of blood, which are important elements in the development of the concomitant cardiac dysfunction, recently termed 'cirrhotic cardiomyopathy'. Systolic and diastolic functions are impaired with direct relation to the degree...... of liver dysfunction. Significant pathophysiological mechanisms are reduced beta-adrenergic receptor signal transduction, defective cardiac excitation-contraction coupling and conductance abnormalities. Vasodilators such as nitric oxide and calcitonin gene-related peptide are among the candidates...

  2. Splanchnic and systemic hemodynamic derangement in decompensated cirrhosis

    DEFF Research Database (Denmark)

    Møller, S; Bendtsen, F; Henriksen, Jens Henrik Sahl

    2001-01-01

    significance to the low systemic vascular resistance and abnormal volume distribution of blood, which are important elements in the development of the concomitant cardiac dysfunction, recently termed 'cirrhotic cardiomyopathy'. Systolic and diastolic functions are impaired with direct relation to the degree...... of liver dysfunction. Significant pathophysiological mechanisms are reduced beta-adrenergic receptor signal transduction, defective cardiac excitation-contraction coupling and conductance abnormalities. Vasodilators such as nitric oxide and calcitonin gene-related peptide are among the candidates...

  3. Myocardial injury in patients with hemodynamic derangements during and/or after liver transplantation.

    Science.gov (United States)

    Huang, Shun; Apinyachon, Worapot; Agopian, Vatche G; Wray, Christopher L; Busuttil, Ronald W; Steadman, Randolph H; Xia, Victor W

    2016-12-01

    Myocardial injury, defined as an elevation of cardiac troponin (cTn) resulting from ischemia, is associated with substantial mortality in surgical patients, and its incidence, risk factors, and impact on patients undergoing liver transplantation (LT) are poorly understood. In this study, adult patients who experienced perioperative hemodynamic derangements and had cTn measurements within 30 days after LT between 2006 and 2013 were studied. Of 502 patients, 203 (40.4%) met the diagnostic criteria (cTn I ≥0.1 ng/mL) of myocardial injury. The majority of myocardial injury occurred within the first three postoperative days and presented without clinical signs or symptoms of myocardial infarction. Thirty-day mortality in patients with myocardial injury was 11.4%, significantly higher compared with that in patients without myocardial injury (3.4%, P<.01). Cox analysis indicated the peak cTn was significantly associated with 30-day mortality. Multivariable logistic analysis identified three independent risk factors: requirement of ventilation before transplant (odds ratios (OR) 1.6, P=.006), RBC≥15 units (OR 1.7, P=.006), and the presence of PRS (OR 2.0, P=.028). We concluded that post-LT myocardial injury in this high-risk population was common and associated with mortality. Our findings may be used in pretransplant stratification. Further studies to investigate this postoperative cardiac complication in all LT patients are warranted. © 2016 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

  4. Early induction of direct hemoperfusion with a polymyxin-B immobilized column is associated with amelioration of hemodynamic derangement and mortality in patients with septic shock.

    Science.gov (United States)

    Chihara, Shinya; Masuda, Yoshiki; Tatsumi, Hiroomi; Nakano, Kota; Shimada, Tomokazu; Murohashi, Takao; Yamakage, Michiaki

    2017-03-01

    This study was conducted to clarify the effectiveness of induction timing of direct hemoperfusion with a polymyxin-B immobilized column (PMX-DHP) for amelioration of hemodynamic derangement and outcome in patients with septic shock. Suspected Gram-negative septic shock patients who received PMX-DHP therapy from January 2010 to December 2014 in our ICU were enrolled in this study. The patients were divided into two groups that received PMX-DHP therapy within 8 h (early group) and more than 8 h (late group) from catecholamine administration. Changes in catecholamine dose [catecholamine index (CAI)], catecholamine dose/mean arterial pressure [catecholamine index pressure (CAIP)], PaO 2 /FiO 2 and PEEP level were determined at the start of and 24 h after the start of PMX-DHP therapy. Ventilator-free days (VFD), ICU-free days (IFD), 28-day and hospital mortality were also determined. There were no significant differences in patients' characteristics between the two groups. CAI and CAIP were significantly decreased in the early group. PaO 2 /FiO 2 was not changed whereas PEEP level in the early group was significantly decreased during PMX-DHP therapy. IFD and VFD were not different in the two groups. Mortality at 28 days was significantly improved in the early group. Endotoxin acts as an early mediator in sepsis patients with suspected Gram-negative infection. Earlier induction of PMX-DHP therapy as in our study is closely associated with earlier weaning from hemodynamic derangement and with improvement of mortality. Therefore, early induction of PMX-DHP therapy is recommended for the treatment of septic shock in patients with presumed Gram-negative infection.

  5. Delineating the deranged immune system in the antiphospholipid syndrome

    NARCIS (Netherlands)

    van den Hoogen, Lucas L.; van Roon, Joël A G; Radstake, Timothy R D J; Fritsch-Stork, Ruth D E; Derksen, Ronald H W M

    2016-01-01

    The antiphospholipid syndrome (APS) is a systemic autoimmune disease that is characterized serologically by the presence of antiphospholipid antibodies (aPL) and clinically by vascular thrombosis and obstetric complications. The protein β2 glycoprotein I (β2GPI) is identified as the most important

  6. Homocysteine deteriorates intrahepatic derangement and portal-systemic collaterals in cirrhotic rats.

    Science.gov (United States)

    Tung, Hung-Chun; Hsu, Shao-Jung; Tsai, Ming-Hung; Lin, Te-Yueh; Hsin, I-Fang; Huo, Te-Ia; Lee, Fa-Yauh; Huang, Hui-Chun; Ho, Hsin-Ling; Lin, Han-Chieh; Lee, Shou-Dong

    2017-01-01

    In liver cirrhosis, the altered levels of vasoactive substances, especially endothelin-1 (ET-1) and nitric oxide (NO) lead to elevated intrahepatic resistance, increased portal-systemic collaterals and abnormal intra- and extra-hepatic vascular responsiveness. These derangements aggravate portal hypertension-related complications such as gastro-oesophageal variceal bleeding. Homocysteine, a substance implicated in cardiovascular diseases, has been found with influences on vasoresponsiveness and angiogenesis. However, their relevant effects in liver cirrhosis have not been investigated. In the present study, liver cirrhosis was induced by common bile duct ligation (BDL) in Sprague-Dawley rats. In acute study, the results showed that homocysteine enhanced hepatic vasoconstriction to ET-1 but decreased portal-systemic collateral vasocontractility to arginine vasopressin (AVP). Homocysteine down-regulated hepatic phosphorylated endothelial NO synthase (p-eNOS) and p-Akt protein expressions. Inducible NOS (iNOS) and cyclooxygenase (COX)-2 expressions were up-regulated by homocysteine in splenorenal shunt (SRS), the most prominent intra-abdominal collateral vessel. In chronic study, BDL or thioacetamide (TAA) rats received homocysteine or vehicle for 14 days. The results revealed that homocysteine increased hepatic collagen fibre deposition and fibrotic factors expressions in both BDL- and TAA-induced liver fibrotic rats. Portal-systemic shunting and expressions of mesenteric angiogenetic factors [vascular endothelial growth factor (VEGF), platelet-derived growth factor (PDGF), PDGF receptor β (PDGFRβ) and p-eNOS] were also increased in BDL rats. In conclusion, homocysteine is harmful to vascular derangements and liver fibrosis in cirrhosis. © 2016 The Author(s). published by Portland Press Limited on behalf of the Biochemical Society.

  7. Circadian profile of systemic hemodynamics

    NARCIS (Netherlands)

    Veerman, D. P.; Imholz, B. P.; Wieling, W.; Wesseling, K. H.; van Montfrans, G. A.

    1995-01-01

    We determined the continuous 24-hour profile of mean arterial pressure, heart rate, stroke volume, cardiac output, and total peripheral resistance in eight healthy ambulatory volunteers. Beat-to-beat intra-arterial blood pressure was recorded with the Oxford system; subjects were ambulant during

  8. Clinical monitoring of systemic hemodynamics in critically ill newborns.

    NARCIS (Netherlands)

    Boode, W.P. de

    2010-01-01

    Circulatory failure is a major cause of mortality and morbidity in critically ill newborn infants. Since objective measurement of systemic blood flow remains very challenging, neonatal hemodynamics is usually assessed by the interpretation of various clinical and biochemical parameters. An overview

  9. Relationship between neurometabolite derangement and neurocognitive dysfunction in systemic lupus erythematosus.

    Science.gov (United States)

    Brooks, W M; Jung, R E; Ford, C C; Greinel, E J; Sibbitt, W L

    1999-01-01

    To determine the relationship between neurochemical markers of brain injury and brain dysfunction associated with systemic lupus erythematosus (SLE). Patients with SLE (n = 12) were studied using magnetic resonance spectroscopic imaging at 1.5 Tesla to determine neurochemistry and a neurocognitive testing battery to determine brain dysfunction. N-acetylaspartate (NAA), creatine (Cre), and choline (Cho) concentrations were measured in white (WM) and gray (GM) matter and expressed as the ratios NAA/Cho, NAA/Cre, and Cho/Cre. Neurocognitive testing results were expressed as a composite z score. Disease activity was quantified by SLE Disease Activity Index (SLEDAI) and disease injury by Systemic Lupus International Collaborating Clinics (SLICC)/American College of Rheumatology Damage Index. Neurochemical measures of brain injury were correlated with neurocognitive testing z scores: NAA/Cho in WM (r = 0.77, p = 0.003) and GM (r = 0.67, p = 0.017); WM Cho/Cre also correlated with total z score (r = -0.74, p = 0.006). Neurometabolite ratios and SLICC were correlated: GM NAA/Cho (r = -0.70, p = 0.011 ) and NAA/Cre (r = -0.71, p = 0.01) and WM Cho/Cre (r = 0.66, p = 0.02). Correlations between neurometabolite ratios and SLEDAI did not reach significance. Brain function is closely correlated with brain injury assessed noninvasively by proton magnetic resonance spectroscopy. This important finding further supports the use of magnetic resonance spectroscopy to evaluate brain injury in SLE.

  10. Effects of Dietary Nitrates on Systemic and Cerebrovascular Hemodynamics

    Science.gov (United States)

    Curry, Bryan H.; Adams, Richard G.; Asadi, M. Sadegh; Millis, Richard M.; Haddad, Georges E.

    2013-01-01

    Cerebral blood flow dysregulation is often associated with hypertension. We hypothesized that a beetroot juice (BRJ) treatment could decrease blood pressure and cerebrovascular resistance (CVR). We subjected 12 healthy females to control and BRJ treatments. Cerebrovascular resistance index (CVRI), systolic blood pressure (SBP), total vascular resistance (TVR), and the heart rate-systolic pressure product (RPP) measured at rest and at two exercise workloads were lower after the BRJ treatment. CVRI, SBP, and RPP were lower without a lower TVR at the highest exercise level. These findings suggest improved systemic and cerebral hemodynamics that could translate into a dietary treatment for hypertension. PMID:24455404

  11. Deranged Bioenergetics and Defective Redox Capacity in T Lymphocytes and Neutrophils Are Related to Cellular Dysfunction and Increased Oxidative Stress in Patients with Active Systemic Lupus Erythematosus

    Directory of Open Access Journals (Sweden)

    Ko-Jen Li

    2012-01-01

    Full Text Available Urinary excretion of N-benzoyl-glycyl-Nε-(hexanonyllysine, a biomarker of oxidative stress, was higher in 26 patients with active systemic lupus erythematosus (SLE than in 11 non-SLE patients with connective tissue diseases and in 14 healthy volunteers. We hypothesized that increased oxidative stress in active SLE might be attributable to deranged bioenergetics, defective reduction-oxidation (redox capacity, or other factors. We demonstrated that, compared to normal cells, T lymphocytes (T and polymorphonuclear neutrophils (PMN of active SLE showed defective expression of facilitative glucose transporters GLUT-3 and GLUT-6, which led to increased intracellular basal lactate and decreased ATP production. In addition, the redox capacity, including intracellular GSH levels and the enzyme activity of glutathione peroxidase (GSH-Px and γ-glutamyl-transpeptidase (GGT, was decreased in SLE-T. Compared to normal cells, SLE-PMN showed decreased intracellular GSH levels, and GGT enzyme activity was found in SLE-PMN and enhanced expression of CD53, a coprecipitating molecule for GGT. We conclude that deranged cellular bioenergetics and defective redox capacity in T and PMN are responsible for cellular immune dysfunction and are related to increased oxidative stress in active SLE patients.

  12. Short Report Biochemical derangements prior to emergency ...

    African Journals Online (AJOL)

    diagnoses frequently associated with biochemical derangement. A substantial proportion displayed clinically significant derangements in their blood tests. These derangements can result in anorexia, nausea, muscle weakness, paralytic ileus, and ...

  13. [System analytical approach of lung function and hemodynamics].

    Science.gov (United States)

    Naszlady, Attila; Kiss, Lajos

    2009-02-15

    The authors critically analyse the traditional views in physiology and complete them with new statements based on computer model simulations of lung function and of hemodynamics. Conclusions are derived for the clinical practice as follows: the four-dimensional function curves are similar in both systems; there is a "waterfall" zone in the pulmonary blood perfusion; the various time constants of pulmonary regions can modify the blood gas values; pulmonary capillary pressure is equal to pulmonary arterial diastole pressure; heart is not a pressure pump, but a flow source; ventricles are loaded by the input impedance of the arterial systems and not by the total vascular (ohmlike) resistance; optimum heart rate in rest depends on the length of the aorta; this law of heart rate, based on the principle of resonance is valid along the mammalian allometric line; tachycardia decreases the input impedance; using positive end expiratory pressure respirators the blood gas of pulmonary artery should be followed; coronary circulation should be assessed in beat per milliliter, the milliliter per minute may be false. These statements are compared to related references.

  14. Relationship between systemic hemodynamics and ambulatory blood pressure level are sex dependent.

    Science.gov (United States)

    Alfie, J; Waisman, G D; Galarza, C R; Magi, M I; Vasvari, F; Mayorga, L M; Cámera, M I

    1995-12-01

    Sex-related differences in systemic hemodynamics were analyzed by means of cardiac index and systemic vascular resistance according to the level of daytime ambulatory blood pressure. In addition, we assessed the relations between ambulatory blood pressure measurements and systemic hemodynamics in male and female patients. We prospectively included 52 women and 53 men referred to our unit for evaluation of arterial hypertension. Women and men were grouped according to the level of daytime mean arterial pressure: or = 110 mm Hg. Patients underwent noninvasive evaluation of resting hemodynamics (impedance cardiography) and 24-hour ambulatory blood pressure monitoring. Compared with women men with lower daytime blood pressure had a 12% higher systemic vascular resistance index (P = NS) and a 14% lower cardiac index (P < .02), whereas men with higher daytime blood pressure had a 25% higher vascular resistance (P < .003) and a 21% lower cardiac index (P < .0004). Furthermore, in men systemic vascular resistance correlated positively with both daytime and nighttime systolic and diastolic blood pressures, whereas cardiac index correlated negatively only with daytime diastolic blood pressure. In contrast, women did not exhibit any significant correlation between hemodynamic parameters and ambulatory blood pressure measurements. In conclusion, sex-related differences in systemic hemodynamics were more pronounced in the group with higher daytime hypertension. The relations between systemic hemodynamics and ambulatory blood pressure level depended on the sex of the patient. In men a progressive circulatory impairment underlies the increasing level of ambulatory blood pressure, but this was not observed in women.

  15. PGC-1alpha deficiency causes multi-system energy metabolic derangements: muscle dysfunction, abnormal weight control and hepatic steatosis.

    Directory of Open Access Journals (Sweden)

    Teresa C Leone

    2005-04-01

    Full Text Available The gene encoding the transcriptional coactivator peroxisome proliferator-activated receptor-gamma coactivator-1alpha (PGC-1alpha was targeted in mice. PGC-1alpha null (PGC-1alpha(-/- mice were viable. However, extensive phenotyping revealed multi-system abnormalities indicative of an abnormal energy metabolic phenotype. The postnatal growth of heart and slow-twitch skeletal muscle, organs with high mitochondrial energy demands, is blunted in PGC-1alpha(-/- mice. With age, the PGC-1alpha(-/- mice develop abnormally increased body fat, a phenotype that is more severe in females. Mitochondrial number and respiratory capacity is diminished in slow-twitch skeletal muscle of PGC-1alpha(-/- mice, leading to reduced muscle performance and exercise capacity. PGC-1alpha(-/- mice exhibit a modest diminution in cardiac function related largely to abnormal control of heart rate. The PGC-1alpha(-/- mice were unable to maintain core body temperature following exposure to cold, consistent with an altered thermogenic response. Following short-term starvation, PGC-1alpha(-/- mice develop hepatic steatosis due to a combination of reduced mitochondrial respiratory capacity and an increased expression of lipogenic genes. Surprisingly, PGC-1alpha(-/- mice were less susceptible to diet-induced insulin resistance than wild-type controls. Lastly, vacuolar lesions were detected in the central nervous system of PGC-1alpha(-/- mice. These results demonstrate that PGC-1alpha is necessary for appropriate adaptation to the metabolic and physiologic stressors of postnatal life.

  16. Circadian rhythms in systemic hemodynamics and renal function in healthy subjects and patients with nephrotic syndrome

    NARCIS (Netherlands)

    Voogel, A. J.; Koopman, M. G.; Hart, A. A.; van Montfrans, G. A.; Arisz, L.

    2001-01-01

    The resemblance of the circadian rhythm of glomerular filtration rate (GFR) to that of arterial blood pressure (BP) suggests that systemic hemodynamic factors contribute to this variation. In the present study, this was investigated using continuous BP monitoring and pulse wave analysis. The study

  17. Effect of volume expansion on systemic hemodynamics and central and arterial blood volume in cirrhosis

    DEFF Research Database (Denmark)

    Møller, S; Bendtsen, F; Henriksen, Jens Henrik Sahl

    1995-01-01

    BACKGROUND & AIMS: Systemic vasodilatation in cirrhosis may lead to hemodynamic alterations with reduced effective blood volume and decreased arterial blood pressure. This study investigates the response of acute volume expansion on hemodynamics and regional blood volumes in patients with cirrhosis...... and in controls. METHODS: Thirty-nine patients with cirrhosis (12 patients with Child-Turcotte class A, 14 with class B, and 13 with class C) and 6 controls were studied. During hepatic vein catheterization, cardiac output, systemic vascular resistance, central and arterial blood volume, noncentral blood volume...... in patients with either class B or class C. Conversely, the noncentral blood volume increased in patients with class B and C. In both patients and controls, the cardiac output increased and the systemic vascular resistance decreased, whereas the mean arterial blood pressure did not change significantly...

  18. Hemodynamic analysis of sequential graft from right coronary system to left coronary system.

    Science.gov (United States)

    Wang, Wenxin; Mao, Boyan; Wang, Haoran; Geng, Xueying; Zhao, Xi; Zhang, Huixia; Xie, Jinsheng; Zhao, Zhou; Lian, Bo; Liu, Youjun

    2016-12-28

    Sequential and single grafting are two surgical procedures of coronary artery bypass grafting. However, it remains unclear if the sequential graft can be used between the right and left coronary artery system. The purpose of this paper is to clarify the possibility of right coronary artery system anastomosis to left coronary system. A patient-specific 3D model was first reconstructed based on coronary computed tomography angiography (CCTA) images. Two different grafts, the normal multi-graft (Model 1) and the novel multi-graft (Model 2), were then implemented on this patient-specific model using virtual surgery techniques. In Model 1, the single graft was anastomosed to right coronary artery (RCA) and the sequential graft was adopted to anastomose left anterior descending (LAD) and left circumflex artery (LCX). While in Model 2, the single graft was anastomosed to LAD and the sequential graft was adopted to anastomose RCA and LCX. A zero-dimensional/three-dimensional (0D/3D) coupling method was used to realize the multi-scale simulation of both the pre-operative and two post-operative models. Flow rates in the coronary artery and grafts were obtained. The hemodynamic parameters were also showed, including wall shear stress (WSS) and oscillatory shear index (OSI). The area of low WSS and OSI in Model 1 was much less than that in Model 2. Model 1 shows optimistic hemodynamic modifications which may enhance the long-term patency of grafts. The anterior segments of sequential graft have better long-term patency than the posterior segments. With rational spatial position of the heart vessels, the last anastomosis of sequential graft should be connected to the main branch.

  19. An Integrative Model of the Cardiovascular System Coupling Heart Cellular Mechanics with Arterial Network Hemodynamics

    Science.gov (United States)

    Kim, Young-Tae; Lee, Jeong Sang; Youn, Chan-Hyun; Choi, Jae-Sung

    2013-01-01

    The current study proposes a model of the cardiovascular system that couples heart cell mechanics with arterial hemodynamics to examine the physiological role of arterial blood pressure (BP) in left ventricular hypertrophy (LVH). We developed a comprehensive multiphysics and multiscale cardiovascular model of the cardiovascular system that simulates physiological events, from membrane excitation and the contraction of a cardiac cell to heart mechanics and arterial blood hemodynamics. Using this model, we delineated the relationship between arterial BP or pulse wave velocity and LVH. Computed results were compared with existing clinical and experimental observations. To investigate the relationship between arterial hemodynamics and LVH, we performed a parametric study based on arterial wall stiffness, which was obtained in the model. Peak cellular stress of the left ventricle and systolic blood pressure (SBP) in the brachial and central arteries also increased; however, further increases were limited for higher arterial stiffness values. Interestingly, when we doubled the value of arterial stiffness from the baseline value, the percentage increase of SBP in the central artery was about 6.7% whereas that of the brachial artery was about 3.4%. It is suggested that SBP in the central artery is more critical for predicting LVH as compared with other blood pressure measurements. PMID:23960442

  20. Hemodynamics and Blood Coagulation System in Patients Operated Following Ulcer Disease Hemorrhagia

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    V. V. Filatov

    2013-01-01

    Full Text Available Objective: to evaluate the clinical efficacy of hypoxen and nutrients used in the combination therapy of patients operated for bleeding gastroduodenal ulcer. Subjects and methods. Seventy-four patients were examined and treated. All the patients were divided into 3 groups: 1 standard therapy + hypoxen in a daily dose of 1 g for a week; 2 standard therapy + hypox-en and nutrients; 3 standard therapy only. Hypoxen and nutrients were administered on postoperative day 1 via an enter-al feeding tube. Systemic hemodynamic and hemostatic parameters were determined using MICAR-RHEO hardware-software rheographic unit APG2-01 analyzer, respectively. Results. It was established that the hyper- and eukinetic hemodynamic types were predominant before surgery and the eukinetic type was prevalent in the early postoperative period. Hypoxen and nutrients were observed to positively affect central hemodynamic parameters, such as blood pressure, cardiac output, circulating blood volume, and heart rate. Hypercoagulation changes (shorter blood clotting time in a study group and elevated serum fibrinogen levels in a comparison group on postoperative day 10 suggest that the hemostatic parameters should be monitored and corrected as soon as possible. Key words: ulcer disease, hypoxen, nutritional support, blood circulation, hemostatic system.

  1. Heart and aortic baroreceptors: operation in providing hemodynamic processes in cardiovascular system

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    Mikhail Y. Rudenko

    2013-11-01

    Full Text Available Aims Up to the present, ECGs have been classified on the basis of the analysis of the ECG curve shape. But this made impossible to classify many ECG shapes. The most promising methods for the classification must evaluate each of the 10 cardiac cycle phases both by their functions and hemodynamic parameters. The aim hereof is to develop the new classification principles for all possible ECG shape variations. Materials and methods The heart cycle phase analysis method is used to calculate the hemodynamic parameters in each of 10 phases, like the phase-related blood volumes and the level of contraction of the corresponding cardiovascular musculature determining its function dynamics in the cardiac cycle phase structure related to the compensation mechanism for maintaining normal hemodynamics. Results An ECG phase changes periodic table consisting of 10 groups of the actual ECG curves typical for the corresponding pathologies is proposed. Each group contains 4 levels of characteristic phase changes. Conclusion The ECG phase changes periodic table is the first attempt to classify the great variety of the ECG shapes. In this case the proposed system requires further investigations. It has been demonstrated that the theoretical concept of the table is in compliance with practice. Further it is planned to improve characteristics of every group and every level.

  2. Plasma ADAMTS-13 protein is not associated with portal hypertension or hemodynamic changes in patients with cirrhosis

    DEFF Research Database (Denmark)

    Wiese, Signe; Timm, Annette; Nielsen, Lars B

    2016-01-01

    catheterization with measurement of splanchnic and systemic hemodynamics, and plasma ADAMTS13 protein concentration in a hepatic vein and the femoral artery. RESULTS: ADAMTS13 protein concentrations were increased in cirrhotic patients compared with controls (774ng/ml [IQR: 585-955] vs. 538ng/ml [IQR: 484-631], p...... in cirrhosis. However, ADAMTS13 was unrelated to portal hypertension and systemic hemodynamics. In conclusion, ADAMTS13 does not appear to be associated to disease severity or the hemodynamic derangement in patients with cirrhosis.......BACKGROUND: Activated hepatic stellate cells synthesize the matrix metalloprotease ADAMTS13, which may be involved in the development of liver cirrhosis and portal hypertension. Plasma ADAMTS13 activity has been reported as both increased and decreased in cirrhosis, but ADAMTS13 protein has...

  3. Joint state and parameter estimation for a class of cascade systems: Application to a hemodynamic model

    KAUST Repository

    Zayane, Chadia

    2014-06-01

    In this paper, we address a special case of state and parameter estimation, where the system can be put on a cascade form allowing to estimate the state components and the set of unknown parameters separately. Inspired by the nonlinear Balloon hemodynamic model for functional Magnetic Resonance Imaging problem, we propose a hierarchical approach. The system is divided into two subsystems in cascade. The state and input are first estimated from a noisy measured signal using an adaptive observer. The obtained input is then used to estimate the parameters of a linear system using the modulating functions method. Some numerical results are presented to illustrate the efficiency of the proposed method.

  4. Hemodynamic Profiling in Complicated Pregnancies

    NARCIS (Netherlands)

    J.M.J. Cornette (Jérôme)

    2016-01-01

    textabstractIn order to permit a successful pregnancy outcome, the cardiovascular system must undergo substantial changes. This thesis addresses the hemodynamics in several pregnancy complications. A general overview of normal hemodynamic adaptation to pregnancy is provided . Several techniques of

  5. Intrarenal hemodynamics and impaired tubular functions in patients with systemic lupus erythematosus

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    A N Maksudova

    2010-01-01

    Conclusion. The smaller and no RFR in patients without signs of nephropathy may suggest occult intrarenal hemodynamic disorders detected during the dopamine stress test. Tubular impairments in SLE were largely characteristic of patients with intrarenal hemodynamic disorders.

  6. Hemostatic derangement in dengue hemorrhagic fever.

    Science.gov (United States)

    Chuansumrit, Ampaiwan; Chaiyaratana, Wathanee

    2014-01-01

    Dengue hemorrhagic fever (DHF) is a more severe manifestation of dengue virus infection. Patients with DHF exhibit abnormal hematological indices, including high hematocrit, low white blood cells, low neutrophils, high lymphocytes, increased atypical lymphocytes, low platelets, slightly prolonged activated partial thromboplastin time, prothrombin time, and thrombin time. Abnormal platelet functions manifest as impaired platelet aggregation to ADP, and concurrent increases in plasma thromboglobulin and platelet factor 4 levels are also seen. Variable reductions in the activities of coagulation factors including prothrombin, V, VII, VIII, IX, and X may be present. The plasma level of antithrombin is typically normal, but protein C and protein S are modestly reduced. Within the fibrinolytic system, slightly increased levels of tissue-plasminogen activator accompanied by slightly increased plasminogen activator inhibitor-1 and decreased thrombin activatable fibrinolysis inhibitor have been demonstrated. These derangements are prominent in patients with DHF grades III and IV, collectively known as dengue shock syndrome. Moreover, patients with excessive depletion of intravascular volume from plasma leakage and/or massive bleeding from endothelial dysfunction, thrombocytopenia, platelet dysfunction, and coagulopathy may exhibit shock, prolonged shock and repeated shock. DIC is also commonly found in these complicated patients. However, most patients recover spontaneously with normalization of abnormal laboratory profiles during the convalescent stage or within one to two weeks after defervescence. © 2013.

  7. Systemic Hemodynamic Atherothrombotic Syndrome and Resonance Hypothesis of Blood Pressure Variability: Triggering Cardiovascular Events.

    Science.gov (United States)

    Kario, Kazuomi

    2016-07-01

    Blood pressure (BP) exhibits different variabilities and surges with different time phases, from the shortest beat-by-beat to longest yearly changes. We hypothesized that the synergistic resonance of these BP variabilites generates an extraordinarily large dynamic surge in BP and triggers cardiovascular events (the resonance hypothesis). The power of pulses is transmitted to the peripheral sites without attenuation by the large arteries, in individuals with stiffened arteries. Thus, the effect of a BP surge on cardiovascular risk would be especially exaggerated in high-risk patients with vascular disease. Based on this concept, our group recently proposed a new theory of systemic hemodynamic atherothromboltic syndrome (SHATS), a vicious cycle of hemodynamic stress and vascular disease that advances organ damage and triggers cardiovascular disease. Clinical phenotypes of SHATS are large-artery atherothombotic diseases such as stroke, coronary artery disease, and aortic and pheripheral artery disease; small-artery diseases, and microcirculation-related disease such as vascular cognitive dysfunction, heart failure, and chronic kidney disease. The careful consideration of BP variability and vascular diseases such as SHATS, and the early detection and management of SHATS, will achieve more effective individualized cardiovascular protection. In the near future, information and communication technology-based 'anticipation medicine' predicted by the changes of individual BP values could be a promising approach to achieving zero cardiovascular events.

  8. Hemodynamic, morphometric and autonomic patterns in hypertensive rats - renin-angiotensin system modulation

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    Fernanda S. Zamo

    2010-01-01

    Full Text Available BACKGROUND: Spontaneously hypertensive rats develop left ventricular hypertrophy, increased blood pressure and blood pressure variability, which are important determinants of heart damage, like the activation of renin-angiotensin system. AIMS: To investigate the effects of the time-course of hypertension over 1 hemodynamic and autonomic patterns (blood pressure; blood pressure variability; heart rate; 2 left ventricular hypertrophy; and 3 local and systemic Renin-angiotensin system of the spontaneously hypertensive rats. METHODS: Male spontaneously hypertensive rats were randomized into two groups: young (n=13 and adult (n=12. Hemodynamic signals (blood pressure, heart rate, blood pressure variability (BPV and spectral analysis of the autonomic components of blood pressure were analyzed. LEFT ventricular hypertrophy was measured by the ratio of LV mass to body weight (mg/g, by myocyte diameter (μm and by relative fibrosis area (RFA, %. ACE and ACE2 activities were measured by fluorometry (UF/min, and plasma renin activity (PRA was assessed by a radioimmunoassay (ng/mL/h. Cardiac gene expressions of Agt, Ace and Ace2 were quantified by RT-PCR (AU. RESULTS: The time-course of hypertension in spontaneously hypertensive rats increased BPV and reduced the alpha index in adult spontaneously hypertensive rats. Adult rats showed increases in left ventricular hypertrophy and in RFA. Compared to young spontaneously hypertensive rats, adult spontaneously hypertensive rats had lower cardiac ACE and ACE2 activities, and high levels of PRA. No change was observed in gene expression of Renin-angiotensin system components. CONCLUSIONS: The observed autonomic dysfunction and modulation of Renin-angiotensin system activity are contributing factors to end-organ damage in hypertension and could be interacting. Our findings suggest that the management of hypertensive disease must start before blood pressure reaches the highest stable levels and the consequent

  9. Longitudinal Hemodynamic Measurements in Swine Heart Failure Using a Fully Implantable Telemetry System

    Science.gov (United States)

    Choy, Jenny S.; Zhang, Zhen-Du; Pitsillides, Koullis; Sosa, Margo; Kassab, Ghassan S.

    2014-01-01

    Chronic monitoring of heart rate, blood pressure, and flow in conscious free-roaming large animals can offer considerable opportunity to understand the progression of cardiovascular diseases and can test new diagnostics and therapeutics. The objective of this study was to demonstrate the feasibility of chronic, simultaneous measurement of several hemodynamic parameters (left ventricular pressure, systemic pressure, blood flow velocity, and heart rate) using a totally implantable multichannel telemetry system in swine heart failure models. Two solid-state blood pressure sensors were inserted in the left ventricle and the descending aorta for pressure measurements. Two Doppler probes were placed around the left anterior descending (LAD) and the brachiocephalic arteries for blood flow velocity measurements. Electrocardiographic (ECG) electrodes were attached to the surface of the left ventricle to monitor heart rate. The telemeter body was implanted in the right side of the abdomen under the skin for approximately 4 to 6 weeks. The animals were subjected to various heart failure models, including volume overload (A-V fistula, n = 3), pressure overload (aortic banding, n = 2) and dilated cardiomyopathy (pacing-induced tachycardia, n = 3). Longitudinal changes in hemodynamics were monitored during the progression of the disease. In the pacing-induced tachycardia animals, the systemic blood pressure progressively decreased within the first 2 weeks and returned to baseline levels thereafter. In the aortic banding animals, the pressure progressively increased during the development of the disease. The pressure in the A-V fistula animals only showed a small increase during the first week and remained stable thereafter. The results demonstrated the ability of this telemetry system of long-term, simultaneous monitoring of blood flow, pressure and heart rate in heart failure models, which may offer significant utility for understanding cardiovascular disease

  10. Systemic and regional hemodynamic effects of enalaprilat infusion in experimental normotensive sepsis

    Directory of Open Access Journals (Sweden)

    L. Rahal

    Full Text Available Angiotensin-converting enzyme inhibitors have been shown to improve splanchnic perfusion in distinct shock states. We hypothesized that enalaprilat potentiates the benefits of early fluid resuscitation in severe experimental sepsis, particularly in the splanchnic region. Anesthetized and mechanically ventilated mongrel dogs received an intravenous infusion of live Escherichia coli over a period of 30 min. Thereafter, two interventions were performed: fluid infusion (normal saline, 32 mL/kg over 30 min and enalaprilat infusion (0.02 mg kg-1 min-1 for 60 min in randomized groups. The following groups were studied: controls (fluid infusion, N = 4, E1 (enalaprilat infusion followed by fluid infusion, N = 5 and E2 (fluid infusion followed by enalaprilat infusion, N = 5. All animals were observed for a 120 min after bacterial infusion. Mean arterial pressure, cardiac output (CO, portal vein blood flow (PVBF, systemic and regional oxygen-derived variables, and lactate levels were measured. Rapid and progressive reductions in CO and PVBF were induced by the infusion of live bacteria, while minor changes were observed in mean arterial pressure. Systemic and regional territories showed a significant increase in oxygen extraction and lactate levels. Widening venous-arterial and portal-arterial pCO2 gradients were also detected. Fluid replacement promoted transient benefits in CO and PVBF. Enalaprilat after fluid resuscitation did not affect systemic or regional hemodynamic variables. We conclude that in this model of normotensive sepsis inhibition of angiotensin-converting enzyme did not interfere with the course of systemic or regional hemodynamic and oxygen-derived variables.

  11. A note on some identities of derangement polynomials.

    Science.gov (United States)

    Kim, Taekyun; Kim, Dae San; Jang, Gwan-Woo; Kwon, Jongkyum

    2018-01-01

    The problem of counting derangements was initiated by Pierre Rémond de Montmort in 1708 (see Carlitz in Fibonacci Q. 16(3):255-258, 1978, Clarke and Sved in Math. Mag. 66(5):299-303, 1993, Kim, Kim and Kwon in Adv. Stud. Contemp. Math. (Kyungshang) 28(1):1-11 2018. A derangement is a permutation that has no fixed points, and the derangement number [Formula: see text] is the number of fixed-point-free permutations on an n element set. In this paper, we study the derangement polynomials and investigate some interesting properties which are related to derangement numbers. Also, we study two generalizations of derangement polynomials, namely higher-order and r -derangement polynomials, and show some relations between them. In addition, we express several special polynomials in terms of the higher-order derangement polynomials by using umbral calculus.

  12. [Effects of different levels of end-expiratory pressure on hemodynamic, respiratory mechanics and systemic stress response during laparoscopic cholecystectomy].

    Science.gov (United States)

    Sen, Oznur; Erdogan Doventas, Yasemin

    General anesthesia causes reduction of functional residual capacity. And this decrease can lead to atelectasis and intrapulmonary shunting in the lung. In this study we want to evaluate the effects of 5 and 10cmH 2 O PEEP levels on gas exchange, hemodynamic, respiratory mechanics and systemic stress response in laparoscopic cholecystectomy. American Society of Anesthesiologist I-II physical status 43 patients scheduled for laparoscopic cholecystectomy were randomly selected to receive external PEEP of 5cmH 2 O (PEEP 5 group) or 10cmH 2 O PEEP (PEEP 10 group) during pneumoperitoneum. Basal hemodynamic parameters were recorded, and arterial blood gases (ABG) and blood sampling were done for cortisol, insulin and glucose level estimations to assess the systemic stress response before induction of anesthesia. Thirty minutes after the pneumoperitoneum, the respiratory and hemodynamic parameters were recorded again and ABG and sampling for cortisol, insulin, and glucose levels were repeated. Lastly hemodynamic parameters were recorded; ABG analysis and sampling for stress response levels were taken after 60minutes from extubation. There were no statistical differences between the two groups about hemodynamic and respiratory parameters except mean airway pressure (P mean ). P mean , compliance and PaO 2 ; pH values were higher in 'PEEP 10 group'. Also, PaCO 2 values were lower in 'PEEP 10 group'. No differences were observed between insulin and lactic acid levels in the two groups. But postoperative cortisol level was significantly lower in 'PEEP 10 group'. Ventilation with 10cmH 2 O PEEP increases compliance and oxygenation, does not cause hemodynamic and respiratory complications and reduces the postoperative stress response. Copyright © 2016 Sociedade Brasileira de Anestesiologia. Publicado por Elsevier Editora Ltda. All rights reserved.

  13. Effects of different levels of end-expiratory pressure on hemodynamic, respiratory mechanics and systemic stress response during laparoscopic cholecystectomy.

    Science.gov (United States)

    Sen, Oznur; Erdogan Doventas, Yasemin

    General anesthesia causes reduction of functional residual capacity. And this decrease can lead to atelectasis and intrapulmonary shunting in the lung. In this study we want to evaluate the effects of 5 and 10cmH 2 O PEEP levels on gas exchange, hemodynamic, respiratory mechanics and systemic stress response in laparoscopic cholecystectomy. American Society of Anesthesiologist I-II physical status 43 patients scheduled for laparoscopic cholecystectomy were randomly selected to receive external PEEP of 5cmH 2 O (PEEP 5 group) or 10cmH 2 O PEEP (PEEP 10 group) during pneumoperitoneum. Basal hemodynamic parameters were recorded, and arterial blood gases (ABG) and blood sampling were done for cortisol, insulin and glucose level estimations to assess the systemic stress response before induction of anesthesia. Thirty minutes after the pneumoperitoneum, the respiratory and hemodynamic parameters were recorded again and ABG and sampling for cortisol, insulin, and glucose levels were repeated. Lastly hemodynamic parameters were recorded; ABG analysis and sampling for stress response levels were taken after 60minutes from extubation. There were no statistical differences between the two groups about hemodynamic and respiratory parameters except mean airway pressure (P mean ). P mean , compliance and PaO 2 ; pH values were higher in 'PEEP 10 group'. Also, PaCO 2 values were lower in 'PEEP 10 group'. No differences were observed between insulin and lactic acid levels in the two groups. But postoperative cortisol level was significantly lower in 'PEEP 10 group'. Ventilation with 10cmH 2 O PEEP increases compliance and oxygenation, does not cause hemodynamic and respiratory complications and reduces the postoperative stress response. Copyright © 2016 Sociedade Brasileira de Anestesiologia. Published by Elsevier Editora Ltda. All rights reserved.

  14. Hemodynamic behavior modeling of a Virtual Surgical Patient based on a Fuzzy Expert System.

    Directory of Open Access Journals (Sweden)

    Paulo Farias Paiva

    2016-07-01

    Full Text Available The Virtual Reality (VR allows its users to experience a sense of being immersed in synthetic 3D scenarios generated by computer graphics. The so-called Virtual Environments (VEs based on RV can be applied to medical education, enabling: repetitive training and the development of psychomotor skills in surgical procedures without compromising real patients. Surgical simulators that feature Dynamic Virtual Patients (VPs, that is, reacts physiologically to interventions and medical decisions made during the training. These systems present more realism while it offers the possibility of varying clinical cases. This work has as main objective to discuss important issues of modeling the hemodynamic performance of a VP, specifically to simulate blood pressure values (both sistolic and diastolic variables. The model of a VP is presented as result as well as is presented an architecture for its integration to simulators based on VR.

  15. Effect of Prometheus liver assist system on systemic hemodynamics in patients with cirrhosis: a randomized controlled study.

    Science.gov (United States)

    Dethloff, Thomas; Tofteng, Flemming; Frederiksen, Hans-Jorgen; Hojskov, Michael; Hansen, Bent-Adel; Larsen, Fin-Stolze

    2008-04-07

    To evaluate treatment safety and hemodynamic changes during a single 6-h treatment with the Prometheus liver assist system in a randomized, controlled study. Twenty-four patients were randomized to either the study group or to one of two control groups: Fractionated Plasma Separation Adsorption and Dialysis, Prometheus system (Study group; n = 8); Molecular Adsorbent Recirculation System (MARS) (Control group 1, n = 8); or hemodialysis (Control group 2; n = 8). All patients included in the study had decompensated cirrhosis at the time of the inclusion into the study. Circulatory changes were monitored with a Swan-Ganz catheter and bilirubin and creatinine were monitored as measures of protein-bound and water-soluble toxins. Systemic hemodynamics did not differ between treatment and control groups apart from an increase in arterial pressure in the MARS group (P = 0.008). No adverse effects were observed in any of the groups. Creatinine levels significantly decreased in the MARS group (P = 0.03) and hemodialysis group (P = 0.04). Platelet count deceased in the Prometheus group (P = 0.04). Extra-corporal liver support with Prometheus is proven to be safe in patients with endstage liver disease but does not exert the beneficial effects on arterial pressure as seen in the MARS group.

  16. Temporomandibular Joint Anatomy and Derangements

    Directory of Open Access Journals (Sweden)

    Bahadır Odabaş

    2008-01-01

    Full Text Available Temporomandibular joint (TMJ is a diartrodial joint which is located just before the outer ear way and between the mandibular fossa and mandibular condyle. TMJ has rotation and translation movements. Approximately the 30-50 percent of the population has joint click. Most of the patients which have TMJ click may suffer from disc displacement. By the presence of disharmony between TMJ and occlusion and masticatory muscles, natural balance disappears. Therefore the function of the craniomandibular system and the factors that affects dysfunction must be considered when treatment planning is built.

  17. Effect of Prometheus liver assist system on systemic hemodynamics in patients with cirrhosis: a randomized controlled study

    DEFF Research Database (Denmark)

    Dethloff, T.; Tofteng, F.; Frederiksen, H.J.

    2008-01-01

    AIM: To evaluate treatment safety and hemodynamic changes during a single 6-h treatment with the Prometheus liver assist system in a randomized, controlled study. METHODS: Twenty-four patients were randomized to either the study group or to one of two control groups: Fractionated Plasma Separation...... Adsorption and Dialysis, Prometheus system (Study group; n = 8); Molecular Adsorbent Recirculation System (MARS) (Control group 1, n = 8); or hemodialysis (Control group 2; n = 8). All patients included in the study had decompensated cirrhosis at the time of the inclusion into the study. Circulatory changes.......008). No adverse effects were observed in any of the groups. Creatinine levels significantly decreased in the MARS group (P = 0.03) and hemodialysis group (P = 0.04). Platelet count deceased in the Prometheus group (P = 0.04). CONCLUSION: Extra-corporal liver support with Prometheus is proven to be safe...

  18. Improving hemodynamics of cardiovascular system under a novel intraventricular assist device support via modeling and simulations.

    Science.gov (United States)

    Zhu, Shidong; Luo, Lin; Yang, Bibo; Li, Xinghui; Wang, Xiaohao

    2017-12-01

    Ventricular assist devices (LVADs) are increasingly recognized for supporting blood circulation in heart failure patients who are non-transplant eligible. Because of its volume, the traditional pulsatile device is not easy to implant intracorporeally. Continuous flow LVADs (CF-LVADs) reduce arterial pulsatility and only offer continuous flow, which is different from physiological flow, and may cause long-term complications in the cardiovascular system. The aim of this study was to design a new pulsatile assist device that overcomes this disadvantage, and to test this device in the cardiovascular system. Firstly, the input and output characteristics of the new device were tested in a simple cardiovascular mock system. A detailed mathematical model was established by fitting the experimental data. Secondly, the model was tested in four pathological cases, and was simulated and coupled with a fifth-order cardiovascular system and a new device model using Matlab software. Using assistance of the new device, we demonstrated that the left ventricle pressure, aortic pressure, and aortic flow of heart failure patients improved to the levels of a healthy individual. Especially, in state IV level heart failure patients, the systolic blood pressure increased from 81.34 mmHg to 132.1 mmHg, whereas the diastolic blood pressure increased from 54.28 mmHg to 78.7 mmHg. Cardiac output increased from 3.21 L/min to 5.16 L/min. The newly-developed assist device not only provided a physiological flow that was similar to healthy individuals, but also effectively improved the ability of the pathological ventricular volume. Finally, the effects of the new device on other hemodynamic parameters are discussed.

  19. Intraoperative non-record-keeping usage of anesthesia information management system workstations and associated hemodynamic variability and aberrancies.

    Science.gov (United States)

    Wax, David B; Lin, Hung-Mo; Reich, David L

    2012-12-01

    Anesthesia information management system workstations in the anesthesia workspace that allow usage of non-record-keeping applications could lead to distraction from patient care. We evaluated whether non-record-keeping usage of the computer workstation was associated with hemodynamic variability and aberrancies. Auditing data were collected on eight anesthesia information management system workstations and linked to their corresponding electronic anesthesia records to identify which application was active at any given time during the case. For each case, the periods spent using the anesthesia information management system record-keeping module were separated from those spent using non-record-keeping applications. The variability of heart rate and blood pressure were also calculated, as were the incidence of hypotension, hypertension, and tachycardia. Analysis was performed to identify whether non-record-keeping activity was a significant predictor of these hemodynamic outcomes. Data were analyzed for 1,061 cases performed by 171 clinicians. Median (interquartile range) non-record-keeping activity time was 14 (1, 38) min, representing 16 (3, 33)% of a median 80 (39, 143) min of procedure time. Variables associated with greater non-record-keeping activity included attending anesthesiologists working unassisted, longer case duration, lower American Society of Anesthesiologists status, and general anesthesia. Overall, there was no independent association between non-record-keeping workstation use and hemodynamic variability or aberrancies during anesthesia either between cases or within cases. Anesthesia providers spent sizable portions of case time performing non-record-keeping applications on anesthesia information management system workstations. This use, however, was not independently associated with greater hemodynamic variability or aberrancies in patients during maintenance of general anesthesia for predominantly general surgical and gynecologic procedures.

  20. Changes in ventricular hemodynamics caused by a systemic-pulmonary shunt.

    Science.gov (United States)

    Keagy, B A; Lucas, C L; Henry, G W; Lores, M E; Wilcox, B R

    1985-10-01

    Systemic pulmonary shunts are both surgically created (Blalock-Taussig anastomosis) and obliterated (patent ductus arteriosus), but the effects of such a vascular communication on left ventricular hemodynamics have not been examined quantitatively. To study these effects, innominate arterial allografts were sutured between the descending thoracic aorta and the left main pulmonary artery in nine mongrel dogs. Left ventricular output (LVO) and shunt flow (SF) were monitored with electromagnetic flow probes while simultaneous phasic and mean pressures were recorded from the right atrium, aorta (AOP), and pulmonary artery. Data points (192) were analyzed while SF was varied between 0.02 and 5.5 liters/min using a variable-sized constricting band. Regression analysis showed increases (P less than 0.01) in LVO, stroke work (SW), and stroke volume (SV) in all dogs which were linearly related to SF (r = 0.64-0.99). Increasing SF was also associated with decreases (P less than 0.01, r = 0.61-0.99) in resistance (RES) facing the left ventricle and in diastolic (D) AOP. To compensate for differences in allograft size and to quantify the effects of a patent shunt, the regression equations were used to compare the percentage change in all parameters at SF = 0 and SF = 1.5 liters/min. Increases occurred in SV (46 +/- 21%), SW (32 +/- 14%), and LVO (48 +/- 21%), and decreases were present in DAOP (15 +/- 12%) and RES (32 +/- 13%). These data show that despite the decreases in pressure or the decreases in resistance facing the left ventricle in the presence of a systemic pulmonary shunt, a substantial increase in stroke work occurs.(ABSTRACT TRUNCATED AT 250 WORDS)

  1. Hemodynamic Support in Sepsis

    Directory of Open Access Journals (Sweden)

    Fatih Yildiz

    2014-04-01

    Full Text Available Sepsis is called systemic inflammatory response syndrome due to infection. When added to organs failure and perfusion abnormality is defined in severe sepsis, Hypotension that do not respond to fluid therapy is as defined septic shock. Fluid resuscitation is a most important parts of the treatment in patients with septic shock. Ongoing hypotension that despite of the adequate fluid therapy, vasopressor support initiation is required. Sepsis and septic shock, hemodynamic support is often understood as the hemodynamic support. The different approaches to the development of methods to track and objective comes up. Patients with severe sepsis and septic shock should be follow in the intensive care unit and rapid fluid replacement and effectual hemodynamic support should be provided.

  2. Prediction of Hemodynamic Response to Epinephrine via Model-Based System Identification.

    Science.gov (United States)

    Bighamian, Ramin; Soleymani, Sadaf; Reisner, Andrew T; Seri, Istvan; Hahn, Jin-Oh

    2016-01-01

    In this study, we present a system identification approach to the mathematical modeling of hemodynamic responses to vasopressor-inotrope agents. We developed a hybrid model called the latency-dose-response-cardiovascular (LDC) model that incorporated 1) a low-order lumped latency model to reproduce the delay associated with the transport of vasopressor-inotrope agent and the onset of physiological effect, 2) phenomenological dose-response models to dictate the steady-state inotropic, chronotropic, and vasoactive responses as a function of vasopressor-inotrope dose, and 3) a physiological cardiovascular model to translate the agent's actions into the ultimate response of blood pressure. We assessed the validity of the LDC model to fit vasopressor-inotrope dose-response data using data collected from five piglet subjects during variable epinephrine infusion rates. The results suggested that the LDC model was viable in modeling the subjects' dynamic responses: After tuning the model to each subject, the r (2) values for measured versus model-predicted mean arterial pressure were consistently higher than 0.73. The results also suggested that intersubject variability in the dose-response models, rather than the latency models, had significantly more impact on the model's predictive capability: Fixing the latency model to population-averaged parameter values resulted in r(2) values higher than 0.57 between measured versus model-predicted mean arterial pressure, while fixing the dose-response model to population-averaged parameter values yielded nonphysiological predictions of mean arterial pressure. We conclude that the dose-response relationship must be individualized, whereas a population-averaged latency-model may be acceptable with minimal loss of model fidelity.

  3. Can short isometric contraction influence coronary, systemic and pulmonary hemodynamics in patients with chronic heart failure?

    Czech Academy of Sciences Publication Activity Database

    Fráňa, P.; Souček, M.; Kára, T.; Sitar, J.; Groch, L.; Jurák, Pavel; Řiháček, I.; Toman, J.; Bartosikova, L.; Dzurova, J.

    2002-01-01

    Roč. 20, č. 4 (2002), s. S17 ISSN 0263-6352. [Scientific meeting of the international society of hypertension - european meeting on hypertension. 23.06.2002-27.06.2002, Praha] R&D Projects: GA ČR GA102/00/1262; GA ČR GA102/02/1339 Institutional research plan: CEZ:AV0Z2065902 Keywords : hemodynamics * heart failure * breathing Subject RIV: FA - Cardiovascular Diseases incl. Cardiotharic Surgery

  4. Brief effect of acupuncture on the peripheral arterial system of the upper limb and systemic hemodynamics in humans.

    Science.gov (United States)

    Takayama, Shin; Seki, Takashi; Watanabe, Masashi; Monma, Yasutake; Yang, San Yue; Sugita, Norihiro; Konno, Satoshi; Saijo, Yoshifumi; Yambe, Tomoyuki; Yaegashi, Nobuo; Yoshizawa, Makoto; Nitta, Shin-ichi

    2010-07-01

    Pulse diagnosis of the peripheral artery is an important technique in Traditional Chinese Medicine, where, in acupuncture therapy, the treatment is adjusted according to the observed changes of the pulse. We investigated the change of blood flow in the peripheral artery and the cardiac index during acupuncture treatment. The aim of this study is to explore the effect of acupuncture on radial and brachial artery blood flow volume and the cardiac index in healthy subjects. Eighteen (18) healthy volunteers were enrolled. Acupuncture was performed bilaterally on LR-3 with manual rotation of the needles. The blood pressure and heart rate were measured at rest and 180 seconds after acupuncture. Radial and brachial artery blood flow volume was monitored continuously by an ultrasound with an echo-tracking system. Cardiac index was measured by impedance cardiography. The hemodynamic parameters were measured before, during, and 30, 60, 180 seconds after acupuncture. The peripheral artery blood flow volume decreased significantly during acupuncture (radial; p acupuncture (radial; p acupuncture. The cardiac index did not change significantly after acupuncture, but systemic vascular resistance index significantly decreased (p acupuncture on LR-3 acupoint, but increased at 180 seconds after acupuncture. This reaction is attributed to the change in peripheral vascular resistance.

  5. Comparison of the effects of pindolol and atenolol on hemodynamic function in systemic hypertension.

    Science.gov (United States)

    Toth, P D; Demeter, R J; Woods, J R; Nyhuis, A W; Judy, W V

    1988-09-01

    A randomized double-blind study was performed on a group of mild hypertensive patients (WHO class I) to compare the hemodynamic effects of pindolol and atenolol. Blood pressure (BP) was monitored with a mercury gauge sphygmomanometer, while cardiac function and peripheral arterial flows were measured by the noninvasive technique of bioelectric impedance. After a 2-week washout period, patients with a diastolic BP greater than 95 mm Hg but less than 114 mm Hg were randomized into the pindolol (29 patients) or atenolol (28) treatment groups. Patients were treated with 1 of the 2 drugs in an incremental fashion for 12 weeks. Cardiovascular function was measured after the washout period and at the end of the 12-week treatment period. Baseline hemodynamics were similar in both groups. The 2 drugs were equally effective in lowering both systolic and diastolic BP. Hemodynamically, pindolol lowered BP by decreasing total peripheral resistance (-406 +/- 145 dynes.s.cm-5) while atenolol decreased cardiac index (-0.2 +/- 0.1 liters/min/m2) associated with a decrease in heart rate (-12 +/- 2 beats/min). Regarding peripheral vascular beds, pindolol lowered arm vascular resistance (-198 +/- 72 mm Hg/liter/min) and leg vascular resistance (-73 +/- 25 mm Hg/liter/min), especially when subjects who did not respond to pindolol were excluded from the analysis. Both arm (5.5 +/- 5.4% increase above baseline) and leg (1.2 +/- 4.4% increase above baseline) arterial flow indexes were maintained with pindolol. Conversely, atenolol decreased the arm arterial flow index (-9,8 +/- 5.6% decrease below baseline), but not significantly and with no change in resistance (+54 +/- 62 mm Hg/liter/min).(ABSTRACT TRUNCATED AT 250 WORDS)

  6. Hemodynamic effects of various support modes of continuous flow LVADs on the cardiovascular system: A numerical study

    Science.gov (United States)

    Song, Zhiming; Gu, Kaiyun; Gao, Bin; Wan, Feng; Chang, Yu; Zeng, Yi

    2014-01-01

    Background The aim of this study was to determine the hemodynamic effects of various support modes of continuous flow left ventricular assist devices (CF-LVADs) on the cardiovascular system using a numerical cardiovascular system model. Material/Methods Three support modes were selected for controlling the CF-LVAD: constant flow mode, constant speed mode, and constant pressure head mode of CF-LVAD. The CF-LVAD is established between the left ventricular apex and the ascending aorta, and was incorporated into the numerical model. Various parameters were evaluated, including the blood assist index (BAI), the left ventricular external work (LVEW), the energy of blood flow (EBF), pulsatility index (PI), and surplus hemodynamic energy (SHE). Results The results show that the constant flow mode, when compared to the constant speed mode and the constant pressure head mode, increases LVEW by 31% and 14%, and EBF by 21% and 15%, respectively, indicating that this mode achieved the best ventricular unloading among the 3 support modes. As BAI is increased, PI and SHE are gradually decreased, whereas PI of the constant pressure head reaches the maximum value. Conclusions The study demonstrates that the continuous flow control mode of the CF-LVAD may achieve the highest ventricular unloading. In contrast, the constant rotational speed mode permits the optimal blood perfusion. Finally, the constant pressure head strategy, permitting optimal pulsatility, should optimize the vascular function. PMID:24793178

  7. Metabolic derangements in IUGR neonates detected at birth using ...

    African Journals Online (AJOL)

    Specific amino acids that were significantly elevated in IUGR neonates included Histidine, Methionine, Arginine, Aspartic, Valine, Alanine, Leucine, Isoleucine, Glutamic acid, Tyrosine, Ornithine, Phenylalanine, and lastly citrulline. These derangements were recognized to be similar to those found in different disorders.

  8. Hemodynamic monitoring during CPR.

    Science.gov (United States)

    Ornato, J P

    1993-02-01

    Real-time hemodynamic monitoring provides useful information that can be used to assess and optimize mechanical and pharmacological interventions during CPR. The standard algorithms should always be the initial approach to resuscitation, because they offer a rapid, logical, coordinated series of treatments with proven success. Pressure and flow measurements during conventional, closed-chest CPR in humans indicate that the technique typically produces a hemodynamic state resembling profound cardiogenic shock, with a low systemic arterial pressure, markedly reduced cardiac output, and high intravascular filling pressures. End-tidal carbon dioxide monitoring provides useful, noninvasive information during clinical resuscitation. A low end-tidal carbon dioxide value during resuscitation should alert the rescuers that something is wrong with ventilation, perfusion, and/or carbon dioxide production and should prompt a search for correctable causes. If one or more hemodynamic parameters are being monitored at the time the patient develops cardiac arrest (eg, an intensive care unit patient who has an arterial line and a pulmonary artery catheter in place), it is appropriate for the resuscitation team to pay attention to the data that are generated during the resuscitation, particularly if the initial algorithm approach is not successful. For patients who are not being monitored at the time of their arrest, end-tidal carbon dioxide measurements provide noninvasive, semiquantitative information that can help the team detect and troubleshoot problems during resuscitation. Further research and better, more affordable technologies are needed to provide in- and out-of-hospital resuscitation teams feedback on the hemodynamic effectiveness of their resuscitative efforts.

  9. Early alterations in cerebral hemodynamics, brain metabolism, and blood-brain barrier permeability in experimental intracerebral hemorrhage.

    Science.gov (United States)

    Lee, E J; Hung, Y C; Lee, M Y

    1999-12-01

    The authors sought to ascertain the nature of the hemodynamic and metabolic derangement underlying acute pathophysiological events that occur after intracerebral hemorrhage (ICH). Cerebral perfusion pressure (CPP), flow velocity (FV) of the middle cerebral artery, and the arteriovenous contents of oxygen and lactate were investigated in 24 dogs subjected to sham operations (Group A, four animals) or intracerebral injections of 3 ml (Group B, 11 animals) or 5 ml (Group C, nine animals) autologous arterial blood. Twelve additional dogs received intravenous injections of 2% Evans blue or trypan blue dye to evaluate blood-brain barrier (BBB) changes. Within 1 hour, animals with ICH exhibited a rise in FV associated with significant reductions (pglycolysis. Furthermore, the data suggest that a selective increase in permeability, rather than anatomical disruption, of the BBB is involved in the acute pathophysiological events that occur after ICH, which may provide a possible gateway for systemic arterial lactate entering the SSS.

  10. Morphologic and hemodynamic analysis of dental pulp in dogs after molar intrusion with the skeletal anchorage system.

    Science.gov (United States)

    Konno, Yuichi; Daimaruya, Takayoshi; Iikubo, Masahiro; Kanzaki, Reiko; Takahashi, Ichiro; Sugawara, Junji; Sasano, Takashi

    2007-08-01

    We have successfully treated skeletal open bite by intruding posterior teeth with the skeletal anchorage system. Our aim in this study was to morphologically and hemodynamically evaluate the changes in pulp tissues when molars are radically intruded. The mandibular fourth premolars of 9 adult beagle dogs were divided into 3 groups: a sham operated group (n = 6, 3 dogs), 4-month intrusion group (n = 6, 3 dogs), and a further 4-month retention group (n = 6, 3 dogs). We evaluated the morphological changes of the pulp and dentin-the amount of vacuolar degeneration in the odontoblast layer, the predentin width and nervous continuity in the pulp tissue, and the pulpal blood-flow response evoked by electrical stimulation in the dental pulp. Extreme molar intrusion with the skeletal anchorage system caused slight degenerative changes in the pulp tissue, followed by recovery after the orthodontic force was released. Circulatory system and nervous functions were basically maintained during the intrusion, although a certain level of downregulation was observed. These morphologic and functional regressive changes in the pulp tissue after molar intrusion improved during the retention period. Histologic changes and changes in pulpal blood flow and function are reversible, even during radical intrusion of molars.

  11. Availability of a remote online hemodynamic monitoring system during treatment in a private dental office for medically high-risk patients

    OpenAIRE

    Yamazaki, Shinya

    2008-01-01

    Shinya Yamazaki, Hiroyoshi Kawaai, Shigeo Sasaki, Kazuhiro Shimamura, Hiroshi Segawa, Takahiro SaitoSpecial Care Department in Dentistry, Ohu University Dental Hospital, Koriyama city, Fukushima prefecture, JapanAbstract: The importance of systemic management to prevent accidents is increasing in dentistry because co-morbid illnesses in an aging society and invasive surgical procedures are increasing. In this prefecture, a new medical system called the remote online hemodynamic monitoring sys...

  12. Fibrotic myofibroblasts manifest genome-wide derangements of translational control.

    Directory of Open Access Journals (Sweden)

    Ola Larsson

    2008-09-01

    Full Text Available As a group, fibroproliferative disorders of the lung, liver, kidney, heart, vasculature and integument are common, progressive and refractory to therapy. They can emerge following toxic insults, but are frequently idiopathic. Their enigmatic propensity to resist therapy and progress to organ failure has focused attention on the myofibroblast-the primary effector of the fibroproliferative response. We have recently shown that aberrant beta 1 integrin signaling in fibrotic fibroblasts results in defective PTEN function, unrestrained Akt signaling and subsequent activation of the translation initiation machinery. How this pathological integrin signaling alters the gene expression pathway has not been elucidated.Using a systems approach to study this question in a prototype fibrotic disease, Idiopathic Pulmonary Fibrosis (IPF; here we show organized changes in the gene expression pathway of primary lung myofibroblasts that persist for up to 9 sub-cultivations in vitro. When comparing IPF and control myofibroblasts in a 3-dimensional type I collagen matrix, more genes differed at the level of ribosome recruitment than at the level of transcript abundance, indicating pathological translational control as a major characteristic of IPF myofibroblasts. To determine the effect of matrix state on translational control, myofibroblasts were permitted to contract the matrix. Ribosome recruitment in control myofibroblasts was relatively stable. In contrast, IPF cells manifested large alterations in the ribosome recruitment pattern. Pathological studies suggest an epithelial origin for IPF myofibroblasts through the epithelial to mesenchymal transition (EMT. In accord with this, we found systems-level indications for TGF-beta -driven EMT as one source of IPF myofibroblasts.These findings establish the power of systems level genome-wide analysis to provide mechanistic insights into fibrotic disorders such as IPF. Our data point to derangements of translational

  13. Profile of plasma lipids and degree of derangements among the ...

    African Journals Online (AJOL)

    This descriptive cross-sectional study was conducted to determine the profile and degree of derangements of plasma lipids among 300 (176 females and 124 males) elderly individuals aged ≥60 years in Morogoro, Tanzania. The calorimetric enzymatic methods and the Friedewal's equation were used for determination of ...

  14. Pattern Of Biochemical Derangements Seen In Chronic Renal ...

    African Journals Online (AJOL)

    Objective: To study the pattern of biochemical derangements in advanced renal failure patients. Subjects and Methods: Ninety adult patients [54 males and 36 females] were recruited from the renal clinic of the University of Nigeria Teaching Hospital (UNTH) Enugu over a period of one year. History and physical ...

  15. Pattern of deranged haemostatic biomarkers among HIV patients: a ...

    African Journals Online (AJOL)

    HIV infection is known to affect haematological profile through various mechanisms; direct effect of the virus on haemopoiesis, natural anticoagulants and vasculopathy. In this study, we determine the pattern of derangement of some haemeostatic biomarkers among HIV cohort with Mild disease (WHO clinical stage I or II), ...

  16. Deranged liver among Sudanese patients with dengue virus ...

    African Journals Online (AJOL)

    Background: Deranged liver is a well-recognized feature of dengue infection, often demonstrated by coagulopathy and mild to moderate increase in transaminase levels although jaundice and fulminant hepatic failure are generally uncommon. Objective: This study aimed to evaluate the hepatic effect of dengue fever ...

  17. Hematological derangement patterns in Nigerian dogs infected with ...

    African Journals Online (AJOL)

    Hematological derangement patterns in Nigerian dogs infected with Trypanosoma brucei : A simple prototype for assessing tolerance to trypanosome infections ... The packed cell volume (PCV), red blood cell (RBC) counts, total and differential white blood cell (WBC) counts and rates of both red blood cell and white blood ...

  18. How Do I Integrate Hemodynamic Variables When Managing Septic Shock?

    Directory of Open Access Journals (Sweden)

    Olfa Hamzaoui

    2016-11-01

    Full Text Available Hemodynamic management of sepsis-induced circulatory failure is complex since this pathological state includes multiple cardiovascular derangements that can vary from patient to patient according to the degree of hypovolemia, of vascular tone depression, of myocardial depression and of microvascular dysfunction. The treatment of the sepsis-induced circulatory failure is thus not univocal and should be adapted on an individual basis. As physical examination is insufficient to obtain a comprehensive picture of the hemodynamic status, numerous hemodynamic variables more or less invasively collected, have been proposed to well assess the severity of each component of the circulatory failure and to monitor the response to therapy. In this article, we first describe the hemodynamic variables, which are the most relevant to be used, emphasizing on their physiological meaning, their validation and their limitations in patients with septic shock. We then proposed a general approach for managing patients with septic shock by describing the logical steps that need to be followed in order to select and deliver the most appropriate therapies. This therapeutic approach is essentially based on knowledge of physiology, of pathophysiology of sepsis, and of published data from clinical studies that addressed the issue of hemodynamic management of septic shock.

  19. Occupational exposure in hemodynamic

    International Nuclear Information System (INIS)

    Silva, Amanda J.; Fernandes, Ivani M.; Silva, Paula P. Nou; Sordi, Gian Maria A.A.; Carneiro, Janete C.G.G.

    2011-01-01

    This paper has an objective to perform a radiometric survey at a hemodynamic service. Besides, it was intended to evaluate the effective dose of health professionals and to provide data which can contribute with minimization of exposures during the realization of hemodynamic procedure. The radiometric survey was realized in the real environment of work simulating the conditions of a hemodynamic study with a ionization chamber

  20. High frame-rate MR-guided near-infrared tomography system to monitor breast hemodynamics

    Science.gov (United States)

    Li, Zhiqiu; Jiang, Shudong; Krishnaswamy, Venkataramanan; Davis, Scott C.; Srinivasan, Subhadra; Paulsen, Keith D.; Pogue, Brian W.

    2011-02-01

    A near-infrared (NIR) tomography system with spectral-encoded sources at two wavelength bands was built to quantify the temporal contrast at 20 Hz bandwidth, while imaging breast tissue. The NIR system was integrated with a magnetic resonance (MR) machine through a custom breast coil interface, and both NIR data and MR images were acquired simultaneously. MR images provided breast tissue structural information for NIR reconstruction. Acquisition of finger pulse oximeter (PO) plethysmogram was synchronized with the NIR system in the experiment to offer a frequency-locked reference. The recovered absorption coefficients of the breast at two wavelengths showed identical temporal frequency as the PO output, proving this multi-modality design can recover the small pulsatile variation of absorption property in breast tissue related to the heartbeat. And it also showed the system's ability on novel contrast imaging of fast flow signals in deep tissue.

  1. Reduced baroreflex sensitivity in alcoholic cirrhosis: relations to hemodynamics and humoral systems

    DEFF Research Database (Denmark)

    Møller, Søren; Iversen, Jens S; Henriksen, Jens H

    2007-01-01

    In cirrhosis, arterial vasodilatation leads to central hypovolemia and activation of the sympathetic nervous and renin-angiotensin-aldosterone systems. As the liver disease and circulatory dysfunction may affect baroreflex sensitivity (BRS), we assessed BRS in a large group of patients with cirrh...

  2. [Effect adrenaline and ephedrine against a background of aminazine on systemic, cerebral and extracerebral hemodynamics].

    Science.gov (United States)

    Trofimenko, S P; Gaevoĭ, M D; Zaĭtsev, A A; Mel'kumov, R V; Em, M A

    1978-01-01

    Experiments with anesthetized cats demonstrated chlorpromazine (2 mg/kg) to pervert the vasopressor action of adrenaline (5 mkg/kg) and ephedrine (2 mg/kg) on the systemic arterial pressure, cerebral and extracerebral tonicity of the vessels. The authors believe that with chlorpromazine pretreatment the adrenomimetics produce a selective stimulation of the beta-adrenergic receptors, this accounting for the observed depressor effect.

  3. Numerical Simulation of Hemodynamic and Physiological Responses of Human Cardiovascular and Respiratory System under Drugs Administration

    Czech Academy of Sciences Publication Activity Database

    Převorovská, Světlana; Maršík, František

    2004-01-01

    Roč. 4, č. 4 (2004), s. 295-304 ISSN 1567-8822 R&D Projects: GA ČR(CZ) GA106/03/1073; GA ČR(CZ) GA106/03/0958 Institutional research plan: CEZ:AV0Z2076919 Keywords : human cardiovascular and respiratory system * baroreflex and chemoreflex control * physiologically based pharmacokinetic model Subject RIV: BK - Fluid Dynamics

  4. Deranged Wnt signaling is frequent in hereditary nonpolyposis colorectal cancer

    DEFF Research Database (Denmark)

    Isinger-Ekstrand, Anna; Therkildsen, Christina; Bernstein, Inge

    2011-01-01

    The Wnt signaling pathway is frequently deranged in colorectal cancer and is a key target for future preventive and therapeutic approaches. Colorectal cancers associated with the hereditary nonpolyposis colorectal cancer (HNPCC) syndrome are characterized by wide-spread microsatellite instability......, but show few gross genomic alterations. We characterized expression of the Wnt signaling pathway markers β-catenin, E-cadherin, TCF-4, and PTEN using immunohistochemical staining in colorectal cancers from individuals with HNPCC. Reduced membranous staining for β-catenin was found in 64% and for E......% of the tumors. In summary, altered expression of target molecules in the Wnt signaling pathway was demonstrated in the vast majority of the HNPCC-associated tumors, which support deranged Wnt-signaling as a central tumorigenic mechanism also in MMR defective colorectal cancer....

  5. Deranged Wnt signaling is frequent in hereditary nonpolyposis colorectal cancer

    DEFF Research Database (Denmark)

    Isinger-Ekstrand, Anna; Therkildsen, Christina; Bernstein, Inge

    2011-01-01

    The Wnt signaling pathway is frequently deranged in colorectal cancer and is a key target for future preventive and therapeutic approaches. Colorectal cancers associated with the hereditary nonpolyposis colorectal cancer (HNPCC) syndrome are characterized by wide-spread microsatellite instability......, but show few gross genomic alterations. We characterized expression of the Wnt signaling pathway markers ß-catenin, E-cadherin, TCF-4, and PTEN using immunohistochemical staining in colorectal cancers from individuals with HNPCC. Reduced membranous staining for ß-catenin was found in 64% and for E......% of the tumors. In summary, altered expression of target molecules in the Wnt signaling pathway was demonstrated in the vast majority of the HNPCC-associated tumors, which support deranged Wnt-signaling as a central tumorigenic mechanism also in MMR defective colorectal cancer....

  6. RENAL AND SYSTEMIC HEMODYNAMIC-EFFECTS OF IBOPAMINE IN PATIENTS WITH MILD-TO-MODERATE CONGESTIVE-HEART-FAILURE

    NARCIS (Netherlands)

    LIEVERSE, AG; VANVELDHUISEN, DJ; SMIT, AJ; ZIJLSTRA, JG; MEIJER, S; REITSMA, WD; LIE, KI; GIRBES, ARJ

    To study the hemodynamic and renal effects of the orally (p.o.) active dopamine (DA) agonist ibopamine, we examined 10 patients with mild to moderate congestive heart failure (CHF), who were stable while treated with digoxin and diuretics. All patients were in New York Heart Association (NYHA)

  7. Hemodynamic gestational adaptation in bitches

    OpenAIRE

    Almeida, Vívian Tavares de; Uscategui, Ricardo Andres Ramirez; Silva, Priscila Del Aguila da; Avante, Michele Lopes; Simões, Ana Paula Rodrigues; Vicente, Wilter Ricardo Russiano

    2017-01-01

    ABSTRACT: Throughout pregnancy, maternal hemodynamic adaptation is needed to ensure proper uterine perfusion and fetal development. When the uteroplacental vascular system is formed, starting with reduced resistance to uterine arterial flow, this results in decreased total vascular resistance, an activation of neuroendocrine vasoactive peptides, an increase in circulating blood and changes in the cardiovascular system morphophysiology to respond to the increasing demands of uterine perfusion....

  8. Numerical reproduction of hemodynamics change by acupuncture on Taichong (LR-3 based on the lumped-parameter approximation model of the systemic arteries

    Directory of Open Access Journals (Sweden)

    Atsushi Shirai

    2015-09-01

    Conclusion: The present model has a potential to emulate hemodynamic change by acupuncture therapy by incorporating physiological correlation of stimulation of an acupoint and regulation of parameters that affect the hemodynamics.

  9. Numerical reproduction of hemodynamics change by acupuncture on Taichong (LR-3) based on the lumped-parameter approximation model of the systemic arteries.

    Science.gov (United States)

    Shirai, Atsushi; Suzuki, Takuya; Seki, Takashi

    2015-09-01

    The aim of this study was to develop a mathematical model of blood flow in the systemic circulation to emulate the change in hemodynamics by acupuncture therapy to elucidate the mechanism of the therapy. For this purpose, as a first step, a simple model of arterial blood flow was presented to reproduce previously reported change in the blood flow volume by the acupuncture needle stimulation of Taichong (LR-3). This model was based on the lumped-parameter approximation of arterial blood flow together with linear resistance of peripheral circulation. It has been reported that blood flow in the left arm was enhanced after the stimulation, yielding the peripheral vascular resistance-regulated blood flow dominated by the sympathetic nervous system. In addition to the peripheral resistance, another parameter that possibly regulates the blood flow is the cross-sectional area of the vessel. These two factors were changed to numerically examine their contributions to the blood flow based on the hypothesis that they could be changed by the stimulation. The numerical result was compared with the experimental result to confirm the validity of the hypothesis that the blood flow in the arm is regulated by the peripheral resistance. This model is extremely simple and the physical parameters introduced for the simulation were gleaned from different reports in the literature. It was demonstrated, however, that regulation of the peripheral resistance rather than of the cross-sectional area could reproduce the experimentally observed change in the blood flow. Moreover, the relationship between the changes in the flow volume and the systemic vascular resistance quantitatively matched the experimental data. The present model has a potential to emulate hemodynamic change by acupuncture therapy by incorporating physiological correlation of stimulation of an acupoint and regulation of parameters that affect the hemodynamics.

  10. How long does it take to treat a Derangement?

    DEFF Research Database (Denmark)

    Melbye, Martin; Nymand, Camilla; Balskilde, Troels

    2008-01-01

    to conservative management. Previous randomised controlled trials have reported clinically relevant outcomes for low back patients, following a two and eight week treatment programme. The purpose of this study is to track treatment duration for cervical and lumbar patients classified into the derangement syndrome......, functional restoration exercises and prophylactic instructions. A total of 66 lumbar and 26 cervical spine patients were included and treated for an average of 4.3 and 2.4 weeks respectively. Scores for pain, functional level and self efficacy improved significantly and to a clinically relevant extent...

  11. Evaluating the hemodynamical response of a cardiovascular system under support of a continuous flow left ventricular assist device via numerical modeling and simulations.

    Science.gov (United States)

    Bozkurt, Selim; Safak, Koray K

    2013-01-01

    Dilated cardiomyopathy is the most common type of the heart failure which can be characterized by impaired ventricular contractility. Mechanical circulatory support devices were introduced into practice for the heart failure patients to bridge the time between the decision to transplant and the actual transplantation which is not sufficient due to the state of donor organ supply. In this study, the hemodynamic response of a cardiovascular system that includes a dilated cardiomyopathic heart under support of a newly developed continuous flow left ventricular assist device--Heart Turcica Axial--was evaluated employing computer simulations. For the evaluation, a numerical model which describes the pressure-flow rate relations of Heart Turcica Axial, a cardiovascular system model describing the healthy and pathological hemodynamics, and a baroreflex model regulating the heart rate were used. Heart Turcica Axial was operated between 8000 rpm and 11,000 rpm speeds with 1000 rpm increments for assessing the pump performance and response of the cardiovascular system. The results also give an insight about the range of the possible operating speeds of Heart Turcica Axial in a clinical application. Based on the findings, operating speed of Heart Turcica Axial should be between 10,000 rpm and 11,000 rpm.

  12. Evaluating the Hemodynamical Response of a Cardiovascular System under Support of a Continuous Flow Left Ventricular Assist Device via Numerical Modeling and Simulations

    Science.gov (United States)

    Safak, Koray K.

    2013-01-01

    Dilated cardiomyopathy is the most common type of the heart failure which can be characterized by impaired ventricular contractility. Mechanical circulatory support devices were introduced into practice for the heart failure patients to bridge the time between the decision to transplant and the actual transplantation which is not sufficient due to the state of donor organ supply. In this study, the hemodynamic response of a cardiovascular system that includes a dilated cardiomyopathic heart under support of a newly developed continuous flow left ventricular assist device—Heart Turcica Axial—was evaluated employing computer simulations. For the evaluation, a numerical model which describes the pressure-flow rate relations of Heart Turcica Axial, a cardiovascular system model describing the healthy and pathological hemodynamics, and a baroreflex model regulating the heart rate were used. Heart Turcica Axial was operated between 8000 rpm and 11000 rpm speeds with 1000 rpm increments for assessing the pump performance and response of the cardiovascular system. The results also give an insight about the range of the possible operating speeds of Heart Turcica Axial in a clinical application. Based on the findings, operating speed of Heart Turcica Axial should be between 10000 rpm and 11000 rpm. PMID:24363780

  13. Central Hemodynamics and Microcirculation in Critical Conditions

    Directory of Open Access Journals (Sweden)

    A. A. Kosovskikh

    2013-01-01

    Full Text Available Objective: to compare central hemodynamic and microcirculatory changes in critical conditions caused by different factors and to reveal their possible differences for a further differentiated approach to intensive therapy. Subjects and methods. The study covered 16 subjects with severe concomitant injury (mean age 41.96±2.83 years and 19 patients with general purulent peritonitis (mean age 45.34±2.16 years. Their follow-up was 7 days. The central hemodynamics was estimated by transpulmonary thermodilution using a Pulsion PiCCO Plus system (Pulsion Medical Systems, Germany. The microcirculatory bed was evaluated by cutaneous laser Doppler flowmetry using a LAKK-02 capillary blood flow laser analyzer (LAZMA Research-and-Production Association, Russian Federation. Results. The pattern of central hemodynamic and microcirculatory disorders varies with the trigger that has led to a critical condition. Central hemodynamics should be stabilized to ensure the average level of tissue perfusion in victims with severe concomitant injury. In general purulent peritonitis, microcirculatory disorders may persist even if the macrohemodynamic parameters are normal. Conclusion. The macrohemodynamic and microcirculatory differences obtained during the study suggest that a complex of intensive therapy should be differentiated and, if the latter is used, it is necessary not only to be based on the central hemodynamics, but also to take into consideration functional changes in microcirculation. Key words: severe concomitant injury, general purulent peritonitis, micro-circulation, central hemodynamics, type of circulation.

  14. MRI STUDY OF TYPES AND INCIDENCE OF INTERNAL DERANGEMENTS OF TRAUMATIC KNEE JOINT

    Directory of Open Access Journals (Sweden)

    Bomidi Sudha Rani

    2016-12-01

    Full Text Available BACKGROUND MRI has been accepted as the best imaging modality for noninvasive evaluation of knee injuries and it has proved reliable, safe and offers advantages over diagnostic arthroscopy, which is currently regarded as the reference standard for the diagnosis of internal derangements of the knee. 1 METHODS AND MATERIALS A prospective study of fifty patients who underwent MRI for the diagnosis of internal derangement of knee was conducted between the period of January 2015 to January 2016 in Government General Hospital, Kakinada. All the patients with history of knee joint pain following trauma and clinically suspected to have meniscal and ligament tears are included in the study. Patients were evaluated using GE 1.5 T MRI machine with pulsar gradient system using a sensor extremity coil. RESULTS Commonest lesion detected in our study was ACL tear followed by medial meniscal tear and medial collateral ligament injury. The most common sign of cruciate ligament injury was hyperintensity in the ligament. Grade 3 was the most common grade of meniscal tear. CONCLUSION MRI is an excellent, noninvasive, radiation free imaging modality and is unique in its ability to evaluate the internal structure as well as soft tissue delineation. Many anatomical variants can mimic a tear on MRI. MRI is an excellent noninvasive modality for imaging the knee and helps in arriving at a correct anatomical diagnosis there by guiding further management of the patient.

  15. ProSeal Laryngeal Mask Airway Attenuates Systemic and Cerebral Hemodynamic Response During Awakening of Neurosurgical Patients: A Randomized Clinical Trial.

    Science.gov (United States)

    Perelló-Cerdà, Laura; Fàbregas, Neus; López, Ana M; Rios, José; Tercero, Javier; Carrero, Enrique; Hurtado, Paola; Hervías, Adriana; Gracia, Isabel; Caral, Luis; de Riva, Nicolás; Valero, Ricard

    2015-07-01

    Extubation and emergence from anesthesia may lead to systemic and cerebral hemodynamic changes that endanger neurosurgical patients. We aimed to compare systemic and cerebral hemodynamic variables and cough incidence in neurosurgery patients emerging from general anesthesia with the standard procedure (endotracheal tube [ETT] extubation) or after replacement of the ETT with a laryngeal mask airway (LMA). Forty-two patients undergoing supratentorial craniotomy under general anesthesia were included in a randomized open-label parallel trial. Patients were randomized (sealed envelopes labeled with software-generated randomized numbers) to awaken with the ETT in place or after its replacement with a ProSeal LMA. We recorded mean arterial pressure as the primary endpoint and heart rate, middle cerebral artery flow velocity, regional cerebral oxygen saturation, norepinephrine plasma concentrations, and coughing. No differences were found between groups at baseline. All hemodynamic variables increased significantly from baseline in both groups during emergence. The ETT group had significantly higher mean arterial pressure (11.9 mm Hg; 95% confidence interval [CI], 2.1-21.8 mm Hg) (P=0.017), heart rate (7.2 beats/min; 95% CI, 0.7-13.7 beats/min) (P=0.03), and rate-pressure product (1045.4; 95% CI, 440.8-1650) (P=0.001). Antihypertensive medication was administered to more ETT-group patients than LMA-group patients (9 [42.9%] vs. 3 [14.3%] patients, respectively; P=0.04). The percent increase in regional cerebral oxygen saturation was greater in the ETT group by 26.1% (95% CI, 9.1%-43.2%) (P=0.002), but no between-group differences were found in MCA flow velocity. Norepinephrine plasma concentrations rose in both groups between baseline and the end of emergence: LMA: from 87.5±7.1 to 125.6±17.3 pg/mL; and ETT: from 118.1±14.1 to 158.1±24.7 pg/mL (P=0.007). The differences between groups were not significant. The incidence of cough was higher in the ETT group (87

  16. MRI FINDINGS OF INTERNAL DERANGEMENT OF KNEE IN TRAUMA

    Directory of Open Access Journals (Sweden)

    Ravi Ningappa

    2015-02-01

    Full Text Available AIMS AND OBJECTIVES: 1. To evaluate ligament and meniscal injuries and secondary signs , using MRI . 2. To analyse the types and grades of the tears. MATERIALS AND METHODS : MR imaging studies of knee was performed in 200 patients, presenting to the department of radiodiagnosis, BMCRI from September - 2013 to September - 2014 with history of trauma and clinical suspicion of internal der angement of knee. Various sequences in coronal, sagittal and axial planes were obtained. RESULTS : Out of 200 patients evaluated , medial meniscus tear was the most common internal derangement. 94 patients showed medial meniscus tear and associated anterior cruciate ligament tear was found in 76 patients. Medial collateral ligament sprain was seen in 18 patients, lateral meniscus injury was seen in 26 patients, lateral collateral ligament injury was seen in 8 patients, posterior cruciate ligament injury was s een in 16 patients, 20 patients showed cartilage defect and 18 percent showed no internal derangement. Associated secondary signs such as bone contusions were seen in 60 individuals and minimal to moderate joint effusion was seen in 74 individuals. CONCLUS ION : MRI is an accurate, non - invasive modality in detecting ligament and meniscal injury of knee. It shows great capability in classifying them into types and grades. Special sequences are useful and should be included in the protocol.

  17. Hemodynamic Intervention of Cerebral Aneurysms

    Science.gov (United States)

    Meng, Hui

    2005-11-01

    Cerebral aneurysm is a pathological vascular response to hemodynamic stimuli. Endovascular treatment of cerebral aneurysms essentially alters the blood flow to stop them from continued growth and eventual rupture. Compared to surgical clipping, endovascular methods are minimally invasive and hence rapidly gaining popularity. However, they are not always effective with risks of aneurysm regrowth and various complications. We aim at developing a Virtual Intervention (VI) platform that allows: patient-specific flow calculation and risk prediction as well as recommendation of tailored intervention based on quantitative analysis. This is a lofty goal requiring advancement in three areas of research: (1). Advancement of image-based CFD; (2) Understanding the biological/pathological responses of tissue to hemodynamic factors in the context of cerebral aneurysms; and (3) Capability of designing and testing patient-specific endovascular devices. We have established CFD methodologies based on anatomical geometry obtained from 3D angiographic or CT images. To study the effect of hemodynamics on aneurysm development, we have created a canine model of a vascular bifurcation anastomosis to provide the hemodynamic environment similar to those in CA. Vascular remodeling was studied using histology and compared against the flow fields obtained from CFD. It was found that an intimal pad, similar to those frequently seen clinically, developed at the flow impingement site, bordering with an area of `groove' characteristic of an early stage of aneurysm, where the micro environment exhibits an elevated wall shear stresses. To further address the molecular mechanisms of the flow-mediated aneurysm pathology, we are also developing in vitro cell culture systems to complement the in vivo study. Our current effort in endovascular device development focuses on novel stents that alters the aneurysmal flow to promote thrombotic occlusion as well as favorable remodeling. Realization of an

  18. Availability of a remote online hemodynamic monitoring system during treatment in a private dental office for medically high-risk patients

    Directory of Open Access Journals (Sweden)

    Shinya Yamazaki

    2008-09-01

    Full Text Available Shinya Yamazaki, Hiroyoshi Kawaai, Shigeo Sasaki, Kazuhiro Shimamura, Hiroshi Segawa, Takahiro SaitoSpecial Care Department in Dentistry, Ohu University Dental Hospital, Koriyama city, Fukushima prefecture, JapanAbstract: The importance of systemic management to prevent accidents is increasing in dentistry because co-morbid illnesses in an aging society and invasive surgical procedures are increasing. In this prefecture, a new medical system called the remote online hemodynamic monitoring system (ROHMs was started in 2001. Eight private dental offices participated in this trial. When dental practitioners feel the risk of a dental procedure, they can contact via ROHMs to this hospital. Then, the hemodynamic data (blood pressure, heart rate, ECG, SpO2, and RPP of the patient in the clinic can be transmitted here via the internet, and the images and the voice can be transmitted as well. The availability of this system was assessed in 66 patients (98 cases. The most frequent complications were hypertension, heart disease, and diabetes mellitus. Systemic management included monitoring during the dental procedure (71.4%, checking vital signs after an interview (15.3%, and monitoring under sedation (13.3%. There were 35.7% of all cases where an unscheduled procedure was necessary for the systemic management. Based on a questionnaire, the majority of the patients felt relieved and safe. This system creates a situation where a specialist is almost present during the procedure. This system will provide significant assistance for future medical cooperation for risk management.Keywords: online, high-risk patient, dental treatment, medical cooperation, medical accident, risk management

  19. Adenylyl Cyclase Signaling in the Developing Chick Heart: The Deranging Effect of Antiarrhythmic Drugs

    Directory of Open Access Journals (Sweden)

    Lucie Hejnova

    2014-01-01

    Full Text Available The adenylyl cyclase (AC signaling system plays a crucial role in the regulation of cardiac contractility. Here we analyzed the key components of myocardial AC signaling in the developing chick embryo and assessed the impact of selected β-blocking agents on this system. Application of metoprolol and carvedilol, two commonly used β-blockers, at embryonic day (ED 8 significantly downregulated (by about 40% expression levels of AC5, the dominant cardiac AC isoform, and the amount of Gsα protein at ED9. Activity of AC stimulated by forskolin was also significantly reduced under these conditions. Interestingly, when administered at ED4, these drugs did not produce such profound changes in the myocardial AC signaling system, except for markedly increased expression of Giα protein. These data indicate that β-blocking agents can strongly derange AC signaling during the first half of embryonic heart development.

  20. Usefulness of PiCCO in the management of patients with delayed vasospasm after subarachnoid hemorrhage. From a viewpoint of systemic cardiovascular hemodynamics

    International Nuclear Information System (INIS)

    Takayanagi, Shunsaku; Sakamoto, Masayuki; Kamijoh, Koji

    2008-01-01

    Before the PiCCO system became available, patients with delayed vasospasm were treated in order to control circulating blood volume from the viewpoint of several systemic factors associated with pressure such as central venous pressure, pulmonary arterial wedged pressure, etc. Since, however, these factors are well-known to not always reflect the circulating blood volume excessive intravenous administration induces over-hydration in patients who are either aged and/or are experiencing symptomatic vasospasm, leading to serious conditions such as pulmonary edema and cardiac failure. The PiCCO system has enabled us to treat patients with symptomatic vasospasm by more precisely estimating circulating hemodynamics. Taking into account the data obtained from the PiCCO system, we discuss its advantages and disadvantages. Out of patients who underwent acute surgery from June 2006 to May 2007, a total of 18 patients with Fisher 3 in CT grading of SAH who were thought to be likely to suffer from cardiac failure or pulmonary edema were selected. The average age was 63.2. The number of patients of preoperative Hunt and Kosnik Grade II, III, IV and V was 3, 10, 3 and 2, respectively. Angiographic vasospasm was revealed in 10 patients, 7 of whom were symptomatic. The in- and out-put control in these 18 patients was executed using the PiCCO system. None showed clinical symptoms associated with cardiac failure or pulmonary edema. We conclude that the PiCCO system is very useful to control the systemic hemodynamics in the treatment of patients with delayed vasospasm. (author)

  1. Avoiding occlusal derangement in facial fractures: An evidence based approach

    Directory of Open Access Journals (Sweden)

    Derick Mendonca

    2013-01-01

    Full Text Available Facial fractures with occlusal derangement describe any fracture which directly or indirectly affects the occlusal relationship. Such fractures include dento-alveolar fractures in the maxilla and mandible, midface fractures - Le fort I, II, III and mandible fractures of the symphysis, parasymphysis, body, angle, and condyle. In some of these fractures, the fracture line runs through the dento-alveolar component whereas in others the fracture line is remote from the occlusal plane nevertheless altering the occlusion. The complications that could ensue from the management of maxillofacial fractures are predominantly iatrogenic, and therefore can be avoided if adequate care is exercised by the operating surgeon. This paper does not emphasize on complications arising from any particular technique in the management of maxillofacial fractures but rather discusses complications in general, irrespective of the technique used.

  2. Artificial sweeteners produce the counterintuitive effect of inducing metabolic derangements.

    Science.gov (United States)

    Swithers, Susan E

    2013-09-01

    The negative impact of consuming sugar-sweetened beverages on weight and other health outcomes has been increasingly recognized; therefore, many people have turned to high-intensity sweeteners like aspartame, sucralose, and saccharin as a way to reduce the risk of these consequences. However, accumulating evidence suggests that frequent consumers of these sugar substitutes may also be at increased risk of excessive weight gain, metabolic syndrome, type 2 diabetes, and cardiovascular disease. This paper discusses these findings and considers the hypothesis that consuming sweet-tasting but noncaloric or reduced-calorie food and beverages interferes with learned responses that normally contribute to glucose and energy homeostasis. Because of this interference, frequent consumption of high-intensity sweeteners may have the counterintuitive effect of inducing metabolic derangements. Copyright © 2013 Elsevier Ltd. All rights reserved.

  3. Cine MR imaging of internal derangements of the knee

    International Nuclear Information System (INIS)

    Niitsu, M.; Anno, I.; Ishikawa, N.; Akisada, M.; Fukubayashi, T.

    1990-01-01

    This paper assesses internal derangements of the knee joint by a new method of cine MR imaging. Cine MR imaging, involving cine acquisition of kinematic sagittal images during knee movement, was used to evaluate 51 symptomatic patients and 19 healthy subjects. Cine MR images of cruciate ligament fears showed disappearance of low-intensity bundles during knee movement, periodic appearance of joint fluid in the area of the ligament, and irregular tibial movement. Cine MR images of meniscal tears showed independent movement of meniscal fragments and periodic tear opening and closing. Twenty-seven of the 28 anterior cruciate ligament (ACL) tears confirmed arthroscopically were correctly identified with cine MR imaging, with a sensitivity of 96% and a specificity of 92%

  4. Prenatal androgen excess programs metabolic derangements in pubertal female rats.

    Science.gov (United States)

    Yan, Xiaonan; Dai, Xiaonan; Wang, Jing; Zhao, Nannan; Cui, Yugui; Liu, Jiayin

    2013-04-01

    Owing to the heterogeneity in the clinical symptoms of polycystic ovary syndrome (PCOS), the early pathophysiological mechanisms of PCOS remain unclear. Clinical, experimental, and genetic evidence supports an interaction between genetic susceptibility and the influence of maternal environment in the pathogenesis of PCOS. To determine whether prenatal androgen exposure induced PCOS-related metabolic derangements during pubertal development, we administrated 5α-dihydrotestosterone (DHT) in pregnant rats and observed their female offspring from postnatal 4 to 8 weeks. The prenatally androgenized (PNA) rats exhibited more numerous total follicles, cystic follicles, and atretic follicles than the controls. Fasting glucose, insulin, leptin levels, and homeostatic model assessment for insulin resistance were elevated in the PNA rats at the age of 5-8 weeks. Following intraperitoneal glucose tolerance tests, glucose and insulin levels did not differ between two groups; however, the PNA rats showed significantly higher 30- and 60-min glucose levels than the controls after insulin stimulation during 5-8 weeks. In addition, prenatal DHT treatment significantly decreased insulin-stimulated phosphorylation of AKT in the skeletal muscles of 6-week-old PNA rats. The abundance of IR substrate 1 (IRS1) and IRS2 was decreased in the skeletal muscles and liver after stimulation with insulin in the PNA group, whereas phosphorylation of insulin-signaling proteins was unaltered in the adipose tissue. These findings validate the contribution of prenatal androgen excess to metabolic derangements in pubertal female rats, and the impaired insulin signaling through IRS and AKT may result in the peripheral insulin resistance during pubertal development.

  5. Benign intracranial hypertension associated to blood coagulation derangements

    Directory of Open Access Journals (Sweden)

    Niglio Alferio

    2006-12-01

    Full Text Available Abstract Background Benign Intracranial Hypertension (BIH may be caused, at least in part, by intracranial sinus thrombosis. Thrombosis is normally due to derangements in blood coagulation cascade which may predispose to abnormal clotting activation or deficiency in natural inhibitors' control. The aim of the study is to examine the strength of the association between risk factors for thrombosis and BIH. Patients and methods The incidence of prothrombotic abnormalities among a randomly investigated cohort of 17 patients with BIH, was compared with 51 healthy subjects matched for sex, age, body mass index, height and social background. Results The number of subjects with protein C deficiency was significantly higher in patients than in controls (3 vs 1, p Increased plasma levels of prothrombin fragment 1+2, fibrinopeptide A (FPA, and PAI-1 were demonstrated in patients group (5.7 ± 1.15 nM vs 0.45 ± 0.35 nM; 8.7 ± 2.5 ng/mL vs 2.2 ± 1.25 ng/mL; 45.7 ± 12.5 ng/mL vs 8.5 ± 6.7 ng/mL, respectively; p Discussion In agreement with other authors our data suggest a state of hypercoagulability in BIH associated with gene polymorphisms. Our findings also showed that mutations in cardiovascular genes significantly discriminate subjects with a BIH history. The association between coagulation and gene derangements, usually regarded to as cryptogenic, may suggest a possible pathogenetic mechanism in BIH. So, a prothrombotic tendency may exist that would, at least in part, explain some cases of BIH. Although based on a small population, these findings raise the exciting possibility of using these haemostatic factors as markers for selecting high-risk subjects in BIH disease.

  6. Homocysteine, Liver Function Derangement and Brain Atrophy in Alcoholics.

    Science.gov (United States)

    Fernández-Rodríguez, Camino; González-Reimers, Emilio; Quintero-Platt, Geraldine; de la Vega-Prieto, María José; Pérez-Hernández, Onán; Martín-González, Candelaria; Espelosín-Ortega, Elisa; Romero-Acevedo, Lucía; Santolaria-Fernández, Francisco

    2016-11-01

    Hyperhomocysteinemia may be involved in the development of brain atrophy in alcoholics. Its pathogenesis is multifactorial. In the present study, we analyse the relationship between homocysteine levels and brain atrophy, and the relative weight of co-existing factors such as liver function impairment, the amount of ethanol consumed, serum vitamin B12, B6, and folic acid levels on homocysteine levels and brain alterations in alcoholic patients. We included 59 patients admitted to this hospital for major withdrawal symptoms and 24 controls. The mini-mental state examination test and a brain computed tomography (CT) scan were performed and several indices were calculated. Serum levels of homocysteine, folic acid, vitamin B6 and vitamin B12 were determined. Liver function was assessed by Child-Pugh score. The daily consumption of ethanol in grams per day and years of addiction were recorded. A total of 83.6% and 80% of the patients showed cerebellar or frontal atrophy, respectively. Patients showed altered values of brain indices, higher levels of homocysteine and vitamin B12, but lower levels of folic acid, compared with controls. Homocysteine, B12 and liver function variables showed significant correlations with brain CT indices. Multivariate analyses disclosed that Pugh's score, albumin and bilirubin were independently related to cerebellar atrophy, frontal atrophy, cella index or ventricular index. Serum vitamin B12 was the only factor independently related to Evans index. It was also related to cella index, but after bilirubin. Homocysteine levels were independently related to ventricular index, but after bilirubin. Vitamin B12 and homocysteine levels are higher among alcoholics. Liver function derangement, vitamin B12 and homocysteine are all independently related to brain atrophy, although not to cognitive alterations. Hyperhomocysteinemia has been described in alcoholics and may be related to brain atrophy, a reversible condition with an obscure pathogenesis

  7. [Evaluation of changes in hemodynamic parameters after the use of electronic nicotine delivery systems among regular cigarette smokers].

    Science.gov (United States)

    Czogała, Jan; Cholewiński, Mateusz; Kutek, Agnieszka; Zielińska-Danch, Wioleta

    2012-01-01

    A relatively new device, described by producers as a device to help smokers quit, nicotine inhaler is an electronic (e-cigarette). Its mission is to provide the body with small doses of nicotine behavior "ceremonial" burning product is not tested for efficacy and toxicity The aim of this study was to compare the effects of nicotine absorbed from cigarette conventional and electronic changes in systolic and diastolic blood pressure and heart rate. Because of the potential interaction of carbon monoxide contained in cigarette smoke and nicotine conventional to changes on the parameters is also going to examine changes in the concentration of carboxyhemoglobin after smoking cigarettes and using e-cigarettes. study group consisted of 42 people, including 21 women and 21 men aged from 18 to 62 years who declared daily cigarette smoking. In this study it was found that as a result of cigarette smoking are increasing all the analyzed conventional hemodynamic parameters, these increases probably normally associated with nicotine absorbed by the smoker with the smoke. It was also a clear increase in carboxyhemoglobin, which is associated with a high concentration of carbon monoxide in cigarette smoke. If you use the e-cigarettes tested were observed increases in diastolic blood pressure and pulse, but none of the parameters did not change significantly, indicating that either the use of e-cigarette by the respondents did not supply the body with absorbable nicotine or for the increase in haemodynamic parameters studied did not correspond only nicotine but also other smoke constituents that interact with nicotine to the smoker body as carbon monoxide.

  8. Magnetic resonance imaging for the internal derangement of the knee

    International Nuclear Information System (INIS)

    Obara, Noboru; Yamauchi, Kazunori; Ohyama, Naoki; Kura, Hideharu; Tokita, Fumio; Sasaki, Tetsuhito

    1990-01-01

    To assess the usefulness of magnetic resonance imaging (MRI) in the preoperative diagnosis of internal derangement of the knee, MRI findings of 44 knees were reviewed. Definitive diagnoses were made by arthroscopy or arthrotomy: posterior cruciate ligament failure (8 knees), anterior cruciate ligament failure (21), inner meniscus injury (16), and outer meniscus injury (13). T1- and T2-weighted images were obtained by using a 1.5-T superconducting Signa MRI unit. The diagnostic accuracy was 100% for posterior cruciate ligament failure and anterior cruciate ligament failure, 89% for inner meniscus injury, and 93% for outer meniscus injury, suggesting the great potential of MRI in the preoperative diagnosis. For anterior cruciate ligament failure, the diagnostic accuracy was even more increased by combined use of T1-weighted sagittal imaging and T2-weighted coronal imaging. False positive findings for meniscus disorder included rupture of the posterior segment of meniscus, especially in the cnemis end. Longitudinal fissure of the posterior segment of the outer meniscus was misdiagnosed as lacuna of the popliteal muscle tendon. (N.K.)

  9. Short term outcomes following clipping and coiling of ruptured intracranial aneurysms: does some of the benefit of coiling stem from less procedural impact on deranged physiology at presentation?

    Science.gov (United States)

    Mortimer, Alex M; Bradford, Celia; Steinfort, Brendan; Faulder, Ken; Assaad, Nazih; Harrington, Timothy

    2016-02-01

    Endovascular coiling (EVC) has been shown to yield superior clinical outcomes to surgical clipping (SC) in the treatment of ruptured cerebral aneurysms. The reasons for these differences remain obscure. We aimed to assess outcomes of EVC and SC relative to baseline physiological derangement. This was an exploratory analysis of prospectively collected trial data. Physiological derangement was assessed using the Acute Physiology and Chronic Health Evaluation II (APACHE II) scoring system. Other contributory variables such as age, World Federation of Neurosurgical Societies (WFNS) grade, and development of complications, including hydrocephalus and vasospasm, were included in the analysis. Clinical outcome was independently assessed at 90 days using the modified Rankin Scale (mRS). Hospital stay, ventilated days, and total norepinephrine dose were also used as secondary outcomes. Multivariate analysis was performed using binary logistic regression. EVC was performed in 69 patients and SC in 66 patients. More profound physiological derangement (APACHE II score >15) was the strongest predictor of poor outcome in the overall cohort (OR 17.80, 95% CI 4.78 to 66.21, p15; 59 patients), WFNS grade ≥4 (OR 6.74, 1.43 to 31.75) and SC (OR 6.33, 1.27 to 31.38) were significant predictors of poor outcome (pEVC patients in this subgroup. SC patients had significantly increased total norepinephrine dose, ventilated days, and hospital stay (p<0.05). More profound physiological derangement at baseline is a strong predictor of eventual poor outcome, and outcomes for patients with more profound baseline physiological derangement may be improved if undergoing a coiling procedure. Published by the BMJ Publishing Group Limited. For permission to use (where not already granted under a licence) please go to http://www.bmj.com/company/products-services/rights-and-licensing/

  10. MRI STUDY OF TYPES AND INCIDENCE OF INTERNAL DERANGEMENTS OF TRAUMATIC KNEE JOINT

    OpenAIRE

    Bomidi Sudha Rani; Kaki Radha Rani; Bonthu Anuradha; B. M. Hemalatha; Karri Sambasiva Rao; Pasam Kusumalatha

    2016-01-01

    BACKGROUND MRI has been accepted as the best imaging modality for noninvasive evaluation of knee injuries and it has proved reliable, safe and offers advantages over diagnostic arthroscopy, which is currently regarded as the reference standard for the diagnosis of internal derangements of the knee. 1 METHODS AND MATERIALS A prospective study of fifty patients who underwent MRI for the diagnosis of internal derangement of knee was conducted between the period of January ...

  11. Natriuretic peptides and cerebral hemodynamics

    DEFF Research Database (Denmark)

    Guo, Song; Barringer, Filippa; Zois, Nora Elisabeth

    2014-01-01

    in decompensated disease. In contrast, their biological effects on the cerebral hemodynamics are poorly understood. In this mini-review, we summarize the hemodynamic effects of the natriuretic peptides with a focus on the cerebral hemodynamics. In addition, we will discuss its potential implications in diseases...... where alteration of the cerebral hemodynamics plays a role such as migraine and acute brain injury including stroke. We conclude that a possible role of the peptides is feasible as evaluated from animal and in vitro studies, but more research is needed in humans to determine the precise response...

  12. Recurrent myocardial infarction: Mechanisms of free-floating adaptation and autonomic derangement in networked cardiac neural control.

    Science.gov (United States)

    Kember, Guy; Ardell, Jeffrey L; Shivkumar, Kalyanam; Armour, J Andrew

    2017-01-01

    The cardiac nervous system continuously controls cardiac function whether or not pathology is present. While myocardial infarction typically has a major and catastrophic impact, population studies have shown that longer-term risk for recurrent myocardial infarction and the related potential for sudden cardiac death depends mainly upon standard atherosclerotic variables and autonomic nervous system maladaptations. Investigative neurocardiology has demonstrated that autonomic control of cardiac function includes local circuit neurons for networked control within the peripheral nervous system. The structural and adaptive characteristics of such networked interactions define the dynamics and a new normal for cardiac control that results in the aftermath of recurrent myocardial infarction and/or unstable angina that may or may not precipitate autonomic derangement. These features are explored here via a mathematical model of cardiac regulation. A main observation is that the control environment during pathology is an extrapolation to a setting outside prior experience. Although global bounds guarantee stability, the resulting closed-loop dynamics exhibited while the network adapts during pathology are aptly described as 'free-floating' in order to emphasize their dependence upon details of the network structure. The totality of the results provide a mechanistic reasoning that validates the clinical practice of reducing sympathetic efferent neuronal tone while aggressively targeting autonomic derangement in the treatment of ischemic heart disease.

  13. Recurrent myocardial infarction: Mechanisms of free-floating adaptation and autonomic derangement in networked cardiac neural control.

    Directory of Open Access Journals (Sweden)

    Guy Kember

    Full Text Available The cardiac nervous system continuously controls cardiac function whether or not pathology is present. While myocardial infarction typically has a major and catastrophic impact, population studies have shown that longer-term risk for recurrent myocardial infarction and the related potential for sudden cardiac death depends mainly upon standard atherosclerotic variables and autonomic nervous system maladaptations. Investigative neurocardiology has demonstrated that autonomic control of cardiac function includes local circuit neurons for networked control within the peripheral nervous system. The structural and adaptive characteristics of such networked interactions define the dynamics and a new normal for cardiac control that results in the aftermath of recurrent myocardial infarction and/or unstable angina that may or may not precipitate autonomic derangement. These features are explored here via a mathematical model of cardiac regulation. A main observation is that the control environment during pathology is an extrapolation to a setting outside prior experience. Although global bounds guarantee stability, the resulting closed-loop dynamics exhibited while the network adapts during pathology are aptly described as 'free-floating' in order to emphasize their dependence upon details of the network structure. The totality of the results provide a mechanistic reasoning that validates the clinical practice of reducing sympathetic efferent neuronal tone while aggressively targeting autonomic derangement in the treatment of ischemic heart disease.

  14. The movement time analyser task investigated with functional near infrared spectroscopy: an ecologic approach for measuring hemodynamic response in the motor system.

    Science.gov (United States)

    Vasta, Roberta; Cerasa, Antonio; Gramigna, Vera; Augimeri, Antonio; Olivadese, Giuseppe; Pellegrino, Giovanni; Martino, Iolanda; Machado, Alexis; Cai, Zhengchen; Caracciolo, Manuela; Grova, Christophe; Quattrone, Aldo

    2017-04-01

    Movement time analyzer (MTA) is an objective instrument to evaluate the degree of motor impairment as well as to investigate the dopaminergic drug effect in Parkinson's disease patients. The aim of this study is to validate a new ecologic neuroimaging tool for quantifying MTA-related hemodynamic response of the cortical motor system by means of functional near-infrared spectroscopy (fNIRS). 11 right-handed healthy volunteers (six male and five female, age range 27-64 years) were studied with fNIRS and functional magnetic resonance imaging (fMRI) while performing MTA task for each hand. MTA performance was better for the dominant hand and younger participants. Both fNIRS and fMRI analyses revealed MTA-related increase of haemoglobin levels in the primary motor and premotor cortices contralateral to the moving hand. This response progressively increased with aging. These findings supported the translation of fNIRS-based MTA behavioural tool in clinical practice.

  15. The development of a combined b-mode, ARFI, and spectral Doppler ultrasound imaging system for investigating cardiovascular stiffness and hemodynamics

    Science.gov (United States)

    Doherty, Joshua R.; Dumont, Douglas M.; Trahey, Gregg E.

    2011-03-01

    The progression of atherosclerotic disease, caused by the formation of plaques within arteries, is a complex process believed to be a function of the localized mechanical properties and hemodynamic loading associated with the arterial wall. It is hypothesized that measurements of vascular stiffness and wall-shear rate (WSR) may provide important information regarding vascular remodeling, endothelial function, and the growth of soft-lipid filled plaques that could help a clinician better diagnose a patient's risk of clinical events such as stroke. To that end, the approach taken in this work was to combine conventional B-mode, Acoustic Radiation Force Impulse (ARFI), Shear Wave Elasticity Imaging (SWEI), and spectral Doppler techniques into a single imaging system capable of simultaneously measuring the tissue displacements and WSR throughout the cardiac cycle and over several heartbeats. Implemented on a conventional scanner, the carotid arteries of human subjects were scanned to demonstrate the initial in vivo feasibility of the method. Two non-invasive ultrasound based imaging methods, SAD-SWEI and SAD-Gated Imaging, were developed that measure ARF-induced on-axis tissue displacements, off-axis transverse wave velocities, and WSR throughout the cardiac cycle. Human carotid artery scans were performed in vivo on 5 healthy subjects. Statistical differences were observed in both on-axis proximal wall displacements and transverse wave velocities during diastole compared to systole.

  16. [POSITIVE END-EXPIRATORY PRESSURE (PEEP) INFLUENCES ON INTRACRANIAL PRESSURE, SYSTEMIC HEMODYNAMICS AND PULMONARY GAS EXCHANGE IN PATIENTS WITH INTRACRANIAl HEMORRHAGE IN CRITICAL STATE].

    Science.gov (United States)

    Solodov, A A; Petrikov, S S; Krylov, V V

    2016-01-01

    Positive end-expiratory pressure is one of the main parameters of respiratory support influencing the gas exchange. However, despite the number ofpositive effects, PEEP can compromise venous outflow from the cranial cavity, increased intracranial pressure, decreased venous return and cardiac output and, consequently, reduced blood pressure and cerebral perfusion. The article presents the results of a survey of 39 patients with intracranial hemorrhage in critical state, undergoing respiratory support with different levels of positive end-expiratory pressure. Increasing of PEEP to 15 cm H2O had no adverse effect on mean arterial pressure, heart rate and cerebral perfusion pressure and led only to an clinical insignificant increase (maximum on 2.4 +/- 5.1 mmHg) in intracranial pressure. The greatest hemodynamic changes were observed with increasing PEEP up to 20 cm H2O in patients with preserved compliance ofthe respiratory system. The instability of cerebral perfusion and intracranial pressure associated with a decrease in cardiac output and preload and the exhaustion of compensatory mechanism of peripheral vascular resistance. High levels of PEEP despite the trend towards Cstat reduction will not lead to an increase in the content of extravascular lung water Thus a gradual increase of PEEP to 15 cm H2O can be safe and effective method of improving pulmonary gas exchange in patients with intracranial hemorrhage in critical state.

  17. Cerebral hemodynamics in migraine

    DEFF Research Database (Denmark)

    Hachinski, V C; Olesen, Jes; Norris, J W

    1977-01-01

    Clinical and angiographic findings in migraine are briefly reviewed in relation to cerebral hemodynamic changes shown by regional cerebral blood flow (rCBF) studies. Three cases of migraine studied by the intracarotid xenon 133 method during attacks are reported. In classic migraine, with typical...... prodromal symptoms, a decrease in cerebral blood flow has been demonstrated during the aura. Occasionally, this flow decrease persists during the headache phase. In common migraine, where such prodromata are not seen, a flow decrease has not been demonstrated. During the headache phase of both types...... of migraine, rCBF has usually been found to be normal or in the high range of normal values. The high values may represent postischemic hyperemia, but are probably more frequently secondary to arousal caused by pain. Thus, during the headache phase rCBF may be subnormal, normal or high. These findings do...

  18. SU-E-J-197: A Novel Optical Interstitial Fiber Spectroscopic System for Real-Time Tissue Micro-Vascular Hemodynamics Monitoring.

    Science.gov (United States)

    Zhao, D; Campos, D; Yan, Y; Kimple, R; Jacques, S; van der Kogel, A; Kissick, M

    2012-06-01

    To demonstrate a novel interstitial optical fiber spectroscopic system, based on diffuse optical spectroscopies with spectral fitting, for the simultaneous monitoring of tumor blood volume and oxygen tension. The technique provides real-time, minimally-invasive and quantification of tissue micro-vascular hemodynamics. An optical fiber prototype probe characterizesthe optical transport in tissue between two large Numerical Aperture (NA) fibers of 200μm core diameter (BFH37-200, ThorLabs) spaced 3-mm apart. Two 21-Ga medical needles are used to protect fiber ends and to facilitate tissue penetration with minimum local blunt trauma in nude mice with xenografts. A 20W white light source (HL-2000-HP, Ocean Optics) is coupled to one fiber with SMA adapter. The other fiber is used to collect light, which is coupled into the spectrometer (QE65000 with Spectrasuite Operating software and OmniDriver, Ocean Optics). The wavelength response of the probe depends on the wavelength dependence of the light source, and of the light signal collection that includes considerable scatter, modeled with Monte-Carlo techniques (S. Jacques 2010 J. of Innov. Opt. Health Sci. 2 123-9). Measured spectra of tissue are normalized by a measured spectrum of a white standard, yielding the transmission spectrum. A head-and-neck xenograft on the flank of a live mouse is used for development. The optical fiber probe delivers and collects light at an arbitrary depth in the tumor. By spectral fitting of the measured transmission spectrum, an analysis of blood volume and oxygen tension is obtained from the fitting parameters in real time. A newly developed optical fiber spectroscopic system with an optical fiber probe takes spectroscopic techniques to a much deeper level in a tumor, which has potential applications for real-time monitoring hypoxic cell population dynamics for an eventual adaptive therapy metric of particular use in hypofractionated radiotherapy. © 2012 American Association of

  19. Effect of large fundal varices on changes in gastric mucosal hemodynamics after endoscopic variceal ligation.

    Science.gov (United States)

    Tayama, C; Iwao, T; Oho, K; Toyonaga, A; Tanikawa, K

    1998-01-01

    aggravation of PHG after EVL is due to congestion of the gastric mucosal circulation. The presence of large fundal varices plays a protective role in the development of EVL-induced gastric mucosal hemodynamic derangement.

  20. Occupational dosimetry in real time hemodynamic rooms. utility of the system Dose-aware as a training tool

    International Nuclear Information System (INIS)

    Pinto Monedero, M.; Rodriguez Cobo, C.; Pifarre Martinez, X.; Ruiz Martin, J.; Barros Candelero, J. M.; Goicolea Ruigomez, J.; Diaz Blaires, G.; Garcia Lunar

    2014-01-01

    This paper presents the results from a study in a real time dosimetry system used in the catheter laboratory room of our center. The objective was to know the occupational doses per procedure, on the one hand, and, on the other hand, to evaluate its utility as a learning tool for radiation protection purposes with the simultaneous video recording of the interventions. 83 diagnostic and therapeutic procedures were analyzed, and an average dose per procedure of 0,37 μSv and 0,10 μSv for the main cardiologist and nurse were obtained, respectively. 36 of these interventions were also recorded and the images were synchronized with the dosimetric information stored and the dosimetry system. The findings were presented to the interventional cardiology team in a learning session. They showed a high level of satisfaction with this new method of optimizing the occupational doses through a customized learning session. (Author)

  1. Assessment of hemodynamic changes in the systemic and pulmonary arterial circulation in patients with cystic fibrosis using phase-contrast MRI

    Energy Technology Data Exchange (ETDEWEB)

    Ley, Sebastian; Eichinger, Monika [DKFZ, Department of Radiology (E010), Heidelberg (Germany); Johannes Gutenberg University, Department of Radiology, University Hospital Mainz, Mainz (Germany); Puderbach, Michael; Fink, Christian; Plathow, Christian; Kauczor, Hans-Ulrich [DKFZ, Department of Radiology (E010), Heidelberg (Germany); Teiner, Susanne [University of Heidelberg, Department of Pediatric Radiology, Heidelberg (Germany); Wiebel, Matthias [Thoraxklinik am Universitaetsklinikum, Department of Pulmonology, Heidelberg (Germany); Mueller, Frank-Michael [University of Heidelberg, Department of Pediatric Pulmonology, Heidelberg (Germany)

    2005-08-01

    Cystic fibrosis (CF) leads to disabling lung disease and pulmonary hypertension (PH). The goal of this study was to assess the hemodynamics in the systemic and pulmonary arterial circulation of patients with CF using MRI. Ten patients with CF and 15 healthy volunteers were examined (1.5-T MRI). Phase-contrast flow measurements were assessed in the ascending aorta, pulmonary trunc, and the left and right pulmonary arteries (PA), resulting in the following parameters: peak velocity (PV) (centimeters per second) velocity rise gradient (VRG), time to PV (milliseconds), and the average area (centimeters squared). The blood flow ratio between the right and left lungs and the bronchosystemic shunt were calculated. For the ascending aorta and pulmonary trunc no parameter was significantly different between both populations. In the right PA a significantly lower PV (p=0.001) and VRG (p=0.02) was found. In the left PA there was a significantly (p=0.007) lower PV but no significant (p=0.07) difference between the VRG. The areas of the right (p=0.08) and left (p=0.5) PA were not significantly enlarged. For the volunteers a linear increase of PV in both PA was found with age, while it decreased in patients with CF. The blood flow distribution (right/left lung) showed no significant (p=0.7) difference between the groups. There was a significantly (p<0.001) higher bronchosystemic shunt volume in patients with CF (1.3 l/min) than in volunteers (0.1 l/min). Magnetic resonance based flow measurements in the right and left PA showed first indications for early development of PH. The significant increase in bronchosystemic shunt volume might be indicative fo the extent of parenchymal changes. (orig.)

  2. Cerebral blood flow and systemic hemodynamics during exposure to 2 kPa CO2-300 kPa O2 in rats.

    Science.gov (United States)

    Bergø, G W; Tyssebotn, I

    1995-06-01

    Cerebral blood flow (CBF), systemic hemodynamics, and arterial blood gases were measured during control conditions and during and after exposure to either 300 kPa O2 (group 1) or 300 kPa O2 with 2 kPa CO2 (group 2) in awake rats. The respiratory frequency fell with no change of arterial PCO2 (PaCO2) in group 1, but in group 2, respiratory frequency and PaCO2 increased linearly. The cardiac output (CO) and heart rate (HR) fell and systolic arterial pressure (SAP) rose independent of PACO2. O2 breathing caused CBF to fall by 30% in group 1, whereas CBF rose linearly with the PaCO2 increase and pH decline in group 2. Regional CBF (rCBF) fell in group 1, whereas rCBF rose gradually in all regions in group 2, but the responses varied similarly in both groups. Regional brain O2 supply was unaltered in most areas. However, the O2 supply was possibly reduced in the brain stem in group 1 but markedly increased in group 2. After decompression, HR and SAP were high, whereas CO returned to its control value. CBF and all rCBF levels remained markedly elevated in group 2. In group 1, CBF returned to control levels. By contrast, rCBF and O2 delivery to brain stem regions remained subnormal. In conclusion, the O2-induced changes in HR, CO, and SAP were not influenced by hypercapnia. CBF and rCBF fell despite unaltered PaCO2, whereas hypercapnia prevented these declines. An uneven effect of O2 was observed on rCBF, most pronounced in brain stem regions, independent of the PaCO2. There was a prolonged suppression of O2 supply to brain stem regions both during and after the exposure to O2 in the absence of CO2.

  3. Quantitative MRI comparison of systemic hemodynamics in Mustard/Senning repaired patients and healthy volunteers at rest

    International Nuclear Information System (INIS)

    Laffon, Eric; Jimenez, Maria; Choussat, Alain; Latrabe, Valerie; Ducassou, Dominique; Marthan, Roger; Laurent, Francois

    2004-01-01

    The purpose of the present study was to non-invasively compare ascending aortic blood flow and cross-sectional area (CSA) variations vs time in Mustard or Senning repaired (MSR) patients against those of healthy volunteers at rest. Velocity-encoded MR imaging was performed in 10 male patients (age range 18-24 years, median age 20.5 years) late after a Mustard or Senning correction, and in 10 male healthy volunteers (age range 21-25 years, median age 22.5 years), at the upper part of the ascending aorta. Both aortic cross-sectional area (CSA) and blood-flow variations were recorded over a complete cardiac cycle, with a 30-ms time of resolution. The body-surface area (BSA), the mean CSA over the systolic phase, and the BSA-normalized systemic ventricle power and work were significantly lower in the patient series compared with those of the volunteer series. The BSA-normalized right ventricle (RV) power and work of MSR patients were equal to 87 and 83% on average of those of the left ventricle (LV) of healthy volunteers. We conclude that, at rest, the mechanical performance of the systemic RV in MSR patients is significantly lower than that of the LV in healthy volunteers. Furthermore, the significantly lower aortic CSA found in MSR patients than in healthy volunteers may reveal an increase in the vasomotor tone. (orig.)

  4. Hemodynamic and autonomic nervous system responses to mixed meal ingestion in healthy young and old subjects and dysautonomic patients with postprandial hypotension

    Science.gov (United States)

    Lipsitz, L. A.; Ryan, S. M.; Parker, J. A.; Freeman, R.; Wei, J. Y.; Goldberger, A. L.

    1993-01-01

    BACKGROUND. Although postprandial hypotension is a common cause of falls and syncope in elderly persons and in patients with autonomic insufficiency, the pathophysiology of this disorder remains unknown. METHODS AND RESULTS. We examined the hemodynamic, splanchnic blood pool, plasma norepinephrine (NE), and heart rate (HR) power spectra responses to a standardized 400-kcal mixed meal in 11 healthy young (age, 26 +/- 5 years) and nine healthy elderly (age, 80 +/- 5 years) subjects and 10 dysautonomic patients with symptomatic postprandial hypotension (age, 65 +/- 16 years). Cardiac and splanchnic blood pools were determined noninvasively by radionuclide scans, and forearm vascular resistance was determined using venous occlusion plethysmography. In healthy young and old subjects, splanchnic blood volume increased, but supine blood pressure remained unchanged after the meal. In both groups, HR increased and systemic vascular resistance remained stable. Forearm vascular resistance and cardiac index increased after the meal in elderly subjects, whereas these responses were highly variable and of smaller magnitude in the young. Young subjects demonstrated postprandial increases in low-frequency HR spectral power, representing cardiac sympatho-excitation, but plasma NE remained unchanged. In elderly subjects, plasma NE increased after the meal but without changes in the HR power spectrum. Patients with dysautonomia had a large postprandial decline in blood pressure associated with no change in forearm vascular resistance, a fall in systemic vascular resistance, and reduction in left ventricular end diastolic volume index. HR increased in these patients but without changes in plasma NE or the HR power spectrum. CONCLUSIONS. 1) In healthy elderly subjects, the maintenance of blood pressure homeostasis after food ingestion is associated with an increase in HR, forearm vascular resistance, cardiac index, and plasma NE. In both young and old, systemic vascular resistance is

  5. Strong association of MRI meniscal derangement and bone marrow lesions in knee osteoarthritis: data from the osteoarthritis initiative.

    Science.gov (United States)

    Lo, G H; Hunter, D J; Nevitt, M; Lynch, J; McAlindon, T E

    2009-06-01

    Meniscal damage is common in knee Osteoarthritis (OA) and predictive of structural progression, suggesting that their disruption plays a role in the development of OA. The bone marrow lesion (BML) is associated with pain and is a strong risk factor for structural progression. These lesions are associated with abnormal loading in a knee joint. Therefore, our hypothesis was that in those with symptomatic knee OA, large BMLs would be associated with ipsi-compartmental meniscal derangement. This was a cross-sectional study of a subsample of the Osteoarthritis Initiative where one set of magnetic resonance (MR) images from each participant was scored for tibiofemoral BMLs and meniscal derangement. We performed chi-squared tests comparing the prevalence of large BMLs in those with ipsi-compartmental meniscal derangement and those without. 160 Participants had a mean age of 61 (+/-9.9), mean BMI of 30.3 (+/-4.7) and 50% were female. 79% of medial and 39% of lateral menisci showed MRI (Magnetic Resonance Imaging) derangement. In those with medial meniscal MRI derangement, 44% had large medial BMLs while in those without medial meniscal derangement, 0% had large BMLs. Similar results were seen in the lateral compartment. Medial and lateral MRI meniscal derangement are highly prevalent in symptomatic knee OA and BMLs are highly associated with ipsi-compartmental MRI meniscal derangement.

  6. Hard and soft tissue imaging of the temporomandibular joint 30 years after diagnosis of osteoarthrosis and internal derangement

    NARCIS (Netherlands)

    deLeeuw, R; Boering, G; vanderKuijl, B; Stegenga, B

    1996-01-01

    Purpose: This article describes the clinical and imaging findings in the temporomandibular joints (TMJs) of patients 30 years after the initial diagnosis of osteoarthrosis and internal derangement. Patients and Methods: Fifty-five TMJs with a history of osteoarthrosis and internal derangement and 37

  7. Internal derangement as a predictor of provoked pain on mouth opening: A magnetic resonance imaging study.

    Science.gov (United States)

    Koh, Kwang-Joon; Park, Ha-Na; Kim, Kyoung-A

    2017-12-01

    This study investigated the relationship between pain and internal derangement in temporomandibular disorder (TMD) patients using magnetic resonance imaging (MRI). This study analyzed 356 TMD patients (712 temporomandibular joints [TMJs]). The inclusion criteria were the presence of spontaneous or provoked pain on one or both TMJs and having undergone MRI. The patients with provoked pain were divided into 3 groups: pain on palpation, pain on mouth opening, and pain on mastication. MRI was performed using a 1.5-T scanner. T1- and T2-weighted parasagittal and paracoronal images were obtained. According to the findings on the T1-weighted images, another 3 groups were created based on internal derangement: normal, disc displacement with reduction, and disc displacement without reduction. The MRI findings were independently interpreted by 2 experienced oral and maxillofacial radiologists at 2 different times. Statistical analysis was performed by the chi-square test using SPSS (version 12.0; SPSS Inc., Chicago, IL, USA). Provoked pain on mouth opening was found to be correlated with internal derangement in TMD patients ( P .05). These results suggest that internal derangement was a significant predictor of provoked pain on mouth opening.

  8. Central Hemodynamic Function in Miners with Thermal Injury

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    V. V. Moroz

    2008-01-01

    Full Text Available Objective: to study the specific features of central hemodynamic function in the acute phase of severe thermal injury (STI in miners who had a length of service of 10 years or more. Subjects and methods. A noninvasive study of central hemodynamics was conducted in 33 miners with severe thermal injury (a study group and 34 patients without a length of underground work who had the same condition (a control group. Both groups were matched by age and the nature and severity of thermal injuries. Central hemodynamics was evaluated by the following parameters: mean arterial blood, heart rate, stroke index (SI, cardiac index (CI, cardiac output (CO, specific vascular peripheral resistance (SVPR determined by Cubichek tetrapolar rheography. Results. The study indicated that on posttraumatic days 3—7, as compared with victims without a length of underground service, the miners had more pronounced central hemodynamic changes: decreases in CI, SI, and CO and an increase in SVPR. In the control group, from day 3, the hemodynamic changes were the following: increases in SI, SI, and CO and a decrease in SVPR. In the miners, the above features were attributable to the baseline central hemodynamic function. Conclusion. Thus, unlike the victims without a length of underground service, the miners with severe thermal injury develop more significant and prolonged central hemodynamic disorders. The detected differences during thermal injury are determined by the lowered reserve capacities of the cardiovascular system in miners due to the long-term exposure to poor working conditions, i. e. an underground service length of 10 years or more. Key words: thermal injury, miner, hemodynamics, type of circulation.

  9. Neonatal thymulin gene therapy prevents ovarian dysgenesis and attenuates reproductive derangements in nude female mice.

    Science.gov (United States)

    Reggiani, Paula C; Barbeito, Claudio G; Zuccolilli, Gustavo O; Cónsole, Gloria M; Flamini, Alicia M; Dardenne, Mireille; Goya, Rodolfo G

    2012-08-01

    Congenitally athymic (nude) female mice show severe ovarian dysgenesis after puberty, which seems to be consequential to a number of neuroendocrine derangements described in these mutants. Thus, considerable evidence suggests that thymulin, a thymic peptide, may be involved in thymus-pituitary communication. In order to clarify the relevance of thymulin for the maturation of the female reproductive system, we assessed at hypothalamic, pituitary, ovarian, and uterine level the preventive action of neonatal thymulin gene therapy (NTGT) on the changes that typically occur after puberty in congenitally athymic female mice. We injected (im) an adenoviral vector harboring a synthetic DNA sequence encoding a biologically active analog of thymulin, methionine-serum thymic factor, in newborn nude mice (which are thymulin deficient) and killed the animals at 70-71 d of age. NTGT in the athymic mice restored the serum thymulin levels. Morphometric analysis revealed that athymic nudes have reduced numbers of brain GnRH neurons and pituitary gonadotropic cells as compared with heterozygous controls. NTGT prevented these changes and also rescued the premature ovarian failure phenotype typically observed in athymic nude mice (marked reduction in the number of antral follicles and corpora lutea, increase in atretic follicles). Serum estrogen, but not progesterone, levels were low in athymic nudes, a reduction that was partially prevented by NTGT. Little to no morphological changes were observed in the endometrium of female nudes. The delay in the age of vaginal opening that occurs in athymic nudes was significantly prevented by NTGT. Our results suggest that thymulin plays a relevant physiologic role in the thymus-hypothalamo-pituitary-gonadal axis.

  10. Hemodynamic coherence and the rationale for monitoring the microcirculation.

    Science.gov (United States)

    Ince, Can

    2015-01-01

    This article presents a personal viewpoint of the shortcoming of conventional hemodynamic resuscitation procedures in achieving organ perfusion and tissue oxygenation following conditions of shock and cardiovascular compromise, and why it is important to monitor the microcirculation in such conditions. The article emphasizes that if resuscitation procedures are based on the correction of systemic variables, there must be coherence between the macrocirculation and microcirculation if systemic hemodynamic-driven resuscitation procedures are to be effective in correcting organ perfusion and oxygenation. However, in conditions of inflammation and infection, which often accompany states of shock, vascular regulation and compensatory mechanisms needed to sustain hemodynamic coherence are lost, and the regional circulation and microcirculation remain in shock. We identify four types of microcirculatory alterations underlying the loss of hemodynamic coherence: type 1, heterogeneous microcirculatory flow; type 2, reduced capillary density induced by hemodilution and anemia; type 3, microcirculatory flow reduction caused by vasoconstriction or tamponade; and type 4, tissue edema. These microcirculatory alterations can be observed at the bedside using direct visualization of the sublingual microcirculation with hand-held vital microscopes. Each of these alterations results in oxygen delivery limitation to the tissue cells despite the presence of normalized systemic hemodynamic variables. Based on these concepts, we propose how to optimize the volume of fluid to maximize the oxygen-carrying capacity of the microcirculation to transport oxygen to the tissues.

  11. [Hemodynamic changes in hypoglycemic shock].

    Science.gov (United States)

    Gutiérrez, C; Piza, R; Chousleb, A; Hidalgo, M A; Ortigosa, J L

    1977-01-01

    Severe hypoglycemia may be present in seriously ill patients; if it is not corrected opportunely a series of neuroendocrinal mechanisms take place aimed at correcting metabolic alterations. These mechanisms can produce hemodynamic alterations as well. Nine mongrel dogs were studied with continuous registration of: blood pressure, central venous pressure, cardiac frequency, respiratory frequency, electrocardiogram and first derivative (Dp/Dt). Six dogs received crystalline (fast acting) insuline intravenously (group 1). After hemodynamic changes were registered hypoglycemia was corrected with 50 per cent glucose solution. Complementary insuline doses were administered to three dogs (group 2); in this group hypoglycemia was not corrected. In group 1 during hypoglycemia there was an increase in blood pressure, central venous pressure, cardiac frequency, respiratory frequency and Dp/Dt, and changes in QT and T wave on the EKG; these changes were partially reversible after hypoglycemia was corrected. The above mentioned alterations persisted in group 2, breathing became irregular irregular and respiratory arrest supervened. It can be inferred that the hemodynamic response to hypoglycemia is predominantly adrenergic. The role of catecolamines, glucocorticoides, glucagon, insuline, cyclic AMP in metabolic and hemodynamic alterations consecutive to hypoglycemia are discussed.

  12. Diagnostic accuracy of low tesla MR imaging in the internal derangement of the knee

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    Kwon, Dae Ik; Ahn, Hyup; Kim, Jang Ho; Kim, Byung Young; Lee, Jong Gil [Fatima Hospital, Daegu (Korea, Republic of)

    1995-05-15

    This study is for the evaluation of low tesla(0.064T). MR imaging diagnostic accuracy in the internal derangement of the knee. We retrospectively analysed the MR images of 36 injured knees of 35 patients. The presence of tear was determined by arthroscopy or surgery in all cases. The specificity, accuracy, positive predictive value, negative predictive value of of low tesla MRI for the diagnosis of anterior cruciate ligament injury were 83%, 88%, 86%, 77%, 91%, for the posterior cruciate ligament 75%, 95%, 86%, 92%, 83%, for the medial collateral ligament 83%, 96%, 92%, 91%, 92%, for the lateral collateral ligament 67%, 97%, 94%, 67%, 97%, for the menisci 75%, 93%, 89%, 75%, 93%. The low tesla MRI is an accurate method in detection and evaluation of the internal derangement of the knee.

  13. Internal derangements of the temporomandibular joint: A review of the anatomy, diagnosis, and management

    Directory of Open Access Journals (Sweden)

    Andrew L Young

    2015-01-01

    Full Text Available Internal derangements of the temporomandibular joint are conditions in which the articular disc has become displaced from its original position the condylar head. Relevant anatomic structures and their functional relationships are briefly discussed. The displacement of the disc can result in numerous presentations, with the most common being disc displacement with reduction (with or without intermittent locking, and disc displacement without reduction (with or without limited opening. These are described in this article according to the standardized Diagnostic Criteria for Temporomandibular Disorders, as well as the less common posterior disc displacement. Appropriate management usually ranges from patient education and monitoring to splints, physical therapy, and medications. In rare and select cases, surgery may be necessary. However, in for the majority of internal derangements, the prognosis is good, particularly with conservative care.

  14. The effects of temporomandibular joint internal derangement and degenerative joint disease on tomographic and arthrotomographic images.

    Science.gov (United States)

    Brand, J W; Whinery, J G; Anderson, Q N; Keenan, K M

    1989-02-01

    In a blind study, 243 arthrograms were interpreted as showing normal disk position, anterior disk displacement with reduction, or anterior disk displacement without reduction. The presence or absence of a perforation of the posterior attachment or disk was recorded. Later, tomograms of the same patient were interpreted. The presence or absence of evidence of temporomandibular degenerative joint disease (TMDJD) was recorded. The condyle-to-fossa relationship was characterized as retropositioned or not retropositioned. O the 106 cases with tomographic evidence of TMDJD, 100 (94%) had arthrographic evidence of internal derangement (p less than 0.0001), whereas 47% of the cases with internal derangement (211) had evidence of TMDJD. Perforations were seen in 29 (27%) of the cases with degenerative joint disease and in none (0%) of the cases without TMDJD (p less than 0.001). In cases without TMDJD, 90% of the cases with internal derangement revealed condylar retropositioning (p less than 0.0001). With tomographic evidence of TMDJD present, the relationship between condylar position and disk position was not significant.

  15. Deranged Cardiac Metabolism and the Pathogenesis of Heart Failure

    Science.gov (United States)

    2016-01-01

    Activation of the neuro-hormonal system is a pathophysiological consequence of heart failure. Neuro-hormonal activation promotes metabolic changes, such as insulin resistance, and determines an increased use of non-carbohydrate substrates for energy production. Fasting blood ketone bodies as well as fat oxidation are increased in patients with heart failure, yielding a state of metabolic inefficiency. The net result is additional depletion of myocardial adenosine triphosphate, phosphocreatine and creatine kinase levels with further decreased efficiency of mechanical work. In this context, manipulation of cardiac energy metabolism by modification of substrate use by the failing heart has produced positive clinical results. The results of current research support the concept that shifting the energy substrate preference away from fatty acid metabolism and towards glucose metabolism could be an effective adjunctive treatment in patients with heart failure. The additional use of drugs able to partially inhibit fatty acids oxidation in patients with heart failure may therefore yield a significant protective effect for clinical symptoms and cardiac function improvement, and simultaneously ameliorate left ventricular remodelling. Certainly, to clarify the exact therapeutic role of metabolic therapy in heart failure, a large multicentre, randomised controlled trial should be performed. PMID:28785448

  16. Nutritional and Metabolic Derangements in Pancreatic Cancer and Pancreatic Resection

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    Taylor M. Gilliland

    2017-03-01

    Full Text Available Pancreatic cancer is an aggressive malignancy with a poor prognosis. The disease and its treatment can cause significant nutritional impairments that often adversely impact patient quality of life (QOL. The pancreas has both exocrine and endocrine functions and, in the setting of cancer, both systems may be affected. Pancreatic exocrine insufficiency (PEI manifests as weight loss and steatorrhea, while endocrine insufficiency may result in diabetes mellitus. Surgical resection, a central component of pancreatic cancer treatment, may induce or exacerbate these dysfunctions. Nutritional and metabolic dysfunctions in patients with pancreatic cancer lack characterization, and few guidelines exist for nutritional support in patients after surgical resection. We reviewed publications from the past two decades (1995–2016 addressing the nutritional and metabolic status of patients with pancreatic cancer, grouping them into status at the time of diagnosis, status at the time of resection, and status of nutritional support throughout the diagnosis and treatment of pancreatic cancer. Here, we summarize the results of these investigations and evaluate the effectiveness of various types of nutritional support in patients after pancreatectomy for pancreatic adenocarcinoma (PDAC. We outline the following conservative perioperative strategies to optimize patient outcomes and guide the care of these patients: (1 patients with albumin < 2.5 mg/dL or weight loss > 10% should postpone surgery and begin aggressive nutrition supplementation; (2 patients with albumin < 3 mg/dL or weight loss between 5% and 10% should have nutrition supplementation prior to surgery; (3 enteral nutrition (EN should be preferred as a nutritional intervention over total parenteral nutrition (TPN postoperatively; and, (4 a multidisciplinary approach should be used to allow for early detection of symptoms of endocrine and exocrine pancreatic insufficiency alongside implementation of

  17. Neonatal Hemodynamics: From Developmental Physiology to Comprehensive Monitoring

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    Sabine L. Vrancken

    2018-04-01

    Full Text Available Maintenance of neonatal circulatory homeostasis is a real challenge, due to the complex physiology during postnatal transition and the inherent immaturity of the cardiovascular system and other relevant organs. It is known that abnormal cardiovascular function during the neonatal period is associated with increased risk of severe morbidity and mortality. Understanding the functional and structural characteristics of the neonatal circulation is, therefore, essential, as therapeutic hemodynamic interventions should be based on the assumed underlying (pathophysiology. The clinical assessment of systemic blood flow (SBF by indirect parameters, such as blood pressure, capillary refill time, heart rate, urine output, and central-peripheral temperature difference is inaccurate. As blood pressure is no surrogate for SBF, information on cardiac output and systemic vascular resistance should be obtained in combination with an evaluation of end organ perfusion. Accurate and reliable hemodynamic monitoring systems are required to detect inadequate tissue perfusion and oxygenation at an early stage before this result in irreversible damage. Also, the hemodynamic response to the initiated treatment should be re-evaluated regularly as changes in cardiovascular function can occur quickly. New insights in the understanding of neonatal cardiovascular physiology are reviewed and several methods for current and future neonatal hemodynamic monitoring are discussed.

  18. Hemo-dynamics

    CERN Document Server

    Zamir, Mair

    2016-01-01

    Praise for Hemo-Dynamics: “This book provides an elegant and intuitive derivation of the fundamental mathematics underlying fluid flow, and then applies these in a straightforward way to pulsatile blood flow in all its complexity. One of the triumphs of the book is that Zamir succeeds in making essential concepts such as the Navier-Stokes equations completely accessible to any reader with a knowledge of basic calculus.  The author succeeds in conveying both the beauty of his subject matter, and his passion for the elegance and intricacies of fluid flow more generally.” Lindi Wahl, PhD, Professor of Applied Mathematics, The University of Western Ontario “Incredible, the figures alone are to die for… At first glance “Hemo-Dynamics” seems like a deep engineering and modeling dive into the mechanical properties of the cardiovascular system, blood, and how they interact to generate flow and pressure.  However, the text is laid out in a stepwise manner and I was especially impressed in the way that ...

  19. Effects of PaCO2 derangements on clinical outcomes after cerebral injury: A systematic review.

    Science.gov (United States)

    Roberts, Brian W; Karagiannis, Paul; Coletta, Michael; Kilgannon, J Hope; Chansky, Michael E; Trzeciak, Stephen

    2015-06-01

    Partial pressure of arterial carbon dioxide (PaCO2) is a major regulator of cerebral blood flow (CBF). Derangements in PaCO2 have been thought to worsen clinical outcomes after many forms of cerebral injury by altering CBF. Our aim was to systematically analyze the biomedical literature to determine the effects of PaCO2 derangements on clinical outcomes after cerebral injury. We performed a search of Cochrane Library, PUBMED, CINHAL, conference proceedings, and other sources using a comprehensive strategy. Study inclusion criteria were (1) human subjects; (2) cerebral injury; (3) mechanical ventilation post-injury; (4) measurement of PaCO2; and (5) comparison of a clinical outcome measure (e.g. mortality) between different PaCO2 exposures. We performed a qualitative analysis to collate and summarize effects of PaCO2 derangements according to the recommended methodology from the Cochrane Handbook. Seventeen studies involving different etiologies of cerebral injury (six traumatic brain injury, six post-cardiac arrest syndrome, two cerebral vascular accident, three neonatal ischemic encephalopathy) met all inclusion and no exclusion criteria. Three randomized control trials were identified and only one was considered a high quality study as per the Cochrane criteria for assessing risk of bias. In 13/17 (76%) studies examining hypocapnia, and 7/10 (70%) studies examining hypercapnia, the exposed group (hypercapnia or hypocapnia) was associated with poor clinical outcome. The majority of studies in this report found exposure to hypocapnia and hypercapnia after cerebral injury to be associated with poor clinical outcome. However, the optimal PaCO2 range associated with good clinical outcome remains unclear. Copyright © 2015 Elsevier Ireland Ltd. All rights reserved.

  20. A Case of Chronic Ethylene Glycol Intoxication Presenting without Classic Metabolic Derangements

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    Stephanie M. Toth-Manikowski

    2014-01-01

    Full Text Available Acute ethylene glycol ingestion classically presents with high anion gap acidosis, elevated osmolar gap, altered mental status, and acute renal failure. However, chronic ingestion of ethylene glycol is a challenging diagnosis that can present as acute kidney injury with subtle physical findings and without the classic metabolic derangements. We present a case of chronic ethylene glycol ingestion in a patient who presented with acute kidney injury and repeated denials of an exposure history. Kidney biopsy was critical to the elucidation of the cause of his worsening renal function.

  1. Cocaine-induced cardiovascular effects: lack of evidence for a central nervous system site of action based on hemodynamic studies with cocaine methiodide.

    Science.gov (United States)

    Dickerson, L W; Rodak, D J; Kuhn, F E; Wahlstrom, S K; Tessel, R E; Visner, M S; Schaer, G L; Gillis, R A

    1999-01-01

    It has been suggested that cocaine acts directly in the brain to enhance central sympathetic outflow. However, some studies suggested that the cardiovascular effects of cocaine are related to a peripheral action. To characterize further the site of cocaine's cardiovascular effect, we compared the hemodynamic effects of cocaine (2 mg/kg, i.v. bolus) with those observed after administration of an equimolar dose (2.62 mg/kg, i.v. bolus) of cocaine methiodide, a quaternary derivative of cocaine that does not penetrate the blood-brain barrier, by using sufentanil-sedated dogs. Cocaine produced significant (p < 0.05) increases in heart rate (+37+/-11 beats/min), mean arterial pressure (+55+/-11 mm Hg), left ventricular end-diastolic pressure (+5.3+/-1.0 mm Hg), and cardiac output (+2.4+/-0.9 L/min). Cocaine methiodide produced increases in heart rate (+57+/-11 beats/min), mean arterial pressure (+45+/-11 mm Hg), left ventricular end-diastolic pressure (+3.4+/-1.0 mm Hg), and cardiac output (1.1+/-0.9 L/min), which were not significantly different from those observed with cocaine. Because opiate sedation potentially might have attenuated central sympathetic outflow, we further confirmed the qualitative similarity of the actions of cocaine and cocaine methiodide on heart rate and blood pressure in unsedated, conscious dogs. Our data suggest that the cardiovascular effects of cocaine result primarily from a peripheral site of action.

  2. Conservative Management of Possible Meniscal Derangement Using the Mulligan Concept: A Case Report.

    Science.gov (United States)

    Sanchez, Belinda J; Baker, Russell T

    2017-12-01

    The purpose of this case study was to report on the immediate effects of the combined use of mobilizations with movement and the "squeeze" technique on a patient with knee stiffness, popping, and swelling. The patient presented with right knee stiffness, swelling, and a popping sensation of insidious onset. Clinical examination revealed pain with terminal knee extension and flexion, joint line tenderness, a positive Apley's compression test, and a positive Thessaly's test at 20° of knee flexion. A working diagnosis was established of a meniscal pathology with the differential diagnoses of meniscal derangement and synovial plica. The patient received 3 total treatments using the Mulligan concept over the course of 11 days. The treatments included the application of a tibia internal rotation mobilization with movement and the "squeeze" technique to the affected knee. Patient outcomes, including the Disablement in the Physically Active Scale, the Patient-Specific Functional Scale, and the Numeric Rating Scale for pain, were collected throughout the course of treatment. The patient reported a minimal clinically important difference on the Numeric Rating Scale for pain after each treatment and on all outcomes after the third treatment. The patient reported improvement on her follow-up visit 4 days after the third treatment; the results of a clinical exam and patient outcomes supported a complete discharge after 3 treatments. This patient responded favorably to use of the Mulligan concept as a manual therapy technique for the treatment of symptoms related to possible meniscal derangement.

  3. Acute hemodynamic response to vasodilators in primary pulmonary hypertension.

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    Kulkarni H

    1996-01-01

    Full Text Available Acute hemodynamic effects of high flow oxygen (O2 inhalation, sublingual isosorbide dinitrate (ISDN, intravenous aminophylline (AMN and sublingual nifedipine (NIF were studied in 32 patients with primary pulmonary hypertension (PPH. In 30 out of 32 patients the basal ratio of pulmonary to systemic vascular resistance (Rp/Rs was > 0.5 (mean = 0.77 +/- 0.20. Oxygen caused significant decrease in the mean resistance ratio to 0.68 +/- 0.20 (p = 0.005. ISDN, AMN and NIF caused increase in the resistance ratio to 0.79 +/- 0.26; 0.78 +/- 0.26; and 0.80 +/- 0.23 respectively. O2, ISDN, AMN and NIF caused a fall of Rp/Rs in 21 (65.6%, 10 (31.2%, 10(31.2% and 9(28.1% patients respectively. Thus, of the four drugs tested high flow O2 inhalation resulted in fall of Rp/Rs in two thirds of patients whereas ISDN, AMN and NIF caused a mean rise in Rp/Rs. One third of patients did respond acutely to the latter three drugs. Acute hemodynamic studies are useful before prescribing vasodilators in patients with PPH since more of the commonly used drugs like ISDN, AMN, NIF could have detrimental hemodynamic responses in some patients. However, great caution should be exercised before performing hemodynamic study as the procedure has definite mortality and morbidity.

  4. Hemodynamics and gas exchange during chest compressions in neonatal resuscitation.

    Directory of Open Access Journals (Sweden)

    Payam Vali

    Full Text Available Current knowledge about pulmonary/systemic hemodynamics and gas exchange during neonatal resuscitation in a model of transitioning fetal circulation with fetal shunts and fluid-filled alveoli is limited. Using a fetal lamb asphyxia model, we sought to determine whether hemodynamic or gas-exchange parameters predicted successful return of spontaneous circulation (ROSC.The umbilical cord was occluded in 22 lambs to induce asphyxial cardiac arrest. Following five minutes of asystole, resuscitation as per AHA-Neonatal Resuscitation Program guidelines was initiated. Hemodynamic parameters and serial arterial blood gases were assessed during resuscitation.ROSC occurred in 18 lambs (82% at a median (IQR time of 120 (105-180 seconds. There were no differences in hemodynamic parameters at baseline and at any given time point during resuscitation between the lambs that achieved ROSC and those that did not. Blood gases at arrest prior to resuscitation were comparable between groups. However, lambs that achieved ROSC had lower PaO2, higher PaCO2, and lower lactate during resuscitation. Increase in diastolic blood pressures induced by epinephrine in lambs that achieved ROSC (11 ±4 mmHg did not differ from those that were not resuscitated (10 ±6 mmHg. Low diastolic blood pressures were adequate to achieve ROSC.Hemodynamic parameters in a neonatal lamb asphyxia model with transitioning circulation did not predict success of ROSC. Lactic acidosis, higher PaO2 and lower PaCO2 observed in the lambs that did not achieve ROSC may represent a state of inadequate tissue perfusion and/or mitochondrial dysfunction.

  5. A clinical and radiological study on the internal derangement of TMJ

    International Nuclear Information System (INIS)

    Han, Won Jeong; Kim, Eun Kyung

    1992-01-01

    Internal derangement of the temporomandibular joint can be defined an abnormal relationships of the meniscus relative to the mandibular condyle, articular fossa and dminence. This may cause variable mandibular dysfunctions and pain. For diagnosis, arthrography, computed tomography and amgnetic resonance imaging are used. In this study, the author reviewed 98 TMJs of 88 patients who were diagnosed as internal derangement through inferior joint space arthrography at the department of Oral and Maxillofacial Radiology, Dental Hospital, Dankook university through 1986 to 1992. 98 TMJs consisting of 30 disc displacement with reduction, 48 disc displacement without reduction and 20 perforation were studied about clinical and radiological findings. The results were as follows: 1. Internal derangement was found most frequently in the 2nd, 3rd decades and the average age of perforation was higher than that of disc displacement with higher than that of disc displacement with reduction. The sexual predilection was 2 times higher in females. 2. The most frequent chief complaints were TMJ sound in disc displacement with reduction, pain and limitation of mouth opening in disc displacement without reduction and pain in perforation. The duration of the chief complaints was longer in disc displacement with reduction with than in perforation and disc displacement without reduction. 3. Reciprocal click was the most frequently TMJ sound in disc displacement with reduction. History of joint sound in disc displacement without reduction an crepitus in perforation was the most frequent one. 4. The average maximum opening was 45.4 mm in disc displacement with reduction, 31.4 mm in disc displacement without reduction and 33.8 mm in perforation. 5. In the centric occlusion, posterior condylar position was the most frequent in disc displacement with reduction. Posterior and concentric condylar position was frequent in disc displacement without reduction, concentric and anterior condylar

  6. Hemodynamic effects of ventricular defibrillation

    Science.gov (United States)

    Pansegrau, Donald G.; Abboud, François M.

    1970-01-01

    Hemodynamic responses to ventricular defibrillation were studied in anesthetized dogs. Observations were made on arterial, right atrial and left ventricular end-diastolic pressures, on cardiac output (dye dilution), heart rate, and right atrial electrocardiogram. Ventricular fibrillation was induced electrically with a bipolar electrode catheter placed in the right ventricle. Fibrillation was maintained for 15 or 30 sec and terminated with a 400 w sec capacitor discharge across the thoracic cage. Responses lasted 1-10 min after conversion and included a cholinergic and an adrenergic component. The cholinergic component was characterized by sinus bradycardia, periods of sinus arrest, atrioventricular block, and ventricular premature beats. The adrenergic component included increases in arterial pressure, in cardiac output, and in left ventricular stroke work at a time when left ventricular end-diastolic pressure was normal; there was no change in total peripheral resistance. The pH of arterial blood decreased slightly and pCO2 increased but pO2 and the concentration of lactate were unchanged. Bilateral vagotomy and intravenous administration of atropine blocked the cholinergic component, unmasked a sinus tachycardia, and accentuated the adrenergic component of the response. The latter was blocked by intravenous administration of propranolol and phenoxybenzamine. These responses were related primarily to conversion of ventricular fibrillation rather than to the electrical discharge of countershock because countershock without ventricular fibrillation caused more transient and smaller responses than those observed with defibrillation: furthermore, the hemodynamic effects of defibrillation were augmented by prolongation of the duration of fibrillation. The results suggest that the cholinergic component of the response may be detrimental in that it favors spontaneous recurrence of fibrillation; on the other hand, the adrenergic component may be essential for conversion

  7. Hemodynamic Effects of Glucagon - A Literature Review.

    Science.gov (United States)

    Meidahl Petersen, Kasper; Bøgevig, Søren; Holst, Jens Juul; Knop, Filip Krag; Christensen, Mikkel Bring

    2018-03-13

    Glucagon's effects on hemodynamic parameters - most notably heart rate and cardiac contractility - are overlooked. The glucagon receptor is a central target in novel and anticipated type 2 diabetes therapies and hemodynamic consequences of glucagon signaling have therefore become increasingly important. In this review we summarize and evaluate published studies on glucagon pharmacology with focus on clinical hemodynamic effects in humans. PubMed, EMBASE and the Cochrane library were searched for clinical studies concerning hemodynamic effects of glucagon (no year restriction). Papers reporting effects of a defined glucagon dose on any hemodynamic parameter were included. Reference searches were conducted in retrieved articles. Hemodynamic effects of glucagon have been investigated mainly in cohort-studies of heart failure patients receiving large glucagon bolus injections. The identified studies had shortcomings related to restricted patient groups, lack of a control group, randomization or blinding. We identified no properly conducted randomized clinical trials. The majority of human studies report stimulating effects of pharmacological glucagon doses on heart rate, cardiac contractility and blood pressure. The effects were characterized by short duration, inter-individual variation and rapid desensitization. Some studies reported no measurable effects of glucagon. The level of evidence regarding hemodynamic effects of glucagon is low and observations in published studies are inconsistent. Actual effects, inter-individual variation, dose-response relationships and possible long-term effects of supra-physiological glucagon levels warrant further investigation.

  8. Bone Marrow Micro-Environment in Normal and Deranged Hematopoiesis: Opportunities for Regenerative Medicine and Therapies.

    Science.gov (United States)

    Sarkaria, Shawn M; Decker, Matthew; Ding, Lei

    2018-03-01

    Various cell types cooperate to create a highly organized and dynamic micro-environmental niche in the bone marrow. Over the past several years, the field has increasingly recognized the critical roles of the interplay between bone marrow environment and hematopoietic cells in normal and deranged hematopoiesis. These advances rely on several new technologies that have allowed us to characterize the identity and roles of these niches in great detail. Here, we review the progress of the last several years, list some of the outstanding questions in the field and propose ways to target the diseased environment to better treat hematologic diseases. Understanding the extrinsic regulation by the niche will help boost hematopoiesis for regenerative medicine. Based on natural development of hematologic malignancies, we propose that combinatory targeting the niche and hematopoietic intrinsic mechanisms in early stages of hematopoietic malignancies may help eliminate minimal residual disease and have the highest efficacy. © 2018 WILEY Periodicals, Inc.

  9. Temporomandibular dysfunction: internal derangement associated with facial and/or mandibular asymmetry.

    Science.gov (United States)

    Maglione, Horacio O; de Zavaleta, Luis A; Laraudo, Jorge; Falisi, Giovanni; Fernandez, Fabiana

    2013-10-01

    The aim of this study was to observe the association between facial and/or mandibular asymmetry and internal derangement of the temporomandibular joint (TMJ) in patients with temporomandibular dysfunction (TMD). The sample consisted of 17 patients with facial and/or condylar-mandibular asymmetry who had signs and symptoms of TMD. They were evaluated by means of clinical examination, panoramic radiography, nuclear magnetic resonance (NMR), and in some cases, computed tomography (CT) and scintigraphy. All patients with facial and/or condylar-mandibular asymmetry had TMJ disc displacement (DD). The results of this study suggest a possible association between facial and/or condylar-mandibular asymmetry and DD. Based on these findings, it is important to consider the need for treating this disorder, particularly in growing patients, in order to prevent the generation of asymmetry, which is very difficult to treat once it sets in.

  10. Comparison of MRI findings with clinical symptoms in temporomandibular joint internal derangement

    International Nuclear Information System (INIS)

    Kwon, Ki Jeong

    2005-01-01

    To determine the clinical correlation of magnetic resonance imaging (MRI) findings of temporomandibular joint internal derangements. The MR images of 150 TMJs in 75 patients were analyzed. The clinical symptoms were pain in the pre auricular area and masticatory muscles and TMJ sounds. There was a statistically significant relationship between the MRI diagnoses of different types of disc displacements and clinical findings of pain, clicking, and crepitus. The risk of TMJ pain was increased when the disc displacement without reduction occurred at the same time in combination with the osteoarthrosis and effusion. Regardless of the results, the data indicate that each of these MR imaging variables may not be regarded as the unique and dominant factor in defining TMJ pain occurrence.

  11. A derangement of the brain wound healing process may cause some cases of Alzheimer's disease.

    Science.gov (United States)

    Lehrer, Steven; Rheinstein, Peter H

    2016-08-01

    A derangement of brain wound healing may cause some cases of Alzheimer's disease. Wound healing, a highly complex process, has four stages: hemostasis, inflammation, repair, and remodeling. Hemostasis and the initial phases of inflammation in brain tissue are typical of all vascularized tissue, such as skin. However, distinct differences arise in brain tissue during the later stages of inflammation, repair, and remodeling, and closely parallel the changes of Alzheimer's disease. Our hypothesis -- Alzheimer's disease is brain wound healing gone awry at least in some cases -- could be tested by measuring progression with biomarkers for the four stages of wound healing in humans or appropriate animal models. Autopsy studies might be done. Chronic traumatic encephalopathy might also result from the brain wound healing process.

  12. Reactive arthritis in relation to internal derangements of the temporomandibular joint: a case control study.

    Science.gov (United States)

    Lund, Bodil; Holmlund, Anders; Wretlind, Bengt; Jalal, Shah; Rosén, Annika

    2015-09-01

    The aim of this study was to find out if reactive arthritis was involved in the aetiology of chronic closed lock of the temporomandibular joint (TMJ) by looking for bacterial antigens in the synovial membrane of the TMJ, and by studying the antibody serology and carriage of human leucocyte antigen (HLA) B27 in patients with chronic closed lock. Patients with reciprocal clicking and healthy subjects acted as controls. We studied a total of 43 consecutive patients, 15 with chronic closed lock, 13 with reciprocal clicking, and 15 healthy controls with no internal derangements of the TMJ. Venous blood samples were collected from all subjects for measurement of concentrations of HLA tissue antigen and serology against Chlamydia trachomatis, Yersinia enterocolitica, Salmonella spp., Campylobacter jejuni, and Mycoplasma pneumoniae. Samples of synovial tissue from patients with closed lock and reciprocal clicking were obtained during discectomy and divided into two pieces, the first of which was tested by strand displacement amplification for the presence of C trachomatis, and the second of which was analysed for the presence of species-specific bacterial DNA using 16s rRNA pan-polymerase chain reaction (PCR). There were no significant differences between the groups in the incidence of antibodies against M pneumoniae, Salmonella spp. or Y enterocolitica. No patient had antibodies towards C trachomatis or C jejuni. We found no bacterial DNA in the synovial fluid from any patient. The HLA B27 antigen was present in 2/15 subjects in both the closed lock and control groups, and none in the reciprocal clicking group. In conclusion, reactive arthritis does not seem to be the mechanism of internal derangement of the TMJ. Copyright © 2015. Published by Elsevier Ltd.

  13. Effect of n-acetylcysteine on deranged renal functions in patient receiving non ionic radio contrast

    International Nuclear Information System (INIS)

    Faisal, A.; Kamal, M.

    2013-01-01

    Objective: To determine the effect of N-Acetylcysteine (NAC) on deranged renal functions in patients receiving non-ionic contrast. Study Design: Quasi- experimental study. Place and Duration of Study: The study was conducted in the Department of Radiology, DHQ Hospital Rawalpindi, RMC and Allied hospitals from August 2011 to January 2012. Methodology: Eighty consecutive patients with deranged renal function tests (RFTs) (creatinine level > 1.3 mg/dl and 50 mg/dl) were included in this study. These patients were advised to take at-least eight sachets of NAC to talling to 1,600 mg (one sachets is 200 mg) within two days with good hydration (6 to 8 glasses of water) prior to Contrast Enhanced Computer Tomographic (CECT) scan. After completion of NAC recommended dose, the RFTs are repeated to confirm the controlled range. The patients are allowed for CECT, if the serum urea level > 50 mg/dl (reference range 0-50 mg/dl) and serum creatinine level < 1.3 mg/dl (reference range 0.2-1.2 mg/dl). Results: The mean age of the patient is 53.98+-15.4 years. The use of NAC extensively improves the serum urea level of 73 out of 80 patients (91.3%) with a significance of 0.0001 to a normal level (<50 mg/dl). Similarly, serum creatinine level of 71 out of 80 patients (88.8%) with a significance of 0.0001 has an improved from reference range ( <=1. 2 mg/dl). Conclusion: Use of NAC resulted in improved serum urea and creatinine levels in the majority of patients. (author)

  14. Pharmacologic modulation of cerebral metabolic derangement and excitotoxicity in a porcine model of traumatic brain injury and hemorrhagic shock

    DEFF Research Database (Denmark)

    Hwabejire, John O; Jin, Guang; Imam, Ayesha M

    2013-01-01

    Cerebral metabolic derangement and excitotoxicity play critical roles in the evolution of traumatic brain injury (TBI). We have shown previously that treatment with large doses of valproic acid (VPA) decreases the size of brain lesion. The goal of this experiment was to determine whether...

  15. Invasive hemodynamic monitoring in the postoperative period of cardiac surgery

    Directory of Open Access Journals (Sweden)

    Desanka Dragosavac

    1999-08-01

    Full Text Available OBJETIVE: To assess the hemodynamic profile of cardiac surgery patients with circulatory instability in the early postoperative period (POP. METHODS: Over a two-year period, 306 patients underwent cardiac surgery. Thirty had hemodynamic instability in the early POP and were monitored with the Swan-Ganz catheter. The following parameters were evaluated: cardiac index (CI, systemic and pulmonary vascular resistance, pulmonary shunt, central venous pressure (CVP, pulmonary capillary wedge pressure (PCWP, oxygen delivery and consumption, use of vasoactive drugs and of circulatory support. RESULTS: Twenty patients had low cardiac index (CI, and 10 had normal or high CI. Systemic vascular resistance was decreased in 11 patients. There was no correlation between oxygen delivery (DO2 and consumption (VO2, p=0.42, and no correlation between CVP and PCWP, p=0.065. Pulmonary vascular resistance was decreased in 15 patients and the pulmonary shunt was increased in 19. Two patients with CI < 2L/min/m² received circulatory support. CONCLUSION: Patients in the POP of cardiac surgery frequently have a mixed shock due to the systemic inflammatory response syndrome (SIRS. Therefore, invasive hemodynamic monitoring is useful in handling blood volume, choice of vasoactive drugs, and indication for circulatory support.

  16. Hemodynamic Effects of Glucagon - A Literature Review

    DEFF Research Database (Denmark)

    Meidahl Petersen, Kasper; Bøgevig, Søren; Holst, Jens Juul

    2018-01-01

    Context: Glucagon's effects on hemodynamic parameters - most notably heart rate and cardiac contractility - are overlooked. The glucagon receptor is a central target in novel and anticipated type 2 diabetes therapies and hemodynamic consequences of glucagon signaling have therefore become increas...... is low and observations in published studies are inconsistent. Actual effects, inter-individual variation, dose-response relationships and possible long-term effects of supra-physiological glucagon levels warrant further investigation....

  17. Influence of ethanol-induced pulmonary embolism on hemodynamics in pigs

    Directory of Open Access Journals (Sweden)

    Shinsaku Yata

    2013-01-01

    Full Text Available Aims and Objectives: Ethanol is widely used for the embolization treatment of vascular malformations, but it can also cause serious complications such us pulmonary hypertension, cardiopulmonary collapse and death. The complications are considered secondary to pulmonary vasospasm and ethanol-induced sludge embolism, etc., We studied the hemodynamic effects of intravenous absolute ethanol injection and ethanol sludge injection in pigs. Materials and Methods: A total of 5 pigs underwent intravenous injection of ex vivo generated ethanol-induced sludge in which residual ethanol was removed (Group S and 4 pigs underwent intravenous injection of absolute ethanol (Group E. Hemodynamic parameters related to the pulmonary and systemic circulation were compared between the groups. Results: Transient pulmonary hypertension was observed in both groups and the hemodynamic changes were similar in both groups. Conclusions: Sludge can induce transient pulmonary hypertension or cardiopulmonary collapse, without ethanol and may be the mechanism by which ethanol induces its adverse hemodynamic effects.

  18. Hemodynamics driven cardiac valve morphogenesis.

    Science.gov (United States)

    Steed, Emily; Boselli, Francesco; Vermot, Julien

    2016-07-01

    Mechanical forces are instrumental to cardiovascular development and physiology. The heart beats approximately 2.6 billion times in a human lifetime and heart valves ensure that these contractions result in an efficient, unidirectional flow of the blood. Composed of endocardial cells (EdCs) and extracellular matrix (ECM), cardiac valves are among the most mechanically challenged structures of the body both during and after their development. Understanding how hemodynamic forces modulate cardiovascular function and morphogenesis is key to unraveling the relationship between normal and pathological cardiovascular development and physiology. Most valve diseases have their origins in embryogenesis, either as signs of abnormal developmental processes or the aberrant re-expression of fetal gene programs normally quiescent in adulthood. Here we review recent discoveries in the mechanobiology of cardiac valve development and introduce the latest technologies being developed in the zebrafish, including live cell imaging and optical technologies, as well as modeling approaches that are currently transforming this field. This article is part of a Special Issue entitled: Cardiomyocyte Biology: Integration of Developmental and Environmental Cues in the Heart edited by Marcus Schaub and Hughes Abriel. Copyright © 2015. Published by Elsevier B.V.

  19. Quantifying the abnormal hemodynamics of sickle cell anemia

    Science.gov (United States)

    Lei, Huan; Karniadakis, George

    2012-02-01

    Sickle red blood cells (SS-RBC) exhibit heterogeneous morphologies and abnormal hemodynamics in deoxygenated states. A multi-scale model for SS-RBC is developed based on the Dissipative Particle Dynamics (DPD) method. Different cell morphologies (sickle, granular, elongated shapes) typically observed in deoxygenated states are constructed and quantified by the Asphericity and Elliptical shape factors. The hemodynamics of SS-RBC suspensions is studied in both shear and pipe flow systems. The flow resistance obtained from both systems exhibits a larger value than the healthy blood flow due to the abnormal cell properties. Moreover, SS-RBCs exhibit abnormal adhesive interactions with both the vessel endothelium cells and the leukocytes. The effect of the abnormal adhesive interactions on the hemodynamics of sickle blood is investigated using the current model. It is found that both the SS-RBC - endothelium and the SS-RBC - leukocytes interactions, can potentially trigger the vicious ``sickling and entrapment'' cycles, resulting in vaso-occlusion phenomena widely observed in micro-circulation experiments.

  20. Wall Mechanical Properties and Hemodynamics of Unruptured Intracranial Aneurysms.

    Science.gov (United States)

    Cebral, J R; Duan, X; Chung, B J; Putman, C; Aziz, K; Robertson, A M

    2015-09-01

    Aneurysm progression and rupture is thought to be governed by progressive degradation and weakening of the wall in response to abnormal hemodynamics. Our goal was to investigate the relationship between the intra-aneurysmal hemodynamic conditions and wall mechanical properties in human aneurysms. A total of 8 unruptured aneurysms were analyzed. Computational fluid dynamics models were constructed from preoperative 3D rotational angiography images. The aneurysms were clipped, and the domes were resected and mechanically tested to failure with a uniaxial testing system under multiphoton microscopy. Linear regression analysis was performed to explore possible correlations between hemodynamic quantities and the failure characteristics and stiffness of the wall. The ultimate strain was correlated negatively to aneurysm inflow rate (P = .021), mean velocity (P = .025), and mean wall shear stress (P = .039). It was also correlated negatively to inflow concentration, oscillatory shear index, and measures of the complexity and instability of the flow; however, these trends did not reach statistical significance. The wall stiffness at high strains was correlated positively to inflow rate (P = .014), mean velocity (P = .008), inflow concentration (P = .04), flow instability (P = .006), flow complexity (P = .019), wall shear stress (P = .002), and oscillatory shear index (P = .004). In a study of 8 unruptured intracranial aneurysms, ultimate strain was correlated negatively with aneurysm inflow rate, mean velocity, and mean wall shear stress. Wall stiffness was correlated positively with aneurysm inflow rate, mean velocity, wall shear stress, flow complexity and stability, and oscillatory shear index. These trends and the impact of hemodynamics on wall structure and mechanical properties should be investigated further in larger studies. © 2015 by American Journal of Neuroradiology.

  1. Dynamic cerebral autoregulation measured with coherent hemodynamics spectroscopy (CHS)

    Science.gov (United States)

    Kainerstorfer, Jana M.; Sassaroli, Angelo; Tgavalekos, Kristen T.; Fantini, Sergio

    2015-03-01

    Coherent Hemodynamics Spectroscopy (CHS) is a novel technique for non-invasive measurements of local microcirculation quantities such as the capillary blood transit times and dynamic autoregulation. The basis of CHS is to measure, for instance with near-infrared spectroscopy (NIRS), peripheral coherent hemodynamic changes that are induced by controlled perturbations in the systemic mean arterial pressure (MAP). In this study, the MAP perturbation was induced by the fast release of two pneumatic cuffs placed around the subject's thighs after they were kept inflated (at 200 mmHg) for two minutes. The resulting transient changes in cerebral oxy- (O) and deoxy- (D) hemoglobin concentrations measured with NIRS on the prefrontal cortex are then described by a novel hemodynamic model, from which quantifiable parameters such as the capillary blood transit time and a cutoff frequency for cerebral autoregulation are obtained. We present results on eleven healthy volunteers in a protocol involving measurements during normal breathing and during hyperventilation, which is known to cause a hypocapnia-induced increase in cerebral autoregulation. The measured capillary transit time was unaffected by hyperventilation (normal breathing: 1.1±0.1 s; hyperventilation: 1.1±0.1 s), whereas the cutoff frequency of autoregulation, which increases for higher autoregulation efficiency, was indeed found to be significantly greater during hyperventilation (normal breathing: 0.017±0.002 Hz; hyperventilation: 0.034±0.005 Hz). These results provide a validation of local cerebral autoregulation measurements with the new technique of CHS.

  2. Hemodynamic and tubular changes induced by contrast media.

    Science.gov (United States)

    Caiazza, Antonella; Russo, Luigi; Sabbatini, Massimo; Russo, Domenico

    2014-01-01

    The incidence of acute kidney injury induced by contrast media (CI-AKI) is the third cause of AKI in hospitalized patients. Contrast media cause relevant alterations both in renal hemodynamics and in renal tubular cell function that lead to CI-AKI. The vasoconstriction of intrarenal vasculature is the main hemodynamic change induced by contrast media; the vasoconstriction is accompanied by a cascade of events leading to ischemia and reduction of glomerular filtration rate. Cytotoxicity of contrast media causes apoptosis of tubular cells with consequent formation of casts and worsening of ischemia. There is an interplay between the negative effects of contrast media on renal hemodynamics and on tubular cell function that leads to activation of renin-angiotensin system and increased production of reactive oxygen species (ROS) within the kidney. Production of ROS intensifies cellular hypoxia through endothelial dysfunction and alteration of mechanisms regulating tubular cells transport. The physiochemical characteristics of contrast media play a critical role in the incidence of CI-AKI. Guidelines suggest the use of either isoosmolar or low-osmolar contrast media rather than high-osmolar contrast media particularly in patients at increased risk of CI-AKI. Older age, presence of atherosclerosis, congestive heart failure, chronic renal disease, nephrotoxic drugs, and diuretics may multiply the risk of CI-AKI.

  3. A Novel Stretch Sensor to Measure Venous Hemodynamics

    Directory of Open Access Journals (Sweden)

    Syrpailyne Wankhar

    2018-07-01

    Full Text Available Chronic venous insufficiency is a debilitating condition causing varicose veins and venous ulcers. The pathophysiology includes reflux and venous obstruction. The diagnosis is often made by clinical examination and confirmed by Venous Doppler studies. Plethysmography helps to quantitatively examine the reflux and diagnose the burden of deep venous pathology to better understand venous hemodynamics, which is not elicited by venous duplex examination alone. However, most of these tests are qualitative, expensive, and not easily available. In this paper, we demonstrate the potential use of a novel stretch sensor in the assessment of venous hemodynamics during different maneuvers by measuring the change in calf circumference. We designed the stretch sensor by using semiconductor strain gauges pasted onto a small metal bar to form a load cell. The elastic and Velcro material attached to the load cell form a belt. It converts the change in limb circumference to a proportional tension (force of distension when placed around the calf muscle. We recorded the change in limb circumference from arrays of stretch sensors by using an in-house data acquisition system. We calculated the venous volume (VV, venous filling index (VFI, ejection fraction (EF and residual venous volume (RVV on two normal subjects and on two patients to assess venous hemodynamics. The values (VV > 60 ml, VFI 60%, RVV 2ml/s, EF 35% in patients were comparable to those reported in the literature.

  4. Radiographic changes of TMJ components with an advancement of TMJ internal derangement

    International Nuclear Information System (INIS)

    Kurita, Hiroshi

    2006-01-01

    Internal derangement (ID) of the temporomandibular joint (TMJ) relates to a mechanical and anatomical disturbance interfering with the smooth joint function. The ID usually develops in a benign and self-limiting fashion and does not always lead to progressing disorders. Radiographically visible degenerative changes occur with advancement of ID. It is thought that most of these changes closely correlate with the self-limiting nature of ID. In this report, a variety of radiographically visible degenerative changes were shown to develop with advancing ID. These changes, including a total and more anterior displacement of the TMJ disk, deviations in configuration of the TMJ disk, resorption of lateral pole of TMJ condyle, regression in horizontal size of the TMJ condyle, and flattening of the articular eminence, developed reflecting each other and might play an important role in an improvement of clinical signs and symptoms in the long run. It is also suggested that most of the acute and destructive radiographically visible degenerative changes were arrested or slowed in those patients whose symptoms and signs were successfully resolved or reduced. (author)

  5. Verification of a computational cardiovascular system model comparing the hemodynamics of a continuous flow to a synchronous valveless pulsatile flow left ventricular assist device

    Science.gov (United States)

    Gohean, Jeffrey R.; George, Mitchell J.; Pate, Thomas D.; Kurusz, Mark; Longoria, Raul G.; Smalling, Richard W.

    2012-01-01

    The purpose of this investigation is to utilize a computational model to compare a synchronized valveless pulsatile left ventricular assist device to continuous flow left ventricular assist devices at the same level of device flow, and to verify the model with in vivo porcine data. A dynamic system model of the human cardiovascular system was developed to simulate support of a healthy or failing native heart from a continuous flow left ventricular assist device or a synchronous, pulsatile, valveless, dual piston positive displacement pump. These results were compared to measurements made during in vivo porcine experiments. Results from the simulation model and from the in vivo counterpart show that the pulsatile pump provides higher cardiac output, left ventricular unloading, cardiac pulsatility, and aortic valve flow as compared to the continuous flow model at the same level of support. The dynamic system model developed for this investigation can effectively simulate human cardiovascular support by a synchronous pulsatile or continuous flow ventricular assist device. PMID:23438771

  6. Eating disorders should be considered in the differential diagnosis of patients presenting with acute kidney injury and electrolyte derangement

    OpenAIRE

    Talbot, Ben Edward Michael; Lawman, Sarah H A

    2014-01-01

    We present a case of a 40-year-old woman with a history of ongoing anorexia nervosa and bulimia nervosa who has required multiple admissions to hospital for management of acute kidney injury (AKI) and electrolyte derangement. This case is of interest as recent studies have highlighted the significant prevalence of disordered eating and the major public health implications this may have. We discuss the unusual finding of hypercalcaemia in this case and address the investigation and management ...

  7. A Derangement of the Brain Wound Healing Process May Cause Some Cases of Alzheimer’s Disease

    OpenAIRE

    Lehrer, Steven; Rheinstein, Peter H.

    2016-01-01

    A derangement of brain wound healing may cause some cases of Alzheimer’s disease. Wound healing, a highly complex process, has four stages: hemostasis, inflammation, repair, and remodeling. Hemostasis and the initial phases of inflammation in brain tissue are typical of all vascularized tissue, such as skin. However, distinct differences arise in brain tissue during the later stages of inflammation, repair, and remodeling, and closely parallel the changes of Alzheimer’s disease. Our hypothesi...

  8. A comparative study of mandibular movements with their MR images in patients with internal derangement of the TMJ

    International Nuclear Information System (INIS)

    Miyamoto, Satoshi; Ogawa, Takumi; Hosoda, Yutaka

    1993-01-01

    Thirty one patients with internal derangement of the TMJ and 12 subjects with normal TMJ were selected and their MR imaging and border movements of the mandible were recorded. In addition, the relationship between them were examined. In this study, the disk position and configuration in MR findings were classified as follows. Disk position: superior, anterior and anterolateral (medial and lateral were omitted), grade of anterior disk displacement (with and without reduction): slight, moderate and severe, disk configuration: biconcave, enlargement of posterior band, even thickness and biconvex. Border movements of the mandible were influenced not only by unilateral or bilateral interior derangement but also by with or without reduction of the disk. Border movements in patients with anterolateral disk displacement were more severely restricted than those with anterior disk displacement. Border movements were remarkably limited in patients with slight disk displacement, especially in unilateral cases with reduction of the disk. Border movements in patients with even thickness and biconvex types of disk configuration were a little restricted and rather similar to those of normal subjects. There was significant correlation between border movements and disk position and configuration. It means that measurement of the mandibular movements is very significant to diagnose the condition of internal derangements of the TMJ. (author)

  9. Cerebral hemodynamics: concepts of clinical importance

    Directory of Open Access Journals (Sweden)

    Edson Bor-Seng-Shu

    2012-05-01

    Full Text Available Cerebral hemodynamics and metabolism are frequently impaired in a wide range of neurological diseases, including traumatic brain injury and stroke, with several pathophysiological mechanisms of injury. The resultant uncoupling of cerebral blood flow and metabolism can trigger secondary brain lesions, particularly in early phases, consequently worsening the patient's outcome. Cerebral blood flow regulation is influenced by blood gas content, blood viscosity, body temperature, cardiac output, altitude, cerebrovascular autoregulation, and neurovascular coupling, mediated by chemical agents such as nitric oxide (NO, carbon monoxide (CO, eicosanoid products, oxygen-derived free radicals, endothelins, K+, H+, and adenosine. A better understanding of these factors is valuable for the management of neurocritical care patients. The assessment of both cerebral hemodynamics and metabolism in the acute phase of neurocritical care conditions may contribute to a more effective planning of therapeutic strategies for reducing secondary brain lesions. In this review, the authors have discussed concepts of cerebral hemodynamics, considering aspects of clinical importance.

  10. Systemic Metabolic Derangement, Pulmonary Effects, and Insulin Insufficiency Following Subchronic Ozone Exposure in Rats

    Data.gov (United States)

    U.S. Environmental Protection Agency — This data set includes individual animal data collected for various biological endpoints that are included in the manuscript. Miller DB, Snow SJ, Henriquez A,...

  11. Systemic Metabolic Derangement, Pulmonary Effects, and Insulin Insufficiency following subchronic ozone exposure in rats

    Science.gov (United States)

    Acute ozone exposure induces a classical stress response with elevated circulating stress hormones along with changes in glucose, protein and lipid metabolism in rats, with similar alterations in ozone-exposed humans. These stress-mediated changes over time have been linked to in...

  12. Systemic metabolic derangement, pulmonary effects, and insulin insufficiency following subchronic ozone exposure in rats

    International Nuclear Information System (INIS)

    Miller, Desinia B.; Snow, Samantha J.; Henriquez, Andres; Schladweiler, Mette C.; Ledbetter, Allen D.; Richards, Judy E.; Andrews, Debora L.; Kodavanti, Urmila P.

    2016-01-01

    Acute ozone exposure induces a classical stress response with elevated circulating stress hormones along with changes in glucose, protein and lipid metabolism in rats, with similar alterations in ozone-exposed humans. These stress-mediated changes over time have been linked to insulin resistance. We hypothesized that acute ozone-induced stress response and metabolic impairment would persist during subchronic episodic exposure and induce peripheral insulin resistance. Male Wistar Kyoto rats were exposed to air or 0.25 ppm or 1.00 ppm ozone, 5 h/day, 3 consecutive days/week (wk) for 13 wks. Pulmonary, metabolic, insulin signaling and stress endpoints were determined immediately after 13 wk or following a 1 wk recovery period (13 wk + 1 wk recovery). We show that episodic ozone exposure is associated with persistent pulmonary injury and inflammation, fasting hyperglycemia, glucose intolerance, as well as, elevated circulating adrenaline and cholesterol when measured at 13 wk, however, these responses were largely reversible following a 1 wk recovery. Moreover, the increases noted acutely after ozone exposure in non-esterified fatty acids and branched chain amino acid levels were not apparent following a subchronic exposure. Neither peripheral or tissue specific insulin resistance nor increased hepatic gluconeogenesis were present after subchronic ozone exposure. Instead, long-term ozone exposure lowered circulating insulin and severely impaired glucose-stimulated beta-cell insulin secretion. Thus, our findings in young-adult rats provide potential insights into epidemiological studies that show a positive association between ozone exposures and type 1 diabetes. Ozone-induced beta-cell dysfunction may secondarily contribute to other tissue-specific metabolic alterations following chronic exposure due to impaired regulation of glucose, lipid, and protein metabolism. - Highlights: • Subchronic episodic ozone exposure caused pulmonary and metabolic effects. • These effects were largely reversible upon one week recovery. • Ozone exposure did not cause liver or muscle insulin resistance. • Subchronic ozone exposure led to decrease in serum insulin. • Ozone severely impaired beta cell insulin secretion in response to glucose.

  13. Derangement of a factor upstream of RARalpha triggers the repression of a pleiotropic epigenetic network.

    Directory of Open Access Journals (Sweden)

    Francesca Corlazzoli

    Full Text Available Chromatin adapts and responds to extrinsic and intrinsic cues. We hypothesize that inheritable aberrant chromatin states in cancer and aging are caused by genetic/environmental factors. In previous studies we demonstrated that either genetic mutations, or loss, of retinoic acid receptor alpha (RARalpha, can impair the integration of the retinoic acid (RA signal at the chromatin of RA-responsive genes downstream of RARalpha, and can lead to aberrant repressive chromatin states marked by epigenetic modifications. In this study we tested whether the mere interference with the availability of RA signal at RARalpha, in cells with an otherwise functional RARalpha, can also induce epigenetic repression at RA-responsive genes downstream of RARalpha.To hamper the availability of RA at RARalpha in untransformed human mammary epithelial cells, we targeted the cellular RA-binding protein 2 (CRABP2, which transports RA from the cytoplasm onto the nuclear RARs. Stable ectopic expression of a CRABP2 mutant unable to enter the nucleus, as well as stable knock down of endogenous CRABP2, led to the coordinated transcriptional repression of a few RA-responsive genes downstream of RARalpha. The chromatin at these genes acquired an exacerbated repressed state, or state "of no return". This aberrant state is unresponsive to RA, and therefore differs from the physiologically repressed, yet "poised" state, which is responsive to RA. Consistent with development of homozygosis for epigenetically repressed loci, a significant proportion of cells with a defective CRABP2-mediated RA transport developed heritable phenotypes indicative of loss of function.Derangement/lack of a critical factor necessary for RARalpha function induces epigenetic repression of a RA-regulated gene network downstream of RARalpha, with major pleiotropic biological outcomes.

  14. Diagnostic studies on the internal derangement of temporomandibular joint in MR imaging (MRI)

    International Nuclear Information System (INIS)

    Tange, Kazuhisa

    1991-01-01

    The T1 and T2 relaxation times of the phantom were measured in the magnetic resonance imaging (MRI) using the headcoil and the surface coil for the temporomandibular joint (TMJ). The purpose of this study on the phantom was to investigate the feature of the surface coil for TMJ (TMJ-coil). Two spin echo (TR=2,000 msec, TE=30 msec and TR=2,000 msec, TE=80 msec) and one inversion recovery (TR=2,000 msec, TI=500 msec) pulse sequence with a 256 x 256 matrix and two excitations were used, and the T1 and T2 values were obtained by the ROI (region of interest) in the maps of T1 and T2. As a result of the phantom study, I acquired the knowledge that I have to set an object on the center of the TMJ-coil with a distance more than 3 cm. With the TMJ-coil, measurements of T1 and T2 relaxation times of meniscus and lateral pterygoid muscle were performed on 30 normal volunteers and 30 patients who had been diagnosed internal derangement of the TMJ. The 30 patients were classified into two groups; one composed of 15 patients diagnosed as meniscal displacement with reduction (group MDWR) and the other was of 15 patients diagnosed as meniscal displacement without reduction (group MDWOR). Between the volunteers and patients, there was a significant decrease in T1 and T2 relaxation times of meniscus and T1 relaxation times of lateral pterygoid muscle. There was no significant difference between group MDWR and group MDWOR. There was no significant difference in sex or age, either. The more long-term the patients were, the more the T1 relaxation times decreased. The decrease in T1 and T2 relaxation times of meniscus probably represented water loss. The decrease in T1 and T2 relaxation times of lateral pterygoid muscle was slight compared with that of meniscus. (author)

  15. Hemodynamic significance of internal carotid artery disease

    DEFF Research Database (Denmark)

    Schroeder, T

    1988-01-01

    a significant improvement in baseline flow occur. Flow reserve determined by cerebral vasodilation, however, will improve in most patients with hemodynamic failure. In addition, some patients in the low-pressure group develop marked, but temporary, hyperperfusion after reconstruction of very high grade carotid...

  16. Central Hemodynamics for Management of Arteriosclerotic Diseases.

    Science.gov (United States)

    Hashimoto, Junichiro

    2017-08-01

    Arteriosclerosis, particularly aortosclerosis, is the most critical risk factor associated with cardiovascular, cerebrovascular, and renal diseases. The pulsatile hemodynamics in the central aorta consists of blood pressure, flow, and stiffness and substantially differs from the peripheral hemodynamics in muscular arteries. Arteriosclerotic changes with age appear earlier in the elastic aorta, and age-dependent increases in central pulse pressure are more marked than those apparent from brachial pressure measurement. Central pressure can be affected by lifestyle habits, metabolic disorders, and endocrine and inflammatory diseases in a manner different from brachial pressure. Central pulse pressure widening due to aortic stiffening increases left ventricular afterload in systole and reduces coronary artery flow in diastole, predisposing aortosclerotic patients to myocardial hypertrophy and ischemia. The widened pulse pressure is also transmitted deep into low-impedance organs such as the brain and kidney, causing microvascular damage responsible for lacunar stroke and albuminuria. In addition, aortic stiffening increases aortic blood flow reversal, which can lead to retrograde embolic stroke and renal function deterioration. Central pressure has been shown to predict cardiovascular events in most previous studies and potentially serves as a surrogate marker for intervention. Quantitative and comprehensive evaluation of central hemodynamics is now available through various noninvasive pressure/flow measurement modalities. This review will focus on the clinical usefulness and mechanistic rationale of central hemodynamic measurements for cardiovascular risk management.

  17. Force plate monitoring of human hemodynamics

    Czech Academy of Sciences Publication Activity Database

    Kříž, J.; Šeba, Petr

    2008-01-01

    Roč. 2, č. 1 (2008), s. 1-9 ISSN 1753-4631 Grant - others:GA ČR(CZ) GP202/06/P130; GA MŠk(CZ) LC06002 Institutional research plan: CEZ:AV0Z10100521 Keywords : hemodynamics * balistocardiography * pulse wave velocity Subject RIV: BO - Biophysics www.nonlinearbiomedphys.com

  18. Exercise Training Prevents Cardiovascular Derangements Induced by Fructose Overload in Developing Rats.

    Directory of Open Access Journals (Sweden)

    Daniela Farah

    Full Text Available The risks of chronic diseases associated with the increasing consumption of fructose-laden foods are amplified by the lack of regular physical activity and have become a serious public health issue worldwide. Moreover, childhood eating habits are strongly related to metabolic syndrome in adults. Thus, we aimed to investigate the preventive role of exercise training undertaken concurrently with a high fructose diet on cardiac function, hemodynamics, cardiovascular autonomic modulation and oxidative stress in male rats after weaning. Male Wistar rats were divided into 4 groups (n = 8/group: Sedentary control (SC, Trained control (TC, Sedentary Fructose (SF and Trained Fructose (TF. Training was performed on a treadmill (8 weeks, 40-60% of maximum exercise test. Evaluations of cardiac function, hemodynamics, cardiovascular autonomic modulation and oxidative stress in plasma and in left ventricle (LV were performed. Chronic fructose overload induced glucose intolerance and an increase in white adipose tissue (WAT weight, in myocardial performance index (MPI (SF:0.42±0.04 vs. SC:0.24±0.05 and in arterial pressure (SF:122±3 vs. SC:113±1 mmHg associated with increased cardiac and vascular sympathetic modulation. Fructose also induced unfavorable changes in oxidative stress profile (plasmatic protein oxidation- SF:3.30±0.09 vs. SC:1.45±0.08 nmol/mg prot; and LV total antioxidant capacity (TRAP- SF: 2.5±0.5 vs. SC:12.7±1.7 uM trolox. The TF group showed reduced WAT, glucose intolerance, MPI (0.35±0.04, arterial pressure (118±2mmHg, sympathetic modulation, plasmatic protein oxidation and increased TRAP when compared to SF group. Therefore, our findings indicate that cardiometabolic dysfunctions induced by fructose overload early in life may be prevented by moderate aerobic exercise training.

  19. Exercise Training Prevents Cardiovascular Derangements Induced by Fructose Overload in Developing Rats

    Science.gov (United States)

    Farah, Daniela; Nunes, Jonas; Sartori, Michelle; Dias, Danielle da Silva; Sirvente, Raquel; Silva, Maikon B.; Fiorino, Patrícia; Morris, Mariana; Llesuy, Susana; Farah, Vera; Irigoyen, Maria-Cláudia; De Angelis, Kátia

    2016-01-01

    The risks of chronic diseases associated with the increasing consumption of fructose-laden foods are amplified by the lack of regular physical activity and have become a serious public health issue worldwide. Moreover, childhood eating habits are strongly related to metabolic syndrome in adults. Thus, we aimed to investigate the preventive role of exercise training undertaken concurrently with a high fructose diet on cardiac function, hemodynamics, cardiovascular autonomic modulation and oxidative stress in male rats after weaning. Male Wistar rats were divided into 4 groups (n = 8/group): Sedentary control (SC), Trained control (TC), Sedentary Fructose (SF) and Trained Fructose (TF). Training was performed on a treadmill (8 weeks, 40–60% of maximum exercise test). Evaluations of cardiac function, hemodynamics, cardiovascular autonomic modulation and oxidative stress in plasma and in left ventricle (LV) were performed. Chronic fructose overload induced glucose intolerance and an increase in white adipose tissue (WAT) weight, in myocardial performance index (MPI) (SF:0.42±0.04 vs. SC:0.24±0.05) and in arterial pressure (SF:122±3 vs. SC:113±1 mmHg) associated with increased cardiac and vascular sympathetic modulation. Fructose also induced unfavorable changes in oxidative stress profile (plasmatic protein oxidation- SF:3.30±0.09 vs. SC:1.45±0.08 nmol/mg prot; and LV total antioxidant capacity (TRAP)- SF: 2.5±0.5 vs. SC:12.7±1.7 uM trolox). The TF group showed reduced WAT, glucose intolerance, MPI (0.35±0.04), arterial pressure (118±2mmHg), sympathetic modulation, plasmatic protein oxidation and increased TRAP when compared to SF group. Therefore, our findings indicate that cardiometabolic dysfunctions induced by fructose overload early in life may be prevented by moderate aerobic exercise training. PMID:27930685

  20. Noninvasive Hemodynamic Assessment as Part of Preoperative Examination of Patients with Colorectal Cancer

    Directory of Open Access Journals (Sweden)

    M. I. Aleksandrov

    2014-01-01

    Full Text Available Objective: to determine the capacities of a noninvasive hemodynamic study in patients with colorectal cancer within a preoperative anesthesiological examination. Subjects and methods. The hemodynamic status was preoperatively analyzed in 97 patients (46 men and 51 women with colorectal cancer. Their mean age was 67.59±9.48 years. The POSSUM intraoperative risk scores were 20.20+3.2. Central hemodynamics was preoperatively assessed in all the patients, by applying a «Computerized Diamant System for Monitoring the Cardiorespiratory System and Tissue Hydration» (Saint-Petersburg, Russia — Registration Certificate ФСР No 2008/03201 dated 22 August, 2008.Results. The non-invasive hemodynamic study can supplement a preoperative examination in patients with colorectal cancer. The patients with colorectal cancer were diagnosed as having hypodynamic and eudynamic circulation in 43.3 and 56.7% of the cases, respectively. The age of the patients was not established to have a significant impact on their hemodynamic status, which confirms that it is expedient to make perioperative multifactorial risk assessment.

  1. Determinant Factors for Arterial Hemodynamics in Hypertension: Theoretical Insights From a Computational Model-Based Study.

    Science.gov (United States)

    Liang, Fuyou; Guan, Debao; Alastruey, Jordi

    2018-03-01

    Hypertension is a well-documented predictive factor for cardiovascular events. Clinical studies have extensively demonstrated the differential hemodynamic consequences of various antihypertensive drugs, but failed to clearly elucidate the underlying mechanisms due to the difficulty in performing a quantitative deterministic analysis based on clinical data that carry confounding information stemming from interpatient differences and the nonlinearity of cardiovascular hemodynamics. In the present study, a multiscale model of the cardiovascular system was developed to quantitatively investigate the relationships between hemodynamic variables and cardiovascular properties under hypertensive conditions, aiming to establish a theoretical basis for assisting in the interpretation of clinical observations or optimization of therapy. Results demonstrated that heart period, central arterial stiffness, and arteriolar radius were the major determinant factors for blood pressures and flow pulsatility indices both in large arteries and in the microcirculation. These factors differed in the degree and the way in which they affect hemodynamic variables due to their differential effects on wave reflections in the vascular system. In particular, it was found that the hemodynamic effects of varying arteriolar radius were considerably influenced by the state of central arterial stiffness, and vice versa, which implied the potential of optimizing antihypertensive treatment by selecting proper drugs based on patient-specific cardiovascular conditions. When analyzed in relation to clinical observations, the simulated results provided mechanistic explanations for the beneficial pressure-lowering effects of vasodilators as compared to β-blockers, and highlighted the significance of monitoring and normalizing arterial stiffness in the treatment of hypertension.

  2. A sliding mode observer for hemodynamic characterization under modeling uncertainties

    KAUST Repository

    Zayane, Chadia

    2014-06-01

    This paper addresses the case of physiological states reconstruction in a small region of the brain under modeling uncertainties. The misunderstood coupling between the cerebral blood volume and the oxygen extraction fraction has lead to a partial knowledge of the so-called balloon model describing the hemodynamic behavior of the brain. To overcome this difficulty, a High Order Sliding Mode observer is applied to the balloon system, where the unknown coupling is considered as an internal perturbation. The effectiveness of the proposed method is illustrated through a set of synthetic data that mimic fMRI experiments.

  3. Cerebral hemodynamic and metabolic changes in fulminant hepatic failure

    Directory of Open Access Journals (Sweden)

    Fernando Mendes Paschoal Junior

    Full Text Available ABSTRACT Intracranial hypertension and brain swelling are a major cause of morbidity and mortality of patients suffering from fulminant hepatic failure (FHF. The pathogenesis of these complications has been investigated in man, in experimental models and in isolated cell systems. Currently, the mechanism underlying cerebral edema and intracranial hypertension in the presence of FHF is multi-factorial in etiology and only partially understood. The aim of this paper is to review the pathophysiology of cerebral hemodynamic and metabolism changes in FHF in order to improve understanding of intracranial dynamics complication in FHF.

  4. Hemodynamic changes after levothyroxine treatment in subclinical hypothyroidism

    DEFF Research Database (Denmark)

    Faber, J; Petersen, L; Wiinberg, N

    2002-01-01

    In hypothyroidism, lack of thyroid hormones results in reduced cardiac function (cardiac output [CO]), and an increase of systemic vascular resistance (SVR). We speculated whether hemodynamic regulation in subjects with subclinical hypothyroidism (SH) (defined as mildly elevated thyrotropin [TSH.......05). These changes were qualitatively similar but quantitatively less pronounced than in 15 women with overt hypothyroidism, also studied. Taking the two groups together (n = 31), pretreatment thyroid function (expressed as either TSH or free T(4) estimate) correlated to CO and SVR as well as the changes induced...... by LT(4) (p hypothyroidism should...

  5. Intraoperative hemodynamic monitoring during liver transplantation: goals and devices

    DEFF Research Database (Denmark)

    Nissen, Peter; Frederiksen, H J; Secher, N H

    2010-01-01

    With the introduction of orthotopic liver transplantation (OLT) almost 40 years ago, changes in the cardiovascular system that manifest during the different phases of the operation combined, sometimes with massive hemorrhage in likely critically ill patients have been a challenge. Here hemodynamic...... for other categories of patients when a flow related parameter (cardiac stroke volume, cardiac output or (mixed) venous oxygen saturation) does not respond to a fluid challenge, i.e. the patient is "normovolaemic". Also the administration strategy for liver transplantation is considered with emphasis...

  6. Effects of tilting on central hemodynamics and homeostatic mechanisms in cirrhosis

    DEFF Research Database (Denmark)

    Møller, Søren; Nørgaard, Annette; Henriksen, Jens H

    2004-01-01

    Patients with cirrhosis have a hyperdynamic circulation and an abnormal blood volume distribution with central hypovolemia, an activated sympathetic nervous system (SNS) as well as the renin-angiotensin-aldosterone system (RAAS). As the hyperdynamic circulation in cirrhosis may be present only in...... the CBV less in patients with cirrhosis, and the results suggest a differential regulation of central hemodynamics in patients with cirrhosis....

  7. Derangements of lacrimal drainage-associated lymphoid tissue (LDALT) in human chronic dacryocystitis.

    Science.gov (United States)

    Ali, Mohammad Javed; Mulay, Kaustubh; Pujari, Aditi; Naik, Milind N

    2013-12-01

    epithelium (54.5%, 109/200), and stromal fibrosis (88%, 176/200). This study presents the largest series to date (n = 200 lacrimal sacs) exclusively on changes in lacrimal drainage-associated lymphoid tissue in human chronic dacryocystitis. This study could be the starting point for further exploration into the molecular biology, immunological implications, and possible implications of LDALT derangements on etiopathogenesis of primary acquired nasolacrimal duct obstruction.

  8. A review of hemodynamic monitoring techniques, methods and devices for the emergency physician.

    Science.gov (United States)

    Laher, Abdullah E; Watermeyer, Matthew J; Buchanan, Sean K; Dippenaar, Nicole; Simo, Nelly Clotilde Tchouambou; Motara, Feroza; Moolla, Muhammed

    2017-09-01

    The emergency department (ED) is frequently the doorway to the intensive care unit (ICU) for a significant number of critically ill patients presenting to the hospital. Hemodynamic monitoring (HDM) which is a key component in the effective management of the critically ill patient presenting to the ED, is primarily concerned with assessing the performance of the cardiovascular system and determining the correct therapeutic intervention to optimise end-organ oxygen delivery. The spectrum of hemodynamic monitoring ranges from simple clinical assessment and routine bedside monitoring to point of care ultrasonography and various invasive monitoring devices. The clinician must be aware of the range of available techniques, methods, interventions and technological advances as well as possess a sound approach to basic hemodynamic monitoring prior to selecting the optimal modality. This article comprises an in depth discussion of an approach to hemodynamic monitoring techniques and principles as well as methods of predicting fluid responsiveness as it applies to the ED clinician. We review the role, applicability and validity of various methods and techniques that include; clinical assessment, passive leg raising, blood pressure, finger based monitoring devices, the mini-fluid challenge, the end-expiratory occlusion test, central venous pressure monitoring, the pulmonary artery catheter, ultrasonography, bioreactance and other modern invasive hemodynamic monitoring devices. Copyright © 2017 Elsevier Inc. All rights reserved.

  9. Hemodynamic and lactic Acid responses to proprioceptive neuromuscular facilitation exercise.

    Science.gov (United States)

    Gültekin, Zuhal; Kin-Isler, Ayse; Sürenkök, Ozgür

    2006-01-01

    The hemodynamic and metabolic responses to proprioceptive neuromuscular facilitation (PNF) exercise were examined in 32 male university students (aged 19-28 years). Ten repetitions of PNF exercises were applied to the subjects' dominant upper extremities in the following order: as an agonist pattern flexion, adduction and external rotation; and as an antagonist pattern extension, abduction and internal rotation. Heart rate (HR), systolic blood pressure (SBP), diastolic blood pressure (DBP), double product (DP), and blood lactate concentration (La) were determined before, immediately after, and at 1(st), 3(rd), and 5(th) minutes after PNF exercise. A one-way ANOVA with repeated measures indicated significant differences in HR, SBP, DBP, DP and La immediately after PNF exercise. HR increased from 81 (±10) to 108 (±15) b·min(-1) (p < 0.01), SBP increased from 117 (±10) to 125 (±11) mmHg (p < 0.01), DBP increased from 71 (±10) to 75 (±8) mmHg (p < 0.01), DP increased from 96 (±16) to 135 (±24) (p < 0.01), and La increased from 0.69 (±0.31) to 3.99 (±14.63) mmol·L(-1) (p < 0.01). Thus PNF exercise resulted in increased hemodynamic responses and blood lactate concentration that indicate a high strain on the cardiovascular system and anaerobic metabolism in healthy subjects. Key PointsPNF exercises resulted in increased hemodynamic responses.Repeated PNF exercises resulted in an increased blood lactate concentration.

  10. Post-Treatment Hemodynamics of a Basilar Aneurysm and Bifurcation

    Energy Technology Data Exchange (ETDEWEB)

    Ortega, J; Hartman, J; Rodriguez, J; Maitland, D

    2008-01-16

    Aneurysm re-growth and rupture can sometimes unexpectedly occur following treatment procedures that were initially considered to be successful at the time of treatment and post-operative angiography. In some cases, this can be attributed to surgical clip slippage or endovascular coil compaction. However, there are other cases in which the treatment devices function properly. In these instances, the subsequent complications are due to other factors, perhaps one of which is the post-treatment hemodynamic stress. To investigate whether or not a treatment procedure can subject the parent artery to harmful hemodynamic stresses, computational fluid dynamics simulations are performed on a patient-specific basilar aneurysm and bifurcation before and after a virtual endovascular treatment. The simulations demonstrate that the treatment procedure produces a substantial increase in the wall shear stress. Analysis of the post-treatment flow field indicates that the increase in wall shear stress is due to the impingement of the basilar artery flow upon the aneurysm filling material and to the close proximity of a vortex tube to the artery wall. Calculation of the time-averaged wall shear stress shows that there is a region of the artery exposed to a level of wall shear stress that can cause severe damage to endothelial cells. The results of this study demonstrate that it is possible for a treatment procedure, which successfully excludes the aneurysm from the vascular system and leaves no aneurysm neck remnant, to elevate the hemodynamic stresses to levels that are injurious to the immediately adjacent vessel wall.

  11. Preeclampsia: A review of the pathogenesis and possible management strategies based on its pathophysiological derangements.

    Science.gov (United States)

    El-Sayed, Amel A F

    2017-10-01

    This review is divided into three parts. The first part briefly describes the pathogenesis of preeclampsia. This is followed by reviewing previously reported management strategies of the disease based on its pathophysiological derangements. Finally, the author defines the safe and acceptable methods/medications that may be used to 'prevent' preeclampsia (in high risk patients) and those that may be used to 'treat' preeclampsia (meant to prolong the pregnancy in patients with established preeclampsia). The review concludes that multi-center trials are required to include multiple drugs in the same management protocol. Copyright © 2017. Published by Elsevier B.V.

  12. Preeclampsia: A review of the pathogenesis and possible management strategies based on its pathophysiological derangements

    Directory of Open Access Journals (Sweden)

    Amel A.F. El-Sayed

    2017-10-01

    Full Text Available This review is divided into three parts. The first part briefly describes the pathogenesis of preeclampsia. This is followed by reviewing previously reported management strategies of the disease based on its pathophysiological derangements. Finally, the author defines the safe and acceptable methods/medications that may be used to ‘prevent’ preeclampsia (in high risk patients and those that may be used to ‘treat’ preeclampsia (meant to prolong the pregnancy in patients with established preeclampsia. The review concludes that multi-center trials are required to include multiple drugs in the same management protocol.

  13. Improvement in Hemodynamics After Methylene Blue Administration in Drug-Induced Vasodilatory Shock: A Case Report.

    Science.gov (United States)

    Laes, JoAn R; Williams, David M; Cole, Jon B

    2015-12-01

    The purpose of this study is to describe a case where methylene blue improved hemodynamics in a poisoned patient. This is a single case report where a poisoned patient developed vasodilatory shock following ingestion of atenolol, amlodipine, and valsartan. Shock persisted after multiple therapies including vasopressors, high-dose insulin, hemodialysis, and 20% intravenous fat emulsion. Methylene blue (2 mg/kg IV over 30 min) was administered in the ICU with temporal improvement as measured by pulmonary artery catheter hemodynamic data pre- and post-methylene blue administration. Within 1 h of methylene blue administration, systemic vascular resistance improved (240 dyn s/cm5 increased to 1204 dyn s/cm5), and vasopressor requirements decreased with maintenance of mean arterial pressure 60 mmHg. Methylene blue may improve hemodynamics in drug-induced vasodilatory shock and should be considered in critically ill patients poisoned with vasodilatory medications refractory to standard therapies.

  14. Estimated venous return surface and cardiac output curve precisely predicts new hemodynamics after volume change.

    Science.gov (United States)

    Sugimachi, Masaru; Sunagawa, Kenji; Uemura, Kazunori; Kamiya, Atsunori; Shimizu, Shuji; Inagaki, Masashi; Shishido, Toshiaki

    2010-01-01

    In our extended Guyton's model, the ability of heart to pump blood is characterized by a cardiac output curve and the ability of vasculature to pool blood by a venous return surface. These intersect in a three-dimensional coordinate system at the operating right atrial pressure, left atrial pressure, and cardiac output. The baseline cardiac output curve and venous return surface and their changes after volume change would predict new hemodynamics. The invasive methods needed to precisely characterize cardiac output curve and venous return surface led us to aim at estimating cardiac output curve and venous return surface from a single hemodynamic measurement. Using the average values for two logarithmic function parameters, and for two slopes of a surface, we were able to estimate cardiac output curve and venous return surface. The estimated curve and surface predicted new hemodynamics after volume change precisely.

  15. Cardiovascular and hemodynamic responses to adapted physical exercises in very old adults.

    Science.gov (United States)

    Panzarino, Michele; Gravina, Angela; Carosi, Veronica; Crobeddu, Patrizio; Tiroli, Alessia; Lombardi, Roberto; D'Ottavio, Stefano; Galante, Alberto; Legramante, Jacopo M

    2017-06-01

    Aging is characterized by a physiological reduction in physical activity, which is inversely correlated with survival. Aim of the present study is to evaluate the cardiovascular, central hemodynamic and autonomic responses to a single bout of adapted physical exercise in octogenarian subjects. We studied cardiovascular, hemodynamic and autonomic responses to adapted physical activity in 33 subjects by a noninvasive methodology (Nexfin ® , Edwards Lifesciences Corporation). Our octogenarians presented a significant increase in mean arterial pressure (p cardiovascular system and to induce a postexercise hypotension similarly to adults. The baroreflex control of sinus node seems to contribute in the physiological mechanism of these cardiovascular adaptations. In very old people, physical activity induces cardiovascular and hemodynamic responses not significantly different from those induced in adult even though some cautions particularly in the early recovery phase after exercise should be exercised.

  16. Biology and hemodynamics of aneurismal vasculopathies

    International Nuclear Information System (INIS)

    Pereira, Vitor Mendes; Brina, Olivier; Gonzalez, Ana Marcos; Narata, Ana Paula; Ouared, Rafik; Karl-Olof, Lovblad

    2013-01-01

    Aneurysm vasculopathies represents a group of vascular disorders that share a common morphological diagnosis: a vascular dilation, the aneurysm. They can have a same etiology and a different clinical presentation or morphology, or have different etiology and very similar anatomical geometry. The biology of the aneurysm formation is a complex process that will be a result of an endogenous predisposition and epigenetic factors later on including the intracranial hemodynamics. We describe the biology of saccular aneurysms, its growth and rupture, as well as, current concepts of hemodynamics derived from application of computational flow dynamics on patient specific vascular models. Furthermore, we describe different aneurysm phenotypes and its extremely variability on morphological and etiological presentation

  17. Hemodynamic significance of internal carotid artery disease

    DEFF Research Database (Denmark)

    Schroeder, T

    1988-01-01

    Neurologic symptoms in the region of an internal carotid artery stenosis are considered to be embolic in most instances. Only in a subgroup has carotid occlusive disease with impairment of the collateral supply, caused a state of hemodynamic failure with marked reduction of perfusion pressure....... Though unproven, it is reasonable to assume that without surgical intervention, the risk is higher than average for patients with hemodynamic failure. Equally, should there be any postoperative improvement of cerebral blood flow or neurologic deficits, it should be looked for in this group. Thus......, it is necessary to distinguish those with low perfusion pressure from the population of patients with carotid artery disease. Preoperative clinical evaluation and direct visualization of the carotid bifurcation should be supplemented by indirect physiological tests which allow assessment of collateral perfusion...

  18. Hemodynamic function of the standard St. Jude bileaflet disc valve has no clinical impact 10 years after aortic valve replacement

    DEFF Research Database (Denmark)

    Lund, Ole; Dorup, Inge; Emmertsen, Kristian

    2005-01-01

    OBJECTIVES: Size mismatch and impaired left ventricular function have been shown to determine the hemodynamic function of the standard St. Jude bileaflet disc valve early after aortic valve replacement (AVR). We aimed to analyse St. Jude valve hemodynamic function and its clinical impact in the s......OBJECTIVES: Size mismatch and impaired left ventricular function have been shown to determine the hemodynamic function of the standard St. Jude bileaflet disc valve early after aortic valve replacement (AVR). We aimed to analyse St. Jude valve hemodynamic function and its clinical impact......Hg. In a multilinear regression analysis GOA indexed for LVEDD, hypertension, and LVEF were independently related to peak gradient. CONCLUSION: High gradients of the standard St. Jude bileaflet disc valve 10 years after AVR was primarily related to systemic hypertension and mismatch between valve and left ventricular...

  19. HEMODYNAMIC EFFECTS OF XENON ANESTHESIA IN CHILDREN

    Directory of Open Access Journals (Sweden)

    M. V. Bykov

    2014-01-01

    Full Text Available The study was aimed at hemodynamic effects of xenon on operative interventions in children. Patients and methods: the study involved 30 5-17-year-old children – 10 (33.3% girls and 20 (66.7% boys with ASA score 1-3 admitted for surgical treatment. The children underwent endotracheal anesthesia with xenon-oxygen mixture (Xe:O2 = 60-65:30% and fentanyl (2.5‑3.5  mcg/kg per hour for the following operations: appendectomy – 10 (33.3% patients, herniotomy – 8 (26.7% patients, Ivanissevich procedure – 6 (20.0% patients, plastic surgery of posttraumatic defects of skin and soft tissues – 4 (13.3% patients, abdominal adhesiotomy – 2 (6.7% patients. Central hemodynamics was studied echocardiographically (Philips HD 11, the Netherlands using the Teichholz technique along the cephalocaudal axis (parasternal access. Results: the anesthesia was notable for hemodynamic stability during the operation: as a result, a statistically significant (p < 0.05 increase in systolic, diastolic and mean arterial pressure by 10, 18 and 17%, respectively, was observed. Conclusion: the analysis demonstrated that xenon anesthesia improves lusitropic myocardial function statistically significantly increasing cardiac output by 12% by way of increasing stroke volume by 30%. 

  20. Efficacy of Arthrocentesis with Injection of Hyaluronic Acid in the Treatment of Internal Derangement of Temporomandibular Joint

    Directory of Open Access Journals (Sweden)

    Pramila Shakya

    2010-07-01

    Full Text Available This cross-sectional study was designed to find out the effect of arthrocentesis with injection hyaluronic acid in thetreatment of internal derangement of temporomandibular joint (TMJ ID for the restoration of TMJ function. The studyincluded 25 patients, aged 13 to 50 years with symptoms of TMJ pain and clicking during function and limited mouthopening. TMJ ID was assessed with clinical examination and conformed with MRI. Arthrocentesis was done withinsertion of two 21gauze needles in the upper joint compartment and joint lavaged with 200 ml of ringer’s lactate solutionand at the end 1ml of hyaluronic acid was injected. Intensity of TMJ pain and clicking was assessed using visual analogscale, maximum mouth opening, lateral jaw movement and protrusion were assessed with millimeter scale. All theparameters were measured before the procedure , immediately after the procedure then after 2 weeks, 1 month , 3 monthsand 6 months procedure. During 6 months follow-up, clinical examination and comparison of the results showed 84%reduction in TMJ pain, 92% improvement in mouth opening and clicking disappear in 80% of patients.Key words: TMJ pain; clicking; internal derangement; arthrocentesis; hyaluronic acid.DOI: 10.3329/bsmmuj.v3i1.5509BSMMU J 2010; 3(1: 18-22

  1. Successful renal transplantation from a brain-dead deceased donor with head injury, disseminated intravascular coagulation and deranged renal functions

    Directory of Open Access Journals (Sweden)

    P P Ghuge

    2013-01-01

    Full Text Available Deceased donors (DDs with the brain death due to head injury are the major source of organs for transplantation. The incidence of post-head injury disseminated intravascular coagulation (DIC ranges from 24% to 50%. Many centers do not accept organs from donors with DIC due to increased risk of primary graft non-function and/or high chances of morbidity/mortality. We performed two successful renal transplants from a DD with head injury with DIC and deranged renal function. One of the recipients developed transient thrombocytopenia, but there was no evidence of DIC or delayed graft functions in either of the recipients. Over a follow-up of 1 month, both are doing well with stable graft function and hematological profile. Thus, a carefully selected DD with severe DIC even with deranged renal function is not a contraindication for organ donation if other risk factors for primary non-function are excluded. This approach will also help in overcoming organ shortage.

  2. Novel Regulators of Hemodynamics in the Pregnant Uterus.

    Science.gov (United States)

    Clark, N C; Pru, C A; Pru, J K

    2017-01-01

    The uterus is a highly dynamic organ, undergoing dramatic physiological changes during normal cyclicity and pregnancy. Many of these changes involve remodeling of the uterine vasculature in order to provide oxygen and nutrients to the developing embryo/fetus. Vasculogenesis, angiogenesis, vasodilation/vasoconstriction, and vascular permeability are coordinated by a vast network of autocrine, paracrine, and endocrine-signaling factors that derive from a number of cellular sources at the maternal:fetal interface, as well as from tissue outside the uterus. In this chapter, the dynamic changes that occur in uterine vasculature during pregnancy are described, and some of the hemodynamic regulatory factors are reviewed. These include uterine natural killer cells, sex steroid hormones, the calcitonin gene-related peptide family, angiopoietins, sphingolipids, and the renin-angiotensin system. Aberrancies in these factors are associated with disorders of uterine vascular remodeling, leading to conditions such as early pregnancy loss, preeclampsia, uterine hemorrhage, and intrauterine growth restriction. In addition, we introduce the role of the mas-related gene family in angiotensin signaling and endothelial function during pregnancy. Finally, this chapter introduces the novel concept that in addition to remodeling the vasculature to bring oxygenated maternal blood to the embryo, the gravid uterus synthesizes its own hemoglobin. Overall, this chapter provides an overview of the regulators of uterine vascular remodeling and hemodynamics during pregnancy and pregnancy-associated pathologies. © 2017 Elsevier Inc. All rights reserved.

  3. HEMODYNAMIC AND LACTIC ACID RESPONSES TO PROPRIOCEPTIVE NEUROMUSCULAR FACILITATION EXERCISE

    Directory of Open Access Journals (Sweden)

    Zuhal Gültekin

    2006-09-01

    Full Text Available The hemodynamic and metabolic responses to proprioceptive neuromuscular facilitation (PNF exercise were examined in 32 male university students (aged 19-28 years. Ten repetitions of PNF exercises were applied to the subjects' dominant upper extremities in the following order: as an agonist pattern flexion, adduction and external rotation; and as an antagonist pattern extension, abduction and internal rotation. Heart rate (HR, systolic blood pressure (SBP, diastolic blood pressure (DBP, double product (DP, and blood lactate concentration (La were determined before, immediately after, and at 1st, 3rd, and 5th minutes after PNF exercise. A one-way ANOVA with repeated measures indicated significant differences in HR, SBP, DBP, DP and La immediately after PNF exercise. HR increased from 81 (±10 to 108 (±15 b·min-1 (p < 0.01, SBP increased from 117 (±10 to 125 (±11 mmHg (p < 0.01, DBP increased from 71 (±10 to 75 (±8 mmHg (p < 0.01, DP increased from 96 (±16 to 135 (±24 (p < 0.01, and La increased from 0.69 (±0.31 to 3.99 (±14.63 mmol·L-1 (p < 0.01. Thus PNF exercise resulted in increased hemodynamic responses and blood lactate concentration that indicate a high strain on the cardiovascular system and anaerobic metabolism in healthy subjects

  4. Hemodynamic simulations in coronary aneurysms of children with Kawasaki disease

    Science.gov (United States)

    Sengupta, Dibyendu; Burns, Jane; Marsden, Alison

    2009-11-01

    Kawasaki disease (KD) is a serious pediatric illness affecting the cardiovascular system. One of the most serious complications of KD, occurring in about 25% of untreated cases, is the formation of large aneurysms in the coronary arteries, which put patients at risk for myocardial infarction. In this project we performed patient specific computational simulations of blood flow in aneurysmal left and right coronary arteries of a KD patient to gain an understanding about their hemodynamics. Models were constructed from CT data using custom software. Typical pulsatile flow waveforms were applied at the model inlets, while resistance and RCR lumped models were applied and compared at the outlets. Simulated pressure waveforms compared well with typical physiologic data. High wall shear stress values are found in the narrow region at the base of the aneurysm and low shear values occur in regions of recirculation. A Lagrangian approach has been adopted to perform particle tracking and compute particle residence time in the recirculation. Our long-term goal will be to develop links between hemodynamics and the risk for thrombus formation in order to assist in clinical decision-making.

  5. Patient-Specific Modeling of Interventricular Hemodynamics in Single Ventricle Physiology

    Science.gov (United States)

    Vedula, Vijay; Feinstein, Jeffrey; Marsden, Alison

    2016-11-01

    Single ventricle (SV) congenital heart defects, in which babies are born with only functional ventricle, lead to significant morbidity and mortality with over 30% of patients developing heart failure prior to adulthood. Newborns with SV physiology typically undergo three palliative surgeries, in which the SV becomes the systemic pumping chamber. Depending on which ventricle performs the systemic function, patients are classified as having either a single left ventricle (SLV) or a single right ventricle (SRV), with SRV patients at higher risk of failure. As the native right ventricles are not designed to meet systemic demands, they undergo remodeling leading to abnormal hemodynamics. The hemodynamic characteristics of SLVs compared with SRVs is not well established. We present a validated computational framework for performing patient-specific modeling of ventricular flows, and apply it across 6 SV patients (3SLV + 3SRV), comparing hemodynamic conditions between the two subgroups. Simulations are performed with a stabilized finite element method coupled with an immersed boundary method for modeling heart valves. We discuss identification of hemodynamic biomarkers of ventricular remodeling for early risk assessment of failure. This research is supported in part by the Stanford Child Health Research Institute and the Stanford NIH-NCATS-CTSA through Grant UL1 TR001085 and due to U.S. National Institute of Health through NIH NHLBI R01 Grants 5R01HL129727-02 and 5R01HL121754-03.

  6. Occupational exposure in hemodynamic; Exposicao ocupacional em hemodinamica

    Energy Technology Data Exchange (ETDEWEB)

    Silva, Amanda J.; Fernandes, Ivani M.; Silva, Paula P. Nou; Sordi, Gian Maria A.A.; Carneiro, Janete C.G.G., E-mail: ajsilva@ipen.b, E-mail: imfernandes@ipen.b, E-mail: ppsilva@ipen.b, E-mail: gmsordi@ipen.b, E-mail: janetegc@ipen.b [Instituto de Pesquisas Energeticas e Nucleares (IPEN/CNEN-SP), Sao Paulo, SP (Brazil)

    2011-10-26

    This paper has an objective to perform a radiometric survey at a hemodynamic service. Besides, it was intended to evaluate the effective dose of health professionals and to provide data which can contribute with minimization of exposures during the realization of hemodynamic procedure. The radiometric survey was realized in the real environment of work simulating the conditions of a hemodynamic study with a ionization chamber

  7. Hemodynamic Effect of Laser Therapy in Spontaneously Hypertensive Rats

    Directory of Open Access Journals (Sweden)

    Suely Tomimura

    2014-08-01

    Full Text Available Systemic arterial hypertension (SAH is considered to be the greatest risk factor for the development of neuro-cardiovascular pathologies, thus constituting a severe Public Health issue in the world. The Low-Level Laser Therapy (LLLT, or laser therapy, activates components of the cellular structure, therefore converting luminous energy into photochemical energy and leading to biophysical and biochemical reactions in the mitochondrial respiratory chain. The LLLT promotes cellular and tissue photobiomodulation by means of changes in metabolism, leading to molecular, cellular and systemic changes. The objective of this study was to analyze the action of low-level laser in the hemodynamic modulation of spontaneously hypertensive rats, in the long term. Animals (n = 16 were randomly divided into the Laser Group (n = 8, which received three weekly LLLT irradiations for seven weeks, and into the Sham Group (n = 8, which received three weekly simulations of laser for seven weeks, accounting for 21 applications in each group. After seven weeks, animals were cannulated by the implantation of a catheter in the left carotid artery. On the following day, the systemic arterial pressure was recorded. The Laser Group showed reduced levels of mean blood pressure, with statistically significant reduction (169 ± 4 mmHg* vs. 182 ± 4 mmHg from the Sham Group and reduced levels of diastolic pressure (143 ± 4 mmHg* vs. 157 ± 3 mmHg from the Sham Group, revealing a 13 and 14 mmHg decrease, respectively. Besides, there was a concomitant important decline in heart rate (312 ± 14 bpm vs. 361 ± 13 bpm from the Sham Group. Therefore, laser therapy was able to produce hemodynamic changes, thus reducing pressure levels in spontaneously hypertensive rats.

  8. Hemodynamic Effect of Laser Therapy in Spontaneously Hypertensive Rats

    Energy Technology Data Exchange (ETDEWEB)

    Tomimura, Suely, E-mail: suelytomimura@uol.com.br [Programa de Pós-Graduação em Biofotônica em Ciências da Saúde da Universidade Nove de Julho (UNINOVE) (Brazil); Silva, Bianca Passos Assumpção [Programa de Graduação e Pós-Graduação em Medicina da UNINOVE (Brazil); Sanches, Iris Callado [Laboratório de Fisiologia Translacional da UNINOVE (Brazil); Canal, Marina [Programa de Graduação e Pós-Graduação em Medicina da UNINOVE (Brazil); Consolim-Colombo, Fernanda [Programa de Graduação e Pós-Graduação em Medicina da UNINOVE (Brazil); Unidade de Hipertensão e Central Médica de Laser do Instituto do Coração - Hospital das Clinicas da Faculdade de Medicina da Universidade de São Paulo (InCor/HC-FMUSP), São Paulo, SP (Brazil); Conti, Felipe Fernandes; Angelis, Katia De [Laboratório de Fisiologia Translacional da UNINOVE (Brazil); Chavantes, Maria Cristina [Programa de Pós-Graduação em Biofotônica em Ciências da Saúde da Universidade Nove de Julho (UNINOVE) (Brazil); Programa de Graduação e Pós-Graduação em Medicina da UNINOVE (Brazil); Unidade de Hipertensão e Central Médica de Laser do Instituto do Coração - Hospital das Clinicas da Faculdade de Medicina da Universidade de São Paulo (InCor/HC-FMUSP), São Paulo, SP (Brazil)

    2014-08-15

    Systemic arterial hypertension (SAH) is considered to be the greatest risk factor for the development of neuro-cardiovascular pathologies, thus constituting a severe Public Health issue in the world. The Low-Level Laser Therapy (LLLT), or laser therapy, activates components of the cellular structure, therefore converting luminous energy into photochemical energy and leading to biophysical and biochemical reactions in the mitochondrial respiratory chain. The LLLT promotes cellular and tissue photobiomodulation by means of changes in metabolism, leading to molecular, cellular and systemic changes. The objective of this study was to analyze the action of low-level laser in the hemodynamic modulation of spontaneously hypertensive rats, in the long term. Animals (n = 16) were randomly divided into the Laser Group (n = 8), which received three weekly LLLT irradiations for seven weeks, and into the Sham Group (n = 8), which received three weekly simulations of laser for seven weeks, accounting for 21 applications in each group. After seven weeks, animals were cannulated by the implantation of a catheter in the left carotid artery. On the following day, the systemic arterial pressure was recorded. The Laser Group showed reduced levels of mean blood pressure, with statistically significant reduction (169 ± 4 mmHg* vs. 182 ± 4 mmHg from the Sham Group) and reduced levels of diastolic pressure (143 ± 4 mmHg* vs. 157 ± 3 mmHg from the Sham Group), revealing a 13 and 14 mmHg decrease, respectively. Besides, there was a concomitant important decline in heart rate (312 ± 14 bpm vs. 361 ± 13 bpm from the Sham Group). Therefore, laser therapy was able to produce hemodynamic changes, thus reducing pressure levels in spontaneously hypertensive rats.

  9. [Synopsis of endocrine and hemodynamic changes in heart failure].

    Science.gov (United States)

    Wedler, B

    1991-01-01

    In contradiction earlier viewpoints, cardiac failure cannot be defined as a purely hemodynamic problem nor as only a cardiac problem. On the other hand decreased cardiac output (Co), increased filling pressure, increased wallstress and myocardial O2-consumption (MVO2) are the cause of many humoral counterregulations. Therefore, it is not always certain if the observed alterations are the causes or consequences of cardiac failure. The systemic counter-regulations will be modulated by desensitized cardiopulmonary mechanoreceptors, followed by decreased inhibition of central vasomotoric stimuli and endothelial and endocardial function, by altered signal transmission, as well as by altered gene expression within the myocytes. Depending on the degree of insufficiency, it may be attempted, by increase of the preload and of the contractility, to restore the hemodynamic basic situation. Such an attempt is based upon increased activity of the sympathetic nervous system, stimulation of the renin-angiotensin-aldosterone-system (RAAS) or the increased level of ADH. The reduced contractility and response of the myocytes, caused by the downregulation of beta 1-receptors and Gs-proteins, as well as by the upregulation of Gi-proteins, and the increased afterload with increased MVO2 and decreased CO all lead to a vicious circle. There are only some mechanisms that are directed against these regulations. The decreased response of the myocardium to endogenous catecholamines, the stimulation of ANP-secretion, as well of the prostaglandin-secretion are among the favorable regulations. They cause increase of natri- and diuresis, improved renal perfusion, vasodilatation, and inhibition of the RAAS and ADH-secretion with reduction of true thirst and craving for salt.(ABSTRACT TRUNCATED AT 250 WORDS)

  10. A Derangement of the Brain Wound Healing Process May Cause Some Cases of Alzheimer’s Disease

    Science.gov (United States)

    Lehrer, Steven; Rheinstein, Peter H.

    2016-01-01

    A derangement of brain wound healing may cause some cases of Alzheimer’s disease. Wound healing, a highly complex process, has four stages: hemostasis, inflammation, repair, and remodeling. Hemostasis and the initial phases of inflammation in brain tissue are typical of all vascularized tissue, such as skin. However, distinct differences arise in brain tissue during the later stages of inflammation, repair, and remodeling, and closely parallel the changes of Alzheimer’s disease. Our hypothesis – Alzheimer’s disease is brain wound healing gone awry at least in some cases – could be tested by measuring progression with biomarkers for the four stages of wound healing in humans or appropriate animal models. Autopsy studies might be done. Chronic traumatic encephalopathy might also result from the brain wound healing process. PMID:27585229

  11. A novel cobiotic-based preventive approach against high-fat diet-induced adiposity, nonalcoholic fatty liver and gut derangement in mice.

    Science.gov (United States)

    Singh, D P; Khare, P; Zhu, J; Kondepudi, K K; Singh, J; Baboota, R K; Boparai, R K; Khardori, R; Chopra, K; Bishnoi, M

    2016-03-01

    High-fat diets (HFDs) induce systemic inflammation, gut microbial derangements and disturb metabolic homeostasis, resulting in weight gain, insulin resistance and nonalcoholic fatty liver (NAFL). Numerous antioxidants and prebiotic/probiotics per se may prevent HFD-associated comorbidities, but there are no reports related to their combination. In the present study, we aim to evaluate a cobiotic combination of lycopene (antioxidant) and isomalto-oligosaccharides (IMOs, a prebiotic) for prevention of HFD-induced alterations. Male Swiss albino mice were fed either normal pellet diet (NPD) or HFD and lycopene (5 and 10 mg kg(-1)), IMOs (0.5 and 1 g kg(-1)) or their combination for 12 weeks. Systemic adiposity, glucose tolerance, insulin sensitivity, feeding regulators in hypothalamus, hepatosteatosis and liver inflammation, cecal short chain fatty acids (SCFAs), serum inflammatory cytokines, gut morphology and alterations in selected gut microbes were studied. Lycopene, IMOs and their combination prevented weight gain, adiposity, improved adipose tissue fat mobilization and reduced insulin resistance. Hypothalamic orexigenic and anorectic genes have also been modulated by these treatments. Dietary interventions prevented NAFL-like symptoms and improved glucose homeostasis. Improvement in selected gut microbial abundance and SCFA concentration along with reduced systemic inflammation, metabolic endotoxemia and improved ileal and colonic health were observed in mice supplemented with lycopene, IMOs and their combination. Interestingly, cobiotic combination synergistically improved many of the HFD-induced alterations. The present work provide evidence that new approach based on cobiotic combination (antioxidant plus prebiotic) can be employed to develop novel class of functional foods for their application against HFD-associated pathological complications.

  12. MR image assessment of disc configuration and degree of anterior disc displacement in internal derangement related to age

    Energy Technology Data Exchange (ETDEWEB)

    Igarashi, Chinami; Kobayashi, Kaoru; Imanaka, Masahiro; Yuasa, Masao; Yamamoto, Akira [Tsurumi Univ., Yokohama (Japan). School of Dental Medicine

    1999-03-01

    This study was designed to evaluate the configuration of the articular disc and degree of anterior disc displacement on magnetic resonance (MR) imagings in temporomandibular joints (TMJs) with internal derangement. A total of 363 joints diagnosed as having anterior disc displacement with reduction (ADD w R) and 523 joints diagnosed as having anterior disc displacement without reduction (ADD wo R) by MR imaging were examined. These joints did not show severe osseous changes on the condylar head or glenoid fossa. We assessed the configuration of the articular disc and degree of anterior disc displacement. In the ADD w R group, 82.6% of the articular discs showed biconcave configuration; enlargement of the posterior band in 4.6%, biconvex configuration in 0.5%, and others in 10.7%. Moreover 62.5% of the discs showed a slight degree of anterior disc displacement; were 27.2% moderately displaced and were 10.2% severe displaced. The prevalence of slightly displaced discs was higher in the TMJs of cases over 50 years of age than in cases under 30 years in the ADD w R group. On the other hand, in the ADD wo R group 35.9% of the articular discs showed biconcave configuration; enlargement of the posterior band in 12.6%, biconvex configuration in 25.4%, and others in 22.3%. Furthermore, 4.4% of the discs were slightly displaced; 43.9% moderately displaced and 51.6% were severely displaced. The prevalence of severely displaced and deformed discs in joints of cases over 40 years of age was high in the ADD wo R group. The prevalence of slightly displaced biconcave discs was higher in the ADD w R group. The other hand, the prevalence of severely displaced deformed discs was higher in the ADD wo R group. MR findings of internal derangement of the TMJ were found to be significantly correlated with age. (author)

  13. Review: hemodynamic response to carbon monoxide

    Energy Technology Data Exchange (ETDEWEB)

    Penney, D.G.

    1988-04-01

    Historically, and at present, carbon monoxide is a major gaseous poison responsible for widespread morbidity and mortality. From threshold to maximal nonlethal levels, a variety of cardiovascular changes occur, both immediately and in the long term, whose homeostatic function it is to renormalize tissue oxygen delivery. However, notwithstanding numerous studies over the past century, the literature remains equivocal regarding the hemodynamic responses in animals and humans, although CO hypoxia is clearly different in several respects from hypoxic hypoxia. Factors complicating interpretation of experimental findings include species, CO dose level and rate, route of CO delivery, duration, level of exertion, state of consciousness, and anesthetic agent used. Augmented cardiac output usually observed with moderate COHb may be compromised in more sever poisoning for the same reasons, such that regional or global ischemia result. The hypotension usually seen in most animal studies is thought to be a primary cause of CNS damage resulting from acute CO poisoning, yet the exact mechanism(s) remains unproven in both animals and humans, as does the way in which CO produces hypotension. This review briefly summarizes the literature relevant to the short- and long-term hemodynamic responses reported in animals and humans. It concludes by presenting an overview using data from a single species in which the most complete work has been done to date.

  14. Cerebral hemodynamics and functional prognosis in hydrocephalus

    International Nuclear Information System (INIS)

    Hirai, Osamu; Nishikawa, Michio; Watanabe, Shu; Yamakawa, Hiroyasu; Kinoshita, Yoshimasa; Uno, Akira; Handa, Hajime

    1989-01-01

    The functional outcome of cerebral hemodynamics in the chronic stage of juvenile hydrocephalus was determined using single photon emission computed tomography (SPECT). Five patients including three with aqueductal stenosis, one with post-meningitic hydrocephalus, and one case with hydrocephalus having developed after repair of a huge occipital encephalocele. Early images of cerebral blood flow (CBF) were obtained 25 minutes after intravenous injection of 123-I-iodoamphetamine (IMP), and late images were scanned 3 hours later. Cerebral blood volume (CBV) was also measured using 99m Tc in three patients. Twenty cases with adult communicating hydrocephalus were also investigated from the point of view of shunt effectiveness. Although there was no remarkable change in the cerebrovascular bed in the juvenile cases, CBF of the remnant brain parenchyma was good irrespective of the degree of ventricular dilatation. There was a periventricular-related IMP uptake in each case; however, it somehow matched the ventricular span. Functional outcome one to 23 years after the initial shunt operation was good in every case, despite multiple shunt revisions. Redistribution on late images had no bearing on clinical states. In adult cases, 8 patients with effective shunting demonstrated a relatively localized periventricular low perfusion, with preoperative increased cerebrospinal fluid (CSF) pressure. On the contrary, 12 patients with no improvement with or without ventricular-reduced IMP uptake, despite low CSF pressure. The present study indicates that periventricular hemodynamics may play an important role in cerebral function compromised by hydrocephalus. (J.P.N.)

  15. Cerebral hemodynamics and functional prognosis in hydrocephalus

    Energy Technology Data Exchange (ETDEWEB)

    Hirai, Osamu; Nishikawa, Michio; Watanabe, Shu; Yamakawa, Hiroyasu; Kinoshita, Yoshimasa; Uno, Akira; Handa, Hajime (Hamamatsu Rosai Hospital, Shizuoka (Japan))

    1989-11-01

    The functional outcome of cerebral hemodynamics in the chronic stage of juvenile hydrocephalus was determined using single photon emission computed tomography (SPECT). Five patients including three with aqueductal stenosis, one with post-meningitic hydrocephalus, and one case with hydrocephalus having developed after repair of a huge occipital encephalocele. Early images of cerebral blood flow (CBF) were obtained 25 minutes after intravenous injection of 123-I-iodoamphetamine (IMP), and late images were scanned 3 hours later. Cerebral blood volume (CBV) was also measured using {sup 99m}Tc in three patients. Twenty cases with adult communicating hydrocephalus were also investigated from the point of view of shunt effectiveness. Although there was no remarkable change in the cerebrovascular bed in the juvenile cases, CBF of the remnant brain parenchyma was good irrespective of the degree of ventricular dilatation. There was a periventricular-related IMP uptake in each case; however, it somehow matched the ventricular span. Functional outcome one to 23 years after the initial shunt operation was good in every case, despite multiple shunt revisions. Redistribution on late images had no bearing on clinical states. In adult cases, 8 patients with effective shunting demonstrated a relatively localized periventricular low perfusion, with preoperative increased cerebrospinal fluid (CSF) pressure. On the contrary, 12 patients with no improvement with or without ventricular-reduced IMP uptake, despite low CSF pressure. The present study indicates that periventricular hemodynamics may play an important role in cerebral function compromised by hydrocephalus. (J.P.N.).

  16. Hemodynamic Simulations in Dialysis Access Fistulae

    Science.gov (United States)

    McGah, Patrick; Leotta, Daniel; Beach, Kirk; Riley, James; Aliseda, Alberto

    2010-11-01

    Arteriovenous fistulae are created surgically to provide adequate access for dialysis in patients with End-Stage Renal Disease. It has long been hypothesized that the hemodynamic and mechanical forces (such as wall shear stress, wall stretch, or flow- induced wall vibrations) constitute the primary external influence on the remodeling process. Given that nearly 50% of fistulae fail after one year, understanding fistulae hemodynamics is an important step toward improving patency in the clinic. We perform numerical simulations of the flow in patient-specific models of AV fistulae reconstructed from 3D ultrasound scans with physiologically-realistic boundary conditions also obtained from Doppler ultrasound. Comparison of the flow features in different geometries and configurations e.g. end-to-side vs. side-to-side, with the in vivo longitudinal outcomes will allow us to hypothesize which flow conditions are conducive to fistulae success or failure. The flow inertia and pulsatility in the simulations (mean Re 700, max Re 2000, Wo 4) give rise to complex secondary flows and coherent vortices, further complicating the spatio- temporal variability of the wall pressure and shear stresses. Even in mature fistulae, the anastomotic regions are subjected to non-physiological shear stresses (>10.12pcPa) which may potentially lead to complications.

  17. Patient-Specific Modeling of Intraventricular Hemodynamics

    Science.gov (United States)

    Vedula, Vijay; Marsden, Alison

    2017-11-01

    Heart disease is the one of the leading causes of death in the world. Apart from malfunctions in electrophysiology and myocardial mechanics, abnormal hemodynamics is a major factor attributed to heart disease across all ages. Computer simulations offer an efficient means to accurately reproduce in vivo flow conditions and also make predictions of post-operative outcomes and disease progression. We present an experimentally validated computational framework for performing patient-specific modeling of intraventricular hemodynamics. Our modeling framework employs the SimVascular open source software to build an anatomic model and employs robust image registration methods to extract ventricular motion from the image data. We then employ a stabilized finite element solver to simulate blood flow in the ventricles, solving the Navier-Stokes equations in arbitrary Lagrangian-Eulerian (ALE) coordinates by prescribing the wall motion extracted during registration. We model the fluid-structure interaction effects of the cardiac valves using an immersed boundary method and discuss the potential application of this methodology in single ventricle physiology and trans-catheter aortic valve replacement (TAVR). This research is supported in part by the Stanford Child Health Research Institute and the Stanford NIH-NCATS-CTSA through Grant UL1 TR001085 and partly through NIH NHLBI R01 Grant 5R01HL129727-02.

  18. Effect of oxymetazoline nasal spray on intraocular pressure and retrobulbar hemodynamics.

    Science.gov (United States)

    Arikan, Osman Kursat; Akarsu, Cengiz; Unal, Birsen; Ergin, Ahmet; Koç, Can

    2006-02-01

    To determine the effect of oxymetazoline nasal spray on intraocular pressure and retrobulbar hemodynamics in patients with open-angle glaucoma and to compare the results with those measured in healthy control participants. Controlled, prospective clinical trial. University hospital. Thirty patients with open-angle glaucoma and 30 healthy volunteers as controls were topically self-administered oxymetazoline nasal spray three times a day (one spray in each nostril of 0.05% concentration) for 5 days continuously. Intraocular pressure and retrobulbar hemodynamics were measured in glaucomatous and normal eyes at baseline and at the end of oxymetazoline application . Oxymetazoline nasal spray lowered intraocular pressure significantly in both the glaucoma group (p = .02) and the control group (p = .001) after 5 days of treatment. The systemic parameters in the glaucoma and control groups (systolic blood pressure, p = .14 and p = .17; diastolic blood pressure, p = .18 and p = .49; and pulse rate, p = .06 and p = .50, respectively) did not show statistically significant differences during the study period. Additionally, except with a significant decrease in the resistivity index of the central retinal artery in the glaucoma patients (p = .001), oxymetazoline nasal spray did not result in any significant changes in the retrobulbar hemodynamics in both the glaucoma and control groups. This study showed that a 5-day treatment with oxymetazoline nasal spray reduced intraocular pressure in both healthy controls and patients with glaucoma under treatment. In addition, it had no significant adverse effects on the retrobulbar hemodynamics.

  19. Concurrent OCT imaging of stimulus evoked retinal neural activation and hemodynamic responses

    Science.gov (United States)

    Son, Taeyoon; Wang, Benquan; Lu, Yiming; Chen, Yanjun; Cao, Dingcai; Yao, Xincheng

    2017-02-01

    It is well established that major retinal diseases involve distortions of the retinal neural physiology and blood vascular structures. However, the details of distortions in retinal neurovascular coupling associated with major eye diseases are not well understood. In this study, a multi-modal optical coherence tomography (OCT) imaging system was developed to enable concurrent imaging of retinal neural activity and vascular hemodynamics. Flicker light stimulation was applied to mouse retinas to evoke retinal neural responses and hemodynamic changes. The OCT images were acquired continuously during the pre-stimulation, light-stimulation, and post-stimulation phases. Stimulus-evoked intrinsic optical signals (IOSs) and hemodynamic changes were observed over time in blood-free and blood regions, respectively. Rapid IOSs change occurred almost immediately after stimulation. Both positive and negative signals were observed in adjacent retinal areas. The hemodynamic changes showed time delays after stimulation. The signal magnitudes induced by light stimulation were observed in blood regions and did not show significant changes in blood-free regions. These differences may arise from different mechanisms in blood vessels and neural tissues in response to light stimulation. These characteristics agreed well with our previous observations in mouse retinas. Further development of the multimodal OCT may provide a new imaging method for studying how retinal structures and metabolic and neural functions are affected by age-related macular degeneration (AMD), glaucoma, diabetic retinopathy (DR), and other diseases, which promises novel noninvasive biomarkers for early disease detection and reliable treatment evaluations of eye diseases.

  20. The Effect of Neuraxial Anesthesia on Maternal Cerebral Hemodynamics

    NARCIS (Netherlands)

    Postma, Ineke R.; van Veen, Teelkien R.; Mears, Scott L.; Zeeman, Gerda G.; Haeri, Sina; Belfort, Michael A.

    2014-01-01

    Objective Neuraxial anesthesia is known to reduce sympathetic tone and mean arterial pressure. Effects on cerebral hemodynamics in pregnancy are not well known. We hypothesize that cerebral hemodynamic parameters will change with respect to baseline following regional analgesia/anesthesia. Study

  1. Advanced Hemodynamic Management in Patients with Septic Shock.

    Science.gov (United States)

    Saugel, Bernd; Huber, Wolfgang; Nierhaus, Axel; Kluge, Stefan; Reuter, Daniel A; Wagner, Julia Y

    2016-01-01

    In patients with sepsis and septic shock, the hemodynamic management in both early and later phases of these "organ dysfunction syndromes" is a key therapeutic component. It needs, however, to be differentiated between "early goal-directed therapy" (EGDT) as proposed for the first 6 hours of emergency department treatment by Rivers et al. in 2001 and "hemodynamic management" using advanced hemodynamic monitoring in the intensive care unit (ICU). Recent large trials demonstrated that nowadays protocolized EGDT does not seem to be superior to "usual care" in terms of a reduction in mortality in emergency department patients with early identified septic shock who promptly receive antibiotic therapy and fluid resuscitation. "Hemodynamic management" comprises (a) making the diagnosis of septic shock as one differential diagnosis of circulatory shock, (b) assessing the hemodynamic status including the identification of therapeutic conflicts, and (c) guiding therapeutic interventions. We propose two algorithms for hemodynamic management using transpulmonary thermodilution-derived variables aiming to optimize the cardiocirculatory and pulmonary status in adult ICU patients with septic shock. The complexity and heterogeneity of patients with septic shock implies that individualized approaches for hemodynamic management are mandatory. Defining individual hemodynamic target values for patients with septic shock in different phases of the disease must be the focus of future studies.

  2. Hemodynamic effects of sevoflurane versus propofol anesthesia for ...

    African Journals Online (AJOL)

    Adele

    cryotherapy, radiofrequency does not induce hemodynamic instability. In an animal study, hepatic artery blood flow and peripheral blood pressure did not change significantly during peritoneal insufflation for radiofrequency ablation surgery.8. We did not intend to investigate the effects of LRFA itself on the hemodynamics.

  3. New approach to intracardiac hemodynamic measurements in small animals

    DEFF Research Database (Denmark)

    Eskesen, Kristian; Olsen, Niels T; Dimaano, Veronica L

    2012-01-01

    Invasive measurements of intracardiac hemodynamics in animal models have allowed important advances in the understanding of cardiac disease. Currently they are performed either through a carotid arteriotomy or via a thoracotomy and apical insertion. Both of these techniques have disadvantages...... and are not conducive to repeated measurements. Therefore, the purpose of this study was to develop a new technique for measuring intracardiac hemodynamics....

  4. Invasive hemodynamic characterization of heart failure with preserved ejection fraction

    DEFF Research Database (Denmark)

    Andersen, Mads Jønsson; Borlaug, Barry A

    2014-01-01

    Recent hemodynamic studies have advanced our understanding of heart failure with preserved ejection fraction (HFpEF). Despite improved pathophysiologic insight, clinical trials have failed to identify an effective treatment for HFpEF. Invasive hemodynamic assessment can diagnose or exclude HFp...... of pathophysiological differences and inform the design and entry criteria for future trials....

  5. Diastolic pressure underestimates age-related hemodynamic impairment.

    Science.gov (United States)

    Galarza, C R; Alfie, J; Waisman, G D; Mayorga, L M; Cámera, L A; del Río, M; Vasvari, F; Limansky, R; Farías, J; Tessler, J; Cámera, M I

    1997-10-01

    It has been hypothesized that as large arteries become more rigid with age, the pattern of hypertension changes from diastolic to systolic. Thus, diastolic blood pressure (DBP) may lose its ability to reflect the increase in vascular resistance with age. To assess this, we studied the age-related changes in blood pressure pattern and its steady-state and pulsatile determinants. We performed an epidemiological analysis based on a national survey of 10,462 subjects from Argentina. A hemodynamic analysis (impedance cardiography) was then carried out in 636 consecutive hypertensive patients (age, 25 to 74 years). Whereas the rate of increment in the prevalence of mild to moderate hypertension (MMH) reached a plateau after the sixth decade, isolated and borderline systolic forms of hypertension began a steep and sustained rise. Among patients with MMH, DBP remained stable from the third to the seventh decade, whereas SBP maintained a sustained increase. Despite similar DBP, the systemic vascular resistance index increased 47% (P<.01) and the cardiac index decreased 27% (P<.01), whereas the ratio of stroke volume to pulse pressure, an index of arterial compliance, decreased 45% (P<.01). However, there were no significant differences between older patients with MMH and those with isolated systolic hypertension in the level of SBP, vascular resistance, stroke volume, and cardiac index. Compared with age-matched normotensive control subjects, the ratio of stroke volume to pulse pressure was much more reduced in isolated systolic hypertension (48%) than in MMH (30%). In summary, the present study, carried out in a large sample of hypertensive subjects with a wide age range, showed a simultaneous impairment in vascular resistance and arterial compliance associated with aging in different patterns of hypertension. The magnitude of these changes, with opposite effects on DBP but additive effects on SBP, suggests that a hemodynamic mechanism could determine the transition in the

  6. Hemodynamic Stability during Induction of Anesthesia in Elderly Patients: Propofol + Ketamine versus Propofol + Etomidate

    Directory of Open Access Journals (Sweden)

    Hamzeh Hosseinzadeh

    2013-07-01

    Conclusion: Both methods of induction -ketamine + propofol and etomidate + propofol- are effective in maintaining hemodynamic stability and preventing hemodynamic changes due to propofol administration.

  7. Relationships between thyroid function and autoimmunity with metabolic derangement at the onset of type 1 diabetes: a cross-sectional and longitudinal study.

    Science.gov (United States)

    Balsamo, C; Zucchini, S; Maltoni, G; Rollo, A; Martini, A L; Mazzanti, L; Pession, A; Cassio, A

    2015-06-01

    Type 1 diabetes (T1DM) is an autoimmune disease often associated with thyroid abnormalities. We investigated the correlation between thyroid function and metabolic derangement at onset and the influence of autoimmunity on thyroid function at onset and subsequently. We evaluated 152 patients diagnosed with T1DM between 2000 and 2012 at onset and during a mean follow-up of 5.45 ± 2.8 years. Thyroid function at onset was correlated with metabolic derangement (degree of acidosis, metabolic control and adrenal function) and compared with that of 78 healthy children. Follow-up consisted of regular evaluation of thyroid function and autoimmunity. Thyroid hormonal pattern was not influenced at onset by thyroid autoimmunity, but only by metabolic derangement: pH and base excess in fact were significantly lower in patients with impaired thyroid function (p thyroid function at onset showed a reduced conversion from FT4 to FT3 compared to nondiabetic children (FT3/FT4 0.3 ± 0.4 in the control group, 0.24 ± 0.4 in diabetic patients, p Thyroid abnormalities related to metabolic derangement disappeared during follow-up. Patients with thyroid antibodies at T1DM onset were at higher risk to require levothyroxine treatment during follow-up (p Thyroid function at T1DM onset is mainly influenced by metabolic derangement, irrespective of thyroid autoimmunity. Antithyroid antibodies evaluation at T1DM onset may be helpful to define which patients are at higher risk of developing hypothyroidism.

  8. Evaluation of the relation between the horizontal condylar angle and the internal derangement of the TMJ - a magnetic resonance imaging study

    Energy Technology Data Exchange (ETDEWEB)

    Crusoe-Rebello, Ieda Margarida Rocha [Fundacao de Amparo a Pesquisa do Estado da Bahia (FAPESB), Salvador (Brazil); Campos, Paulo Sergio Flores; Rubira, Izabel Regina Fischer [Sao Paulo Univ., SP (Brazil). Faculdade de Odontologia. Dept. of Propedeutica e Clinica Integrada; Panella, Jurandyr [Sao Paulo Univ., SP (Brazil). Faculdade de Odontologia. Dept. de Radiologia; Mendes, Carlos Mauricio Cardeal [Bahia Univ., Salvador, BA (Brazil). Faculdade de Medicine

    2003-06-01

    This research aimed at assessing the relation between the horizontal condylar angle (HCA) and the internal derangement (ID) of the temporomandibular joint (TMJ), as a result of interference by the T MJ disk, in individuals undergoing magnetic resonance (MR) scans. The sample included a total of 144 TMJs (sagittal and coronal views) of 72 subjects, 15 of whom were male and 57 female, with ages ranging from 15 to 70. The scans were made in a Signa system model at a magnetic field magnitude of 1.5 T. Sixty-eight TMJs were found to be normal, while 46 showed anterior displacement with reduction. Of these, 41 had some kind of adaptive change in the condyle, while 5 showed degenerative changes. Anterior displacement without reduction was found in 29 joints, 12 of which showed adaptive changes in the condyle, while 17 showed degenerative changes. Only one posterior displacement of the articular disk was recorded. For the TMJs in which disk displacement was found, such values achieved 24.69 deg on the right side, and 22.94 deg on the left side. Hence, it was possible for us to conclude that the HCA tends to increase in those TMJs where ID is present. For contralateral TMJs, a strong association was observed between HCA values (57.8%), state of normality (69.7%), and ID (66.7%). To corroborate such findings, a correlation between contralateral HCA values (63.31%) and the diagnosis for contralateral TMJs (68.05%) was determined. Thus, we could infer that there is a tendency between contralateral TMJs to share characteristics and conditions. (author)

  9. Hemodynamic traveling waves in human visual cortex.

    Directory of Open Access Journals (Sweden)

    Kevin M Aquino

    Full Text Available Functional MRI (fMRI experiments rely on precise characterization of the blood oxygen level dependent (BOLD signal. As the spatial resolution of fMRI reaches the sub-millimeter range, the need for quantitative modelling of spatiotemporal properties of this hemodynamic signal has become pressing. Here, we find that a detailed physiologically-based model of spatiotemporal BOLD responses predicts traveling waves with velocities and spatial ranges in empirically observable ranges. Two measurable parameters, related to physiology, characterize these waves: wave velocity and damping rate. To test these predictions, high-resolution fMRI data are acquired from subjects viewing discrete visual stimuli. Predictions and experiment show strong agreement, in particular confirming BOLD waves propagating for at least 5-10 mm across the cortical surface at speeds of 2-12 mm s-1. These observations enable fundamentally new approaches to fMRI analysis, crucial for fMRI data acquired at high spatial resolution.

  10. Hemodynamic characteristics of early stage hepatocellular carcinoma

    International Nuclear Information System (INIS)

    Kudo, Masatoshi; Tomita, Shusuke; Tochio, Hitoshi

    1992-01-01

    Hemodynamic characteristics were studied by using in vivo vascular imaging techniques in 17 resected early stage hepatocellular carcinoma (e-HCC) by comparing them with 49 resected advanced HCCs (ad-HCC) less than 3 cm in diameter. In this study, e-HCC was defined as the nodule being uniformly composed of well-differentiated HCC or adenomatous hyperplastic nodule containing well-differentiated HCC foci within the nodule. In vivo vascular imaging techniques are as follows; US angiography with intraarterial CO 2 microbubbles were performed to assess the tumor arterial vascularity, and CT during arterial portography (CTAP) was performed to assess the portal perfusion within the nodule. Of 17 e-HCC nodules 5 were hypervascular, 5 were isovascular, 4 were hypovascular, and 3 were vascular spot in hypovascular pattern in contrast to 49 ad-HCC nodules, 43 of which were hypervascular and 6 were isovascular. Of 14 e-HCCs, 9 nodules showed perfusion defect and 5 did not on CTAP, whereas all 37 ad-HCCs on which CTAP was performed, showed perfusion defect. Forty-one percent (7/17) of e-HCC showed fatty metamorphosis in contrast to 8% (4/49) of ad-HCC. In conclusion, hemodynamic characteristics of e-HCC are summarized as follows. (1) Arterial tumor neovascularization is relatively low. (2) Portal perfusion is present in some of e-HCC cases. (3) Hypoperfusion state both from arterial and portal supply is present in some of e-HCC cases. (4) Vascular spot in hypovascular pattern is characteristic arterial pattern in AH containing HCC foci. (5) Fatty metamorphosis may be related with hypoperfusion state of the nodule in e-HCC. (author)

  11. Hemodynamic management of septic shock: is it time for "individualized goal-directed hemodynamic therapy" and for specifically targeting the microcirculation?

    Science.gov (United States)

    Saugel, Bernd; Trepte, Constantin J; Heckel, Kai; Wagner, Julia Y; Reuter, Daniel A

    2015-06-01

    Septic shock is a life-threatening condition in both critically ill medical patients and surgical patients during the perioperative phase. In septic shock, specific alterations in global cardiovascular dynamics (i.e., the macrocirculation) and in the microcirculatory blood flow (i.e., the microcirculation) have been described. However, the presence and degree of microcirculatory failure are in part independent from systemic macrohemodynamic variables. Macrocirculatory and microcirculatory failure can independently induce organ dysfunction. We review current diagnostic and therapeutic approaches for the assessment and optimization of both the macrocirculation and the microcirculation in septic shock. There are various technologies for the determination of macrocirculatory hemodynamic variables. We discuss the data on early goal-directed therapy for the resuscitation of the macrocirculation. In addition, we describe the concept of "individualized goal-directed hemodynamic therapy." Technologies to assess the local microcirculation are also available. However, adequate resuscitation goals for the optimization of the microcirculation still need to be defined. At present, we are not ready to specifically monitor and target the microcirculation in clinical routine outside studies. In the future, concepts for an integrative approach for individualized hemodynamic management of the macrocirculation and in parallel the microcirculation might constitute a huge opportunity to define additional resuscitation end points in septic shock.

  12. Ionizing radiation occupational exposure in the hemodynamics services

    International Nuclear Information System (INIS)

    Gronchi, Claudia Carla

    2004-01-01

    The purpose of this research is to study the ionizing radiation occupational exposure in the hemodynamic services of two large scale hospitals (Hospital A and Hospital B) of the Sao Paulo city. The research looked into annual doses that 279 professionals of the hemodynamic services were exposed to between 1991 and 2002. The data analyzed was collected from the database of the Instituto de Pesquisas Energeticas e Nucleares (IPEN) for Hospital A, and from the Radiological Protection Department of Hospital B. Besides this, measures of hands and crystalline lens equivalent doses were performed during hemodynamic procedures of the physicians, assistant physicians and nursing assistants with TL dosimeters (CaSO 4 :Dy + Teflon R) produced at IPEN. The safety procedures adopted by the hospitals were verified with the aid of a specific questionnaire for the hemodynamic services. Finally, a profile of the professionals that work in cardiac catheterism laboratories of the hemodynamic services was delineated, considering the variables of individual monitoring time, age and sex. This study allowed for observation of the behavior of the professionals' annual doses of these hemodynamic services in relation to the Comissao Nacional de Energia Nuclear and the Secretaria de Vigilancia Sanitaria limits. It showed that the annual doses of the same specialized occupations would vary from one hospital to another. It further showed the need of individual monitoring of the physicians' unprotected body parts (hands and crystalline lens) during the hemodynamic procedures. (author)

  13. Correlation between Eminence Steepness and Condyle Disk Movements in Temporomandibular Joints Affected by Internal Derangements Using Magnetic Resonance Imaging

    Directory of Open Access Journals (Sweden)

    Nilofar Mofidi

    2013-02-01

    Full Text Available Background and Aims: Internal derangement of the Temporomandibular joint (TMJ is the most common form of Temporomandibular disorders, which represents an abnormal internal strucural and functional change of the disk, as well as an abnormal relationship of the disk to the condyle, glenoid fossa and articular eminence when the teeth are in the closed- mouth position. The aim of this study was to evaluate the correlation between eminence steepness and condyle disk movements in TMJs affected by internal derangements using magnetic resonance imaging (MRI. Materials and Methods: In this cross-sectional study, digital MRI files of 90 joints belong to 45 patients in open and closed-mouth positions were evaluated. Patients were subdivided into two groups: 64 individuals with anterior diskdisplacement with reduction and 26 individuals with anterior disk displacement without reduction. Appropriate oblique sagittal sections were selected and printed. Outlines of the fossa, eminence, condyle and disk were traced on matte acetate sheets and evaluated by an oral and maxillofacial radiologist and a postgraduate student of oral and maxillofacial radiology. Disk rotation, condyle rotation, condyle translation and eminence steepness were measured.The data were analyzed using T-test.Results: In this study, no significant difference was found in measurements between the two groups, (for steepness P=0.64, for Disc rotation P=0.77, for condyle rotation P=0.28 and for condyle translation P=0.12. Disk rotation showed statistically significant correlation with eminence steepness in the anterior disk displacement with reduction group 34 .Although this correlation was weak (r=0.27 (P>0.05. No statistically significant correlations were found between other variables and eminence steepness in this group (for condyle rotation P=0.3 and for condyle translation P=0.98. Disk rotation and condyle translation had statistically significant relationship in the anterior disk

  14. Permanent education that approaches radiation protection in hemodynamic service

    International Nuclear Information System (INIS)

    Flor, Rita de Cassia; Anjos, Djeniffer Valdirene dos

    2011-01-01

    In the hemodynamic services that apply ionizing radiation yet exist the necessity of capacitation of workers for actuation in those areas. So, this qualitative study performed in a hemodynamic service at Sao Jose, Santa Catarina, Brazil, had the objective to analyse how are developed the permanent education programs and the real necessity of workers. The results have shown that the workers are longing for their qualification and formation, as generally they are admitted with not any qualification for those services. So, the workers that realize the on duty hemodynamic service praxis must do it in a conscious manner and the E P is a way for to adopt good practice in radiological protection

  15. Hemodynamic correction of univentricular congenital heart diseases: the role of additional sources of pulmonary blood flow

    Directory of Open Access Journals (Sweden)

    Ю. Н. Горбатых

    2015-10-01

    Full Text Available Analysis of the impact of additional sources of pulmonary blood flow on the outcomes of hemodynamic correction of univentricular congenital heart disease is presented. From 2003 to 2010 31 patients received a bidirectional cavopulmonary shunt (BCPS with/without preservation of additional pulmonary blood flow sources. The latter were preserved in 18 patients (1st group and eliminated in 13 patients (2nd group. Later on all patients had Fontan procedure. Our results showed no significant impact of additional pulmonary blood flow sources on the system ventricle function and systemic AV valve regurgitation. Preservation of adequate additional pulmonary blood flow during BCPS promotes pulmonary arterial growth and increases the degree of freedom from operative intervention, while optimizing hemodynamic features of Fontan-borderline patients.

  16. Hemodynamic Change in Pulmonary Vein Stenosis after Radiofrequency Ablation: Assessment with Magnetic Resonance Angiography

    Energy Technology Data Exchange (ETDEWEB)

    Yun, Doyoung; Jung, Jung Im; Oh, Yong Seog; Youn, Ho Joong [Seoul St. Mary' s Hospital, College of Medicine, The Catholic University of Korea, Seoul (Korea, Republic of)

    2012-11-15

    We present a case of pulmonary vein (PV) stenosis after radio-frequency (RF) ablation, in which a hemodynamic change in the pulmonary artery was similar to that of congenital PV atresia on time-resolved contrast-enhanced magnetic resonance angiography (TR-MRA). A 48-year-old man underwent RF ablation due to atrial fibrillation. The patient subsequently complained of hemoptysis, dyspnea on exertion, and right chest pain. Right PV stenosis after catheter ablation was diagnosed through chest computed tomography and lung perfusion scan. Pulmonary TR-MRA revealed the pulmonary artery via systemic arterial collaterals and draining systemic collateral veins. On a velocity-encoded cine image, the flow direction of the right pulmonary artery was reversed in the diastolic phase and the left pulmonary artery demonstrated continuous forward flow throughout the cardiac cycle. These hemodynamic changes were similar to those seen in congenital unilateral PV atresia.

  17. Hemodynamic and respiratory effects of pneumoperitoneum and PEEP during laparoscopic pelvic lymphadenectomy in dogs.

    Science.gov (United States)

    Luz, C M; Polarz, H; Böhrer, H; Hundt, G; Dörsam, J; Martin, E

    1994-01-01

    Extended laparoscopic operations are being performed increasingly in high-risk patients. To assess the effects of increased intraabdominal pressure (IAP) and positive end-expiratory pressure (PEEP) on the hemodynamic and respiratory system during extended procedures a carbon dioxide pneumoperitoneum was artificially induced in 10 dogs undergoing laparoscopic pelvic lymphadenectomy. An increase in IAP up to 15 mmHg had no negative effect on the cardiovascular system. However, the combination of an increased IAP (10-15 mmHg) with PEEP (8 cmH2O) markedly depressed the hemodynamic variables. Measurement of arterial carbon dioxide and fractional end-tidal carbon dioxide revealed significant CO2 retention. We conclude from the results that laparoscopic pelvic lymphadenectomy should be performed in high-risk patients only under general anesthesia with expanded cardiopulmonary monitoring.

  18. Effect on hemodynamics of a liquid meal alone and in combination with propranolol in cirrhosis

    DEFF Research Database (Denmark)

    Bendtsen, F; Simonsen, L; Henriksen, Jens Henrik Sahl

    1992-01-01

    Thirteen patients with alcoholic cirrhosis had splanchnic and systemic hemodynamics assessed before and after ingestion of a standard liquid meal of 700 kcal (consisting of isocaloric proteins, lipids, and carbohydrates). Half of the patients (n = 6) were randomized to a treatment group receiving...... intravenous infusion of propranolol in combination with the meal. No significant effects were observed on systemic hemodynamics after the meal alone. Heart rate (-14%; P less than 0.01) and cardiac index (-24%; P less than 0.01) decreased after meal in combination with propranolol. The mean hepatic venous...... pressure gradient increased significantly after ingestion of the meal alone with a maximal effect after 30 minutes (+13%; P less than 0.05) and returned to baseline values after 2 hours. Meal in combination with propranolol had no significant effect on the hepatic venous pressure gradient. Hepatic blood...

  19. Journal of Clinical Monitoring and Computing 2017 end of year summary: cardiovascular and hemodynamic monitoring.

    Science.gov (United States)

    Saugel, Bernd; Bendjelid, Karim; Critchley, Lester A H; Scheeren, Thomas W L

    2018-02-26

    Hemodynamic monitoring provides the basis for the optimization of cardiovascular dynamics in intensive care medicine and anesthesiology. The Journal of Clinical Monitoring and Computing (JCMC) is an ideal platform to publish research related to hemodynamic monitoring technologies, cardiovascular (patho)physiology, and hemodynamic treatment strategies. In this review, we discuss selected papers published on cardiovascular and hemodynamic monitoring in the JCMC in 2017.

  20. Preventive role of exercise training in autonomic, hemodynamic, and metabolic parameters in rats under high risk of metabolic syndrome development.

    Science.gov (United States)

    Moraes-Silva, Ivana Cinthya; Mostarda, Cristiano; Moreira, Edson Dias; Silva, Kleiton Augusto Santos; dos Santos, Fernando; de Angelis, Kátia; Farah, Vera de Moura Azevedo; Irigoyen, Maria Claudia

    2013-03-15

    High fructose consumption contributes to metabolic syndrome incidence, whereas exercise training promotes several beneficial adaptations. In this study, we demonstrated the preventive role of exercise training in the metabolic syndrome derangements in a rat model. Wistar rats receiving fructose overload in drinking water (100 g/l) were concomitantly trained on a treadmill (FT) or kept sedentary (F) for 10 wk. Control rats treated with normal water were also submitted to exercise training (CT) or sedentarism (C). Metabolic evaluations consisted of the Lee index and glycemia and insulin tolerance test (kITT). Blood pressure (BP) was directly measured, whereas heart rate (HR) and BP variabilities were evaluated in time and frequency domains. Renal sympathetic nerve activity was also recorded. F rats presented significant alterations compared with all the other groups in insulin resistance (in mg · dl(-1) · min(-1): F: 3.4 ± 0.2; C: 4.7 ± 0.2; CT: 5.0 ± 0.5 FT: 4.6 ± 0.4), mean BP (in mmHG: F: 117 ± 2; C: 100 ± 2; CT: 98 ± 2; FT: 105 ± 2), and Lee index (in g/mm: F = 0.31 ± 0.001; C = 0.29 ± 0.001; CT = 0.27 ± 0.002; FT = 0.28 ± 0.002), confirming the metabolic syndrome diagnosis. Exercise training blunted all these derangements. Additionally, FS group presented autonomic dysfunction in relation to the others, as seen by an ≈ 50% decrease in baroreflex sensitivity and 24% in HR variability, and increases in sympathovagal balance (140%) and in renal sympathetic nerve activity (45%). These impairments were not observed in FT group, as well as in C and CT. Correlation analysis showed that both Lee index and kITT were associated with vagal impairment caused by fructose. Therefore, exercise training plays a preventive role in both autonomic and hemodynamic alterations related to the excessive fructose consumption.

  1. Biochemical derangements prior to emergency laparotomy at Queen Elizabeth Central Hospital, Blantyre, Malawi: A cross-sectional pilot study.

    Science.gov (United States)

    Williams, Mark G

    2017-03-01

    The aim of this study was to examine biochemical investigations not routinely performed prior to emergency laparotomy in patients at Queen Elizabeth Central Hospital, a low-resource public hospital in Blantyre, Malawi. A prospective cross-sectional study of adults (N = 15) needing emergency laparotomy over a 4-week period were studied at Queen Elizabeth Central Hospital. Biochemical investigations, not routinely performed for economic reasons, were performed preoperatively; these included sodium, potassium, chloride, carbon dioxide, urea, and calcium levels. Gastrointestinal pathology was predominant among the emergency laparotomies performed. Large bowel obstruction and bowel perforation secondary to typhoid were most frequent. Clinically significant biochemical derangements among the study patients were as follows: cases of moderate-to-severe hypokalaemia (n = 2), severe hyponatraemia (n = 1), moderate hypernatraemia (n = 1), and severe hypocalcaemia (n = 1). The most frequent abnormalities seen were uraemia and hypochloraemia (n = 11). Accurate electrolyte estimation in critically ill preoperative patients is desireable for optimal perioperative management but frequently absent in resource-challenged environments.

  2. An ex vivo study on immunohistochemical localization of MMP-7 and MMP-9 in temporomandibular joint discs with internal derangement

    Directory of Open Access Journals (Sweden)

    C. Loreto

    2013-04-01

    Full Text Available Internal derangement (ID is among the most common disorders of the temporomandibular joint (TMJ. Previous research by our group highlighted a correlation between apoptosis and TMJ ID. Metalloproteinases (MMP-7 and -9 have been shown to play an important role in extracellular matrix ECM homeostasis and, through it, in joint disc remodelling. The immunohistochemical expression of MMP-7 and -9 was investigated in discs from patients with TMJ ID and from healthy donors and compared with the degree of histological tissue degeneration. The collagen fibre arrangement in pathological discs exhibited varying degrees of disruption. New vessels were consistently detected; endothelial cells from these vessels were immunolabelled with both MMP-7 and MMP-9. More or less intense MMP-7 and MMP-9 immunolabelling was detected in the cytoplasm of disc cells from all patients. MMP-7 and MMP-9 immunostaining was significantly different between pathological and normal discs and correlated with the extent of histopathological degeneration. MMP-7 and MMP-9 upregulation in discs from patients with TMJ ID demonstrates their involvement in disc damage in this disorder. A greater understanding of these processes could help identify ways to curb MMP overproduction without affecting their tissue remodelling action. The design of specific inhibitors for these MMPs would not only help to gain insights into the biological roles of MMPs, but would also aid in developing therapeutic interventions for diseases associated with abnormal ECM degradation.

  3. Hemodynamic changes during robotic radical prostatectomy

    Directory of Open Access Journals (Sweden)

    Vanlal Darlong

    2012-01-01

    Full Text Available Background: Effect on hemodynamic changes and experience of robot-assisted laparoscopic radical prostatectomy (RALRP in steep Trendelenburg position (45° with high-pressure CO 2 pneumoperitoneum is very limited. Therefore, we planned this prospective clinical trial to study the effect of steep Tredelenburg position with high-pressure CO 2 pneumoperitoneum on hemodynamic parameters in a patient undergoing RALRP using FloTrac/Vigileo™1.10. Methods: After ethical approval and informed consent, 15 patients scheduled for RALRP were included in the study. In the operation room, after attaching standard monitors, the radial artery was cannulated. Anesthesia was induced with fentanyl (2 μg/kg and thiopentone (4-7 mg/kg, and tracheal intubation was facilitated by vecuronium bromide (0.1 mg/kg. The patient′s right internal jugular vein was cannulated and the Pre Sep™ central venous oximetry catheter was connected to it. Anesthesia was maintained with isoflurane in oxygen and nitrous oxide and intermittent boluses of vecuronium. Intermittent positive-pressure ventilation was provided to maintain normocapnea. After CO 2 pneumoperitoneum, position of the patient was gradually changed to 45° Trendelenburg over 5 min. The robot was then docked and the robot-assisted surgery started. Intraoperative monitoring included central venous pressure (CVP, stroke volume (SV, stroke volume variation (SVV, cardiac output (CO, cardiac index (CI and central venous oxygen saturation (ScvO 2 . Results: After induction of anesthesia, heart rate (HR, SV, CO and CI were decreased significantly from the baseline value (P>0.05. SV, CO and CI further decreased significantly after creating pneumoperitoneum (P>0.05. At the 45° Trendelenburg position, HR, SV, CO and CI were significantly decreased compared with baseline. Thereafter, CO and CI were persistently low throughout the 45° Trendelenburg position (P=0.001. HR at 20 min and 1 h, SV and mean arterial blood pressure

  4. Hemodynamic coherence and the rationale for monitoring the microcirculation

    NARCIS (Netherlands)

    Ince, Can

    2015-01-01

    This article presents a personal viewpoint of the shortcoming of conventional hemodynamic resuscitation procedures in achieving organ perfusion and tissue oxygenation following conditions of shock and cardiovascular compromise, and why it is important to monitor the microcirculation in such

  5. QUANTITATIVE PARAMETERS OF NUCLEAR AND FREE CELL DNA IN NEWBORN BABIES WITH CLINICAL MANIFESTATIONS OF ADAPTATION DERANGEMENT IN EARLY NEONATAL PERIOD

    Directory of Open Access Journals (Sweden)

    V.V. Sofronov

    2006-01-01

    Full Text Available In the paper were presented the results of an investigation of the nucleus area and metabolism DNA parameters (the level of nuclear DNA uptake, the level of a chromatin condensation and the concentration of plasma free cell DNA in newborns with clinical manifestations of adaptation derangement (a perinatal CNS damage, an intrauterine pneumonia and a neonatal pneumopathy in early neonatal period. In all cases the disorders of a DNA metabolism was obtained. However, the greatest divergence of all investigated parameters was founded in newborns with neonatal pneumo pathy. We made the assumption that lymphocyte apoptosis may be part of the reason for the origin of free cell DNA and we propose the possible mechanism of free cell DNA sharing in pathogenesis of derangement adaptation in neonatal period.Key words: free cell DNA, nuclear DNA, intrauterine pneumonia, pneumopathy.

  6. An efficient multi-stage algorithm for full calibration of the hemodynamic model from BOLD signal responses

    KAUST Repository

    Zambri, Brian

    2017-02-22

    We propose a computational strategy that falls into the category of prediction/correction iterative-type approaches, for calibrating the hemodynamic model introduced by Friston et al. (2000). The proposed method is employed to estimate consecutively the values of the biophysiological system parameters and the external stimulus characteristics of the model. Numerical results corresponding to both synthetic and real functional Magnetic Resonance Imaging (fMRI) measurements for a single stimulus as well as for multiple stimuli are reported to highlight the capability of this computational methodology to fully calibrate the considered hemodynamic model. This article is protected by copyright. All rights reserved.

  7. Dataset for: An efficient multi-stage algorithm for full calibration of the hemodynamic model from BOLD signal responses

    KAUST Repository

    Djellouli, Rabia

    2017-01-01

    We propose a computational strategy that falls into the category of prediction/correction iterative-type approaches, for calibrating the hemodynamic model introduced by Friston et al. (2000). The proposed method is employed to estimate consecutively the values of the biophysiological system parameters and the external stimulus characteristics of the model. Numerical results corresponding to both synthetic and real functional Magnetic Resonance Imaging (fMRI) measurements for a single stimulus as well as for multiple stimuli are reported to highlight the capability of this computational methodology to fully calibrate the considered hemodynamic model.

  8. Midodrine and octreotide in treatment of cirrhosis-related hemodynamic complications.

    Science.gov (United States)

    Karwa, Rakhi; Woodis, C Brock

    2009-04-01

    To review studies evaluating the use of midodrine and octreotide in hemodynamic complications of cirrhosis, including ascites and hepatorenal syndrome. Searches of MEDLINE (1966-September 2008) and EMBASE (1974-September 2008) were conducted using the terms midodrine, octreotide, hepatorenal syndrome, ascites, cirrhosis, and paracentesis-induced circulatory dysfunction. Literature review was limited to English-language, human studies. Studies identified from data sources were considered for review. Studies were excluded if primary therapy involved any of the following: transjugular intrahepatic portosystemic shunt procedure, medications other than midodrine or octreotide, or patients included for treatment or prevention of portal hypertension and/or variceal bleeding. Pharmacokinetic/pharmacodynamic studies and studies using retrospective data collection were excluded. Seven studies were included in this review. Midodrine and octreotide in combination or alone have shown conflicting results for systemic and renal hemodynamics and renal function in patients with cirrhosis-related complications. Patients with ascites being treated with midodrine, alone or in combination with octreotide, showed significant changes in systemic hemodynamics, without a correlating change in renal perfusion. Studies comparing the use of midodrine with use of albumin for the prevention of paracentesis-induced circulatory dysfunction (PICD) showed no incidence of PICD in either treatment group. In hepatorenal syndrome, patients using midodrine with octreotide showed significant changes in systemic hemodynamics and improvements in renal perfusion. This regimen's effect on survival is yet to be determined. Available evidence shows inconsistent results for the effectiveness and safety of midodrine and octreotide use in cirrhotic patients. Because of the contradictory results, longer treatment duration and increased number of study participants are necessary to determine the proper use of

  9. The effect of intravenous PACAP38 on cerebral hemodynamics in healthy volunteers

    DEFF Research Database (Denmark)

    Birk, Steffen; Sitarz, John Thomas; Petersen, Kenneth Ahrend

    2007-01-01

    .9+/-22.4% (Phealthy volunteers. The marked increase in heart rate and the reduction in rCBF caused by decreased P(et)CO(2) are important dose-limiting factors to consider in future clinical studies.......PACAP38 is an endogenous peptide located in trigeminal perivascular nerve fibers in the brain. It reduces neuronal loss and infarct size in animal stroke models and has been proposed a candidate substance for human clinical studies of stroke. The effect on systemic hemodynamics and regional...... cerebral blood flow (rCBF) is not well understood. We here present the first study of the effect of PACAP38 on cerebral hemodynamics in humans. PACAP (10 pmol kg(-1) min(-1)) or placebo (0.9% saline) was infused for 20 min into 12 healthy young volunteers in a cross over, double blind study. r...

  10. Hemodynamic instability in the critically ill neonate: An approach to cardiovascular support based on disease pathophysiology.

    Science.gov (United States)

    Giesinger, Regan E; McNamara, Patrick J

    2016-04-01

    Hemodynamic disturbance in the sick neonate is common, highly diverse in underlying pathophysiology and dynamic. Dysregulated systemic and cerebral blood flow is hypothesized to have a negative impact on neurodevelopmental outcome and survival. An understanding of the physiology of the normal neonate, disease pathophysiology, and the properties of vasoactive medications may improve the quality of care and lead to an improvement in survival free from disability. In this review we present a modern approach to cardiovascular therapy in the sick neonate based on a more thoughtful approach to clinical assessment and actual pathophysiology. Targeted neonatal echocardiography offers a more detailed insight into disease processes and offers longitudinal assessment, particularly response to therapeutic intervention. The pathophysiology of common neonatal conditions and the properties of cardiovascular agents are described. In addition, we outline separate treatment algorithms for various hemodynamic disturbances that are tailored to clinical features, disease characteristics and echocardiographic findings. Crown Copyright © 2016. Published by Elsevier Inc. All rights reserved.

  11. Hemodynamics of a Patient-Specific Aneurysm Model with Proper Orthogonal Decomposition

    Science.gov (United States)

    Han, Suyue; Chang, Gary Han; Modarres-Sadeghi, Yahya

    2017-11-01

    Wall shear stress (WSS) and oscillatory shear index (OSI) are two of the most-widely studied hemodynamic quantities in cardiovascular systems that have been shown to have the ability to elicit biological responses of the arterial wall, which could be used to predict the aneurysm development and rupture. In this study, a reduced-order model (ROM) of the hemodynamics of a patient-specific cerebral aneurysm is studied. The snapshot Proper Orthogonal Decomposition (POD) is utilized to construct the reduced-order bases of the flow using a CFD training set with known inflow parameters. It was shown that the area of low WSS and high OSI is correlated to higher POD modes. The resulting ROM can reproduce both WSS and OSI computationally for future parametric studies with significantly less computational cost. Agreement was observed between the WSS and OSI values obtained using direct CFD results and ROM results.

  12. Cell-mediated retraction versus hemodynamic loading - A delicate balance in tissue-engineered heart valves.

    Science.gov (United States)

    van Loosdregt, Inge A E W; Argento, Giulia; Driessen-Mol, Anita; Oomens, Cees W J; Baaijens, Frank P T

    2014-06-27

    Preclinical studies of tissue-engineered heart valves (TEHVs) showed retraction of the heart valve leaflets as major failure of function mechanism. This retraction is caused by both passive and active cell stress and passive matrix stress. Cell-mediated retraction induces leaflet shortening that may be counteracted by the hemodynamic loading of the leaflets during diastole. To get insight into this stress balance, the amount and duration of stress generation in engineered heart valve tissue and the stress imposed by physiological hemodynamic loading are quantified via an experimental and a computational approach, respectively. Stress generation by cells was measured using an earlier described in vitro model system, mimicking the culture process of TEHVs. The stress imposed by the blood pressure during diastole on a valve leaflet was determined using finite element modeling. Results show that for both pulmonary and systemic pressure, the stress imposed on the TEHV leaflets is comparable to the stress generated in the leaflets. As the stresses are of similar magnitude, it is likely that the imposed stress cannot counteract the generated stress, in particular when taking into account that hemodynamic loading is only imposed during diastole. This study provides a rational explanation for the retraction found in preclinical studies of TEHVs and represents an important step towards understanding the retraction process seen in TEHVs by a combined experimental and computational approach. © 2013 Published by Elsevier Ltd.

  13. In vivo measurement of hemodynamic information in stenosed rat blood vessels using X-ray PIV.

    Science.gov (United States)

    Park, Hanwook; Park, Jun Hong; Lee, Sang Joon

    2016-11-28

    Measurements of the hemodynamic information of blood flows, especially wall shear stress (WSS), in animal models with circulatory vascular diseases (CVDs) are important to understand the pathological mechanism of CVDs. In this study, X-ray particle image velocimetry (PIV) with high spatial resolution was applied to obtain velocity field information in stenosed blood vessels with high WSS. 3D clips fabricated with a 3D printer were applied to the abdominal aorta of a rat cadaver to induce artificial stenosis in the real blood vessel of an animal model. The velocity and WSS information of blood flows in the stenosed vessel were obtained and compared at various stenosis severities. In vivo measurement was also conducted by fastening a stenotic clip on a live rat model through surgical intervention to reduce the flow rate to match the limited temporal resolution of the present X-ray PIV system. Further improvement of the temporal resolution of the system might be able to provide in vivo measurements of hemodynamic information from animal disease models under physiological conditions. The present results would be helpful for understanding the relation between hemodynamic characteristics and the pathological mechanism in animal CVD models.

  14. Abnormal hemodynamic response to forepaw stimulation in rat brain after cocaine injection

    Science.gov (United States)

    Chen, Wei; Park, Kicheon; Choi, Jeonghun; Pan, Yingtian; Du, Congwu

    2015-03-01

    Simultaneous measurement of hemodynamics is of great importance to evaluate the brain functional changes induced by brain diseases such as drug addiction. Previously, we developed a multimodal-imaging platform (OFI) which combined laser speckle contrast imaging with multi-wavelength imaging to simultaneously characterize the changes in cerebral blood flow (CBF), oxygenated- and deoxygenated- hemoglobin (HbO and HbR) from animal brain. Recently, we upgraded our OFI system that enables detection of hemodynamic changes in response to forepaw electrical stimulation to study potential brain activity changes elicited by cocaine. The improvement includes 1) high sensitivity to detect the cortical response to single forepaw electrical stimulation; 2) high temporal resolution (i.e., 16Hz/channel) to resolve dynamic variations in drug-delivery study; 3) high spatial resolution to separate the stimulation-evoked hemodynamic changes in vascular compartments from those in tissue. The system was validated by imaging the hemodynamic responses to the forepaw-stimulations in the somatosensory cortex of cocaine-treated rats. The stimulations and acquisitions were conducted every 2min over 40min, i.e., from 10min before (baseline) to 30min after cocaine challenge. Our results show that the HbO response decreased first (at ~4min) followed by the decrease of HbR response (at ~6min) after cocaine, and both did not fully recovered for over 30min. Interestingly, while CBF decreased at 4min, it partially recovered at 18min after cocaine administration. The results indicate the heterogeneity of cocaine's effects on vasculature and tissue metabolism, demonstrating the unique capability of optical imaging for brain functional studies.

  15. [Acute hemodynamic effects of upper airway obstruction in normal dogs].

    Science.gov (United States)

    Lin, C C; Lai, D K; Liu, C C

    1990-09-01

    Eight normal dogs were anesthetized to assess the effects of an upper airway obstruction (UAO) on arterial blood gases (ABG) and hemodynamic (HD) parameters. Each dog was fitted with an arterial line, a Swan-Ganz catheter and an endotracheal tube. The HD parameters including heart rate, systolic blood pressure, central venous pressure (CVP), cardiac index (CI), pulmonary capillary wedge pressure (PCWP), systemic vascular resistance index (SVRI), pulmonary vascular resistance index (PVRI), left ventricle stroke work index (LVSWI) and right ventricle stroke work index (RVSWI), were monitored. The baseline ABG and HD parameters were taken prior to endotracheal tube clamping, and then checked at 0.3, 1.5, 3.0, 4.0 and 5.0 minutes. The clamp was subsequently removed to allow spontaneous breathing, and then another set of measurements were taken at 5, 15 and 30 minutes, respectively. The above procedures were then repeated a second time. The results showed that UAO can produce the following: (1) decreases in the CI, PaO2 and pH; (2) increases in the mean systemic and pulmonary arterial pressure, PCWP, SVRI, PVRI, LVSWI, RVSWI, and PaCO2; (3) significant and acute changes in PaO2 and pH, with the most significant changes occurring within 90 seconds after clamping and then reaching a plateau; and (4) repeated UAO increases in SVRI and PVRI. In conclusion, upper airway obstructions may possibly induce serious ABG and HD changes in humans, as it does in normal dogs.

  16. Effects of thrombin inhibition with melagatran on renal hemodynamics and function and liver integrity during early endotoxemia

    DEFF Research Database (Denmark)

    Nitescu, Nicoletta; Grimberg, Elisabeth; Ricksten, Sven-Erik

    2007-01-01

    Sepsis is associated with an activation of the coagulation system and multiorgan failure. The aim of the study was to examine the effects of selective thrombin inhibition with melagatran on renal hemodynamics and function, and liver integrity, during early endotoxemia. Endotoxemia was induced...

  17. Magnetic resonance imaging signal intensity of temporomandibular joint disk and posterior attachment in patients with internal derangement

    International Nuclear Information System (INIS)

    Jeong, Yeon Hwa; Cho, Bong Hae

    2001-01-01

    To analyze the possible association between magnetic resonance imaging signal intensity of temporomandibular joint disk and posterior attachment, and the type and extent of disk displacement, disk donfiguration, effusion and clinical signs in patients with internal derangement. Magnetic resonance images of the 132 temporomandibular joints of 66 patients with temporomandibular joint displacement were analyzed. The clinical findings were obtained by retrospective review of the patients' records. The type and extent of disk displacement, disk configuration and effusion were evaluated on the proton density MR images. The signal intensity from the anterior band, posterior band and posterior attachment were measured on MR images. The associations between the type and extent of disk displacement, disk configuration, effusion and clinical signs and the MR signal intensity of disk and posterior attachment were statistically analyzed by student's t-test. Of 132 joints, 87 (65.9%) showed anterior disk displacement with reduction (ADR) and 45 (34.1%) showed anterior disk displacement without reduction (ADnR). This signals from posterior attachments were lower in joints with ADnR than those of ADR (p<0.05). The results showed statistically significant (p<0.05) association between the type and extent of disk displacement and disk configuration, and decreased signal intensity of posterior attachment. There were no statistical associations between pain, noise and limited mouth opening, and signal intensity of disk and posterior attachment. The average signal from posterior attachment was lower in joints with ADnR than that of ADR. The type and extent of disk displacement and disk configuration appeared to be correlated with the signal intensity from posterior attachment

  18. Hemodynamic Response Alterations in Sensorimotor Areas as a Function of Barbell Load Levels during Squatting: An fNIRS Study.

    Science.gov (United States)

    Kenville, Rouven; Maudrich, Tom; Carius, Daniel; Ragert, Patrick

    2017-01-01

    Functional near-infrared spectroscopy (fNIRS) serves as a promising tool to examine hemodynamic response alterations in a sports-scientific context. The present study aimed to investigate how brain activity within the human motor system changes its processing in dependency of different barbell load conditions while executing a barbell squat (BS). Additionally, we used different fNIRS probe configurations to identify and subsequently eliminate potential exercise induced systemic confounders such as increases in extracerebral blood flow. Ten healthy, male participants were enrolled in a crossover design. Participants performed a BS task with random barbell load levels (0% 1RM (1 repetition maximum), 20% 1RM and 40% 1RM for a BS) during fNIRS recordings. Initially, we observed global hemodynamic response alterations within and outside the human motor system. However, short distance channel regression of fNIRS data revealed a focalized hemodynamic response alteration within bilateral superior parietal lobe (SPL) for oxygenated hemoglobin (HbO 2 ) and not for deoxygenated hemoglobin (HHb) when comparing different load levels. These findings indicate that the previously observed load/force-brain relationship for simple and isolated movements is also present in complex multi-joint movements such as the BS. Altogether, our results show the feasibility of fNIRS to investigate brain processing in a sports-related context. We suggest for future studies to incorporate short distance channel regression of fNIRS data to reduce the likelihood of false-positive hemodynamic response alterations during complex whole movements.

  19. Echocardiographic Evaluation of Hemodynamics in Neonates and Children

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    Yogen Singh

    2017-09-01

    Full Text Available Hemodynamic instability and inadequate cardiac performance are common in critically ill children. The clinical assessment of hemodynamic status is reliant upon physical examination supported by the clinical signs such as heart rate, blood pressure, capillary refill time, and measurement of the urine output and serum lactate. Unfortunately, all of these parameters are surrogate markers of cardiovascular well-being and they provide limited direct information regarding the adequacy of blood flow and tissue perfusion. A bedside point-of-care echocardiography can provide real-time hemodynamic information by assessing cardiac function, loading conditions (preload and afterload and cardiac output. The echocardiography has the ability to provide longitudinal functional assessment in real time, which makes it an ideal tool for monitoring hemodynamic assessment in neonates and children. It is indispensable in the management of patients with shock, pulmonary hypertension, and patent ductus arteriosus. The echocardiography is the gold standard diagnostic tool to assess hemodynamic stability in patients with pericardial effusion, cardiac tamponade, and cardiac abnormalities such as congenital heart defects or valvar disorders. The information from echocardiography can be used to provide targeted treatment in intensive care settings such as need of fluid resuscitation versus inotropic support, choosing appropriate inotrope or vasopressor, and in providing specific interventions such as selective pulmonary vasodilators in pulmonary hypertension. The physiological information gathered from echocardiography may help in making timely, accurate, and appropriate diagnosis and providing specific treatment in sick patients. There is no surprise that use of bedside point-of-care echocardiography is rapidly gaining interest among neonatologists and intensivists, and it is now being used in clinical decision making for patients with hemodynamic instability. Like any

  20. Increased Hemodynamic Load in Early Embryonic Stages Alters Myofibril and Mitochondrial Organization in the Myocardium

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    Madeline Midgett

    2017-08-01

    Full Text Available Normal blood flow is essential for proper heart formation during embryonic development, as abnormal hemodynamic load (blood pressure and shear stress results in cardiac defects seen in congenital heart disease (CHD. However, the detrimental remodeling processes that relate altered blood flow to cardiac malformation and defects remain unclear. Heart development is a finely orchestrated process with rapid transformations that occur at the tissue, cell, and subcellular levels. Myocardial cells play an essential role in cardiac tissue maturation by aligning in the direction of stretch and increasing the number of contractile units as hemodynamic load increases throughout development. This study elucidates the early effects of altered blood flow on myofibril and mitochondrial configuration in the outflow tract myocardium in vivo. Outflow tract banding was used to increase hemodynamic load in the chicken embryo heart between Hamburger and Hamilton stages 18 and 24 (~24 h during tubular heart stages. 3D focused ion beam scanning electron microscopy analysis determined that increased hemodynamic load induced changes in the developing myocardium, characterized by thicker myofibril bundles that were more disbursed in circumferential orientation, and mitochondria that organized in large clusters around the nucleus. Proteomic mass-spectrometry analysis quantified altered protein composition after banding that is consistent with altered myofibril thin filament assembly and function, and mitochondrial maintenance and organization. Additionally, pathway analysis of the proteomics data identified possible activation of signaling pathways in response to banding, including the renin-angiotensin system (RAS. Imaging and proteomic data combined indicate that myofibril and mitochondrial arrangement in early embryonic stages is a critical developmental process that when disturbed by altered blood flow may contribute to cardiac malformation and defects.

  1. Change of central hemodynamics of qualified athletes for testing the use of controlled breathing and evaluation

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    A.P. Romanchuk

    2013-11-01

    Full Text Available Using spiroarteriocardiorhythmography surveyed 174 qualified athletes (121 male and 53 female. The examination consisted of three consecutive two-minute registrations - spontaneous, controlled breathing 6 and 15 breaths per minute. Found that the hemodynamic change substantially when the respiratory tests in the first place, cardiac output, cardiac index, total peripheral vascular resistance and specific peripheral vascular resistance. To develop criteria for evaluation of hemodynamic changes carried percentile variance analysis of all indicators in the performance tests. Testing of the evaluation criteria for different types of hemodynamics in athletes allowed to establish that eukinetic type characteristic is the reduction in heart rate and pulse blood pressure under test with controlled breathing 6 times per minute for hypokinetic – pronounced increase in systolic blood pressure and pulse blood pressure during the breath tests 6 and 15 times per minute for hyperkinetic – reducing end-diastolic volume, end-systolic volume, stroke volume, in vivo performance of both tests and an increase in systemic vascular resistance during test 15 breaths per minute.

  2. Metabolic and hemodynamic effects of saline infusion to maintain volemia on temporary abdominal aortic occlusion

    Directory of Open Access Journals (Sweden)

    Fábio Ferreira Amorim

    2002-10-01

    Full Text Available OBJECTIVE: To analyze hemodynamic and metabolic effects of saline solution infusion in the maintenance of blood volume in ischemia-reperfusion syndrome during temporary abdominal aortic occlusion in dogs. METHODS: We studied 20 dogs divided into 2 groups: the ischemia-reperfusion group (IRG, n=10 and the ischemia-reperfusion group with saline solution infusion aiming at maintaining mean pulmonary arterial wedge pressure between 10 and 20 mmHg (IRG-SS, n=10. All animals were anesthetized with sodium thiopental and maintained on spontaneous ventilation. Occlusion of the supraceliac aorta was obtained with inflation of a Fogarty catheter inserted through the femoral artery. After 60 minutes of ischemia, the balloon was deflated, and the animals were observed for another 60 minutes of reperfusion. RESULTS: IRG-SS dogs did not have hemodynamic instability after aortic unclamping, and the mean systemic blood pressure and heart rate were maintained. However, acidosis worsened, which was documented by a greater reduction of arterial pH that occurred especially due to the absence of a respiratory response to metabolic acidosis that was greater with the adoption of this procedure. CONCLUSION: Saline solution infusion to maintain blood volume avoided hemodynamic instability after aortic unclamping. This procedure, however, caused worsening in metabolic acidosis in this experimental model.

  3. Hemodynamic Based Coronary Artery Aneurysm Thrombosis Risk Stratification in Kawasaki Disease Patients

    Science.gov (United States)

    Grande Gutierrez, Noelia; Mathew, M.; McCrindle, B.; Kahn, A.; Burns, J.; Marsden, A.

    2017-11-01

    Coronary artery aneurysms (CAA) as a result of Kawasaki Disease (KD) put patients at risk for thrombosis and myocardial infarction. Current AHA guidelines recommend CAA diameter >8 mm or Z-score >10 as the criterion for initiating systemic anticoagulation. Our hypothesis is that hemodynamic data derived from computational blood flow simulations is a better predictor of thrombosis than aneurysm diameter alone. Patient-specific coronary models were constructed from CMRI for a cohort of 10 KD patients (5 confirmed thrombosis cases) and simulations with fluid structure interaction were performed using the stabilized finite element Navier-Stokes solver available in SimVascular. We used a closed-loop lumped parameter network (LPN) to model the heart and vascular boundary conditions coupled numerically to the flow solver. An automated parameter estimation method was used to match LPN values to clinical data for each patient. Hemodynamic data analysis resulted in low correlation between Wall Shear Stress (WSS)/ Particle Residence Time (PRT) and CAA diameter but demonstrates the positive correlation between hemodynamics and adverse patient outcomes. Our results suggest that quantifying WSS and PRT should enable identification of regions at higher risk of thrombosis. We propose a quantitative method to non-invasively assess the abnormal flow in CAA following KD that could potentially improve clinical decision-making regarding anticoagulation therapy.

  4. Hybrid diffuse optical techniques for continuous hemodynamic measurement in gastrocnemius during plantar flexion exercise

    Science.gov (United States)

    Henry, Brad; Zhao, Mingjun; Shang, Yu; Uhl, Timothy; Thomas, D. Travis; Xenos, Eleftherios S.; Saha, Sibu P.; Yu, Guoqiang

    2015-12-01

    Occlusion calibrations and gating techniques have been recently applied by our laboratory for continuous and absolute diffuse optical measurements of forearm muscle hemodynamics during handgrip exercises. The translation of these techniques from the forearm to the lower limb is the goal of this study as various diseases preferentially affect muscles in the lower extremity. This study adapted a hybrid near-infrared spectroscopy and diffuse correlation spectroscopy system with a gating algorithm to continuously quantify hemodynamic responses of medial gastrocnemius during plantar flexion exercises in 10 healthy subjects. The outcomes from optical measurement include oxy-, deoxy-, and total hemoglobin concentrations, blood oxygen saturation, and relative changes in blood flow (rBF) and oxygen consumption rate (rV˙O2). We calibrated rBF and rV˙O2 profiles with absolute baseline values of BF and V˙O2 obtained by venous and arterial occlusions, respectively. Results from this investigation were comparable to values from similar studies. Additionally, significant correlation was observed between resting local muscle BF measured by the optical technique and whole limb BF measured concurrently by a strain gauge venous plethysmography. The extensive hemodynamic and metabolic profiles during exercise will allow for future comparison studies to investigate the diagnostic value of hybrid technologies in muscles affected by disease.

  5. Protective Effects of Methylsulfonylmethane on Hemodynamics and Oxidative Stress in Monocrotaline-Induced Pulmonary Hypertensive Rats

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    Sadollah Mohammadi

    2012-01-01

    Full Text Available Methylsulfonylmethane (MSM is naturally occurring organic sulfur that is known as a potent antioxidant/anti-inflammatory compound. The aim of this study was to investigate the effect of MSM on hemodynamics functions and oxidative stress in rats with monocrotaline- (MCT- induced pulmonary arterial hypertension (PAH. Wistar rats were randomly assigned to 38-days treatment. MSM was administered to rats at 100, 200, and 400 mg/kg/day doses 10 days before a single dose of 60 mg/kg, IP, MCT. Hemodynamics of ventricles were determined by Powerlab AD instrument. Blood samples were obtained to evaluate changes in the antioxidative system including activities of catalase (CAT, superoxide dismutase (SOD, glutathione peroxidase (GPx, and the level of reduced glutathione (GSH and malondialdehyde (MDA. Improvements in cardiopulmonary hemodynamics were observed in the MSM-treated pulmonary arterial hypertensive rats, with a significant reduction in right ventricular systolic pressure (RSVP and an increase in the mean arterial pressure (MAP. The values of CAT, SOD, GSH-px activities, and GSH were significantly lower in MCT-induced PAH (P<0.01, but they were recovered to control levels of MSM-treated groups. Our present results suggest that long-term administration of the MSM attenuates MCT-induced PAH in rats through modulation of oxidative stress and antioxidant defense.

  6. Application of near-infrared spectroscopy to measurement of hemodynamic signals accompanying stimulated saliva secretion.

    Science.gov (United States)

    Sato, Hiroki; Obata, Akiko N; Moda, Ichiro; Ozaki, Kazutaka; Yasuhara, Takaomi; Yamamoto, Yukari; Kiguchi, Masashi; Maki, Atsushi; Kubota, Kisou; Koizumi, Hideaki

    2011-04-01

    We aim to test the feasibility of using near-infrared spectroscopy (NIRS) for indirect measurement of human saliva secretion in response to taste stimuli for potential application to organoleptic testing. We use an NIRS system to measure extracranial hemodynamics (Hb-signals around the temples) of healthy participants when taste stimuli are taken in their mouths. First, the Hb-signals and volume of expelled saliva (stimulated by distilled-water or sucrose-solution intake) are simultaneously measured and large Hb-signal changes in response to the taste stimuli (Hb-responses) are found. Statistical analysis show that both the Hb response and saliva volume are larger for the sucrose solution than for the distilled water with a significant correlation between them (r = 0.81). The effects of swallowing on the Hb-signals are investigated. Similar Hb responses, differing from the sucrose solution and distilled water, are obtained even though the participants swallow the mouth contents. Finally, functional magnetic resonance imaging is used to identify possible sources of the Hb signals corresponding to salivation. Statistical analysis indicates similar responses in the extracranial regions, mainly around the middle meningeal artery. In conclusion, the identified correlation between extracranial hemodynamics and the saliva volume suggests that NIRS is applicable to the measurement of hemodynamic signals accompanying stimulated saliva secretion.

  7. Oxytocin modulates hemodynamic responses to monetary incentives in humans.

    Science.gov (United States)

    Mickey, Brian J; Heffernan, Joseph; Heisel, Curtis; Peciña, Marta; Hsu, David T; Zubieta, Jon-Kar; Love, Tiffany M

    2016-12-01

    Oxytocin is a neuropeptide widely recognized for its role in regulating social and reproductive behavior. Increasing evidence from animal models suggests that oxytocin also modulates reward circuitry in non-social contexts, but evidence in humans is lacking. We examined the effects of oxytocin administration on reward circuit function in 18 healthy men as they performed a monetary incentive task. The blood oxygenation level-dependent (BOLD) signal was measured using functional magnetic resonance imaging in the context of a randomized, double-blind, placebo-controlled, crossover trial of intranasal oxytocin. We found that oxytocin increases the BOLD signal in the midbrain (substantia nigra and ventral tegmental area) during the late phase of the hemodynamic response to incentive stimuli. Oxytocin's effects on midbrain responses correlated positively with its effects on positive emotional state. We did not detect an effect of oxytocin on responses in the nucleus accumbens. Whole-brain analyses revealed that oxytocin attenuated medial prefrontal cortical deactivation specifically during anticipation of loss. Our findings demonstrate that intranasal administration of oxytocin modulates human midbrain and medial prefrontal function during motivated behavior. These findings suggest that endogenous oxytocin is a neurochemical mediator of reward behaviors in humans-even in a non-social context-and that the oxytocinergic system is a potential target of pharmacotherapy for psychiatric disorders that involve dysfunction of reward circuitry.

  8. Dietary melatonin alters uterine artery hemodynamics in pregnant Holstein heifers.

    Science.gov (United States)

    Brockus, K E; Hart, C G; Gilfeather, C L; Fleming, B O; Lemley, C O

    2016-04-01

    The objective was to examine uterine artery hemodynamics and maternal serum profiles in pregnant heifers supplemented with dietary melatonin (MEL) or no supplementation (CON). In addition, melatonin receptor-mediated responses in steroid metabolism were examined using a bovine endometrial epithelial culture system. Twenty singleton pregnant Holstein heifers were supplemented with 20 mg of melatonin (n = 10) or no melatonin supplementation (control; n = 10) from days 190 to 262 of gestation. Maternal measurements were recorded on days 180 (baseline), 210, 240, and 262 of gestation. Total uterine blood flow was increased by 25% in the MEL-treated heifers compared with the CON. Concentrations of progesterone were decreased in MEL vs CON heifers. Total serum antioxidant capacity was increased by 43% in MEL-treated heifers when compared with CON. Activity of cytochrome P450 1A, 2C, and superoxide dismutase was increased in bovine endometrial epithelial cells treated with melatonin, whereas the melatonin receptor antagonist, luzindole, negated the increase in cytochrome P450 2C activity. Moreover, estradiol or progesterone treatment altered bovine uterine melatonin receptor expression, which could potentiate the melatonin-mediated responses during late gestation. The observed increase in total uterine blood flow during melatonin supplementation could be related to its antioxidant properties. Compromised pregnancies are typically accompanied by increased oxidative stress; therefore, melatonin could serve as a therapeutic supplementation strategy. This could lead to further fetal programming implications in conjunction with offspring growth and development postnatally. Copyright © 2016 Elsevier Inc. All rights reserved.

  9. Oxytocin modulates hemodynamic responses to monetary incentives in humans

    Science.gov (United States)

    Mickey, Brian J.; Heffernan, Joseph; Heisel, Curtis; Peciña, Marta; Hsu, David T.; Zubieta, Jon-Kar; Love, Tiffany M.

    2016-01-01

    Oxytocin is a neuropeptide widely recognized for its role in regulating social and reproductive behavior. Increasing evidence from animal models suggests that oxytocin also modulates reward circuitry in non-social contexts, but evidence in humans is lacking. Here we examined the effects of oxytocin administration on reward circuit function in 18 healthy men as they performed a monetary incentive task. The blood oxygenation level dependent (BOLD) signal was measured using functional magnetic resonance imaging in the context of a randomized, double-blind, placebo-controlled, crossover trial of intranasal oxytocin. We found that oxytocin increases the BOLD signal in the midbrain (substantia nigra and ventral tegmental area) during the late phase of the hemodynamic response to incentive stimuli. Oxytocin’s effects on midbrain responses correlated positively with its effects on positive emotional state. We did not detect an effect of oxytocin on responses in the nucleus accumbens. Whole-brain analyses revealed that oxytocin attenuated medial prefrontal cortical deactivation specifically during anticipation of loss. Our findings demonstrate that intranasal administration of oxytocin modulates human midbrain and medial prefrontal function during motivated behavior. These findings suggest that endogenous oxytocin is a neurochemical mediator of reward behaviors in humans – even in a non-social context – and that the oxytocinergic system is a potential target of pharmacotherapy for psychiatric disorders that involve dysfunction of reward circuitry. PMID:27614896

  10. Changes in hemodynamic parameters and cerebral saturation during supraventricular tachycardia.

    Science.gov (United States)

    Hershenson, Jared A; Ro, Pamela S; Miao, Yongjie; Tobias, Joseph D; Olshove, Vincent; Naguib, Aymen N

    2012-02-01

    Induced supraventricular tachycardia (SVT) during electrophysiology studies (EPS) can be associated with hemodynamic changes. Traditionally, invasive arterial blood pressure has been used for continuous monitoring of these changes. This prospective study evaluated the efficacy of near-infrared spectroscopy (NIRS) monitoring during SVT. The use of NIRS has expanded with evidence of its accuracy and benefit in detecting cerebral hypoperfusion. This study aimed first to determine the hemodynamic changes associated with electrophysiology testing for SVT and second to determine whether the hemodynamic changes are associated with similar changes in the cerebral saturation as determined by NIRS. The study enrolled 30 patients 5-20 years of age with a history of SVT who underwent an EPS. The demographic data included age, gender, weight, height, and type of SVT. Hemodynamic data (invasive blood pressure and heart rate), NIRS, bispectral index (BIS), end-tidal carbon dioxide, and pulse oximetry were collected before and during three episodes of induced SVT. The linear correlation coefficient (r) was measured to calculate the relationship of the changes in systolic blood pressure (SBP), diastolic blood pressure (DBP), and mean arterial pressure (MAP) to the changes in NIRS values during the SVT episodes. Data from 22 patients were collected. The induction of SVT was associated mainly with a change in SBP and a less prominent change in DBP and MAP from baseline. The changes in hemodynamic status were associated with minimal changes in cerebral saturations, as evidenced by an average absolute change in NIRS of SVT during electrophysiology testing is associated with hemodynamic changes, mainly in SBP. In this study, these hemodynamic changes resulted in a minimal decrease in cerebral perfusion, as evidenced by minimal changes in the cerebral saturation measured by NIRS (0.7% from baseline). Although the changes in the cerebral saturation were minimal, these changes were

  11. Postoperative hemodynamics after cardiopulmonary bypass in survived newborn piglets.

    Science.gov (United States)

    Tirilomis, Theodor; Nolte, Lars; Liakopoulos, Oliver J; Ballat, Carola; Steinke, Katja; Bensch, Marc; Schoendube, Friedrich A

    2009-01-01

    Cardiac function and hemodynamics are frequently decreased during the first hours after heart surgery, resulting in inotropic support for treatment and prevention of further hemodynamic deterioration. The aim of this study was analysis of hemodynamics of neonatal piglets who survived early postoperative course after cardiopulmonary bypass (CPB) and cardioplegic arrest without the use of inotropic drugs. Newborn piglets (younger than 7 days) were placed on mild hypothermic CPB (32 degrees C) for 180 minutes, including 90 minutes of cardioplegic arrest. Hemodynamics were examined after termination of CPB and none of the animals received any inotropic support. After 6 hours, survived animals were euthanized (CPB group, n=4). For control, neonatal piglets were examined for the same time interval after surgery without CPB (control group, n=3). Systolic left-ventricular pressure increased after CPB, mean arterial blood pressure and amplitude of left ventricular wall thickness decreased. Compared with control group, systolic left-ventricular pressure in CPB group was higher (p<0.05). Present data demonstrated hemodynamic depression after cardiac procedures in survived neonatal animals. Although the effects may not be solely attributed to CPB and myocardial ischemia effects may be potentiate by CPB.

  12. Static and Functional Hemodynamic Profiles of Women with Abnormal Uterine Artery Doppler at 22-24 Weeks of Gestation.

    Science.gov (United States)

    Vårtun, Åse; Flo, Kari; Widnes, Christian; Acharya, Ganesh

    2016-01-01

    To compare cardiac function, systemic hemodynamics and preload reserve of women with increased (cases) and normal (controls) uterine artery (UtA) pulsatility index (PI) at 22-24 weeks of gestation. A prospective cross-sectional study of 620 pregnant women. UtA blood flow velocities were measured using Doppler ultrasonography, and PI was calculated. Mean UtA PI ≥ 1.16 (90th percentile) was considered abnormal. Maternal hemodynamics was investigated at baseline and during passive leg raising (PLR) using impedance cardiography (ICG). Preload reserve was defined as percent increase in stroke volume (SV) 90 seconds after passive leg raising compared to baseline. Mean UtA PI was 1.49 among cases (n = 63) and 0.76 among controls (n = 557) (p UtA PI had higher blood pressure and systemic vascular resistance, but similar functional hemodynamic profile at 22-24 weeks compared to controls. Further studies are needed to clarify whether functional hemodynamic assessment using ICG can be useful in predicting pregnancy complications.

  13. The optimal hemodynamics management of post-cardiac arrest shock.

    Science.gov (United States)

    Pellis, Tommaso; Sanfilippo, Filippo; Ristagno, Giuseppe

    2015-12-01

    Patients resuscitated from cardiac arrest develop a pathophysiological state named "post-cardiac arrest syndrome." Post-resuscitation myocardial dysfunction is a common feature of this syndrome, and many patients eventually die from cardiovascular failure. Cardiogenic shock accounts for most deaths in the first 3 days, when post-resuscitation myocardial dysfunction peaks. Thus, identification and treatment of cardiovascular failure is one of the key therapeutic goals during hospitalization of post-cardiac arrest patients. Patients with hemodynamic instability may require advanced cardiac output monitoring. Inotropes and vasopressors should be considered if hemodynamic goals are not achieved despite optimized preload. If these measures fail to restore adequate organ perfusion, a mechanical circulatory assistance device may be considered. Adequate organ perfusion should be ensured in the absence of definitive data on the optimal target pressure goals. Hemodynamic goals should also take into account targeted temperature management and its effect on the cardiovascular function. Copyright © 2015 Elsevier Ltd. All rights reserved.

  14. Ocular hemodynamics and glaucoma: the role of mathematical modeling.

    Science.gov (United States)

    Harris, Alon; Guidoboni, Giovanna; Arciero, Julia C; Amireskandari, Annahita; Tobe, Leslie A; Siesky, Brent A

    2013-01-01

    To discuss the role of mathematical modeling in studying ocular hemodynamics, with a focus on glaucoma. We reviewed recent literature on glaucoma, ocular blood flow, autoregulation, the optic nerve head, and the use of mathematical modeling in ocular circulation. Many studies suggest that alterations in ocular hemodynamics play a significant role in the development, progression, and incidence of glaucoma. Although there is currently a limited number of studies involving mathematical modeling of ocular blood flow, regulation, and diseases (such as glaucoma), preliminary modeling work shows the potential of mathematical models to elucidate the mechanisms that contribute most significantly to glaucoma progression. Mathematical modeling is a useful tool when used synergistically with clinical and laboratory data in the study of ocular blood flow and glaucoma. The development of models to investigate the relationship between ocular hemodynamic alterations and glaucoma progression will provide a unique and useful method for studying the pathophysiology of glaucoma.

  15. Hemodynamic effects of a novel pharmacologic stress agent, Higemine

    International Nuclear Information System (INIS)

    Zhang, X.L.; Liu, X.J.; Tao, Z.H.; Shi, R.F.

    2002-01-01

    Objective: Higenamine (dl-demethylcodaurine) (HG), which was isolated from aconitum japonicum. This study was to evaluate the hemodynamic effects of HG in animal study. Methods: We compared the hemodynamic effects of HG (0.5-4μg/min/kg) with Dobutamine (Dob) (5-30μg/min/kg) in 6 dogs: heart rate (HR), blood pressure (BP), coronary blood flow (CBF), myocardial oxygen consumption (MOC) were measured. Tolerability and safety of HG (1-500μg/mg/min) were evaluated in 8 dogs. Results: Comparison of hemodynamic effects between Dob an HG was presented. SBP: systolic blood pressure; DP: diastolic blood pressure; P<0.01; P<0.05. Diastolic BP slightly decreased, but systolic BP did not change significantly during HG infusion. There was no significant ECG abnormalities and side effects during HG infusion. Conclusion: HG might be a safe and useful pharmacologic stress agent, especially for patients with severe hypertension

  16. Hemodynamics of portal blood flow shown by CT portography: work in progress

    International Nuclear Information System (INIS)

    Reinig, J.W.; Sanchez, F.W.; Vujic, I.

    1985-01-01

    Computed tomography and arterial portography were combined in 12 patients for studies of the anatomy and hemodynamics of the portal venous system. This technique was found to be more sensitive than conventional venous-phase angiograms of the superior mesenteric and splenic arteries for evaluation of the anatomy of the portal venous system and extent of thrombosis in patients with cavernous transformation and also facilitated recognition of subtle evidence of hepatofugal flow and portosystemic shunts. CT portography can be employed when conventional angiograms fail to show the portal vein adequately

  17. Hemodynamics of portal blood flow shown by CT portography: work in progress

    Energy Technology Data Exchange (ETDEWEB)

    Reinig, J.W.; Sanchez, F.W.; Vujic, I.

    1985-02-01

    Computed tomography and arterial portography were combined in 12 patients for studies of the anatomy and hemodynamics of the portal venous system. This technique was found to be more sensitive than conventional venous-phase angiograms of the superior mesenteric and splenic arteries for evaluation of the anatomy of the portal venous system and extent of thrombosis in patients with cavernous transformation and also facilitated recognition of subtle evidence of hepatofugal flow and portosystemic shunts. CT portography can be employed when conventional angiograms fail to show the portal vein adequately.

  18. A neuro-fuzzy approach for predicting hemodynamic responses during anesthesia.

    Science.gov (United States)

    Nunes, Catarina S; Amorim, Pedro

    2008-01-01

    The effect of drugs' interaction on the hemo-dynamic variables is of great importance when considering patient's safety and stability. It is also important for control infusion systems during anesthesia. In this article, an adaptive-network fuzzy inference system is used to model the effect of two drugs (propofol and remifentanil) on the mean arterial pressure and heart rate. The clinical data of 45 patients is used to train and test the model. The use of subtractive clustering improved the model performance on the testing data set. The fuzzy model is able to capture the synergistic interaction between the two drugs, but other influences were detected.

  19. Hemodynamic characteristics of hyperplastic remodeling lesions in cerebral aneurysms.

    Directory of Open Access Journals (Sweden)

    Kazuhiro Furukawa

    Full Text Available Hyperplastic remodeling (HR lesions are sometimes found on cerebral aneurysm walls. Atherosclerosis is the results of HR, which may cause an adverse effect on surgical treatment for cerebral aneurysms. Previous studies have demonstrated that atherosclerotic changes had a correlation with certain hemodynamic characteristics. Therefore, we investigated local hemodynamic characteristics of HR lesions of cerebral aneurysms using computational fluid dynamics (CFD.Twenty-four cerebral aneurysms were investigated using CFD and intraoperative video recordings. HR lesions and red walls were confirmed on the intraoperative images, and the qualification points were determined on the center of the HR lesions and the red walls. The qualification points were set on the virtual operative images for evaluation of wall shear stress (WSS, normalized WSS (NWSS, oscillatory shear index (OSI, relative residence time (RRT, and aneurysm formation indicator (AFI. These hemodynamic parameters at the qualification points were compared between HR lesions and red walls.HR lesions had lower NWSS, lower AFI, higher OSI and prolonged RRT compared with red walls. From analysis of the receiver-operating characteristic curve for hemodynamic parameters, OSI was the most optimal hemodynamic parameter to predict HR lesions (area under the curve, 0.745; 95% confidence interval, 0.603-0.887; cutoff value, 0.00917; sensitivity, 0.643; specificity, 0.893; P<0.01. With multivariate logistic regression analyses using stepwise method, NWSS was significantly associated with the HR lesions.Although low NWSS was independently associated with HR lesions, OSI is the most valuable hemodynamic parameter to distinguish HR lesions from red walls.

  20. Frequency of non alcoholic fatty liver disease (NAFLD) and its biochemical derangements in Type-2 diabetic patients

    International Nuclear Information System (INIS)

    Taseer, I.H.; Hussain, L.; Safdar, S.; Mirbahar, A.M.; Ahmad, I.

    2010-01-01

    Objective: To see the frequency of non-alcoholic fatty liver disease in Type-2 diabetic patients and to see iochemical derangements in NAFLD patients. Methodology: It is a cross-sectional study, conducted at Diabetic Research Centre and outpatient department Nishtar Hospital and PMRC Research Centre Nishtar Medical College, Multan. One hundred patients of either sex having type 2 diabetes mellitus attending diabetic out-patient department Nishtar Hospital Multan were included in the study. A pre-designed study proforma was filled with relevant investigations and clinical assessments were carried out in all cases. All the patients underwent abdominal ultrasonography. Data were entered in SPSS-11 and analyzed. Results: Out of one hundred patients, 51 (51%) were female and 49 (49%) were male. Mean age of the patients was 47.93 +- 8.57 years. Fifty one (51%) of the diabetic patients had fatty liver. Out of these 32 (62.75%) were female and 19 (37.25%) were male. Fatigue was present in 49 (53.26%), generalized weakness in 48 (52.18%), heaviness right upper abdomen in 22 (64.70%) and pain right upper abdomen in 20 (58.82%) of fatty liver patients. Corresponding figure in Non Fatty Liver Patients were 43 (46.74%), 44 (47.82%), 12 (35.30%) and 14(41.18%), respectively. Itching was noted in 19 (44.18%) patients of fatty liver while it was 24(55.82%) in non-fatty liver patients. Serum triglyceride level more than 160 mg/dl in 47 (92.15%) patients of fatty liver while serum cholesterol level more than 200 mg/dl was seen in 24(47.05%). Aspartate amino transferase (AST) more than 35 u/l was noted in seven (13.72%), alanine amino-transferase (ALT) more than 40u/l was noted in 6(11.76%) fatty liver patients while serum albumin and serum bilirubin were within normal range in all fatty liver and non-fatty liver patients. Conclusion: Nonalcoholic fatty liver disease (NAFLD) is more commonly seen in Type-2 diabetic patients. Serum triglyceride and serum cholesterol are significantly

  1. Maternal hemodynamics: a method to classify hypertensive disorders of pregnancy.

    Science.gov (United States)

    Ferrazzi, Enrico; Stampalija, Tamara; Monasta, Lorenzo; Di Martino, Daniela; Vonck, Sharona; Gyselaers, Wilfried

    2018-01-01

    The classification of hypertensive disorders of pregnancy is based on the time at the onset of hypertension, proteinuria, and other associated complications. Maternal hemodynamic interrogation in hypertensive disorders of pregnancy considers not only the peripheral blood pressure but also the entire cardiovascular system, and it might help to classify the different clinical phenotypes of this syndrome. This study aimed to examine cardiovascular parameters in a cohort of patients affected by hypertensive disorders of pregnancy according to the clinical phenotypes that prioritize fetoplacental characteristics and not the time at onset of hypertensive disorders of pregnancy. At the fetal-maternal medicine unit of Ziekenhuis Oost-Limburg (Genk, Belgium), maternal cardiovascular parameters were obtained through impedance cardiography using a noninvasive continuous cardiac output monitor with the patients placed in a standing position. The patients were classified as pregnant women with hypertensive disorders of pregnancy who delivered appropriate- and small-for-gestational-age fetuses. Normotensive pregnant women with an appropriate-for-gestational-age fetus at delivery were enrolled as the control group. The possible impact of obesity (body mass index ≥30 kg/m 2 ) on maternal hemodynamics was reassessed in the same groups. Maternal age, parity, body mass index, and blood pressure were not significantly different between the hypertensive disorders of pregnancy/appropriate-for-gestational-age and hypertensive disorders of pregnancy/small-for-gestational-age groups. The mean uterine artery pulsatility index was significantly higher in the hypertensive disorders of pregnancy/small-for-gestational-age group. The cardiac output and cardiac index were significantly lower in the hypertensive disorders of pregnancy/small-for-gestational-age group (cardiac output 6.5 L/min, cardiac index 3.6) than in the hypertensive disorders of pregnancy/appropriate-for-gestational-age group

  2. Comprehensive cognitive and cerebral hemodynamic evaluation after cranioplasty.

    Science.gov (United States)

    Coelho, Fernanda; Oliveira, Arthur Maynart; Paiva, Wellingson Silva; Freire, Fabio Rios; Calado, Vanessa Tome; Amorim, Robson Luis; Neville, Iuri Santana; de Andrade, Almir Ferreira; Bor-Seng-Shu, Edson; Anghinah, Renato; Teixeira, Manoel Jacobsen

    2014-01-01

    Decompressive craniectomy is an established procedure to lower intracranial pressure and can save patients' lives. However, this procedure is associated with delayed cognitive decline and cerebral hemodynamics complications. Studies show the benefits of cranioplasty beyond cosmetic aspects, including brain protection, and functional and cerebrovascular aspects, but a detailed description of the concrete changes following this procedure are lacking. In this paper, the authors report a patient with trephine syndrome who underwent cranioplasty; comprehensive cognitive and cerebral hemodynamic evaluations were performed prior to and following the cranioplasty. The discussion was based on a critical literature review.

  3. Echocardiography and ultrasound dopplerography assessment of central and peripheral hemodynamics in children with septic shock

    Directory of Open Access Journals (Sweden)

    V.V. Yevtushenko

    2017-08-01

    Full Text Available Background. The severe course of sepsis is usually associated with the development of septic shock and multiple organ failure. For effective treatment, it is recommended to perform instrumental monitoring of preload, contractile capacity of the heart and tissue perfusion. We aimed to evaluate changes in central and peripheral hemodynamics by echocardiography and Doppler ultrasound in children with septic shock. Materials and methods. A retrospective study of cases of septic shock in children aged 0 to 18 years who underwent treatment in the intensive care unit was conducted. Patients were monitored for central and peripheral hemodynamics by echocardiography and Doppler ultrasound. The initial study of hemodynamic parameters was carried out over the first 3 hours after hospitalization. The second study was carried out in 24–36 hours after the hospitalization. The third study was conducted in the period of convalescence within 24–48 hours after the withdrawal of sympathomimetic drugs. Results. Thirty-four cases of sepsis associated with septic shock were investigated. In 24 (70.6 % patients, the etiological factor was meningococcus, in 1 (2.9 % staphylococcus, and in 9 (26.5 % no aetiology was established. In 6 children from the study group fatal outcome occurred. Values of mean blood pressure, ejection fraction, peripheral resistance were relatively lower in the acute shock period, and increased after stabilization of hemodynamics. Evaluation of peripheral blood circulation at admission showed decreased diastolic velocity in abdominal aorta and upper mesenteric artery and systolic velocity in posterior tibial artery. The results of initial investigation demonstrated that 44.1 % patients had increased cardiac output along with decreased systemic vascular resistance (‘warm shock’, and just 8.8 % had features of ‘cold shock’ (decreased cardiac output and increased vascular resistance. The fatal course of the disease was associated with

  4. The effect of fluid viscosity on the hemodynamic energy changes during operation of the pulsatile ventricular assist device.

    Science.gov (United States)

    Ahn, Chi Bum; Son, Kuk Hui; Lee, Jung Joo; Choi, Jaesoon; Song, Seung Joon; Jung, Jae Seung; Lee, Sung Ho; Son, Ho Sung; Sun, Kyung

    2011-11-01

    Blood viscosity during operation of ventricular assist device (VAD) can be changed by various conditions such as anemia. It is known generally that the blood viscosity can affect vascular resistance and lead to change of blood flow. In this study, the effect of fluid viscosity variation on hemodynamic energy was evaluated with a pulsatile blood pump in a mock system. Six solutions were used for experiments, which were composed of water and glycerin and had different viscosities of 2, 2.5, 3, 3.5, 4, and 4.5 cP. The hemodynamic energy at the outlet cannula was measured. Experimental results showed that mean pressure was increased in accordance with the viscosity increase. When the viscosity increased, the mean pressure was also increased. However, the flow was decreased according to the viscosity increase. Energy equivalent pressure value was increased according to the viscosity-induced pressure rise; however, surplus hemodynamic energy value did not show any apparent changing trend. The hemodynamic energy made by the pulsatile VAD was affected by the viscosity of the circulating fluid. © 2011, Copyright the Authors. Artificial Organs © 2011, International Center for Artificial Organs and Transplantation and Wiley Periodicals, Inc.

  5. Hemodynamics-based treatment of varices: A therapeutic concept counteracting the intrinsic tendency of varicose veins to recur.

    Science.gov (United States)

    Recek, Cestmir

    2016-12-01

    Varicose vein disease is characterized by tenacious tendency to recur. Measures recommended to prevent recurrences (flush ligation at the saphenofemoral junction, removal of incompetent great saphenous vein in the thigh, and insertion of mechanical barriers in the fossa ovalis) did not succeed in preventing recurrence. Reflux recurrence is triggered by the hemodynamic phenomenon called hemodynamic paradox. Abolition of saphenous reflux removes the hemodynamic disturbance of any degree of severity but at the same time it releases the pathological process leading to recurrent reflux. This process is induced by drainage of venous blood from incompetent superficial thigh veins into deep lower leg veins during calf pump activity, which evokes the development of ambulatory pressure gradient between the femoral vein and incompetent segments of the saphenous system in the thigh. The pressure gradient sets off biophysical and biochemical events inducing recurrent reflux. The designed therapeutic strategy consists of reliable abolition of saphenous reflux and of hindering the pathological drainage of venous blood at the knee level in order to preclude development of the hemodynamic preconditions for reflux recurrence. In this way, the dividing line of the ambulatory pressure gradient would be kept below the knee, as is the case with healthy people.

  6. Comparison of hemodynamic responses to static and dynamic exercise.

    Science.gov (United States)

    Bezucha, G R; Lenser, M C; Hanson, P G; Nagle, F J

    1982-12-01

    Eight healthy male adults (25-34 yr) were studied to compare hemodynamic responses to static exercise (30% MVC in leg extension), static-dynamic exercise (one-arm cranking, 66 and 79% VO2 max-arm), and dynamic exercise (two-leg cycling, 58 and 82% VOmax-legs). Leg extension (LE) strength was measured by a spring scale. Cranking and cycling were performed on a Quinton bicycle ergometer. VO2 was measured using an automated open-circuit system. Heart rate (HR) was monitored from a CM-5 ECG lead, and arterial pressure (Pa) was measured from an indwelling brachial artery catheter. Cardiac output (Q) was measured using a CO2-rebreathing procedure. Total peripheral resistance (TPR) was calculated using the mean arterial pressure (Pa) as the systemic pressure gradient. In 30% LE, a significant (P less than 0.05) Pa increase occurred (pressor response) mediated primarily by an increase in Q. One-arm cranking and two-leg cycling at similar relative VO2 demands resulted in nearly identical increases in Pa due to different contributions of Q and TPR. Q and the arteriovenous O2 difference varied as a function of VO2 regardless of the mode of exercise (static or dynamic). On the other hand, the HR response, which accounted for increased Q in the exercises containing a static component, and Pa varied with mode of exercise. Any generalized scheme of cardiovascular control during exercise must account for the potential influence of dynamic and static components of the exercise.

  7. Acute coronary hemodynamic effects of equihypotensive doses of nisoldipine and diltiazem

    NARCIS (Netherlands)

    H. Suryapranata (Harry); P.W.J.C. Serruys (Patrick); A.L. Soward; J. Planellas; G. Vanhaleweyk; P.G. Hugenholtz (Paul)

    1985-01-01

    textabstractThe hemodynamic effects of nisoldipine and diltiazem were investigated in two groups of patients undergoing investigation for suspected coronary artery disease. Emphasis was placed on the coronary hemodynamic changes. Approximately equihypotensive doses of these two calcium channel

  8. Methylene Blue Is Effective to Reverse Refractory Hemodynamic Instability due to Dimethoate Poisoning

    Directory of Open Access Journals (Sweden)

    Nick Youssefi

    2015-09-01

    Conclusion:MB treatment was effective to reverse hypotension and restore hemodynamic instability caused by dimethoate poisoning. This index case may pave way to further investigation of MB therapy for OP-induced hemodynamic instabilities.

  9. The Influence of Age on Hemodynamic Parameters During Rest and Exercise in Healthy Individuals

    DEFF Research Database (Denmark)

    Wolsk, Emil; Bakkestrøm, Rine; Thomsen, Jacob H

    2017-01-01

    OBJECTIVES: The authors sought to obtain hemodynamic estimates across a wide age span and in both sexes for future reference and compare these estimates with current guideline diagnostic hemodynamic thresholds for abnormal filling pressure and pulmonary hypertension. BACKGROUND: At present...

  10. Magnetic resonance imaging based noninvasive measurements of brain hemodynamics in neonates

    DEFF Research Database (Denmark)

    De Vis, Jill B; Alderliesten, Thomas; Hendrikse, Jeroen

    2016-01-01

    Perinatal disturbances of brain hemodynamics can have a detrimental effect on the brain's parenchyma with consequently adverse neurodevelopmental outcome. Noninvasive, reliable tools to evaluate the neonate's brain hemodynamics are scarce. Advances in magnetic resonance imaging have provided new...

  11. Quantification of collateral flow in humans: a comparison of angiographic, electrocardiographic and hemodynamic variables

    NARCIS (Netherlands)

    van Liebergen, R. A.; Piek, J. J.; Koch, K. T.; de Winter, R. J.; Schotborgh, C. E.; Lie, K. I.

    1999-01-01

    Evaluation of collateral vascular circulation according to hemodynamic variables and its relation to myocardial ischemia. There is limited information regarding the hemodynamic quantification of recruitable collateral vessels. Angiography of the donor coronary artery was performed before and during

  12. Impact of Diversity of Morphological Characteristics and Reynolds number on Local Hemodynamics in Basilar Aneurysms

    DEFF Research Database (Denmark)

    Rafat, Marjan; Dabagh, Mahsa; Heller, Martin

    2018-01-01

    management. Existing aneurysm hemodynamics studies generally evaluate limited geometries or Reynolds numbers (Re), which are difficult to apply to a wide range of patient-specific cases. We focused on the association between hemodynamic characteristics and morphology. We assessed several two-dimensional (2D...... in the hemodynamic and WSS profiles. Our systematic mapping and non-dimensional analysis qualitatively identify hemodynamic conditions that may predispose aneurysms to rupture. This article is protected by copyright. All rights reserved....

  13. [The hemodynamic characteristics of septic shock and relationship with syndrome types of traditional Chinese medicine].

    Science.gov (United States)

    He, Jianzhuo; Wang, Lei; Yin, Xin; Guo, Liheng; Zhang, Minzhou

    2016-02-01

    To observe hemodynamic characteristics and the correlation with syndrome types of traditional Chinese medicine (TCM) in patients with septic shock, so as to direct the treatment based on syndrome differentiation. A prospective observation was conducted. Sixty-eight patients with septic shock admitted to the Department of Critical Care Medicine of Dade Road General Hospital of Guangdong Hospital of TCM from January 2013 to July 2015 were enrolled. Pulse indicating continuous cardiac output (PiCCO) was used to monitor the hemodynamic changes, including heart rate (HR), mean arterial pressure (MAP), central venous pressure (CVP), cardiac index (CI), global end diastolic volume index (GEDVI), extravascular lung water index (EVLWI), maximum rate of the increase in pressure (dPmax) and systemic vascular resistance index (SVRI), for assessment of hemodynamics. According to the CI, the patients were divided into two groups , i.e. high CI group (CI ≥ 50.0 mL×s(-1)×m(-2), n = 34) and low CI group (CI characteristics of two groups were investigated. The TCM differentiation was conducted with "four syndromes and four methods", and the hemodynamic characteristics of different syndrome types were investigated, the correlation between the TCM syndrome factors and hemodynamic parameters was analyzed. The patients were divided into survival group and death group, and clinical parameters and hemodynamic characteristics were compared between two groups. The acute physiology and chronic health evaluation II (APACHEII) score and blood glucose of low CI group were higher than those of high CI group [APACHEII score: 24.4±7.2 vs. 19.8±7.4, t = -2.279, P = 0.023; blood glucose (mmol/L): 9.7 (7.7, 14.6) vs. 6.7 (5.6, 10.0), Z = -2.257, P = 0.024], CI and GEDVI were lowered [CI (mL×s(-1)×m(-2)): 36.7±8.3 vs. 68.4±16.7, t = 10.285, P = 0.000; GEDVI (mL/m(2)): 689.0 (566.0, 883.8) vs. 838.5 (692.8, 1?247.3), Z = -2.711, P = 0.007], while SVRI was increased [kPa×s×L(-1)×m(-2): 248

  14. Hemodynamic causes of exercise intolerance in Fontan patients

    DEFF Research Database (Denmark)

    Hebert, Anders; Jensen, Annette S; Mikkelsen, Ulla Ramer

    2014-01-01

    BACKGROUND: Exercise intolerance is frequent among Fontan patients and an important determinant for quality of life. This study investigated the hemodynamic causes of impaired exercise capacity in Fontan patients with particular focus on the influence of stroke volume index (SVI) and heart rate (HR...

  15. The hemodynamic basis of exercise intolerance in tricuspid regurgitation

    DEFF Research Database (Denmark)

    Andersen, Mads Jønsson; Nishimura, Rick a; Borlaug, Barry A

    2014-01-01

    BACKGROUND:Patients with severe tricuspid regurgitation (TR) frequently present with exertional fatigue and dyspnea, but the hemodynamic basis for exercise limitation in people with TR remains unclear. METHODS AND RESULTS:Twelve subjects with normal left ventricular (LV) ejection fraction and gra...

  16. Relationship Between Serum Uric Acid Levels and Intrarenal Hemodynamic Parameters

    Directory of Open Access Journals (Sweden)

    Hideki Uedono

    2015-06-01

    Full Text Available Background/Aims: Hyperuricemia has been reported to affect renal hemodynamics in rat models. We evaluate the relationship between serum uric acid and intrarenal hemodynamic parameters in humans, utilizing the plasma clearance of para-aminohippurate (CPAH and inulin (Cin. Methods: Renal and glomerular hemodynamics were assessed by simultaneous measurement of CPAH and Cin in 58 subjects. Of these, 19 subjects were planned to provide a kidney for transplantation; 26 had diabetes without proteinuria; and 13 had mild proteinuria. Renal and glomerular hemodynamics were calculated using Gomez`s formulae. Results: Cin was more than 60 ml/min/1.73m2 in all subjects. Serum uric acid levels correlated significantly with vascular resistance at the afferent arteriole (Ra (r = 0.354, p = 0.006 but not with that of the efferent arteriole (Re. Serum uric acid levels (β = 0.581, p = a after adjustment for several confounders (R2 = 0.518, p = Conclusions: These findings suggest, for the first time in humans, that higher serum uric acid levels are associated significantly with Ra in subjects with Cin > 60 ml/min/1.73m2. The increase in Ra in subjects with higher uric acid levels may be related to dysfunction of glomerular perfusion.

  17. Monitoring Detrusor Oxygenation and Hemodynamics Noninvasively during Dysfunctional Voiding

    Directory of Open Access Journals (Sweden)

    Andrew J. Macnab

    2012-01-01

    Full Text Available The current literature indicates that lower urinary tract symptoms (LUTSs related to benign prostatic hyperplasia (BPH have a heterogeneous pathophysiology. Pressure flow studies (UDSs remain the gold standard evaluation methodology for such patients. However, as the function of the detrusor muscle depends on its vasculature and perfusion, the underlying causes of LUTS likely include abnormalities of detrusor oxygenation and hemodynamics, and available treatment options include agents thought to act on the detrusor smooth muscle and/or vasculature. Hence, near infrared spectroscopy (NIRS, an established optical methodology for monitoring changes in tissue oxygenation and hemodynamics, has relevance as a means of expanding knowledge related to the pathophysiology of BPH and potential treatment options. This methodological report describes how to conduct simultaneous NIRS monitoring of detrusor oxygenation and hemodynamics during UDS, outlines the clinical implications and practical applications of NIRS, explains the principles of physiologic interpretation of NIRS voiding data, and proposes an exploratory hypothesis that the pathophysiological causes underlying LUTS include detrusor dysfunction due to an abnormal hemodynamic response or the onset of oxygen debt during voiding.

  18. Postnatal rearrangement of central hemodynamics in surgically born babies

    Directory of Open Access Journals (Sweden)

    T. S. Tumaeva

    2015-01-01

    Full Text Available Objective: to investigate the impact of complicated ante- and intranatal periods on postnatal cardiovascular hemodynamic adaptation in surgically born babies who have suffered hypoxia-ischemia. Patients and methods. A total of 382 full-term neonatal infants were examined. A study group included 117 cesarean born babies who had suffered hypoxia-ischemia. Comparison Group 1 comprised 150 infants who had been born by cesarean section and had no signs of cerebral ischemia. Comparison Group 2 consisted of 65 vaginally born babies following hypoxia-ischemia. A control group included 50 infants of physiological pregnancy and labor. In the first 1—2 days of life, all the neonates underwent EchoCG and determination of structural and hemodynamic parameters by using the standard procedures. Impaired postnatal hemodynamic rearrangement was found in all the babies of the examined groups, particular in those who had been born via cesarean section and sustained hypoxia-ischemia; the magnitude of disadaptation correlated with the severity of hypoxia-ischemia. A delayed reduction of dysfunction beyond the early neonatal period was noted in babies exposed to a combination of perinatal damaging factors. Conclusion. A set of poor ante- and intranatal factors contributes to impaired cardiac hemodynamic adaptation. The babies who have been born via cesarean section and sustained hypoxia-ischemia constitute a group at risk for cardiac abnormality in different age periods.

  19. Dietary melatonin alters uterine artery hemodynamics in pregnant holstein heifers

    Science.gov (United States)

    The objective was to examine uterine artery hemodynamics and maternal serum profiles in pregnant heifers supplemented with dietary melatonin (MEL) or no supplementation (CON). In addition, melatonin receptor–mediated responses in steroid metabolism were examined using a bovine endometrial epithelial...

  20. Initial approach to hypertension in the hemodynamics unit: review article

    Directory of Open Access Journals (Sweden)

    Gustavo Teixeira Fulton Schimit

    2013-06-01

    Full Text Available Correct identification and early management of hypertensive disorders should be a part of the therapeutic repertoire of every professional working in hemodynamics units. Based on recent publications, this study aims to propose a practical approach to the identification and early management of these disorders in this type of service.

  1. Vascular Adaptation to Exercise in Humans: Role of Hemodynamic Stimuli.

    NARCIS (Netherlands)

    Green, D.J.; Hopman, M.T.E.; Padilla, J.; Laughlin, M.H.; Thijssen, D.H.J.

    2017-01-01

    On the 400th anniversary of Harvey's Lumleian lectures, this review focuses on "hemodynamic" forces associated with the movement of blood through arteries in humans and the functional and structural adaptations that result from repeated episodic exposure to such stimuli. The late 20th century

  2. Monitoring Detrusor Oxygenation and Hemodynamics Noninvasively during Dysfunctional Voiding

    Science.gov (United States)

    Macnab, Andrew J.; Stothers, Lynn S.; Shadgan, Babak

    2012-01-01

    The current literature indicates that lower urinary tract symptoms (LUTSs) related to benign prostatic hyperplasia (BPH) have a heterogeneous pathophysiology. Pressure flow studies (UDSs) remain the gold standard evaluation methodology for such patients. However, as the function of the detrusor muscle depends on its vasculature and perfusion, the underlying causes of LUTS likely include abnormalities of detrusor oxygenation and hemodynamics, and available treatment options include agents thought to act on the detrusor smooth muscle and/or vasculature. Hence, near infrared spectroscopy (NIRS), an established optical methodology for monitoring changes in tissue oxygenation and hemodynamics, has relevance as a means of expanding knowledge related to the pathophysiology of BPH and potential treatment options. This methodological report describes how to conduct simultaneous NIRS monitoring of detrusor oxygenation and hemodynamics during UDS, outlines the clinical implications and practical applications of NIRS, explains the principles of physiologic interpretation of NIRS voiding data, and proposes an exploratory hypothesis that the pathophysiological causes underlying LUTS include detrusor dysfunction due to an abnormal hemodynamic response or the onset of oxygen debt during voiding. PMID:23019422

  3. Altering hemodynamics leads to congenital heart defects (Conference Presentation)

    Science.gov (United States)

    Ford, Stephanie M.; McPheeters, Matthew T.; Wang, Yves T.; Gu, Shi; Doughman, Yong Qiu; Strainic, James P.; Rollins, Andrew M.; Watanabe, Michiko; Jenkins, Michael W.

    2016-03-01

    The role of hemodynamics in early heart development is poorly understood. In order to successfully assess the impact of hemodynamics on development, we need to monitor and perturb blood flow, and quantify the resultant effects on morphology. Here, we have utilized cardiac optical pacing to create regurgitant flow in embryonic hearts and OCT to quantify regurgitation percentage and resultant morphology. Embryonic quail in a shell-less culture were optically paced at 3 Hz (well above the intrinsic rate or 1.33-1.67 Hz) on day 2 of development (3-4 weeks human) for 5 minutes. The pacing fatigued the heart and led to a prolonged period (> 1 hour) of increased regurgitant flow. Embryos were kept alive until day 3 (cardiac looping - 4-5 weeks human) or day 8 (4 chambered heart - 8 weeks human) to quantify resultant morphologic changes with OCT. All paced embryos imaged at day 3 displayed cardiac defects. The extent of regurgitant flow immediately after pacing was correlated with cardiac cushion size 24-hours post pacing (p-value cardio-facial/DiGeorge syndrome models suggesting that hemodynamics plays a role in these syndromes as well. Utilizing OCT and optical pacing to understand hemodynamics in development is an important step towards determining CHD mechanisms and ultimately developing earlier treatments.

  4. Physiological basis of clinically used coronary hemodynamic indices

    NARCIS (Netherlands)

    Spaan, Jos A. E.; Piek, Jan J.; Hoffman, Julien I. E.; Siebes, Maria

    2006-01-01

    In deriving clinically used hemodynamic indices such as fractional flow reserve and coronary flow velocity reserve, simplified models of the coronary circulation are used. In particular, myocardial resistance is assumed to be independent of factors such as heart contraction and driving pressure.

  5. Is the antiproteinuric effect of dipyridamole hemodynamically mediated

    NARCIS (Netherlands)

    de Jong, P. E.; van der Meer, J.; van der Hem, G. K.; de Zeeuw, D.

    1988-01-01

    We studied the acute antiproteinuric and renal hemodynamic effect of dipyridamole 30–60 mg intravenously in 13 salt-depleted patients with the nephrotic syndrome of different etiology. Whereas mean arterial pressure did not change, a small fall in glomerular filtration rate with a concomitant fall

  6. Occupational dosimetry in rela-time hemodynamics rooms. Usefulness of system dose-aware as a tool for learning; Dosimetria ocupacional en tiempo real en salas de hemodinamica. Utilidad del sistema dose-aware como herramienta formativa

    Energy Technology Data Exchange (ETDEWEB)

    Pinto Monedero, M.; Rodriguez Cobo, C.; Pifarre Martinez, X.; Ruiz Martin, J.; Barros Candelero, J. M.; Goicolea Ruigomez, J.; Diaz Blaires, G.; Garcia lunar, I.

    2013-07-01

    The work pursues a dual objective: on the one hand, to know the typical doses that practitioners of a dosimetry system interventional cardiology receive in real time, which allows to know the dose rate at any time; on the other hand, to assess the validity of this system of dosimetry, together with a simultaneous recording of proceedings for further analysis, as a teaching tool from the point of view of radiation protection. (Author)

  7. Phytochemical analysis and hemodynamic actions of Artemisia vulgaris L.

    Science.gov (United States)

    Tigno, X T; de Guzman, F; Flora, A M

    2000-01-01

    Artemisia vulgaris L. is widely used in the Philippines for its anti-inflammatory properties. The plant was cultivated and mature leaves were collected and washed. The dried leaves were extracted with both distilled water and chloroform. NMR data were obtained using a Varian Unity 500 MHz spectrophotometer. High and low-resolution mass spectra were obtained on a Finnigan MAT 96 high resolution gas chromatograph/mass spectrophotometer with a MAT ICIS operating system. The leaves yielded 2 sesquiterpene lactones and a novel aromatic compound. Two partition fractions from the aqueous extracts and four partition fractions from the chloroform extracts were tested on male Sprague-Dawley rats using both the in situ mesenteric circulation and the isolated perfused mesentery. In the isolated perfused rat mesentery, administration of 10% w/v solutions of water extract fractions FGN 63-1 and FGN 63-2 of A. vulgaris were highly effective in reversing the hypertensive action induced by norepinephrine, but they did not change the regional mesenteric pressures when given at baseline. In the intact rat, injection of 10 mg/ml of FGN 63-1 and chloroform extract FGN 64-2 did not significantly alter baseline blood pressures, but were able to reverse the increase in mean systolic and diastolic pressures induced by norepinephrine. The same fractions did not exert any significant effect on heart rate in either the normotensive or hypertensive states. The present data suggest that aqueous and chloroform extracts from leaves of A. vulgaris have anti-hypertensive actions but have no significant effects on cardiovascular hemodynamics under basal conditions.

  8. Comparison between arthroscopy and 3 dimensional double echo steady state 3D-DESS sequences in magnetic resonance imaging of internal derangements of the knee

    International Nuclear Information System (INIS)

    Dongola, Nagwa A.; Gishen, Philip

    2004-01-01

    This study was performed with the aim of evaluating the usefulness of 3 dimensional double-echo steady state sequences in examining the internal derangements of the knee. Arthroscopy was used as a referral standard. The study was performed in the Radiology and Arthroscopy Departments of Kings College Hospital, London, United Kingdom, during a 6-month period from January 1997 to June 1997. All patients who had knee magnetic resonance imaging within 3 months of arthroscopy were retrospectively studied. Thirty-three patients fulfilled these criteria and were selected. Three dimensional double-echo steady state sequences produced sensitivity for detecting meniscal tears of 87.5% for medial menisci (MM) and 75% for lateral menisci (LM). Specificity was 76% for MM and 96% for LM; positive predictive value (PPV) was 46.1% for MM and 85.7% for LM and negative predictive value (NPV) of 95% for MM and 96% for LM. The sensitivity for the anterior cruciate ligament was 83.3%, specificity was 77.7%, PPV was 45.4% and NPV was 95.4%. Three dimensional double-echo steady state sequences are useful in evaluating internal derangement of the knee, especially in advanced cartilage lesions. (author)

  9. Morphological study in internal derangement of the temporomandibular joint with MRI. The relationships between the state of the articular disc and limitation of motion of the mandibular head

    International Nuclear Information System (INIS)

    Miyazu, Hiroko; Sakurai, Takashi; Numayama, Sukenao; Furuya, Nobuaki; Kashima, Isamu

    1997-01-01

    In this study, we used MRI to investigate the relationships between these factors in temporomandibular joint (TMJ) patients, especially with regard to the range of condylar movement. Bone configurations and articular disc conditions were analyzed in a total of 367 TMJ of 255 internal derangement patients using MRI. We examined the influence of articular disc condition on functional disorder and identified the tendencies of the pathology of patients with internal derangements. Anterolateral displacement was more frequent than anteromedial displacement, and lateral rotary displacement was more frequent than medial rotary displacement. Therefore, the articular disc displaced more readily laterally, rather than medially. With regard to the relationship between the articular disc configuration and reduction, enlargement of the posterior band and biconvex discs showed a tendency for articular disc displacement that did not reduce, while discs with even thickness showed a tendency of articular disc displacement which would reduce. Folding and biconvexity tended to limit condylar movement while less limitation occurred with discs of even thickness. In cases of disc displacement without reduction, there was a significantly higher percentage of cases with limited condylar movement than in cases of displacement with reduction. (K.H.)

  10. Radionuclide assessment of peripheral hemodynamics: a new technique for measurement of forearm blood volume and flow

    Energy Technology Data Exchange (ETDEWEB)

    Todo, Y.; Tanimoto, M.; Yamamoto, T.; Iwasaki, T.

    1986-02-01

    A new peripheral hemodynamic measurement system using /sup 99m/Tc-labeled red blood cells has been developed. This method was carried out on 22 normal subjects, 29 with coronary artery disease, and two with dilated cardiomyopathy. Peripheral hemodynamic indices obtained from this method included forearm blood volume (FBV), venous capacity (FVC), venous capacity index (VCI), blood flow (FBF), and vascular resistance (FVR), and were compared with the central hemodynamic parameters of left ventricular filling pressure (LVFP), cardiac output (CO), and total systemic vascular resistance (TSVR) obtained with an invasive technique. The normal values were FBV 8.54 +/- 2.04 ml/100 ml; FVC 4.54 +/- 1.23 ml/100 ml; VCI 65.5 +/- 3.8%; FBF 4.26 +/- 0.56 ml/100 ml/min; and FVR 20.9 +/- 4.4 mmHg/ml/100 ml/min. These values were in good agreement with the values reported using conventional plethysmography. The 16 patients with congestive heart failure (NYHA Class II or III) showed significantly lower FBV, FVC, and FBF values and significantly higher VCI and FVR values than the healthy subjects. Capacitance vessel parameters (FBV, FVC, and VCI) and LVFP, FBF and CO, and FVR and TSVR each showed significant correlation; reproducibility was also good. The advantages of this method are (a) the detector does not come in contact with the region being measured; (b) it is possible to ascertain the absolute quantity of blood in the tissue; (c) extravasation of the plasma component can be ignored; and (d) data processing is simple.

  11. Art care: A multi-modality coronary 3D reconstruction and hemodynamic status assessment software.

    Science.gov (United States)

    Siogkas, Panagiotis K; Stefanou, Kostas A; Athanasiou, Lambros S; Papafaklis, Michail I; Michalis, Lampros K; Fotiadis, Dimitrios I

    2018-01-01

    Due to the incremental increase of clinical interest in the development of software that allows the 3-dimensional (3D) reconstruction and the functional assessment of the coronary vasculature, several software packages have been developed and are available today. Taking this into consideration, we have developed an innovative suite of software modules that perform 3D reconstruction of coronary arterial segments using different coronary imaging modalities such as IntraVascular UltraSound (IVUS) and invasive coronary angiography images (ICA), Optical Coherence Tomography (OCT) and ICA images, or plain ICA images and can safely and accurately assess the hemodynamic status of the artery of interest. The user can perform automated or manual segmentation of the IVUS or OCT images, visualize in 3D the reconstructed vessel and export it to formats, which are compatible with other Computer Aided Design (CAD) software systems. We employ finite elements to provide the capability to assess the hemodynamic functionality of the reconstructed vessels by calculating the virtual functional assessment index (vFAI), an index that corresponds and has been shown to correlate well to the actual fractional flow reserve (FFR) value. All the modules of the proposed system have been thoroughly validated. In brief, the 3D-QCA module, compared to a successful commercial software of the same genre, presented very good correlation using several validation metrics, with a Pearson's correlation coefficient (R) for the calculated volumes, vFAI, length and minimum lumen diameter of 0.99, 0.99, 0.99 and 0.88, respectively. Moreover, the automatic lumen detection modules for IVUS and OCT presented very high accuracy compared to the annotations by medical experts with the Pearson's correlation coefficient reaching the values of 0.94 and 0.99, respectively. In this study, we have presented a user-friendly software for the 3D reconstruction of coronary arterial segments and the accurate hemodynamic

  12. Heterogeneity of hemodynamic parameters in untreated primary hypertension, and individualization of antihypertensive therapy based on noninvasive hemodynamic measurements.

    Science.gov (United States)

    Aoka, Yoshikazu; Hagiwara, Nobuhisa; Kasanuki, Hiroshi

    2013-01-01

    Noninvasive measurement of hemodynamic parameter was undertaken in 240 patients with untreated primary hypertension using impedance cardiography (ICG) in outpatient clinics. High output was defined as a cardiac index (CI) >3.6 L/minute/m(2) and high resistance was defined as the total peripheral resistance index (TPRI) >2700 dyne·s·m(2)/cm(5). Of all patients, 67% had high-resistance hypertension (high TPRI with normal or low CI), and 16% had high-output hypertension (high CI with normal TPRI). Treatment with β-blockers for high-output hypertension and with calcium channel blockers for high-resistance hypertension reduced blood pressure equally, and restored normal hemodynamic balance, as reported in studies using invasive monitoring methods. These findings suggest that it is appropriate to use noninvasive ICG measurements to guide antihypertensive therapy. Multivariate analysis showed that female gender, tachycardia, and low body mass index (BMI) were associated with high-output hypertension, but age was not. Heterogeneity of hemodynamic parameters is thought to be one of the reasons why the efficacies of antihypertensive agents differ between patients. It may be feasible to predict which antihypertensive agent would be the most effective for a particular patient based on hemodynamic measurements or combination of gender, heart rate, and BMI.

  13. Occupational dosimetry in real time hemodynamic rooms. utility of the system Dose-aware as a training tool; Dosimetria ocupacional en tiempo real en salas de hemodinamica. Utilidad del Sistema Dose-Aware como herramienta formativa

    Energy Technology Data Exchange (ETDEWEB)

    Pinto Monedero, M.; Rodriguez Cobo, C.; Pifarre Martinez, X.; Ruiz Martin, J.; Barros Candelero, J. M.; Goicolea Ruigomez, J.; Diaz Blaires, G.; Garcia Lunar

    2014-02-01

    This paper presents the results from a study in a real time dosimetry system used in the catheter laboratory room of our center. The objective was to know the occupational doses per procedure, on the one hand, and, on the other hand, to evaluate its utility as a learning tool for radiation protection purposes with the simultaneous video recording of the interventions. 83 diagnostic and therapeutic procedures were analyzed, and an average dose per procedure of 0,37 {mu}Sv and 0,10 {mu}Sv for the main cardiologist and nurse were obtained, respectively. 36 of these interventions were also recorded and the images were synchronized with the dosimetric information stored and the dosimetry system. The findings were presented to the interventional cardiology team in a learning session. They showed a high level of satisfaction with this new method of optimizing the occupational doses through a customized learning session. (Author)

  14. Evaluation of plain radiograph in mitral stenosis related to hemodynamics

    Energy Technology Data Exchange (ETDEWEB)

    Choe, Ku Ok; Suh, Jung Ho; Park, Chang Yun; Choi, Byung So [Yonsei University College of Medicine, Seoul (Korea, Republic of)

    1973-04-15

    Mitral stenosis, the most frequent heart disease in adult, showed relatively characteristic pulmonary findings in plain chest X-ray. In recent years the knowledge of the altered physiology of hemodynamics could offer considerable amount of hemodynamic barrier in plain chest. But the value of several parameters was still controversial. In this study a variety of roentgen signs were related to physiologic data and those were acquired by the cardiac catheterization in total of 67 cases of mitral stenosis. 1. Correlation of DPA/DHT ratio (Diameter of pulmonary arterial segment/ Diameter of hemithorax X 100) to hemodynamic data; The pulmonary arterial segments was dilated by two factors, the one was pulmonary blood flow and the other the blood pressure within it. In mitral stenosis, the cardiac output was decreased to quite uniform level, hence measurement of pulmonary arterial segment might be valuable. The correlation coefficient of DPA/ DHT ratio to hemodynamic data were as follows: 0.54 to mean pulmonary artery pressure, 0.32 to pulmonary capillary wedge pressure, -0.37 to mitral valvular area and 0.07 to pulmonary vascular resistance. No significant difference was noted in between pure mitral stenosis and mitral stenosis associated with other valvular disease. 2. Correlation of diameter of right descending pulmonary artery to hemodynamic data: The measurement was made near the first bifurcation of right descending pulmonary artery at its widest point. Pulmonary vascular pattern was best correlated (r=0.71). Another had rough correlation: 0.05 to mean pulmonary artery pressure, 0.31 to pulmonary capillary wedge pressure, -0.44 to mitral valvular area in correlation coefficient. No pulmonary arterial hypertension was observed in the cases diameter of less than 12 mm, but all except two cases had pulmonary hypertension in which diameter exceeded 16 mm. According to increase of the mean pulmonary arterial pressure, the same increment in pressure increased change

  15. The central hemodynamics at the newborns from the radionuclide contaminated territories

    International Nuclear Information System (INIS)

    Kalyuzhin, V.G.; Voskresenskaya, T.V.; Deryugina, O.A.; Adas'ko, V.I.; Platonova, O.A.

    1995-01-01

    As known the cardiovascular system has enough high radiosensitivity. The operation features of the central part of a cardiovascular system of newborns living on contaminated territories were studied. The screening research of a cardiovascular system state of 50 newborns from regions with contamination by 137 Cs more than 15 Ci/sq.km were conducted. The obtained data were compared with results of the similar investigation of 30 newborns from a control 'clean' regions. Is revealed that for newborns from a contaminated zone the more stressed in comparison with one from control group the hemodynamics adaptation process of the central link of a cardiovascular system is characteristic, especially in the first days of a life. For newborns with the disadaptation of a cardiovascular system the constant control for the circulatory homeostasis parameters and more sparing mode of a care in the first days of a life is required. 7 refs., 1 tab

  16. Increased hippocampal, thalamic, and prefrontal hemodynamic response to an urban noise stimulus in schizophrenia.

    Science.gov (United States)

    Tregellas, Jason R; Ellis, Jamey; Shatti, Shireen; Du, Yiping P; Rojas, Donald C

    2009-03-01

    People with schizophrenia often have difficulty ignoring unimportant noises in the environment. While experimental measures of sensory gating have yielded insight into neurobiological mechanisms related to this deficit, the degree to which these measures reflect the real-world experience of people with schizophrenia is unknown. The goal of this study was to develop a clinically relevant sensory gating paradigm and to assess differences in brain hemodynamic responses during the task in schizophrenia. Thirty-five participants, including 18 outpatients with schizophrenia and 17 healthy comparison subjects, underwent scanning on a 3-T MR system while passively listening to an "urban white noise" stimulus, a mixture of common sounds simulating a busy urban setting, including multiple conversations and events recorded from a neighborhood gathering, music, and talk radio. P50 evoked responses from a typical paired-click sensory gating task also were measured. Listening to the urban white noise stimulus produced robust activation of the auditory pathway in all participants. Activation was observed in the bilateral primary and secondary auditory cortices, medial geniculate nuclei, and inferior colliculus. Greater activation was observed in the schizophrenia patients relative to the comparison subjects in the hippocampus, thalamus, and prefrontal cortex. Higher P50 test/conditioning ratios also were observed in the schizophrenia patients. These evoked responses correlated with hemodynamic responses in the hippocampus and the prefrontal cortex. The finding of greater activation of the hippocampus, thalamus, and prefrontal cortex during a sensory gating task with high face validity further supports the involvement of these brain regions in gating deficits in schizophrenia. This link is strengthened by the observed correlation between evoked responses in the paired-click paradigm and hemodynamic responses in a functional MRI sensory gating paradigm.

  17. Bench-to-bedside review: An approach to hemodynamic monitoring--Guyton at the bedside.

    Science.gov (United States)

    Magder, Sheldon

    2012-10-29

    Hemodynamic monitoring is used to identify deviations from hemodynamic goals and to assess responses to therapy. To accomplish these goals one must understand how the circulation is regulated. In this review I begin with an historical review of the work of Arthur Guyton and his conceptual understanding of the circulation and then present an approach by which Guyton's concepts can be applied at the bedside. Guyton argued that cardiac output and central venous pressure are determined by the interaction of two functions: cardiac function, which is determined by cardiac performance; and a return function, which is determined by the return of blood to the heart. This means that changes in cardiac output are dependent upon changes of one of these two functions or of both. I start with an approach based on the approximation that blood pressure is determined by the product of cardiac output and systemic vascular resistance and that cardiac output is determined by cardiac function and venous return. A fall in blood pressure with no change in or a rise in cardiac output indicates that a decrease in vascular resistance is the dominant factor. If the fall in blood pressure is due to a fall in cardiac output then the role of a change in the return function and cardiac function can be separated by the patterns of changes in central venous pressure and cardiac output. Measurement of cardiac output is a central component to this approach but until recently it was not easy to obtain and was estimated from surrogates. However, there are now a number of non-invasive devices that can give measures of cardiac output and permit the use of physiological principles to more rapidly appreciate the primary pathophysiology behind hemodynamic abnormalities and to provide directed therapy.

  18. Hemodynamic Effects of Noninvasive Ventilation in Patients with Venocapillary Pulmonary Hypertension

    Directory of Open Access Journals (Sweden)

    André Moreira Bento

    2014-11-01

    Full Text Available Background: The hemodynamic effects of noninvasive ventilation with positive pressure in patients with pulmonary hypertension without left ventricular dysfunction are not clearly established. Objectives: Analyze the impact of increasing airway pressure with continuous positive airway pressure on hemodynamic parameters and, in particular, on cardiac output in patients with variable degrees of pulmonary hypertension. Methods: The study included 38 patients with pulmonary hypertension caused by mitral stenosis without left ventricular dysfunction or other significant valvulopathy. The hemodynamic state of these patients was analyzed in three conditions: baseline, after continuous positive pressure of 7 cmH2O and, finally, after pressure of 14 cmH2O. Results: The population was composed of predominantly young and female individuals with significant elevation in pulmonary arterial pressure (mean systolic pressure of 57 mmHg. Of all variables analyzed, only the right atrial pressure changed across the analyzed moments (from the baseline condition to the pressure of 14 cmH2O there was a change from 8 ± 4 mmHg to 11 ± 3 mmHg, respectively, p = 0.031. Even though there was no variation in mean cardiac output, increased values in pulmonary artery pressure were associated with increased cardiac output. There was no harmful effect or other clinical instability associated with use application of airway pressure. Conclusion: In patients with venocapillary pulmonary hypertension without left ventricular dysfunction, cardiac output response was directly associated with the degree of pulmonary hypertension. The application of noninvasive ventilation did not cause complications directly related to the ventilation systems.

  19. Patient-specific in vitro models for hemodynamic analysis of congenital heart disease - Additive manufacturing approach.

    Science.gov (United States)

    Medero, Rafael; García-Rodríguez, Sylvana; François, Christopher J; Roldán-Alzate, Alejandro

    2017-03-21

    Non-invasive hemodynamic assessment of total cavopulmonary connection (TCPC) is challenging due to the complex anatomy. Additive manufacturing (AM) is a suitable alternative for creating patient-specific in vitro models for flow measurements using four-dimensional (4D) Flow MRI. These in vitro systems have the potential to serve as validation for computational fluid dynamics (CFD), simulating different physiological conditions. This study investigated three different AM technologies, stereolithography (SLA), selective laser sintering (SLS) and fused deposition modeling (FDM), to determine differences in hemodynamics when measuring flow using 4D Flow MRI. The models were created using patient-specific MRI data from an extracardiac TCPC. These models were connected to a perfusion pump circulating water at three different flow rates. Data was processed for visualization and quantification of velocity, flow distribution, vorticity and kinetic energy. These results were compared between each model. In addition, the flow distribution obtained in vitro was compared to in vivo. The results showed significant difference in velocities measured at the outlets of the models that required internal support material when printing. Furthermore, an ultrasound flow sensor was used to validate flow measurements at the inlets and outlets of the in vitro models. These results were highly correlated to those measured with 4D Flow MRI. This study showed that commercially available AM technologies can be used to create patient-specific vascular models for in vitro hemodynamic studies at reasonable costs. However, technologies that do not require internal supports during manufacturing allow smoother internal surfaces, which makes them better suited for flow analyses. Copyright © 2017 Elsevier Ltd. All rights reserved.

  20. Race predictors and hemodynamic alteration after an ultra-trail marathon race.

    Science.gov (United States)

    Taksaudom, Noppon; Tongsiri, Natee; Potikul, Amarit; Leampriboon, Chawakorn; Tantraworasin, Apichat; Chaiyasri, Anong

    2017-01-01

    Unique rough-terrain ultra-trail running races have increased in popularity. Concerns regarding the suitability of the candidates make it difficult for organizers to manage safety regulations. The purpose of this study was to identify possible race predictors and assess hemodynamic change after long endurance races. We studied 228 runners who competed in a 66 km-trail running race. A questionnaire and noninvasive hemodynamic flow assessment including blood pressure, heart rate, stroke volume, stroke volume variation, systemic vascular resistance, cardiac index, and oxygen saturation were used to determine physiologic alterations and to identify finish predictors. One hundred and thirty volunteers completed the questionnaire, 126 participants had a prerace hemodynamic assessment, and 33 of these participants completed a postrace assessment after crossing the finish line. The participants were divided into a finisher group and a nonfinisher group. The average age of all runners was 37 years (range of 24-56 years). Of the 228 runners, 163 (71.5%) were male. There were 189 (82.9%) finishers. Univariable analysis indicated that the finish predictors included male gender, longest distance ever run, faster running records, and lower diastolic pressure. Only a lower diastolic pressure was a significant predictor of race finishing (diastolic blood pressure 74-84 mmHg: adjusted odd ratio 3.81; 95% confidence interval [CI] =1.09-13.27 and diastolic blood pressure resistance and cardian index did not change significantly. The only race finishing predictor from the multivariable analysis was lower diastolic pressure. Finishers seem to have a hypovolemic physiologic response and a lower level of oxygen saturation.

  1. Measurement of hemodynamic changes with the axial flow blood pump installed in descending aorta.

    Science.gov (United States)

    Okamoto, Eiji; Yano, Tetsuya; Miura, Hidekazu; Shiraishi, Yasuyuki; Yambe, Tomoyuki; Mitamura, Yoshinori

    2017-12-01

    We have developed various axial flow blood pumps to realize the concept of the Valvo pump, and we have studied hemodynamic changes under cardiac assistance using an axial flow blood pump in series with the natural heart. In this study, we measured hemodynamic changes of not only systemic circulation but also cerebral circulation and coronary circulation under cardiac support using our latest axial flow blood pump placed in the descending aorta in an acute animal experiment. The axial flow blood pump was installed at the thoracic descending aorta through a left thoracotomy of a goat (43.8 kg, female). When the pump was on, the aortic pressure and aortic flow downstream of the pump increased with preservation of pulsatilities. The pressure drop upstream of the pump caused reduction of afterload pressure, and it may lead to reduction of left ventricular wall stress. However, cerebral blood flow and coronary blood flow were decreased when the pump was on. The axial flow blood pump enables more effective blood perfusion into systemic circulation, but it has the potential risk of blood perfusion disturbance into cerebral circulation and coronary circulation. The results indicate that the position before the coronary ostia might be suitable for implantation of the axial flow blood pump in series with the natural heart to avoid blood perfusion disturbances.

  2. Hemodynamic benefit of multiple programmable pacing configurations in patients with biventricular pacemakers.

    Science.gov (United States)

    Balasundaram, Ramprakash; Rao, Hygriv B; Sridevi, C; Somaraju, B; Singh, Balbir; Calambur, Narasimhan

    2009-03-01

    Cardiac resynchronization therapy (CRT) is an established treatment for patients with heart failure. However, one-third of the patients fail to improve with this therapy. Stimulation with different left ventricular stimulation (LVS) configurations has been used to prevent diaphragmatic capture and to decrease the capture thresholds. We evaluated the hemodynamic effects of different LVS configurations using echocardiography. Recipients of CRT systems capable of multiple LVS configurations were studied. Biventricular capture was confirmed for each polarity and echocardiographic measurements were made. The atrioventricular and interventricular delays were optimized and kept constant during the study. The cardiac output (CO), myocardial performance index (MPI), and severity of mitral regurgitation (MR) were recorded for all LVS configurations and compared for the best and the worst configurations, determined by CO. We studied 10 men and four women, 55 +/- 13 years of age on average. The CO and MPI changed significantly by changing the LVS configurations. The difference in CO ranged from 0.3 to 1.5 L, and seven patients (50%) showed > or =20% difference in CO between best and worst LVS configurations. Severity of MR decreased by > or =1 grade in nine patients, while in two patients MR worsened despite improvement in CO. Changing the LVS configuration changes hemodynamic function in some CRT system recipients.

  3. Impact of Clipping versus Coiling on Postoperative Hemodynamics and Pulmonary Edema after Subarachnoid Hemorrhage

    Directory of Open Access Journals (Sweden)

    Nobutaka Horie

    2014-01-01

    Full Text Available Volume management is critical for assessment of cerebral vasospasm after aneurysmal subarachnoid hemorrhage (SAH. This multicenter prospective cohort study compared the impact of surgical clipping versus endovascular coiling on postoperative hemodynamics and pulmonary edema in patients with SAH. Hemodynamic parameters were measured for 14 days using a transpulmonary thermodilution system. The study included 202 patients, including 160 who underwent clipping and 42 who underwent coiling. There were no differences in global ejection fraction (GEF, cardiac index, systemic vascular resistance index, or global end-diastolic volume index between the clipping and coiling groups in the early period. However, extravascular lung water index (EVLWI and pulmonary vascular permeability index (PVPI were significantly higher in the clipping group in the vasospasm period. Postoperative C-reactive protein (CRP level was higher in the clipping group and was significantly correlated with postoperative brain natriuretic peptide level. Multivariate analysis found that PVPI and GEF were independently associated with high EVLWI in the early period, suggesting cardiogenic edema, and that CRP and PVPI, but not GEF, were independently associated with high EVLWI in the vasospasm period, suggesting noncardiogenic edema. In conclusion, clipping affects postoperative CRP level and may thereby increase noncardiogenic pulmonary edema in the vasospasm period. His trial is registered with University Hospital Medical Information Network UMIN000003794.

  4. Use of Diazepam to Correct Hemodynamic Changes in Explosive Mine Injury: Experimental Study

    Directory of Open Access Journals (Sweden)

    V. N. Yelsky

    2007-01-01

    Full Text Available Objective. To study the hemodynamic effect of benzodiazepine tranquilizers in explosive mine injury in an experiment.Materials and methods. The study was performed on non-inbred male rats; hemodynamic parameters were examined at the systemic, organ, and microcirculatory levels.Results. Circulatory adaptive changes occurring at the beginning of a premorbid load further become pathogenic, which in combination with a progressive change in blood-brain barrier resistance results in the severer course of premorbid load-complicated explosive mine injury than that of isolated one. Correction of occurring disorders, by stimulating the stress-limiting GABAergic system with diazepam, is most effective within the first 25 minutes after isolated explosive mine injury and within the first 15 minutes after complicated one. Conclusion. Under the conditions of deep collieries where medical aid was generally late, emergency medical activation of urgent adaptation mechanisms by the techniques specially developed by the authors for these conditions is the most effective way of preventing the complications of explosive mine injury. 

  5. Coupled plasma filtration adsorption improves hemodynamics in septic shock.

    Science.gov (United States)

    Franchi, Matteo; Giacalone, Marilù; Traupe, Ippolito; Rago, Rocco; Baldi, Giacomo; Giunta, Francesco; Forfori, Francesco

    2016-06-01

    Septic shock involves a dysregulation of the immune response to an infection. This may lead to hemodynamic dysfunction and multiple-organ failure. The main aim of this study was to evaluate the effect of coupled plasma filtration adsorption (CPFA) on the hemodynamic profile in patients with septic shock. We retrospectively analyzed data from 21 adult patients admitted to the intensive care unit with a diagnosis of septic shock, comparing data between pre-CPFA and post-CPFA treatment. They received a maximum of 5 cycles of treatment. Coupled plasma filtration adsorption treatment was associated with a significant increase of mean arterial pressure (P septic shock patients, ameliorating organ failure. Copyright © 2016 Elsevier Inc. All rights reserved.

  6. Hemodynamic effects of microgravity and their ground-based simulations

    Science.gov (United States)

    Lobachik, V. I.; Abrosimov, S. V.; Zhidkov, V. V.; Endeka, D. K.

    Hemodynamic effects of simulated microgravity were investigated, in various experiments, using radioactive isotopes, in which 40 healthy men, aged 35 to 42 years, took part. Blood shifts were evaluated qualitatively and quantitatively. Simulation studies included bedrest, head-down tilt (-5° and -15°), and vertical water immersion, it was found that none of the methods could entirely simulate hemodynamic effects of microgravity. Subjective sensations varied in a wide range. They cannot be used to identify reliably the effects of real and simulated microgravity. Renal fluid excretion in real and simulated microgravity was different in terms of volume and time. The experiments yielded data about the general pattern of circulation with blood displaced to the upper body.

  7. Effects of an interatrial shunt on rest and exercise hemodynamics

    DEFF Research Database (Denmark)

    Kaye, David; Shah, Sanjiv J; Borlaug, Barry A

    2014-01-01

    BACKGROUND: A treatment based on an interatrial shunt device has been proposed for counteracting elevated pulmonary capillary wedge pressure (PCWP) in patients with heart failure and mildly reduced or preserved ejection fraction (HFpEF). We tested the theoretical hemodynamic effects...... of the conditions tested. CONCLUSIONS: The interatrial shunt reduced left-sided cardiac output with a marked reduction in PCWP. This approach may reduce the propensity for heart failure exacerbations and allow patients to exercise longer, thus attaining higher heart rates and cardiac outputs with the shunt compared...... of this approach with the use of a previously validated cardiovascular simulation. METHODS AND RESULTS: Rest and exercise hemodynamics data from 2 previous independent studies of patients with HFpEF were simulated. The theoretical effects of a shunt between the right and left atria (diameter up to 12 mm) were...

  8. The impact of temporal regularization on estimates of the BOLD hemodynamic response function: a comparative analysis.

    Science.gov (United States)

    Casanova, Ramon; Ryali, Srikanth; Serences, John; Yang, Lucie; Kraft, Robert; Laurienti, Paul J; Maldjian, Joseph A

    2008-05-01

    In fMRI data analysis it has been shown that for a wide range of situations the hemodynamic response function (HRF) can be reasonably characterized as the impulse response function of a linear and time invariant system. An accurate and robust extraction of the HRF is essential to infer quantitative information about the relative timing of the neuronal events in different brain regions. When no assumptions are made about the HRF shape, it is most commonly estimated using time windowed averaging or a least squares estimated general linear model based on either Fourier or delta basis functions. Recently, regularization methods have been employed to increase the estimation efficiency of the HRF; typically these methods produce more accurate HRF estimates than the least squares approach [Goutte, C., Nielsen, F.A., Hansen, L.K., 2000. Modeling the Haemodynamic Response in fMRI Using Smooth FIR Filters. IEEE Trans. Med. Imag. 19(12), 1188-1201.]. Here, we use simulations to clarify the relative merit of temporal regularization based methods compared to the least squares methods with respect to the accuracy of estimating certain characteristics of the HRF such as time to peak (TTP), height (HR) and width (W) of the response. We implemented a Bayesian approach proposed by Marrelec et al. [Marrelec, G., Benali, H., Ciuciu, P., Pelegrini-Issac, M., Poline, J.-B., 2003. Robust Estimation of the Hemodynamic Response Function in Event-Related BOLD fMRI Using Basic Physiological Information. Hum. Brain Mapp. 19, 1-17., Marrelec, G., Benali, H., Ciuciu, P., Poline, J.B. Bayesian estimation of the hemodynamic of the hemodynamic response function in functional MRI. In: R. F, editor; 2001; Melville. p 229-247.] and its deterministic counterpart based on a combination of Tikhonov regularization [Tikhonov, A.N., Arsenin, V.Y., 1977. Solution of ill-posed problems. Washington DC: W.H. Winston.] and generalized cross-validation (GCV) [Wahba, G., 1990. Spline Models for Observational Data

  9. Static and Functional Hemodynamic Profiles of Women with Abnormal Uterine Artery Doppler at 22-24 Weeks of Gestation.

    Directory of Open Access Journals (Sweden)

    Åse Vårtun

    Full Text Available To compare cardiac function, systemic hemodynamics and preload reserve of women with increased (cases and normal (controls uterine artery (UtA pulsatility index (PI at 22-24 weeks of gestation.A prospective cross-sectional study of 620 pregnant women. UtA blood flow velocities were measured using Doppler ultrasonography, and PI was calculated. Mean UtA PI ≥ 1.16 (90th percentile was considered abnormal. Maternal hemodynamics was investigated at baseline and during passive leg raising (PLR using impedance cardiography (ICG. Preload reserve was defined as percent increase in stroke volume (SV 90 seconds after passive leg raising compared to baseline.Mean UtA PI was 1.49 among cases (n = 63 and 0.76 among controls (n = 557 (p < 0.0001. Eighteen (28.6% cases and 53 (9.5% controls developed pregnancy complications (p <0.0001. The mean arterial pressure and systemic vascular resistance were 83 mmHg and 1098.89±293.87 dyne s/cm5 among cases and 79 mmHg and 1023.95±213.83 dyne s/cm5 among controls (p = 0.007 and p = 0.012, respectively. Heart rate, SV and cardiac output were not different between the groups. Both cases and controls responded with a small (4-5% increase in SV in response to PLR, but the cardiac output remained unchanged. The preload reserve was not significantly different between two groups.Pregnant women with abnormal UtA PI had higher blood pressure and systemic vascular resistance, but similar functional hemodynamic profile at 22-24 weeks compared to controls. Further studies are needed to clarify whether functional hemodynamic assessment using ICG can be useful in predicting pregnancy complications.

  10. Hemodynamic Response Alterations in Sensorimotor Areas as a Function of Barbell Load Levels during Squatting: An fNIRS Study

    Directory of Open Access Journals (Sweden)

    Rouven Kenville

    2017-05-01

    Full Text Available Functional near-infrared spectroscopy (fNIRS serves as a promising tool to examine hemodynamic response alterations in a sports-scientific context. The present study aimed to investigate how brain activity within the human motor system changes its processing in dependency of different barbell load conditions while executing a barbell squat (BS. Additionally, we used different fNIRS probe configurations to identify and subsequently eliminate potential exercise induced systemic confounders such as increases in extracerebral blood flow. Ten healthy, male participants were enrolled in a crossover design. Participants performed a BS task with random barbell load levels (0% 1RM (1 repetition maximum, 20% 1RM and 40% 1RM for a BS during fNIRS recordings. Initially, we observed global hemodynamic response alterations within and outside the human motor system. However, short distance channel regression of fNIRS data revealed a focalized hemodynamic response alteration within bilateral superior parietal lobe (SPL for oxygenated hemoglobin (HbO2 and not for deoxygenated hemoglobin (HHb when comparing different load levels. These findings indicate that the previously observed load/force-brain relationship for simple and isolated movements is also present in complex multi-joint movements such as the BS. Altogether, our results show the feasibility of fNIRS to investigate brain processing in a sports-related context. We suggest for future studies to incorporate short distance channel regression of fNIRS data to reduce the likelihood of false-positive hemodynamic response alterations during complex whole movements.

  11. Pharmacological Modulation of Hemodynamics in Adult Zebrafish In Vivo.

    Directory of Open Access Journals (Sweden)

    Daniel Brönnimann

    Full Text Available Hemodynamic parameters in zebrafish receive increasing attention because of their important role in cardiovascular processes such as atherosclerosis, hematopoiesis, sprouting and intussusceptive angiogenesis. To study underlying mechanisms, the precise modulation of parameters like blood flow velocity or shear stress is centrally important. Questions related to blood flow have been addressed in the past in either embryonic or ex vivo-zebrafish models but little information is available for adult animals. Here we describe a pharmacological approach to modulate cardiac and hemodynamic parameters in adult zebrafish in vivo.Adult zebrafish were paralyzed and orally perfused with salt water. The drugs isoprenaline and sodium nitroprusside were directly applied with the perfusate, thus closely resembling the preferred method for drug delivery in zebrafish, namely within the water. Drug effects on the heart and on blood flow in the submental vein were studied using electrocardiograms, in vivo-microscopy and mathematical flow simulations.Under control conditions, heart rate, blood flow velocity and shear stress varied less than ± 5%. Maximal chronotropic effects of isoprenaline were achieved at a concentration of 50 μmol/L, where it increased the heart rate by 22.6 ± 1.3% (n = 4; p < 0.0001. Blood flow velocity and shear stress in the submental vein were not significantly increased. Sodium nitroprusside at 1 mmol/L did not alter the heart rate but increased blood flow velocity by 110.46 ± 19.64% (p = 0.01 and shear stress by 117.96 ± 23.65% (n = 9; p = 0.03.In this study, we demonstrate that cardiac and hemodynamic parameters in adult zebrafish can be efficiently modulated by isoprenaline and sodium nitroprusside. Together with the suitability of the zebrafish for in vivo-microscopy and genetic modifications, the methodology described permits studying biological processes that are dependent on hemodynamic alterations.

  12. Hemodynamic Consequences of Laparoscopy for Patients on Mechanical Circulatory Support.

    Science.gov (United States)

    Reich, Heidi; Ramzy, Danny; Czer, Lawrence; Esmailian, Fardad; Moriguchi, Jaime; Ihnken, Kai; Yusufali, Taizoon; D'Attellis, Nicola; Arabia, Francisco; Annamalai, Alagappan

    2015-12-01

    Technologic advances and superior survival with mechanical circulatory support (MCS) have led to an expanding population that develops intraabdominal conditions requiring intervention. Whether laparoscopy can be performed without detrimental effects on hemodynamics and device function is not well described. Effects of laparoscopy performed on MCS were retrospectively assessed. Intraoperative hemodynamics and device function were compared with the same time interval 24 hours prior to surgery using intrapatient paired t tests. Outcomes included survival, transfusion, thromboembolic events, and infection. Twelve patients with ventricular assist devices or total artificial hearts underwent laparoscopy from 2012 to 2014. Median follow-up was 116 days. Operations included cholecystectomy, diagnostic laparoscopy, gastrojejunostomy, and gastrostomy. There were no differences between preoperative and intraoperative mean arterial pressure, heart rate, and inotrope or vasopressor requirements (P > .05). Device fill volume, flow, rate, and power were unchanged (P > .05), whereas pulsatility index decreased by 0.2 (95% confidence interval, 0.03, 0.36) with laparoscopy (P = .03). All intraoperative fluctuations in hemodynamics and device function improved with reduction of pneumoperitoneum, adjusting device speed, or pharmacologic support. There were no operative mortalities. Thirty-day survival and survival to discharge were 75% and 50%, respectively. Despite antiplatelet therapy and preoperative international normalization ratio of 2.2 ± 0.9, there were no re-operations for bleeding, and 50% did not require transfusion. Two patients with recent cardiac surgery had thromboembolic events: one stroke and one device thrombus. None had postoperative bacteremia or driveline infection. Laparoscopy can be performed on MCS with low morbidity and mortality and minimal perturbations in hemodynamics and device function.

  13. Morphological and hemodynamic analysis of mirror posterior communicating artery aneurysms.

    Directory of Open Access Journals (Sweden)

    Jinyu Xu

    Full Text Available BACKGROUND AND PURPOSE: Hemodynamic factors are commonly believed to play an important role in the pathogenesis, progression, and rupture of cerebral aneurysms. In this study, we aimed to identify significant hemodynamic and morphological parameters that discriminate intracranial aneurysm rupture status using 3-dimensional-angiography and computational fluid dynamics technology. MATERIALS AND METHODS: 3D-DSA was performed in 8 patients with mirror posterior communicating artery aneurysms (Pcom-MANs. Each pair was divided into ruptured and unruptured groups. Five morphological and three hemodynamic parameters were evaluated for significance with respect to rupture. RESULTS: The normalized mean wall shear stress (WSS of the aneurysm sac in the ruptured group was significantly lower than that in the unruptured group (0.52±0.20 versus 0.81±0.21, P = .012. The percentage of the low WSS area in the ruptured group was higher than that in the unruptured group (4.11±4.66% versus 0.02±0.06%, P = .018. The AR was 1.04±0.21 in the ruptured group, which was significantly higher than 0.70±0.17 in the unruptured group (P = .012. By contrast, parameters that had no significant differences between the two groups were OSI (P = .674, aneurysm size (P = .327, size ratio (P = .779, vessel angle (P = 1.000 and aneurysm inclination angle (P = 1.000. CONCLUSIONS: Pcom-MANs may be a useful disease model to investigate possible causes of aneurysm rupture. The ruptured aneurysms manifested lower WSS, higher percentage of low WSS area, and higher AR, compared with the unruptured one. And hemodynamics is as important as morphology in discriminating aneurysm rupture status.

  14. Computational hemodynamics theory, modelling and applications

    CERN Document Server

    Tu, Jiyuan; Wong, Kelvin Kian Loong

    2015-01-01

    This book discusses geometric and mathematical models that can be used to study fluid and structural mechanics in the cardiovascular system.  Where traditional research methodologies in the human cardiovascular system are challenging due to its invasive nature, several recent advances in medical imaging and computational fluid and solid mechanics modelling now provide new and exciting research opportunities. This emerging field of study is multi-disciplinary, involving numerical methods, computational science, fluid and structural mechanics, and biomedical engineering. Certainly any new student or researcher in this field may feel overwhelmed by the wide range of disciplines that need to be understood. This unique book is one of the first to bring together knowledge from multiple disciplines, providing a starting point to each of the individual disciplines involved, attempting to ease the steep learning curve. This book presents elementary knowledge on the physiology of the cardiovascular system; basic knowl...

  15. [Hemodynamic analysis of a centrifugal blood pump].

    Science.gov (United States)

    Wang, Yang; Yang, Ming; Xu, Zihao; Zhuang, Xiaoqi; Li, Qilei; Xu, Liang

    2015-01-01

    This paper built the mathematical model of a centrifugal blood pump, which was designed by ourselves, combined it with that of the human cardiovascular system and simulated the coupling system using Matlab. Then we set up the experiment platform, linked the blood pump to mock human cardiovascular system in case of three-stage heart failure, and measured aortic pressure and flow under different speed. The comparison between experiment results and simulation results not only indicates the coupling model is correct and the blood pump works well, but also shows that with the increase of blood pump speed, the pulsation of aortic pressure and flow will be reduced, this situation will affect the structure and function of blood vessels.

  16. [Study on Indicator Densitometry Determination Method of Hemodynamic Parameters].

    Science.gov (United States)

    Liu, Guang-da; Zhou, Run-dong; Zha, Yu-tong; Cai, Jing; Niu, Jun-qi; Gao, Pu-jun; Liu, Li-li

    2016-03-01

    Measurement for hemodynamic parameters has always been a hot spot of clinical research. Methods for measuring hemodynamic parameters clinically have the problems of invasiveness, complex operation and being unfit for repeated measurement. To solve the problems, an indicator densitometry analysis method is presented based on near-infrared spectroscopy (NIRS) and indicator dilution theory, which realizes the hemodynamic parameters measured noninvasively. While the indocyanine green (ICG) was injected into human body, circulation carried the indicator mixing and diluting with the bloodstream. Then the near-nfrared probe was used to emit near-infrared light at 735, 805 and 940 nm wavelengths through the sufferer's fingertip and synchronously capture the transmission light containing the information of arterial pulse wave. By uploading the measured data, the computer would calculate the ICG concentration, establish continuous concentration curve and compute some intermediate variables such as the mean transmission time (MTT) and the initial blood ICG concentration (c(t0)). Accordingly Cardiac Output (CO) and Circulating Blood Volume (CBV) could be calculated. Compared with the clinical "gold standard" methods of thermodilution and I-131 isotope-labelling method to measure the two parameters by clinical controlled trials, ten sets of data were obtained. The maximum relative errors of this method were 8.88% and 4.28% respectively, and both of the average relative errors were below 5%. The result indicates that this method can meet the clinical accuracy requirement and can be used as a noninvasive, repeatable and applied solution for clinical hemodynamnic parameters measurement.

  17. Hemodynamic stroke: A rare pitfall in cranio cervical junction surgery

    Directory of Open Access Journals (Sweden)

    Jan Frederick Cornelius

    2014-01-01

    Full Text Available Surgical C1C2-stabilization may be complicated by arterial-arterial embolism or arterial injury. Another potential complication is hemodynamic stroke. The latter might be induced in patients with poor posterior fossa collateralization (risk factor 1 when the vertebral artery (VA is compressed during reduction (risk factor 2. We report a clinical case where this rare situation occurred: A 72-year old patient was undergoing C1C2-stabilization for subluxation due to rheumatoid arthritis. Preoperative computed tomography angiography (CTA had shown poor collaterals in the posterior fossa. Furthermore, intraoperative Doppler ultrasound (US detected unilateral VA occlusion during reduction. It appeared to be a high-risk situation for hemodynamic stroke. Surgical inspection of the VA found osteofibrous compressing elements. Arterial decompression was performed resulting in the normal flow as detected by US. Subsequently, C1C2-stabilization could be realized. The clinical and radiological outcome was very favorable. In C1C2-stabilization precise analysis of preoperative CTA and intraoperative US are important to detect risk factors of hemodynamic stroke. Using these data may prevent this rare, but potentially life-threatening complication.

  18. Comprehensive cognitive and cerebral hemodynamic evaluation after cranioplasty

    Directory of Open Access Journals (Sweden)

    Coelho F

    2014-05-01

    Full Text Available Fernanda Coelho,1 Arthur Maynart Oliveira,2 Wellingson Silva Paiva,2 Fabio Rios Freire,1 Vanessa Tome Calado,1 Robson Luis Amorim,2 Iuri Santana Neville,2 Almir Ferreira de Andrade,2 Edson Bor-Seng-Shu,3 Renato Anghinah,1 Manoel Jacobsen Teixeira21Neurorehabilitation Group, Division of Neurology, 2Division of Neurosurgery, 3Neurosonology and Cerebral Hemodynamics Group, University of São Paulo Medical School, São Paulo, BrazilAbstract: Decompressive craniectomy is an established procedure to lower intracranial pressure and can save patients' lives. However, this procedure is associated with delayed cognitive decline and cerebral hemodynamics complications. Studies show the benefits of cranioplasty beyond cosmetic aspects, including brain protection, and functional and cerebrovascular aspects, but a detailed description of the concrete changes following this procedure are lacking. In this paper, the authors report a patient with trephine syndrome who underwent cranioplasty; comprehensive cognitive and cerebral hemodynamic evaluations were performed prior to and following the cranioplasty. The discussion was based on a critical literature review.Keywords: cranioplasty, decompressive craniotomy, perfusion CT, traumatic brain injury, cognition, neuropsychological test

  19. Cerebral hemodynamics and baroreflex sensitivity after carotid artery stenting.

    Science.gov (United States)

    Hsu, L-C; Chang, F-C; Kuo, T B J; Wong, W-J; Hu, H-H

    2013-01-01

    The long-term hemodynamic effects of carotid angioplasty and stenting (CAS) are unclear. We performed a longitudinal study to investigate the variations in cerebral hemodynamics in patients undergoing CAS. We performed prospective evaluation of 63 symptomatic male patients (19 patients had transient ischemic attack and 44 had minor stroke; mean age: 77.3 ± 6.3 years [range: 51-86]). The mean blood flow velocities (MBFV) and pulsatility index (PI) of the middle cerebral arteries (MCA) on both sides were evaluated using transcranial color-coded Doppler (TCCD) ultrasonography. Cardiac autonomic activities were evaluated by measuring baroreflex sensitivity (BRS). All parameters were measured at baseline prior to CAS and at 1, 3, 6, and 12 months after CAS. The preoperative MBFV and PI of the ipsilateral MCA were significantly lower than those of the contralateral side. However, after CAS, MBFV in the ipsilateral MCA increased significantly until 2 weeks after stenting, after which the MBFV gradually decreased and remained stable for 1 year after CAS. Further, we observed a nonsignificant increase in MBFV in the contralateral MCA after CAS. In contrast to the MBFV, the BRS values decreased significantly 1 month after stenting and returned to baseline levels 6 months after CAS. Patients with CAS showed improved global cerebral hemodynamic status. However, the BRS did not normalize initially, and baseline value was achieved at 6 months after stenting. © 2012 John Wiley & Sons A/S.

  20. Vascular Adaptation to Exercise in Humans: Role of Hemodynamic Stimuli

    Science.gov (United States)

    Green, Daniel J.; Hopman, Maria T. E.; Padilla, Jaume; Laughlin, M. Harold; Thijssen, Dick H. J.

    2017-01-01

    On the 400th anniversary of Harvey's Lumleian lectures, this review focuses on “hemodynamic” forces associated with the movement of blood through arteries in humans and the functional and structural adaptations that result from repeated episodic exposure to such stimuli. The late 20th century discovery that endothelial cells modify arterial tone via paracrine transduction provoked studies exploring the direct mechanical effects of blood flow and pressure on vascular function and adaptation in vivo. In this review, we address the impact of distinct hemodynamic signals that occur in response to exercise, the interrelationships between these signals, the nature of the adaptive responses that manifest under different physiological conditions, and the implications for human health. Exercise modifies blood flow, luminal shear stress, arterial pressure, and tangential wall stress, all of which can transduce changes in arterial function, diameter, and wall thickness. There are important clinical implications of the adaptation that occurs as a consequence of repeated hemodynamic stimulation associated with exercise training in humans, including impacts on atherosclerotic risk in conduit arteries, the control of blood pressure in resistance vessels, oxygen delivery and diffusion, and microvascular health. Exercise training studies have demonstrated that direct hemodynamic impacts on the health of the artery wall contribute to the well-established decrease in cardiovascular risk attributed to physical activity. PMID:28151424

  1. A study of the hemodynamics of anterior communicating artery aneurysms

    Science.gov (United States)

    Cebral, Juan R.; Castro, Marcelo A.; Putman, Christopher M.

    2006-03-01

    In this study, the effects of unequal physiologic flow conditions in the internal carotid arteries on the intra-aneurysmal hemodynamics of anterior communicating artery aneurysms were investigated. Patient-specific vascular computational fluid dynamics models of five cerebral aneurysms were constructed from bilateral 3D rotational angiography images. The aneurysmal hemodynamics was analyzed under a range of physiologic flow conditions including the effects of unequal mean flows and phase shifts between the flow waveforms of the left and right internal carotid arteries. A total of five simulations were performed for each patient, and unsteady wall shear stress (WSS) maps were created for each flow condition. Time dependent curves of average WSS magnitude over selected regions on the aneurysms were constructed and used to analyze the influence of the inflow conditions. It was found that mean flow imbalances in the feeding vessels tend to shift the regions of elevated WSS (flow impingement region) towards the dominating inflow jet and to change the magnitude of the WSS peaks. However, the overall qualitative appearance of the WSS distribution and velocity simulations is not substantially affected. In contrast, phase differences tend to increase the temporal complexity of the hemodynamic patterns and to destabilize the intra-aneurysmal flow pattern. However, these effects are less important when the A1 confluence is less symmetric, i.e. dominated by one of the A1 segments. Conditions affecting the flow characteristics in the parent arteries of cerebral aneurysms with more than one avenue of inflow should be incorporated into flow models.

  2. Central and peripheral hemodynamics in exercising humans

    DEFF Research Database (Denmark)

    Calbet, J A L; González-Alonso, J; Helge, J W

    2015-01-01

    during incremental upright arm cranking (AC) and leg pedalling (LP) to exhaustion (Wmax) in nine males. Systemic VC, peak cardiac output (Qpeak) (indocyanine green) and stroke volume (SV) were 18%, 23%, and 20% lower during AC than LP. The mean BP, the rate-pressure product and the associated myocardial...

  3. Evaluation of the condylar movement on MRI during maximal mouth opening in patients with internal derangement of TMJ; comparison with transcranial view

    International Nuclear Information System (INIS)

    Cho, Bong Hae

    2001-01-01

    To evaluate the condylar movement at maximal mouth opening on MRI in patients with internal derangement. MR images and transcranial views for 102 TMJs in 51 patients were taken in closed and maximal opening positions, and the amount of condylar movement was analyzed annotatively and qualitatively. For MR images, the mean condylar movements were 9.4 mm horizontally, 4.6 mm vertically and 10.9 mm totally, while those for transcranial views were 12.5 mm, 4.6 mm, and 13.7 mm respectively. The condyle moved forward beyond the summit of the articular eminence in 41 TMJs (40.2%) for MR images than in transcranial views

  4. Role of Methylene Blue in the Maintenance of Postinduction Hemodynamic Status in Patients with Perforation Peritonitis: A Pilot Study.

    Science.gov (United States)

    Senthilnathan, Muthapillai; Cherian, Anusha; Balachander, Hemavathi; Maroju, Nanda Kishore

    2017-01-01

    Methylene blue is an inhibitor of guanylate cyclase and hence prevents vasoplegia mediated by nitric oxide in patients with sepsis. This study aimed to analyze the effect of methylene blue on blood pressure maintenance following induction of anesthesia in patients presenting with peritonitis. Thirty patients diagnosed to have perforation peritonitis were randomized into two groups (Group MB, Group NS). Patients in Group MB were given injection methylene blue 2 mg/kg over 20 min and patients in Group NS were given 50 ml of normal saline over 20 min, before induction. Heart rate, mean arterial pressure (MAP), cardiac output, and systemic vascular resistance (SVR) were recorded every 5 min for 1 h after infusion. Hemodynamic parameters were analyzed using repeated-measures analysis of variance with Bonferroni's test. Blood gas analysis was analyzed using independent Student's t -test, and P methylene blue were noted. Methylene blue contributes to the maintenance of postinduction hemodynamic stability in patients with perforation peritonitis.

  5. The effects of unilateral and bilateral spinal anaesthesia on hemodynamic parameters in patients surgically treated for inguinal hernia: Hemodynamic parameters and spinal anesthesia

    Directory of Open Access Journals (Sweden)

    Milosavljević Snežana

    2016-01-01

    Full Text Available Introduction: Conventional bilateral spinal anaesthesia is commonly used for surgical treatment of inguinal hernia because it causes fast development of block with relatively small dosage of local anaesthetic; furthermore, it is easily administered, reduces the level of metabolic response to stress, reduces the incidence of deep venous thrombosis and respiratory depression. On the other hand, the main side effect is hypotension Objective: The goal of the research was to determine which of the two methods of spinal anaesthesia (conventional bilateral, achieved with regular dosage of long-lasting bupivacaine or hypobaric unilateral, achieved with combined application of bupivacaine and fentanyl ensures higher hemodynamic stability during tension-free hernioplasty in patients from group I and II of ASA classification system. Methods: The research was conducted as a prospective, controlled clinical study with the total amount of 50 patients, males and females, and within the age span ranging from 17 to 77, who all had indications for surgical treatment of one-sided inguinal hernia under spinal anaesthesia. The hemodynamic parameters (heart rate, systolic, diastolic and mean arterial pressure were measured during following intervals: T1 - during preanaesthetic visit, T2 - after premedication and the iv administration of Ringer's lactate solution, T3 - 15 minutes after the administration of spinal anaesthesia, T4 - after the surgical incision, T5 - intraoperatively, T6 - during the placement of the last surgical stitch on the skin, T7 - one hour postoperatively. Results: The results showed that the frequency of clinically relevant hypotension was statistically much higher in patients with bilateral spinal anaesthesia (24 % when compared to patients administered with unilateral spinal anaesthesia (4%. Ten minutes after the application of spinal anaesthesia the mean arterial pressure has decreased by 20% when compared to basic values in group BB, and by

  6. Decomposition of Near-Infrared Spectroscopy Signals Using Oblique Subspace Projections: Applications in Brain Hemodynamic Monitoring

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    Alexander Caicedo

    2016-11-01

    Full Text Available Clinical data is comprised by a large number of synchronously collected biomedical signals that are measured at different locations. Deciphering the interrelationships of these signals can yield important information about their dependence providing some useful clinical diagnostic data. For instance, by computing the coupling between Near-Infrared Spectroscopy signals (NIRS and systemic variables the status of the hemodynamic regulation mechanisms can be assessed. In this paper we introduce an algorithm for the decomposition of NIRS signals into additive components. The algorithm, SIgnal DEcomposition base on Obliques Subspace Projections (SIDE-ObSP, assumes that the measured NIRS signal is a linear combination of the systemic measurements, following the linear regression model y = Ax + _. SIDE-ObSP decomposes the output such that, each component in the decomposition represents the sole linear influence of one corresponding regressor variable. This decomposition scheme aims at providing a better understanding of the relation between NIRS and systemic variables, and to provide a framework for the clinical interpretation of regression algorithms, thereby, facilitating their introduction into clinical practice. SIDE-ObSP combines oblique subspace projections (ObSP with the structure of a mean average system in order to define adequate signal subspaces. To guarantee smoothness in the estimated regression parameters, as observed in normal physiological processes, we impose a Tikhonov regularization using a matrix differential operator. We evaluate the performance of SIDE-ObSP by using a synthetic dataset, and present two case studies in the field of cerebral hemodynamics monitoring using NIRS. In addition, we compare the performance of this method with other system identification techniques. In the first case study data from 20 neonates during the first three days of life was used, here SIDE-ObSP decoupled the influence of changes in arterial oxygen

  7. Serum markers of deranged myocardial collagen turnover: their relation to malignant ventricular arrhythmias in cardioverter-defibrillator recipients with heart failure.

    Science.gov (United States)

    Flevari, Panayota; Theodorakis, George; Leftheriotis, Dionyssios; Kroupis, Christos; Kolokathis, Fotis; Dima, Kleanthi; Anastasiou-Nana, Maria; Kremastinos, Dimitrios

    2012-10-01

    Pathologic collagen remodeling has been involved in the occurrence of ventricular arrhythmias and sudden cardiac death in heart failure. The aim of the study was to investigate the relationship between malignant ventricular arrhythmias and cardiac collagen turnover indexes, expressing specific types of derangement in collagen physiology, in stable patients with an implantable cardioverter-defibrillator (ICD). Seventy-four patients with an ICD and heart failure were studied. They had coronary artery disease (n = 42) or dilated cardiomyopathy, New York Heart Association classes I and II, and left ventricular ejection fraction 29% ± 1%. An ICD had been implanted for secondary (n = 36) or primary prevention of sudden cardiac death. We assessed (1) markers of collagen types I and III synthesis and their ratio: procollagen type I carboxyterminal peptide (PICP), procollagen type III aminoterminal peptide (PIIINP), and PICP/PIIINP; (2) markers of collagen degradation, degradation inhibition, and their ratio: matrix metalloproteinase 9 (MMP-9), tissue inhibitor of matrix metalloproteinase (TIMP) 1 (TIMP-1), and MMP-9/TIMP-1. Patients were prospectively followed up for 1 year. The number of episodes necessitating appropriate interventions for ventricular tachyarrhythmias (>170 beat/min) was related to the assessed parameters. Multivariate analysis revealed a significant relation between the number of tachyarrhythmic episodes and MMP-9/TIMP-1 (P = .007), PICP/PIIINP (P = .007), and ejection fraction (P = .04). No other significant relation was observed between arrhythmias and the remaining parameters. In heart failure, biochemical markers indicative of a deranged equilirium in myocardial collagen deposition/degradation and collagen I/III synthesis are related to ventricular arrhythmogenesis. Further studies are needed to investigate their predictive ability. Copyright © 2012 Mosby, Inc. All rights reserved.

  8. Beneficial hemodynamic effects of nicorandil in a canine model of acute congestive heart failure: comparison with nitroglycerin and cromakalim.

    Science.gov (United States)

    Noguchi, K; Matsuzaki, T; Ojiri, Y; Koyama, T; Nakasone, J; Sakanashi, M

    1998-01-01

    Comparative hemodynamic effects of nicorandil (NCR), nitroglycerin (NTG) and cromakalim (CRM) were examined in a canine model of acute congestive heart failure (CHF). CHF was produced by injections of saponin into coronary arteries of anesthetized dogs followed by volume loading and continuous i.v. infusion of methoxamine. After the treatment, aortic blood flow (AoF), left ventricular dP/dt and myocardial segment shortening (SS) markedly decreased, while the left ventricular end-diastolic pressure (LVEDP), the right atrial pressure (RAP) and the systemic vascular resistance (SVR) increased. NCR (n = 6), NTG (n = 6) and CRM (n = 8), which were administered i.v. after production of CHF, caused a comparable reduction in LVEDP. NCR and CRM profoundly increased AoF and SS but NTG did only slightly. On the other hand, NTG and NCR but not CRM significantly reduced RAP. Intracoronary NCR (n = 8) exerted no or similar effects on SS as well as systemic hemodynamic indices to those observed with i.v. NCR despite distinct coronary vasodilation. These results indicate that NCR may exert beneficial hemodynamic effects in an experimental CHF mainly due to lessening both afterload and preload rather than the coronary vasodilating effect.

  9. A clinical prediction model to identify patients at high risk of hemodynamic instability in the pediatric intensive care unit.

    Science.gov (United States)

    Potes, Cristhian; Conroy, Bryan; Xu-Wilson, Minnan; Newth, Christopher; Inwald, David; Frassica, Joseph

    2017-11-20

    Early recognition and timely intervention are critical steps for the successful management of shock. The objective of this study was to develop a model to predict requirement for hemodynamic intervention in the pediatric intensive care unit (PICU); thus, clinicians can direct their care to patients likely to benefit from interventions to prevent further deterioration. The model proposed in this study was trained on a retrospective cohort of all patients admitted to a tertiary PICU at a single center in the United States, and validated on another retrospective cohort of all patients admitted to the PICU at a single center in the United Kingdom. The PICU clinical information system database (Intellivue Clinical Information Portfolio, Philips, UK) was interrogated to collect physiological and laboratory data. The model was trained using a variant of AdaBoost, which learned a set of low-dimensional classifiers, each of which was age adjusted. A total of 7052 patients admitted to the US PICU was used for training the model, and a total of 970 patients admitted to the UK PICU was used for validation. On the training/validation datasets, the model showed better prediction of hemodynamic intervention (area under the receiver operating characteristic (AUROC) = 0.81/0.81) than systolic blood pressure-based (AUCROC = 0.58/0.67) or shock index-based (AUCROC = 0.63/0.65) models. Both of these models were age adjusted using the same classifier. The proposed model reliably predicted the need for hemodynamic intervention in PICU patients and provides better classification performance when compared to systolic blood pressure-based or shock index-based models alone. This model could readily be built into a clinical information system to identify patients at risk of hemodynamic instability.

  10. Impact of the postpump resistance on pressure-flow waveform and hemodynamic energy level in a neonatal pulsatile centrifugal pump.

    Science.gov (United States)

    Wang, Shigang; Haines, Nikkole; Richardson, J Scott; Dasse, Kurt A; Undar, Akif

    2009-01-01

    This study tested the impact of different postpump resistances on pulsatile pressure-flow waveforms and hemodynamic energy output in a mock extracorporeal system. The circuit was primed with a 40% glycerin-water mixture, and a PediVAS centrifugal pump was used. The pre- and postpump pressures and flow rates were monitored via a data acquisition system. The postpump resistance was adjusted using a Hoffman clamp at the outlet of the pump. Five different postpump resistances and rotational speeds were tested with nonpulsatile (NP: 5000 RPM) and pulsatile (P: 4000 RPM) modes. No backflow was found when using pulsatile flow. With isoresistance, increased arterial resistances decreased pump flow rates (NP: from 1,912 ml/min to 373 ml/min; P: from 1,485 ml/min to 288 ml/min), increased postpump pressures (NP: from 333 mm Hg to 402 mm Hg; P: from 223 mm Hg to 274 mm Hg), and increased hemodynamic energy output with pulsatile mode. Pump flow rate correlated linearly with rotational speed (RPMs) of the pump, whereas postpump pressures and hemodynamic energy outputs showed curvilinear relationships with RPMs. The maximal pump flow rate also increased from 618 ml/min to 4,293 ml/min with pulsatile mode and from 581 ml/min to 5,665 ml/min with nonpulsatile mode. Results showed that higher postpump resistance reduced the pump flow range, and increased postpump pressure and surplus hemodynamic energy output with pulsatile mode. Higher rotational speeds also generated higher pump flow rates, postpump pressures, and increased pulsatility.

  11. [Isotopic study of cardiac hemodynamics after multiple valve prothesis (author's transl)].

    Science.gov (United States)

    Schicha, H; Becker, V; Both, A; Lösse, B; Krian, A; Feinendegen, L E

    1977-08-01

    The radiocardiography of the minimal transit times (MTTs) produces cardiologically useful hemodynamic data also in such instances where invasive techniques with the cardiac catheter are technically difficult, as is the case in patients with multiple valve prothesis. The present study reports on MTT measurements in 9 patients with tricuspidal prothesis, 8 of which had additional mitralvalve prothesis and 2 additional aortic valve prothesis. The measurements were made with Tc-99m Pertechnetate, and an Anger camera with electronic data processing was used as detector system. The results indicate that following implantation of valve prothesis the hemodynamic state remained essentially disturbed. The pathologically altered transit times are an expression of disturbed volume ratios. The transit times in the atria remained prolonged by an average factor of 4-5. The ejection of the left ventricle stayed diminished more pronounced than on the right. The values of one patient who was examined before and after implantation of the prothesis in mitral and tricuspidal position, also showed a worsening of the data especially in the atria. Because the cardiac function study with radioisotopes is non invasive, simple, and fast, and leads to only a minor radiation burden, the method may be repeated and without hazard used for control follow-ups.

  12. Label-free determination of hemodynamic parameters in the microcirculaton with third harmonic generation microscopy.

    Directory of Open Access Journals (Sweden)

    Steffen Dietzel

    Full Text Available Determination of blood flow velocity and related hemodynamic parameters is an important aspect of physiological studies which in many settings requires fluorescent labeling. Here we show that Third Harmonic Generation (THG microscopy is a suitable tool for label-free intravital investigations of the microcirculation in widely-used physiological model systems. THG microscopy is a non-fluorescent multi-photon scanning technique combining the advantages of label-free imaging with restriction of signal generation to a focal spot. Blood flow was visualized and its velocity was measured in adult mouse cremaster muscle vessels, non-invasively in mouse ear vessels and in Xenopus tadpoles. In arterioles, THG line scanning allowed determination of the flow pulse velocity curve and hence the heart rate. By relocating the scan line we obtained velocity profiles through vessel diameters, allowing shear rate calculations. The cell free layer containing the glycocalyx was also visualized. Comparison of the current microscopic resolution with theoretical, diffraction limited resolution let us conclude that an about sixty-fold THG signal intensity increase may be possible with future improved optics, optimized for 1200-1300 nm excitation. THG microscopy is compatible with simultaneous two-photon excited fluorescence detection. It thus also provides the opportunity to determine important hemodynamic parameters in parallel to common fluorescent observations without additional label.

  13. Time-Frequency Characterization of Cerebral Hemodynamics of Migraine Sufferers as Assessed by NIRS Signals

    Directory of Open Access Journals (Sweden)

    Filippo Molinari

    2010-01-01

    Full Text Available Near-infrared spectroscopy (NIRS is a noninvasive system for the real-time monitoring of the concentration of oxygenated (O2Hb and reduced (HHb hemoglobin in the brain cortex. O2Hb and HHb concentrations vary in response to cerebral autoregulation. Sixty-eight women (14 migraineurs without aura, 49 migraineurs with aura, and 5 controls performed breath-holding and hyperventilation during NIRS recordings. Signals were processed using the Choi-Williams time-frequency transform in order to measure the power variation of the very-low frequencies (VLF: 20–40 mHz and of the low frequencies (LF: 40–140 mHz. Results showed that migraineurs without aura present different LF and VLF power levels than controls and migraineurs with aura. The accurate power measurement of the time-frequency analysis allowed for the discrimination of the subjects' hemodynamic patterns. The time-frequency analysis of NIRS signals can be used in clinical practice to assess cerebral hemodynamics.

  14. Time-Frequency Characterization of Cerebral Hemodynamics of Migraine Sufferers as Assessed by NIRS Signals

    Directory of Open Access Journals (Sweden)

    Liboni William

    2010-01-01

    Full Text Available Abstract Near-infrared spectroscopy (NIRS is a noninvasive system for the real-time monitoring of the concentration of oxygenated ( and reduced (HHb hemoglobin in the brain cortex. and HHb concentrations vary in response to cerebral autoregulation. Sixty-eight women (14 migraineurs without aura, 49 migraineurs with aura, and 5 controls performed breath-holding and hyperventilation during NIRS recordings. Signals were processed using the Choi-Williams time-frequency transform in order to measure the power variation of the very-low frequencies (VLF: 20–40 mHz and of the low frequencies (LF: 40–140 mHz. Results showed that migraineurs without aura present different LF and VLF power levels than controls and migraineurs with aura. The accurate power measurement of the time-frequency analysis allowed for the discrimination of the subjects' hemodynamic patterns. The time-frequency analysis of NIRS signals can be used in clinical practice to assess cerebral hemodynamics.

  15. The effect of low-dose oxytocin infusion on cerebral hemodynamics in pregnant women.

    Science.gov (United States)

    van Veen, Teelkien R; Belfort, Michael A; Zeeman, Gerda G

    2011-08-01

    We investigated the cerebrovascular effects of continuous infusion of low-dose oxytocin in normal pregnant women undergoing induction of labor. In our prospective observational study, middle cerebral artery velocity was measured with transcranial Doppler ultrasound in 25 healthy, normotensive, nonsmoking patients undergoing induction of labor. No vasoactive drugs were used before or during the study period. Measurements were made at baseline and 15, 30, 60, and 120 minutes after oxytocin initiation. Mean arterial pressure, cerebral perfusion pressure, resistance index, resistance area product, and cerebral flow index at different times were calculated and compared using one-way analysis of variance (ANOVA) for repeated measures or Friedman repeated-measures ANOVA as appropriate, with P<0.05 regarded as significant. No significant systemic or cerebrovascular changes were noted after oxytocin initiation, and there was no correlation between the dosage administered and any hemodynamic parameter. Induction-dose oxytocin does not significantly affect selected cerebral hemodynamic parameters in the first 2 hours after initiation. © Thieme Medical Publishers.

  16. Hemodynamic properties and arterial structure in male rat offspring with fetal hypothyroidism.

    Science.gov (United States)

    Ghanbari, Mahboubeh; Bagheripuor, Fatemeh; Piryaei, Abbas; Zahediasl, Saleh; Noroozzadeh, Mahsa; Ghasemi, Asghar

    2016-10-01

    Thyroid hormones (THs) play a crucial role in the development of different systems during fetal life; fetal hypothyroidism (FH) is associated with reduced cardiac function and dimensions in neonates. The aim of this study is to determine whether TH deficiency during fetal life is associated with arterial structural and hemodynamic changes during adulthood. Hypothyroidism was induced by adding 0.025% 6-propyl-2-thiouracil in drinking water throughout pregnancy, while controls consumed only tap water. Hemodynamic parameters, cross-sectional area, intima-media thickness (IMT), and density of nuclei of smooth muscle cells and endothelial cells (ECs) in the aorta and mesenteric arteries were measured. Compared to controls, in the FH group, baseline systolic blood pressure (105.7 ± 3.1 vs. 87.9 ± 3.3 mm Hg, p < 0.01), diastolic blood pressure (64.4 ± 1.7 vs. 53.2 ± 2.1 mm Hg, p < 0.05), and mean arterial pressure (80.9 ± 2.1 vs. 67.1 ± 2.1 mm Hg, p < 0.01) were significantly lower. In addition, in the FH group, intensity and latency of response to phenylephrine were significantly lower and longer, respectively, as were the IMT and density of ECs in the aorta and superior mesenteric arteries. In conclusion, this study showed that TH deficiency during fetal life can have long-lasting functional and histological effects, which can compromise cardiovascular function during adulthood.

  17. The hemodynamic effects of methylene blue when administered at the onset of cardiopulmonary bypass.

    Science.gov (United States)

    Maslow, Andrew D; Stearns, Gary; Butala, Parag; Batula, Parag; Schwartz, Carl S; Gough, Jeffrey; Singh, Arun K

    2006-07-01

    Hypotension occurs during cardiopulmonary bypass (CPB), in part because of induction of the inflammatory response, for which nitric oxide and guanylate cyclase play a central role. In this study we examined the hemodynamic effects of methylene blue (MB), an inhibitor of guanylate cyclase, administered during cardiopulmonary bypass (CPB) to patients taking angiotensin-converting enzyme inhibitors. Thirty patients undergoing cardiac surgery were randomized to receive either MB (3 mg/kg) or saline (S) after institution of CPB and cardioplegic arrest. CPB was managed similarly for all study patients. Hemodynamic data were assessed before, during, and after CPB. The use of vasopressors was recorded. All study patients experienced a similar reduction in mean arterial blood pressure (MAP) and systemic vascular resistance (SVR) with the onset of CPB and cardioplegic arrest. MB increased MAP and SVR and this effect lasted for 40 minutes. The saline group demonstrated a persistently reduced MAP and SVR throughout CPB. The saline group received phenylephrine more frequently during CPB, and more norepinephrine after CPB to maintain a desirable MAP. The MB group recorded significantly lower serum lactate levels despite equal or greater MAP and SVR. In conclusion, administration of MB after institution of CPB for patients taking angiotensin-converting enzyme inhibitors increased MAP and SVR and reduced the need for vasopressors. Furthermore, serum lactate levels were lower in MB patients, suggesting more favorable tissue perfusion.

  18. Hemodynamic effects of 6% hydroxyethyl starch infusion in sevoflurane-anesthetized thoroughbred horses.

    Science.gov (United States)

    Ohta, Minoru; Kurimoto, Shinjiro; Tokushige, Hirotaka; Kuroda, Taisuke; Ishikawa, Yuhiro

    2013-07-31

    To determine hemodynamic effects of hydroxyethyl starch (HES) infusion during anesthesia in horses, incremental doses of 6% HES were administered to 6 healthy Thoroughbred horses. Anesthesia was induced with xylazine, guaifenesin and thiopental and maintained with sevoflurane at 2.8% of end-tidal concentration in all horses. The horses were positioned in right lateral recumbency and administered 3 intravenous dose of 6% HES (5 ml/kg) over 15 min with 15-min intervals in addition to constant infusion of lactated Ringer's solution at 10 ml/kg/hr. Hemodynamic parameters were measured before and every 15 min until 90 min after the administration of 6% HES. There was no significant change in heart rate and arterial blood pressures throughout the experiment. The HES administration produced significant increases in mean right atrial pressure, stroke volume, cardiac output (CO) and decrease in systemic vascular resistance (SVR) in a dose-dependent manner. There was no significant change in electrolytes (Na(+), K(+), Cl(-)) throughout the experiment, however, packed cell volume, hemoglobin concentration, and total protein and albumin concentrations decreased in a dose-dependent manner following the HES administration. In conclusion, the HES administration provides a dose-dependent increase in CO, but has no impact upon arterial blood pressures due to a simultaneous decrease in SVR.

  19. Supply and usage of hemodynamic services in the state of Rio de Janeiro, Brazil.

    Science.gov (United States)

    Andreazzi, Maria de Fatima Siliansky de; Andreazzi, Marco Antonio Ratzsch de; Sancho, Leyla; Freitas, Heitor Alarico Gonçalves de

    2014-01-01

    To analyze the supply of equipment and procedures inherent to public hemodynamic services in the State of Rio de Janeiro, Brazil. We conducted an exploratory study based on official data banks: AMS survey of IBGE, CNES, AIH and APAC, and ANS. The examination period of the supply was from 1999 to 2009, and of the use, from 2008 to October 2012. Since 1999 there has been a growth in the acquisition of hemodynamic equipment. The private sector concentrates most of the offer, but has been reducing its availability to the Unified Health System (SUS). The ratio of the equipment and the population exceeds that of some rich countries. On the supply side, there was, in Rio de Janeiro, in 2009, a rate of 4.1 units per million inhabitants, higher than in Brazil as a whole, of 3.4; however, when considering only the offer for the SUS (SUS), the values are similar, 1.6 and 1.5. The procedures of interventional cardiology grew between 2008 and 2011 in Rio de Janeiro, but the majority of public hospitals have reduced production and the private have increased it, resulting in the referral of SUS users to be submitted to procedures great distances from home.

  20. [Acute perioperative hemodilution without using hydroxyethyl starch : hemodynamic alterations under "controlled" hypovolemia].

    Science.gov (United States)

    Hofmann-Kiefer, K; Chappell, D; Jacob, M; Schülke, A; Helfen, T; Anetzberger, J; Rehm, M

    2015-01-01

    Up to now hydroxyethyl starch preparations have frequently been used to compensate for volume deficits accompanying blood withdrawal during acute normovolemic hemodilution. This approach was questioned with respect to the current limitations for use of hydroxyethyl starch solutions imposed by the European Medicines Agency. Because crystalloids distribute evenly across the whole extracellular compartment, 80 % of the infused solution will be "lost" to the interstitial space. Thus, a physiological adjustment of blood loss caused by hemodilution with crystalloids alone (1:5 ratio) seems hardly feasible and according to current data perhaps not even desirable. A 3:1 ratio (crystalloids versus blood loss) as applied in the current study can be regarded as a practical compromise between physiological needs and recommendations according to the literature (1.4:1) but will lead to moderate hypovolemia the hemodynamic consequences of which are not well described. The current study investigates the hemodynamic impact of a hemodilution with crystalloids under the precondition of a 3:1 substitution ratio compared to withdrawn blood. In the context of acute perioperative hemodilution 10 otherwise healthy women graded I and II on the American Society of Anesthesiologists (ASA) classification scheduled for open gynecological cancer surgery underwent an average blood withdrawal of 1097 ± 285 ml which was substituted by an average of 3430 ± 806 ml of Ringer's lactate. The resulting deficit in blood volume was exactly quantified by a double tracer technique. Hemodynamic changes were evaluated by a combination of thermodilution and pulse contour analysis (PiCCO system®). Subsequently, the remaining volume deficit was compensated by 245 ± 64 ml of a 20 % albumin solution and hemodynamic parameters were again evaluated. When infusing Ringer's lactate in a 3:1 ratio compared to the actual blood loss, the blood volume decreased by 12 %. The volume effect of Ringer

  1. High frequency oscillations in brain hemodynamic response

    Science.gov (United States)

    Akin, Ata; Bolay, Hayrunnisa

    2007-07-01

    Tight autoregulation of vessel tone guarantees proper delivery of nutrients to the tissues. This regulation is maintained at a more delicate level in the brain since any decrease in the supply of glucose and oxygen to neuronal tissues might lead to unrecoverable injury. Functional near infrared spectroscopy has been proposed as a new tool to monitor the cerebrovascular response during cognitive activity. We have observed that during a Stroop task three distinct oscillatory patterns govern the control of the cerebrovascular reactivity: very low frequency (0.02-0.05 Hz), low frequency (0.08-0.12 Hz) and high frequency (0.12-0.18 Hz). High frequency oscillations have been shown to be related to stress level of the subjects. Our findings indicate that as the stress level is increased so does the energy of the high frequency component indicating a higher stimulation from the autonomic nervous system.

  2. Toward Intelligent Hemodynamic Monitoring: A Functional Approach

    Directory of Open Access Journals (Sweden)

    Pierre Squara

    2012-01-01

    Full Text Available Technology is now available to allow a complete haemodynamic analysis; however this is only used in a small proportion of patients and seems to occur when the medical staff have the time and inclination. As a result of this, significant delays occur between an event, its diagnosis and therefore, any treatment required. We can speculate that we should be able to collect enough real time information to make a complete, real time, haemodynamic diagnosis in all critically ill patients. This article advocates for “intelligent haemodynamic monitoring”. Following the steps of a functional analysis, we answered six basic questions. (1 What is the actual best theoretical model for describing haemodynamic disorders? (2 What are the needed and necessary input/output data for describing this model? (3 What are the specific quality criteria and tolerances for collecting each input variable? (4 Based on these criteria, what are the validated available technologies for monitoring each input variable, continuously, real time, and if possible non-invasively? (5 How can we integrate all the needed reliably monitored input variables into the same system for continuously describing the global haemodynamic model? (6 Is it possible to implement this global model into intelligent programs that are able to differentiate clinically relevant changes as opposed to artificial changes and to display intelligent messages and/or diagnoses?

  3. [Current status of noninvasive hemodynamics in hypertension].

    Science.gov (United States)

    Waisman, G

    Hypertension is a haemodynamic disorder resulting from a persistent mismatch between cardiac output and peripheral resistance. Hypertension undergoes haemodynamic progression during its natural history. Impedance cardiography is a method of evaluating the cardiovascular system that obtains haemodynamic information from beat to beat through the analysis of variations in the impedance of the thorax on the passage of an electric current. Impedance cardiography unmasks the haemodynamic deterioration underlying the increase in blood pressure as age and systolic blood pressure increases. This method may help to improve blood pressure control through individualized treatment with reduction of peripheral resistance, maintenance of cardiac output or its increase, improvement of arterial compliance and preservation of organ-tissue perfusion. It is useful in the management of patients with resistant hypertension, since a greater percentage of patients controlled with changes in the treatment in relation to the haemodynamic measurements are obtained. Impedance cardiography is important and has prognostic utility in relation to a haemodynamic deterioration pattern and increased cardiovascular events. Copyright © 2017 SEH-LELHA. Publicado por Elsevier España, S.L.U. All rights reserved.

  4. Comparison of hemodynamics during hyperthermal immersion and exercise testing in apparently healthy females aged 50-60 years.

    Science.gov (United States)

    Lietava, Jan; Vohnout, Branislav; Valent, Denis; Celko, Juraj

    2004-07-01

    Owing to excessive worries regarding adverse cardiac events, hyperthermal balneotherapy for patients with coronary artery disease is underprescribed. However, very few cardiac events occur in similar heat stress during Finnish sauna bathing. Exercise testing has proven to be a safe diagnostic procedure even in survivors of myocardial infarction. We compared the effects of hyperthermal immersion and exercise testing on cardiac hemodynamics in 21 apparently healthy women aged 50-60 years. The maximal symptom-limited bicycle exercise test was performed according to the modified protocol of Wasserman. Hyperthermal immersion was carried out in 40 degrees C water and was completed by increasing the core temperature by about 2 degrees C. The left ventricular function was evaluated using continuous measurement of thoracic electric bioimpedance during both tests. The blood pressure, index of contractility and heart rate were measured directly, whereas the cardiac index, left cardiac work index and systemic vascular resistance index were calculated. The hemodynamic response, as assessed at continuous non-invasive monitoring, showed substantial differences between hyperthermal immersion and exercise testing. Overall, we found a significantly lower hemodynamic load during hyperthermal immersion in comparison with exercise testing. Entering the bath, there was a significant decrease in the left cardiac work, contractility and blood pressure. We recorded a slight increase in the heart rate towards peak hyperthermal immersion. However, other modulators such as the mean arterial pressure, index of contractility, cardiac index and left cardiac work index decreased even below resting values. Excessive hyperthermal immersion induced a lower hemodynamic load in apparently healthy women than standard maximal exercise testing.

  5. [Effects of two methods of heat therapy on the acute vascular response and hemodynamics in healthy subjects].

    Science.gov (United States)

    Ramírez-Vélez, R; García Sánchez, A; Martínez Betancourt, C J; Parra Galeano, C A; Ortega, J G; López Alban, C A; Agredo Zúñiga, R A

    2012-01-01

    Recently, non-pharmacological resources to relieve pain like hot packs and ultrasound (US) have become common in clinical practice. However, little experimental evidence is available about the possible mechanisms through which these methods bring about pain relief. We aimed to determine the effects of hot packs and US on the acute vascular response and on hemodynamic parameters in healthy subjects. We conducted an experimental study in 20 healthy subjects (10 men and 10 women; mean age, 22.54±1.70 years). The two interventions were randomly applied: a) hot packs (n=10): 15min at 60°C and b) US (n=10): 15min at 1Mhz. Before and after each intervention, the following vascular parameters were measured in the brachial artery using Doppler ultrasonography with a 7MHz probe: arterial compliance, elastic modulus, beta stiffness index, systolic and diastolic arterial diameters, systolic flow velocity and diastolic flow velocity, systolic/diastolic ratio, resistance index, and pulsatility index. The following hemodynamic parameters were monitored: heart rate and blood pressure (systolic, diastolic, and mean). After the application of hot packs, we observed changes in diastolic flow velocity and in the pulsatility index (Phot packs or US modifies the physiology of the vascular system but does not affect hemodynamic parameters in healthy subjects. Copyright © 2011 SERAM. Published by Elsevier Espana. All rights reserved.

  6. Hemodynamic Effects of Phenylephrine, Vasopressin, and Epinephrine in Children With Pulmonary Hypertension: A Pilot Study.

    Science.gov (United States)

    Siehr, Stephanie L; Feinstein, Jeffrey A; Yang, Weiguang; Peng, Lynn F; Ogawa, Michelle T; Ramamoorthy, Chandra

    2016-05-01

    During a pulmonary hypertensive crisis, the marked increase in pulmonary vascular resistance can result in acute right ventricular failure and death. Currently, there are no therapeutic guidelines for managing an acute crisis. This pilot study examined the hemodynamic effects of phenylephrine, arginine vasopressin, and epinephrine in pediatric patients with pulmonary hypertension. In this prospective, open-label, nonrandomized pilot study, we enrolled pediatric patients previously diagnosed with pulmonary hypertensive who were scheduled electively for cardiac catheterization. Primary outcome was a change in the ratio of pulmonary-to-systemic vascular resistance. Baseline hemodynamic data were collected before and after the study drug was administered. Eleven of 15 participants were women, median age was 9.2 years (range, 1.7-14.9 yr), and median weight was 26.8 kg (range, 8.5-55.2 kg). Baseline mean pulmonary artery pressure was 49 ± 19 mm Hg, and mean indexed pulmonary vascular resistance was 10 ± 5.4 Wood units. Etiology of pulmonary hypertensive varied, and all were on systemic pulmonary hypertensive medications. Patients 1-5 received phenylephrine 1 μg/kg; patients 6-10 received arginine vasopressin 0.03 U/kg; and patients 11-15 received epinephrine 1 μg/kg. Hemodynamics was measured continuously for up to 10 minutes following study drug administration. After study drug administration, the ratio of pulmonary-to-systemic vascular resistance decreased in three of five patients receiving phenylephrine, five of five patients receiving arginine vasopressin, and three of five patients receiving epinephrine. Although all three medications resulted in an increase in aortic pressure, only arginine vasopressin consistently resulted in a decrease in the ratio of systolic pulmonary artery-to-aortic pressure. This prospective pilot study of phenylephrine, arginine vasopressin, and epinephrine in pediatric patients with pulmonary hypertensive showed an increase in aortic

  7. Multiparametric estimation of brain hemodynamics with MR fingerprinting ASL.

    Science.gov (United States)

    Su, Pan; Mao, Deng; Liu, Peiying; Li, Yang; Pinho, Marco C; Welch, Babu G; Lu, Hanzhang

    2017-11-01

    Assessment of brain hemodynamics without exogenous contrast agents is of increasing importance in clinical applications. This study aims to develop an MR perfusion technique that can provide noncontrast and multiparametric estimation of hemodynamic markers. We devised an arterial spin labeling (ASL) method based on the principle of MR fingerprinting (MRF), referred to as MRF-ASL. By taking advantage of the rich information contained in MRF sequence, up to seven hemodynamic parameters can be estimated concomitantly. Feasibility demonstration, flip angle optimization, comparison with Look-Locker ASL, reproducibility test, sensitivity to hypercapnia challenge, and initial clinical application in an intracranial steno-occlusive process, Moyamoya disease, were performed to evaluate this technique. Magnetic resonance fingerprinting ASL provided estimation of up to seven parameters, including B1+, tissue T 1 , cerebral blood flow (CBF), tissue bolus arrival time (BAT), pass-through arterial BAT, pass-through blood volume, and pass-through blood travel time. Coefficients of variation of the estimated parameters ranged from 0.2 to 9.6%. Hypercapnia resulted in an increase in CBF by 57.7%, and a decrease in BAT by 13.7 and 24.8% in tissue and vessels, respectively. Patients with Moyamoya disease showed diminished CBF and lengthened BAT that could not be detected with regular ASL. Magnetic resonance fingerprinting ASL is a promising technique for noncontrast, multiparametric perfusion assessment. Magn Reson Med 78:1812-1823, 2017. © 2016 International Society for Magnetic Resonance in Medicine. © 2016 International Society for Magnetic Resonance in Medicine.

  8. Diagnosis of hemodynamic compromise in patients with chronic cerebral ischemia

    International Nuclear Information System (INIS)

    Kuroda, Satoshi; Sakuragi, Mitsugi; Motomiya, Mineo; Nakagawa, Tango; Mitsumori, Kenji; Tsuru, Mitsuo; Takigawa, Shugo; Kamiyama, Hiroyasu; Abe, Hiroshi.

    1990-01-01

    To evaluate the efficacy of tests for selecting patients with hemodynamic compromise, measurement of cerebral blood volume (CBV) with 99m Tc-RBC single photon emission computed tomography (SPECT) was performed in thirteen patients with occlusive cerebrovascular disease, and was compared with results obtained by 133 Xe SPECT and acetazolamide (Diamox) test. All patients in our study suffered TIA, RIND, or minor completed stroke. Cerebral angiography demonstrated severe stenosis or occlusion in the ipsilateral internal carotid artery or middle cerebral artery, although plain CT scan or MRI revealed no or, if any, only localized infarcted lesions. Regional cerebral blood volume (rCBV) was measured with 99m Tc-RBC SPECT and regional cerebral blood flow (rCBF) was measured with 133 Xe SPECT before and after intravenous injection of 10 - 12 mg/kg acetazolamide (Diamox). Our results suggest that the ipsilateral rCBV/rCBF (mean transit time) is a more sensitive index of the cerebral perfusion reserve than the use of only rCBV or rCBF of the ipsilateral hemisphere. Also, the ipsilateral rCBV/rCBF is significantly correlated (r= -0.72) with the Diamox reactivity of rCBF, which is considered to represent the cerebral vasodilatory capacity in patients with chronic cerebral ischemia. Postoperative SPECT study revealed remarkable improvement of ipsilateral rCBV/rCBF and Diamox reactivity in four patients who underwent EC/IC bypass surgery to improve the hemodynamic compromise. In conclusion, our results suggest that the measurement of rCBV/rCBF with 133 Xe SPECT and 99m Tc-RBC SPECT is useful for detecting the hemodynamic compromise in patients with occlusive cerebrovascular disease. (author)

  9. Optical imaging of neural and hemodynamic brain activity

    Science.gov (United States)

    Schei, Jennifer Lynn

    Optical imaging technologies can be used to record neural and hemodynamic activity. Neural activity elicits physiological changes that alter the optical tissue properties. Specifically, changes in polarized light are concomitant with neural depolarization. We measured polarization changes from an isolated lobster nerve during action potential propagation using both reflected and transmitted light. In transmission mode, polarization changes were largest throughout the center of the nerve, suggesting that most of the optical signal arose from the inner nerve bundle. In reflection mode, polarization changes were largest near the edges, suggesting that most of the optical signal arose from the outer sheath. To overcome irregular cell orientation found in the brain, we measured polarization changes from a nerve tied in a knot. Our results show that neural activation produces polarization changes that can be imaged even without regular cell orientations. Neural activation expends energy resources and elicits metabolic delivery through blood vessel dilation, increasing blood flow and volume. We used spectroscopic imaging techniques combined with electrophysiological measurements to record evoked neural and hemodynamic responses from the auditory cortex of the rat. By using implantable optics, we measured responses across natural wake and sleep states, as well as responses following different amounts of sleep deprivation. During quiet sleep, evoked metabolic responses were larger compared to wake, perhaps because blood vessels were more compliant. When animals were sleep deprived, evoked hemodynamic responses were smaller following longer periods of deprivation. These results suggest that prolonged neural activity through sleep deprivation may diminish vascular compliance as indicated by the blunted vascular response. Subsequent sleep may allow vessels to relax, restoring their ability to deliver blood. These results also suggest that severe sleep deprivation or chronic

  10. Predicting ICU hemodynamic instability using continuous multiparameter trends.

    Science.gov (United States)

    Cao, Hanqing; Eshelman, Larry; Chbat, Nicolas; Nielsen, Larry; Gross, Brian; Saeed, Mohammed

    2008-01-01

    Identifying hemodynamically unstable patients in a timely fashion in intensive care units (ICUs) is crucial because it can lead to earlier interventions and thus to potentially better patient outcomes. Current alert algorithms are typically limited to detecting dangerous conditions only after they have occurred and suffer from high false alert rates. Our objective was to predict hemodynamic instability at least two hours before a major clinical intervention (e.g., vasopressor administration), while maintaining a low false alert rate. From the MIMIC II database, containing ICU minute-by-minute heart rate (HR) and invasive arterial blood pressure (BP) monitoring trend data collected between 2001 and 2005, we identified 132 stable and 104 unstable patients that met our stability-instability criteria and had sufficient data points. We first derived additional physiological parameters of shock index, rate pressure product, heart rate variability, and two measures of trending based on HR and BP. Then we developed 220 statistical features and systematically selected a small set to use for classification. We applied multi-variable logistic regression modeling to do classification and implemented validation via bootstrapping. Area under receiver-operating curve (ROC) 0.83+/-0.03, sensitivity 0.75+/-0.06, and specificity 0.80+/-0.07; if the specificity is targeted at 0.90, then the sensitivity is 0.57+/-0.07. Based on our preliminary results, we conclude that the algorithms we developed using HR and BP trend data may provide a promising perspective toward reliable predictive alerts for hemodynamically unstable patients.

  11. Closure technique after carotid endarterectomy influences local hemodynamics.

    Science.gov (United States)

    Harrison, Gareth J; How, Thien V; Poole, Robert J; Brennan, John A; Naik, Jagjeeth B; Vallabhaneni, S Rao; Fisher, Robert K

    2014-08-01

    Meta-analysis supports patch angioplasty after carotid endarterectomy (CEA); however, studies indicate considerable variation in practice. The hemodynamic effect of a patch is unclear and this study attempted to elucidate this and guide patch width selection. Four groups were selected: healthy volunteers and patients undergoing CEA with primary closure, trimmed patch (5 mm), or 8-mm patch angioplasty. Computer-generated three-dimensional models of carotid bifurcations were produced from transverse ultrasound images recorded at 1-mm intervals. Rapid prototyping generated models for flow visualization studies. Computational fluid dynamic studies were performed for each model and validated by flow visualization. Mean wall shear stress (WSS) and oscillatory shear index (OSI) maps were created for each model using pulsatile inflow at 300 mL/min. WSS of OSI >0.3 were considered pathological, predisposing to accretion of intimal hyperplasia. The resultant WSS and OSI maps were compared. The four groups comprised 8 normal carotid arteries, 6 primary closures, 6 trimmed patches, and seven 8-mm patches. Flow visualization identified flow separation and recirculation at the bifurcation increased with a patch and was related to the patch width. Computational fluid dynamic identified that primary closure had the fewest areas of low WSS or elevated OSI but did have mild common carotid artery stenoses at the proximal arteriotomy that caused turbulence. Trimmed patches had more regions of abnormal WSS and OSI at the bifurcation, but 8-mm patches had the largest areas of deleteriously low WSS and high OSI. Qualitative comparison among the four groups confirmed that incorporation of a patch increased areas of low WSS and high OSI at the bifurcation and that this was related to patch width. Closure technique after CEA influences the hemodynamic profile. Patching does not appear to generate favorable flow dynamics. However, a trimmed 5-mm patch may offer hemodynamic benefits over an 8

  12. From hemodynamic towards cardiomechanic sensors in implantable devices

    Science.gov (United States)

    Ferek-Petric, Bozidar

    2013-06-01

    Sensor could significantly improve the cardiac electrotherapy. It has to provide long-term stabile signal not impeding the device longevity and lead reliability. It may not introduce special implantation and adjustment procedures. Hemodynamic sensors based on the blood flow velocity and cardiomechanic sensors based on the lead bending measurement are disclosed. These sensors have a broad clinical utility. Triboelectric and high-frequency lead bending sensors yield accurate and stable signals whereby functioning with every cardiac lead. Moreover, high frequency measurement avoids use of any kind of special hardware mounted on the cardiac lead.

  13. Isolated Grade 5 Renal Trauma in a Hemodynamically Stable Patient

    Directory of Open Access Journals (Sweden)

    Nandu Dantanarayana

    2016-01-01

    Full Text Available Isolated grade 5 renal trauma in a hemodynamically stable patient is rare. It is therefore unsurprising there are conflicting recommendations on management of these injuries from authorities including the AUA, EAU and SIU. We present a 26-year-old male with flank pain following a 3-m fall whilst bicycle riding off a ramp, who was found to have an isolated grade 5 renal injury (shattered kidney. He was managed with early angio-embolization and subsequent nephrectomy due to ongoing bleeding. Further reports of clinician experience with this type of renal injury are needed to clarify best practice in management.

  14. Mathematical modeling of renal hemodynamics in physiology and pathophysiology.

    Science.gov (United States)

    Sgouralis, Ioannis; Layton, Anita T

    2015-06-01

    In addition to the excretion of metabolic waste and toxin, the kidney plays an indispensable role in regulating the balance of water, electrolyte, acid-base, and blood pressure. For the kidney to maintain proper functions, hemodynamic control is crucial. In this review, we describe representative mathematical models that have been developed to better understand the kidney's autoregulatory processes. We consider mathematical models that simulate glomerular filtration, and renal blood flow regulation by means of the myogenic response and tubuloglomerular feedback. We discuss the extent to which these modeling efforts have expanded the understanding of renal functions in health and disease. Copyright © 2015 Elsevier Inc. All rights reserved.

  15. BRAD: Software for BRain Activity Detection from hemodynamic response

    Czech Academy of Sciences Publication Activity Database

    Pidnebesna, Anna; Tomeček, David; Hlinka, Jaroslav

    2018-01-01

    Roč. 156, March (2018), s. 113-119 ISSN 0169-2607 R&D Projects: GA ČR GA13-23940S; GA ČR GA17-01251S; GA ČR GA13-23940S Grant - others:GA MŠk(CZ) LO1611 Institutional support: RVO:67985807 Keywords : deconvolution methods * functional magnetic resonance imaging * hemodynamic response * neuronal activity estimation * Wiener filtering Subject RIV: JC - Computer Hardware ; Software Impact factor: 2.503, year: 2016

  16. Vascular aging and hemodynamic stability in the intraoperative period

    Directory of Open Access Journals (Sweden)

    Ferrante S. Gragasin

    2012-04-01

    Full Text Available The proportion of elderly people in the population is steadily increasing, and the inevitable consequence is that this subpopulation is more frequently represented in common medical procedures and surgeries. Understanding the circulatory changes that accompany the aging process is therefore becoming increasingly timely and relevant. In this short review, we discuss aspects of vascular control in aging that are particularly relevant in the maintenance of intraoperative hemodynamic stability. We subsequently review the effects of certain notable anesthetic agents with respect to the aging vasculature.

  17. Noninvasive hemodynamic assessment, treatment outcome prediction and follow-up of aortic coarctation from MR imaging.

    Science.gov (United States)

    Ralovich, Kristóf; Itu, Lucian; Vitanovski, Dime; Sharma, Puneet; Ionasec, Razvan; Mihalef, Viorel; Krawtschuk, Waldemar; Zheng, Yefeng; Everett, Allen; Pongiglione, Giacomo; Leonardi, Benedetta; Ringel, Richard; Navab, Nassir; Heimann, Tobias; Comaniciu, Dorin

    2015-05-01

    Coarctation of the aorta (CoA) is a congenital heart disease characterized by an abnormal narrowing of the proximal descending aorta. Severity of this pathology is quantified by the blood pressure drop (△P) across the stenotic coarctation lesion. In order to evaluate the physiological significance of the preoperative coarctation and to assess the postoperative results, the hemodynamic analysis is routinely performed by measuring the △P across the coarctation site via invasive cardiac catheterization. The focus of this work is to present an alternative, noninvasive measurement of blood pressure drop △P through the introduction of a fast, image-based workflow for personalized computational modeling of the CoA hemodynamics. The authors propose an end-to-end system comprised of shape and computational models, their personalization setup using MR imaging, and a fast, noninvasive method based on computational fluid dynamics (CFD) to estimate the pre- and postoperative hemodynamics for coarctation patients. A virtual treatment method is investigated to assess the predictive power of our approach. Automatic thoracic aorta segmentation was applied on a population of 212 3D MR volumes, with mean symmetric point-to-mesh error of 3.00 ± 1.58 mm and average computation time of 8 s. Through quantitative evaluation of 6 CoA patients, good agreement between computed blood pressure drop and catheter measurements is shown: average differences are 2.38 ± 0.82 mm Hg (pre-), 1.10 ± 0.63 mm Hg (postoperative), and 4.99 ± 3.00 mm Hg (virtual stenting), respectively. The complete workflow is realized in a fast, mostly-automated system that is integrable in the clinical setting. To the best of our knowledge, this is the first time that three different settings (preoperative--severity assessment, poststenting--follow-up, and virtual stenting--treatment outcome prediction) of CoA are investigated on multiple subjects. We believe that in future-given wider clinical validation

  18. Lumbar internal disc derangement in patients with chronic low back pain: diagnostic value of the MR imaging findings as compared with provoked discography as the standard

    International Nuclear Information System (INIS)

    Park, Hyeon Seon; Park, Jee Young; Lee, Sang Ho; Ahn, Yong; Lee, Sang Yeun

    2006-01-01

    The aim of this study was to evaluate the diagnostic value of the MR imaging findings with provoked discography used as the standard for painful lumbar disc derangement. Two hundred patients (412 discs), (age rang: 21-77 year), with chronic low back pain underwent MRI and provoked discography. We evaluated the MRI T2-WI findings such as disc degeneration, high-Intensity zones and endplate abnormalities. Subsequently, provocative discography was independently performed with using MR imaging, and a painful disc was defined when moderate to severe and concordant pain was provoked. We calculated the sensitivity, specificity, positive predictive value (PPV), and negative predictive value (NPV) of the MRI findings with using provoked discography as the standard. 400 discs showed abnormal findings such as disc degeneration, HIZ and endplate abnormalities on the T2-WI images. 12 discs showed normal finding. HIZ or endplate abnormalities were always combined with disc degeneration. The prevalence of each findings were disc degeneration (400 discs: 97.1%), HIZ (111 discs: 26.9%), type I endplate abnormalities (34 discs: 8.3%), type II endplate abnormalities (75 discs: 18.2%), the combined findings of HIZ and type I endplate abnormalities (2 discs: 0.5%) and the combined findings of HIZ and type II endplate abnormalities (7 discs: 1.7%). The disc degeneration showed high sensitivity (99.5%) and low specificity (5.0%), so only the NPV (91.7%) was significant, and not the PPV (47.8%). Each findings of HIZ (sensitivity, 36.5%, specificity, 81.4%; PPV, 63.18%; NPV, 59.5%), type I endplate abnormalities (11.0%, 94.1%, 61.8% and 54.8%, respectively), type II endplate abnormalities (19.8%, 83.2%, 50.7% and 54.3%, respectively), the combined findings of HIZ and type I endplate abnormalities (0.5%, 99.6%, 50.0% and 53.4%, respectively) and the combined findings of HIZ and type II endplate abnormalities (26.0%, 99.1%, 71.4% and 53.8%, respectively) show high specificity, but low

  19. Hemodynamic Measurement Using Four-Dimensional Phase-Contrast MRI: Quantification of Hemodynamic Parameters and Clinical Applications

    Energy Technology Data Exchange (ETDEWEB)

    Ha, Hojin [POSTECH Biotech Center, Pohang University of Science and Technology, Pohang 37673 (Korea, Republic of); Kim, Guk Bae [Asan Institute of Life Science, Asan Medical Center, University of Ulsan College of Medicine, Seoul 05505 (Korea, Republic of); Kweon, Jihoon [Department of Cardiology, Asan Medical Center, University of Ulsan College of Medicine, Seoul 05505 (Korea, Republic of); Lee, Sang Joon [POSTECH Biotech Center, Pohang University of Science and Technology, Pohang 37673 (Korea, Republic of); Department of Mechanical Engineering, Pohang University of Science and Technology, Pohang 37673 (Korea, Republic of); Kim, Young-Hak [Department of Cardiology, Asan Medical Center, University of Ulsan College of Medicine, Seoul 05505 (Korea, Republic of); Lee, Deok Hee; Yang, Dong Hyun [Department of Radiology, Asan Medical Center, University of Ulsan College of Medicine, Seoul 05505 (Korea, Republic of); Kim, Namkug [Department of Radiology, Asan Medical Center, University of Ulsan College of Medicine, Seoul 05505 (Korea, Republic of); Department of Convergence Medicine, Asan Medical Center, University of Ulsan College of Medicine, Seoul 05505 (Korea, Republic of)

    2016-11-01

    Recent improvements have been made to the use of time-resolved, three-dimensional phase-contrast (PC) magnetic resonance imaging (MRI), which is also named four-dimensional (4D) PC-MRI or 4D flow MRI, in the investigation of spatial and temporal variations in hemodynamic features in cardiovascular blood flow. The present article reviews the principle and analytical procedures of 4D PC-MRI. Various fluid dynamic biomarkers for possible clinical usage are also described, including wall shear stress, turbulent kinetic energy, and relative pressure. Lastly, this article provides an overview of the clinical applications of 4D PC-MRI in various cardiovascular regions.

  20. Hemodynamic measurement using four-dimensional phase-contrast MRI: Quantification of hemodynamic parameters and clinical applications

    Energy Technology Data Exchange (ETDEWEB)

    Ha, Ho Jin; Lee, Sang Joon [POSTECH Biotech Center, Pohang University of Science and Technology, Pohang (Korea, Republic of); Kim, Guk Bae; Kweon, Ji Hoon; Kim, Young Hak; Lee, Deok Hee; Yang, Dong Hyun; KIm, Nam Kug [Asan Medical Center, University of Ulsan College of Medicine, Seoul (Korea, Republic of)

    2016-07-15

    Recent improvements have been made to the use of time-resolved, three-dimensional phase-contrast (PC) magnetic resonance imaging (MRI), which is also named four-dimensional (4D) PC-MRI or 4D flow MRI, in the investigation of spatial and temporal variations in hemodynamic features in cardiovascular blood flow. The present article reviews the principle and analytical procedures of 4D PC-MRI. Various fluid dynamic biomarkers for possible clinical usage are also described, including wall shear stress, turbulent kinetic energy, and relative pressure. Lastly, this article provides an overview of the clinical applications of 4D PC-MRI in various cardiovascular regions.

  1. EVALUATION OF DEXMEDETOMIDINE ON HEMODYNAMICS IN PATIENTS UNDERGOING LAPAROSCOPIC CHOLECYSTECTOMY

    Directory of Open Access Journals (Sweden)

    Penchalaiah

    2015-09-01

    Full Text Available BACKGROUND: Dexmedetomidine a newer generation highly selective alpha - 2 adrenergic agonist are well known to inhibit catecholamine release. The present study compares the effects of intravenously administered dexmedetomidine to attenuate hemodynamic response to pneumoperitoneum to laparoscopic cholecystectomy under general anaesthesia. METHODOLOGY: 60 patients ASA Physical status I and II, aged between 18 and 50 years of either sex, scheduled for elective laparoscopic cholecy stectomy were randomized in to 2 groups ( group D and S inn a double blind fashion to receive either Dexmedetomidine ( 1microgram/kg in 100ml of 0.9% normal saline or only 0.9%plain normal saline respectively. It is given 30 min prior to induction. Patient vitals like HR, SBP, DBP, MAP were monitored during the study at various time intervals. RESULTS: Following intubation and pneumoperitoneum there significant rise in HR, MAP, SBP, DBP in group S but no significant rise in Group D. CONCLUSION: Dexmedetomid ine given in a dose of 1microgram/kg as a premedication is e ffective in attenuating the hemodynamic responses in laparoscopic surgery

  2. Optimal hemodynamic response model for functional near-infrared spectroscopy

    Directory of Open Access Journals (Sweden)

    Muhammad Ahmad Kamran

    2015-06-01

    Full Text Available Functional near-infrared spectroscopy (fNIRS is an emerging non-invasive brain imaging technique and measures brain activities by means of near-infrared light of 650-950 nm wavelengths. The cortical hemodynamic response (HR differs in attributes at different brain regions and on repetition of trials, even if the experimental paradigm is kept exactly the same. Therefore, an HR model that can estimate such variations in the response is the objective of this research. The canonical hemodynamic response function (cHRF is modeled by using two Gamma functions with six unknown parameters. The HRF model is supposed to be linear combination of HRF, baseline and physiological noises (amplitudes and frequencies of physiological noises are supposed to be unknown. An objective function is developed as a square of the residuals with constraints on twelve free parameters. The formulated problem is solved by using an iterative optimization algorithm to estimate the unknown parameters in the model. Inter-subject variations in HRF and physiological noises have been estimated for better cortical functional maps. The accuracy of the algorithm has been verified using ten real and fifteen simulated data sets. Ten healthy subjects participated in the experiment and their HRF for finger-tapping tasks have been estimated and analyzed. The statistical significance of the estimated activity strength parameters has been verified by employing statistical analysis, i.e., (t-value >tcritical and p-value < 0.05.

  3. Weight loss improves renal hemodynamics in patients with metabolic syndrome.

    Science.gov (United States)

    Ezequiel, Danielle Guedes Andrade; Costa, Monica Barros; Chaoubah, Alfredo; de Paula, Rogerio Baumgratz

    2012-03-01

    We investigated the impact of weight loss on urinary albumin excretion (UAE) and creatinine clearance in obese patients with metabolic syndrome. Thirty-five obese patients undertook a 12-week calorie-restricted diet. The patients underwent a metabolic (oral glucose tolerance test, plasma lipids, and uric acid) and renal hemodynamic evaluations (creatinine clearance and urinary albumin excretion) before (phase 1), and after the 12-week diet (phase 2). After the dietary intervention, the subjects were divided into two groups: patients who achieved the target weight reduction (R: responders, n = 14), and patients who did not (NR: non-responders, n = 21). The patients in Group R showed an improvement in lipid profile, a decrease in UAE (median = 162.5 mg/24 hours, range: 0.8 to 292 mg/24 hours, at phase 1 versus 10.4 mg/24 hours, range: 1.6 to 22.4 mg/24 hours, at phase 2), and a significant reduction in creatinine clearance (121.4 ± 66.5 mL/min. in phase 1 to 92.9 ± 35.6 mL/min. at the end of phase 2, p = 0.001). In Group NR, no statistically significant differences were observed between phases 1 and 2. Body weight reduction has a positive impact on renal hemodynamics, decreasing urinary albumin excretion as well as glomerular hyperfiltration in obese patients with metabolic syndrome.

  4. Weight loss improves renal hemodynamics in patients with metabolic syndrome

    Directory of Open Access Journals (Sweden)

    Danielle Guedes Andrade Ezequiel

    2012-03-01

    Full Text Available OBJECTIVE: We investigated the impact of weight loss on urinary albumin excretion (UAE and creatinine clearance in obese patients with metabolic syndrome. METHODS: Thirty-five obese patients undertook a 12-week calorie-restricted diet. The patients underwent a metabolic (oral glucose tolerance test, plasma lipids, and uric acid and renal hemodynamic evaluations (creatinine clearance and urinary albumin excretion before (phase 1, and after the 12-week diet (phase 2. RESULTS: After the dietary intervention, the subjects were divided into two groups: patients who achieved the target weight reduction (R: responders, n = 14, and patients who did not (NR: non-responders, n = 21. The patients in Group R showed an improvement in lipid profile, a decrease in UAE (median = 162.5 mg/24 hours, range: 0.8 to 292 mg/24 hours, at phase 1 versus 10.4 mg/24 hours, range: 1.6 to 22.4 mg/24 hours, at phase 2, and a significant reduction in creatinine clearance (121.4 ± 66.5 mL/min. in phase 1 to 92.9 ± 35.6 mL/min. at the end of phase 2, p = 0.001. In Group NR, no statistically significant differences were observed between phases 1 and 2. CONCLUSION: Body weight reduction has a positive impact on renal hemodynamics, decreasing urinary albumin excretion as well as glomerular hyperfiltration in obese patients with metabolic syndrome.

  5. Prefrontal Hemodynamic Changes Associated with Subjective Sense of Occlusal Discomfort

    Directory of Open Access Journals (Sweden)

    Yumie Ono

    2015-01-01

    Full Text Available We used functional near-infrared spectroscopy to measure prefrontal brain activity accompanying the physical sensation of oral discomfort that arose when healthy young-adult volunteers performed a grinding motion with mild occlusal elevation (96 μm. We simultaneously evaluated various forms of occlusal discomfort using the visual analogue scale (VAS and hemodynamic responses to identify the specific prefrontal activity that occurs with increased occlusal discomfort. The Oxy-Hb responses of selected channels in the bilateral frontopolar and dorsolateral prefrontal cortices increased in participants who reported increased severity of occlusal discomfort, while they decreased in those who reported no change or decreased occlusal discomfort during grinding. Moreover, the cumulative values of Oxy-Hb response in some of these channels were statistically significant predictive factors for the VAS scores. A generalized linear model analysis of Oxy-Hb signals in a group of participants who reported increased discomfort further indicated significant cerebral activation in the right frontopolar and dorsolateral prefrontal cortices that overlapped with the results of correlation analyses. Our results suggest that the increased hemodynamic responses in the prefrontal area reflect the top-down control of attention and/or self-regulation against the uncomfortable somatosensory input, which could be a possible marker to detect the subjective sense of occlusal discomfort.

  6. The Effect of Hemodynamics on Cerebral Aneurysm Morphology

    Science.gov (United States)

    Metcalfe, Ralph; Mantha, Aishwarya; Karmonik, Christof; Strother, Charles

    2004-11-01

    One of the difficulties in applying principles of hemodynamics to the study of blood flow in aneurysms are the drastic variations in possible shape of both the aneurysms and the parent arteries in the region of interest. We have taken data from three para-opthalmic internal carotid artery aneurysms using 3D-digital subtraction angiography (3D-DSA) and performed CFD simulations of steady and unsteady flows through the three different cases using the same pressure gradients and pulsatile flow waveforms (based on the Ku model for flow through the Carotid bifurcation). We have found that the total pressure differential within the aneurysms is consistent with the direction of flow, and that the dynamic pressure gradient within the aneurysm is very small compared with the static pressure variations. Wall shear stresses were highest near regions of sharp arterial curvature, but always remained low inside the aneurysm. These results suggest a more complex role for hemodynamics in aneurysm generation, growth and rupture.

  7. Complex Coronary Hemodynamics - Simple Analog Modelling as an Educational Tool.

    Science.gov (United States)

    Parikh, Gaurav R; Peter, Elvis; Kakouros, Nikolaos

    2017-01-01

    Invasive coronary angiography remains the cornerstone for evaluation of coronary stenoses despite there being a poor correlation between luminal loss assessment by coronary luminography and myocardial ischemia. This is especially true for coronary lesions deemed moderate by visual assessment. Coronary pressure-derived fractional flow reserve (FFR) has emerged as the gold standard for the evaluation of hemodynamic significance of coronary artery stenosis, which is cost effective and leads to improved patient outcomes. There are, however, several limitations to the use of FFR including the evaluation of serial stenoses. In this article, we discuss the electronic-hydraulic analogy and the utility of simple electrical modelling to mimic the coronary circulation and coronary stenoses. We exemplify the effect of tandem coronary lesions on the FFR by modelling of a patient with sequential disease segments and complex anatomy. We believe that such computational modelling can serve as a powerful educational tool to help clinicians better understand the complexity of coronary hemodynamics and improve patient care.

  8. Bicuspid aortic valve hemodynamics: a fluid-structure interaction study

    Science.gov (United States)

    Chandra, Santanu; Seaman, Clara; Sucosky, Philippe

    2011-11-01

    The bicuspid aortic valve (BAV) is a congenital defect in which the aortic valve forms with two leaflets instead of three. While calcific aortic valve disease (CAVD) also develops in the normal tricuspid aortic valve (TAV), its progression in the BAV is more rapid. Although studies have suggested a mechano-potential root for the disease, the native BAV hemodynamics remains largely unknown. This study aimed at characterizing BAV hemodynamics and quantifying the degree of wall-shear stress (WSS) abnormality on BAV leaflets. Fluid-structure interaction models validated with particle-image velocimetry were designed to predict the flow and leaflet dynamics in idealized TAV and BAV anatomies. Valvular function was quantified in terms of the effective orifice area. The regional leaflet WSS was characterized in terms of oscillatory shear index, temporal shear magnitude and temporal shear gradient. The predictions indicate the intrinsic degree of stenosis of the BAV anatomy, reveal drastic differences in shear stress magnitude and pulsatility on BAV and TAV leaflets and confirm the side- and site-specificity of the leaflet WSS. Given the ability of abnormal fluid shear stress to trigger valvular inflammation, these results support the existence of a mechano-etiology of CAVD in the BAV.

  9. Life Satisfaction and Hemodynamic Reactivity to Mental Stress.

    Science.gov (United States)

    Schwerdtfeger, Andreas; Gaisbachgrabner, Kerstin; Traunmüller, Claudia

    2017-06-01

    Satisfaction with life has been considered a health-protective variable, which could impact cardiovascular morbidity and mortality. However, few studies have examined the physiological pathways involved in the potentially salutary effect of life satisfaction. It was hypothesized that life satisfaction should be associated with a cardiovascular response profile that signals challenge (i.e., higher cardiac output, lower peripheral resistance), rather than threat during a mental stress task. A sample of 75 healthy, medication-free men without clinical signs of psychological disorders who worked full-time and occupied highly demanding positions participated in this study. They performed two mental stress tasks (n-back) with varying degrees of difficulty. The tasks were embedded between a baseline and a recovery period. Cardiovascular and hemodynamic variables (heart rate, blood pressure, cardiac output, total peripheral resistance) were recorded by means of impedance cardiography. Individuals who were more satisfied with their life displayed higher cardiac output and lower peripheral resistance levels during the stress tasks, indicating a challenge rather than a threat profile. Findings were robust when controlled for physical activity, smoking, age, and depressive symptoms. Life satisfaction could be positively correlated with beneficial hemodynamic stress reactivity, indicating that individuals with higher levels of life satisfaction can more adaptively cope with stress. Increased cardiac output and decreased peripheral resistance during stress may constitute one route through which life satisfaction can benefit health.

  10. The analysis of solutions behaviour of Van der Pol Duffing equation describing local brain hemodynamics

    Science.gov (United States)

    Cherevko, A. A.; Bord, E. E.; Khe, A. K.; Panarin, V. A.; Orlov, K. J.

    2017-10-01

    This article proposes the generalized model of Van der Pol — Duffing equation for describing the relaxation oscillations in local brain hemodynamics. This equation connects the velocity and pressure of blood flow in cerebral vessels. The equation is individual for each patient, since the coefficients are unique. Each set of coefficients is built based on clinical data obtained during neurosurgical operation in Siberian Federal Biomedical Research Center named after Academician E. N. Meshalkin. The equation has solutions of different structure defined by the coefficients and right side. We investigate the equations for different patients considering peculiarities of their vessel systems. The properties of approximate analytical solutions are studied. Amplitude-frequency and phase-frequency characteristics are built for the small-dimensional solution approximations.

  11. Multiparametric optical coherence tomography imaging of the inner retinal hemodynamic response to visual stimulation

    Science.gov (United States)

    Radhakrishnan, Harsha; Srinivasan, Vivek J.

    2013-08-01

    The hemodynamic response to neuronal activation is a well-studied phenomenon in the brain, due to the prevalence of functional magnetic resonance imaging. The retina represents an optically accessible platform for studying lamina-specific neurovascular coupling in the central nervous system; however, due to methodological limitations, this has been challenging to date. We demonstrate techniques for the imaging of visual stimulus-evoked hyperemia in the rat inner retina using Doppler optical coherence tomography (OCT) and OCT angiography. Volumetric imaging with three-dimensional motion correction, en face flow calculation, and normalization of dynamic signal to static signal are techniques that reduce spurious changes caused by motion. We anticipate that OCT imaging of retinal functional hyperemia may yield viable biomarkers in diseases, such as diabetic retinopathy, where the neurovascular unit may be impaired.

  12. Effect of confounding variables on hemodynamic response function estimation using averaging and deconvolution analysis: An event-related NIRS study.

    Science.gov (United States)

    Aarabi, Ardalan; Osharina, Victoria; Wallois, Fabrice

    2017-07-15

    Slow and rapid event-related designs are used in fMRI and functional near-infrared spectroscopy (fNIRS) experiments to temporally characterize the brain hemodynamic response to discrete events. Conventional averaging (CA) and the deconvolution method (DM) are the two techniques commonly used to estimate the Hemodynamic Response Function (HRF) profile in event-related designs. In this study, we conducted a series of simulations using synthetic and real NIRS data to examine the effect of the main confounding factors, including event sequence timing parameters, different types of noise, signal-to-noise ratio (SNR), temporal autocorrelation and temporal filtering on the performance of these techniques in slow and rapid event-related designs. We also compared systematic errors in the estimates of the fitted HRF amplitude, latency and duration for both techniques. We further compared the performance of deconvolution methods based on Finite Impulse Response (FIR) basis functions and gamma basis sets. Our results demonstrate that DM was much less sensitive to confounding factors than CA. Event timing was the main parameter largely affecting the accuracy of CA. In slow event-related designs, deconvolution methods provided similar results to those obtained by CA. In rapid event-related designs, our results showed that DM outperformed CA for all SNR, especially above -5 dB regardless of the event sequence timing and the dynamics of background NIRS activity. Our results also show that periodic low-frequency systemic hemodynamic fluctuations as well as phase-locked noise can markedly obscure hemodynamic evoked responses. Temporal autocorrelation also affected the performance of both techniques by inducing distortions in the time profile of the estimated hemodynamic response with inflated t-statistics, especially at low SNRs. We also found that high-pass temporal filtering could substantially affect the performance of both techniques by removing the low-frequency components of

  13. Prognostic value of renal hemodynamic characteristics in patients with proliferative lupus nephritis

    NARCIS (Netherlands)

    Martens, Henk A.; Bijl, Marc; Kallenberg, Cees G. M.

    2007-01-01

    Background/Aim: Previous studies showed that renal hemodynamic parameters, especially the filtration fraction ( FF), are decreased in patients with active lupus nephritis ( LN). In this study, we evaluate the prognostic value of renal hemodynamic function tests on the renal outcome in patients with

  14. Hemodynamic volumetry using transpulmonary ultrasound dilution (TPUD) technology in a neonatal animal model

    NARCIS (Netherlands)

    Vrancken, S.L.A.G.; Heijst, A.F.J. van; Hopman, J.C.W.; Liem, K.D.; Hoeven, J.G. van der; Boode, W.P. de

    2015-01-01

    To analyze changes in cardiac output and hemodynamic volumes using transpulmonary ultrasound dilution (TPUD) in a neonatal animal model under different hemodynamic conditions. 7 lambs (3.5-8.3 kg) under general anesthesia received arterial and central venous catheters. A Gore-Tex((R)) shunt was

  15. Use of lignocaine or nitroglycerine for blunting of hemodynamic stress response during electroconvulsive therapy

    Directory of Open Access Journals (Sweden)

    Muhammad Umar Zahoor

    2014-01-01

    Conclusion: NTG provided more hemodynamic stability in post-ECT period as compared to lignocaine which only prevented a surge in HR without any effect on MAP. We conclude that NTG can safely be instituted for anaesthesia in ECT patients for prevention of hemodynamic stress response.

  16. Year in review in journal of clinical monitoring and computing 2014 : cardiovascular and hemodynamic monitoring

    NARCIS (Netherlands)

    Bendjelid, Karim; Rex, Steffen; Scheeren, Thomas; Critchley, Lester

    Hemodynamic instability is a common sign in critically ill patients and its importance has been increasingly recognized during the last 20 years. Indeed, It is now appreciated that an adequate hemodynamic monitoring associated to reactive vigorous therapy is able to decrease the present ominous

  17. Journal of Clinical Monitoring and Computing 2015 end of year summary : cardiovascular and hemodynamic monitoring

    NARCIS (Netherlands)

    Bendjelid, Karim; Rex, Steffen; Scheeren, Thomas; Saugel, Bernd

    Hemodynamic monitoring is essential in critically ill patients. In this regard, the Journal of Clinical Monitoring and Computing (JCMC) has become an ideal platform for publishing cardiovascular and hemodynamic monitoring-related research, as reflected by an increasing number of articles related to

  18. Effect of tilting on cerebral hemodynamics in preterm and term infants

    NARCIS (Netherlands)

    Pichler, G; van Boetzelar, MC; Muller, W; Urlesberger, B

    2001-01-01

    Tilting is known to cause changes in hemodynamics due to hydrostatic pressure. The present study is an analysis of changes in cerebral hemodynamics measured by near infrared spectroscopy (NIRS) following tilting up and down in preterm and term infants. A significantly different effect of tilting up

  19. Exercise hemodynamics in patients with and without diastolic dysfunction and preserved ejection fraction after myocardial infarction

    DEFF Research Database (Denmark)

    Andersen, Mads J; Ersbøll, Mads; Bro-Jeppesen, John

    2012-01-01

    Left ventricular diastolic dysfunction (DD) is common after myocardial infarction (MI) despite preservation of left ventricular ejection fraction, yet it remains unclear how or whether DD affects cardiac hemodynamics with stress.......Left ventricular diastolic dysfunction (DD) is common after myocardial infarction (MI) despite preservation of left ventricular ejection fraction, yet it remains unclear how or whether DD affects cardiac hemodynamics with stress....

  20. Differential hemodynamic effects of exercise and volume expansion in people with and without heart failure

    DEFF Research Database (Denmark)

    Andersen, Mads Jønsson; Olson, Thomas P; Melenovsky, Vojtech

    2015-01-01

    BACKGROUND:Invasive hemodynamic exercise testing is commonly used in the evaluation of patients with suspected heart failure with preserved ejection fraction (HFpEF) or pulmonary hypertension. Saline loading has been suggested as an alternative provocative maneuver, but the hemodynamic changes...

  1. Hemodynamic analysis of a novel bioresorbable scaffold in porcine coronary artery model

    NARCIS (Netherlands)

    Tenekecioglu, Erhan; Torii, Ryo; Bourantas, Christos V.; Cavalcante, Rafael; Sotomi, Yohei; Zeng, Yaping; Collet, Carlos; Crake, Tom; Abizaid, Alexandre; Onuma, Yoshinobu; Su, Solomon; Santoso, Teguh; Serruys, Patrick W.

    2017-01-01

    The shear stress distribution assessment can provide useful insights for the hemodynamic performance of the implanted stent/scaffold. Our aim was to investigate the effect of a novel bioresorbable scaffold, Mirage on local hemodynamics in animal models. The main epicardial coronary arteries of 7

  2. Novel Use of a Noninvasive Hemodynamic Monitor in a Personalized, Active Learning Simulation

    Science.gov (United States)

    Zoller, Jonathan K.; He, Jianghua; Ballew, Angela T.; Orr, Walter N.; Flynn, Brigid C.

    2017-01-01

    The present study furthered the concept of simulation-based medical education by applying a personalized active learning component. We tested this novel approach utilizing a noninvasive hemodynamic monitor with the capability to measure and display in real time numerous hemodynamic parameters in the exercising participant. Changes in medical…

  3. Usefulness of time-resolved projection MRA on evaluation of hemodynamics in cerebral occlusive diseases

    International Nuclear Information System (INIS)

    Oka, Yoshihisa; Kusunoki, Katsusuke; Nochide, Ichiro; Igase, Keiji; Harada, Hironobu; Sadamoto, Kazuhiko; Nagasawa, Kiyoshi

    2001-01-01

    The usefulness for evaluation of cerebral hemodynamics using time-resolved projection MRA was studied in normal volunteers and patients of cerebrovascular diseases. Six normal volunteers and ten patients with cerebrovascular occlusive diseases including 6 of IC occlusion and 4 of post EC/IC bypass surgery underwent time-resolved projection MRA on a 1.5 T clinical MRI system. Projection angiograms are acquired with 2D-fast SPGR sequence with a time resolution of approximately one image per second, 40 images being acquired consecutively before and after bolus injection Gd-DTPA. And all images were calculated by complex subtraction from the background mask in a work station. In normal volunteers, the quality of images of time-resolved projection MRA was satisfactory. The arteries from internal carotid artery through M2 segment of middle cerebral artery and all major venous systems were well portrayed. In 4 cases of IC occlusion who were assessed the collateral flow through the anterior communicating artery and posterior communicating artery, there were delayed to demonstrate the ipsilateral MCA. However, in 2 cases of IC occlusion that were assessed the collateral flow through leptomeningeal anastomosis, ipsilateral MCA and collateral circulation were not demonstrated. In all patients of post EC/IC bypass surgery, the patency of EC/IC bypass could be evaluated as properly with time-resolved projection MRA as 3D-TOF MRA. Although the temporal and spatial resolutions are insufficient, time-resolved projection MRA was power-full non-invasive method to evaluate the cerebral hemodynamics vis the basal communicating arteries in IC occlusion and identify the patency of EC/IC bypass. (author)

  4. The Adverse Events and Hemodynamic Effects of Adenosine-Based Cardiac MRI

    Energy Technology Data Exchange (ETDEWEB)

    Voigtlander, Thomas; Magedanz, Annett; Schmermund, Axel [Cardiovascular Center Bethanien (CCB), Frankfurt (Germany); Bramlage, Peter [Technical University of Dresden, Dresden (Germany); Elsaesser, Amelie [University of Mainz, Mainz (Germany); Kauczor, Hans-Ulrich; Mohrs, Oliver K. [University of Heidelberg, Heidelberg (Germany)

    2011-08-15

    We wanted to prospectively assess the adverse events and hemodynamic effects associated with an intravenous adenosine infusion in patients with suspected or known coronary artery disease and who were undergoing cardiac MRI. One hundred and sixty-eight patients (64 {+-} 9 years) received adenosine (140 {mu}g/kg/min) during cardiac MRI. Before and during the administration, the heart rate, systemic blood pressure, and oxygen saturation were monitored using a MRI-compatible system. We documented any signs and symptoms of potential adverse events. In total, 47 out of 168 patients (28%) experienced adverse effects, which were mostly mild or moderate. In 13 patients (8%), the adenosine infusion was discontinued due to intolerable dyspnea or chest pain. No high grade atrioventricular block, bronchospasm or other life-threatening adverse events occurred. The hemodynamic measurements showed a significant increase in the heart rate during adenosine infusion (69.3 {+-} 11.7 versus 82.4 {+-} 13.0 beats/min, respectively; p < 0.001). A significant but clinically irrelevant increase in oxygen saturation occurred during adenosine infusion (96 {+-} 1.9% versus 97 {+-} 1.3%, respectively; p < 0.001). The blood pressure did not significantly change during adenosine infusion (systolic: 142.8 {+-} 24.0 versus 140.9 {+-} 25.7 mmHg; diastolic: 80.2 {+-} 12.5 mmHg versus 78.9 {+-} 15.6, respectively). This study confirms the safety of adenosine infusion during cardiac MRI. A considerable proportion of all patients will experience minor adverse effects and some patients will not tolerate adenosine infusion. However, all adverse events can be successfully managed by a radiologist. The increased heart rate during adenosine infusion highlights the need to individually adjust the settings according to the patient, e.g., the number of slices of myocardial perfusion imaging.

  5. Transdermal glyceryl trinitrate (nitroglycerin in healthy persons: acute effects on skin temperature and hemodynamic orthostatic response

    Directory of Open Access Journals (Sweden)

    Eva Maria Augusta Boeckh Haebisch

    Full Text Available In order to find an explanation for individual reactions to transdermal glyceryl trinitrate (GTN we studied the skin temperature and hemodynamic reactions in 63 healthy persons. The data were obtained before and after the application of GTN and Glycerin (GL placebo patches, during one hour. The skin temperature was measured on both forearms, the local (left sided and systemic (right sided reaction on GTN was related to the skin fold and the calculated body fat content. The bilateral rise of skin temperature and its duration was higher and longer in obese than in lean persons mainly in obese women. The UV induced thermo and the later photothermoreaction (Erythema was reduced on the left forearm after the application of GTN and GL patches. The observed hemodynamic GTN effect confirmed known postural reactions, such as decreased arterial pressure (ΔmAP = -2.9%, increased heart rate (ΔHR = +7,4% and QTc prolongation (ΔQTc = +4,9% in upright position. An adverse drug effect with increased mean blood pressure (ΔmAP = +12% and increased heart rate (ΔHR = + 10.4% mainly in supine position was observed in 11 % of the participants, but only in men. Such a reaction was already described by Murell, 1879. Individual GTN effects were analyzed and related to habits and family history. In male smokers and in persons with hypertensive and diabetic close relatives, the hypotensive GTN effect was accentuated in supine position. In the upright position the group with hypertensives in the family presented a moderate hypotensive reaction without secondary tachycardia and the smokers presented only a slightly increased heart rate. Our observations suggest that individual reactions to transdermal glyceryl trinitrate (GTN with its active component nitric oxide (NO depends on physiological conditions, related to endogenous vasoactive substances, mainly the interaction with EDRF (the endogenous NO and the activity of the Renin-Angiotensin System.

  6. The Adverse Events and Hemodynamic Effects of Adenosine-Based Cardiac MRI

    International Nuclear Information System (INIS)

    Voigtlander, Thomas; Magedanz, Annett; Schmermund, Axel; Bramlage, Peter; Elsaesser, Amelie; Kauczor, Hans-Ulrich; Mohrs, Oliver K.

    2011-01-01

    We wanted to prospectively assess the adverse events and hemodynamic effects associated with an intravenous adenosine infusion in patients with suspected or known coronary artery disease and who were undergoing cardiac MRI. One hundred and sixty-eight patients (64 ± 9 years) received adenosine (140 μg/kg/min) during cardiac MRI. Before and during the administration, the heart rate, systemic blood pressure, and oxygen saturation were monitored using a MRI-compatible system. We documented any signs and symptoms of potential adverse events. In total, 47 out of 168 patients (28%) experienced adverse effects, which were mostly mild or moderate. In 13 patients (8%), the adenosine infusion was discontinued due to intolerable dyspnea or chest pain. No high grade atrioventricular block, bronchospasm or other life-threatening adverse events occurred. The hemodynamic measurements showed a significant increase in the heart rate during adenosine infusion (69.3 ± 11.7 versus 82.4 ± 13.0 beats/min, respectively; p < 0.001). A significant but clinically irrelevant increase in oxygen saturation occurred during adenosine infusion (96 ± 1.9% versus 97 ± 1.3%, respectively; p < 0.001). The blood pressure did not significantly change during adenosine infusion (systolic: 142.8 ± 24.0 versus 140.9 ± 25.7 mmHg; diastolic: 80.2 ± 12.5 mmHg versus 78.9 ± 15.6, respectively). This study confirms the safety of adenosine infusion during cardiac MRI. A considerable proportion of all patients will experience minor adverse effects and some patients will not tolerate adenosine infusion. However, all adverse events can be successfully managed by a radiologist. The increased heart rate during adenosine infusion highlights the need to individually adjust the settings according to the patient, e.g., the number of slices of myocardial perfusion imaging.

  7. Non-parametric temporal modeling of the hemodynamic response function via a liquid state machine.

    Science.gov (United States)

    Avesani, Paolo; Hazan, Hananel; Koilis, Ester; Manevitz, Larry M; Sona, Diego

    2015-10-01

    Standard methods for the analysis of functional MRI data strongly rely on prior implicit and explicit hypotheses made to simplify the analysis. In this work the attention is focused on two such commonly accepted hypotheses: (i) the hemodynamic response function (HRF) to be searched in the BOLD signal can be described by a specific parametric model e.g., double-gamma; (ii) the effect of stimuli on the signal is taken to be linearly additive. While these assumptions have been empirically proven to generate high sensitivity for statistical methods, they also limit the identification of relevant voxels to what is already postulated in the signal, thus not allowing the discovery of unknown correlates in the data due to the presence of unexpected hemodynamics. This paper tries to overcome these limitations by proposing a method wherein the HRF is learned directly from data rather than induced from its basic form assumed in advance. This approach produces a set of voxel-wise models of HRF and, as a result, relevant voxels are filterable according to the accuracy of their prediction in a machine learning framework. This approach is instantiated using a temporal architecture based on the paradigm of Reservoir Computing wherein a Liquid State Machine is combined with a decoding Feed-Forward Neural Network. This splits the modeling into two parts: first a representation of the complex temporal reactivity of the hemodynamic response is determined by a universal global "reservoir" which is essentially temporal; second an interpretation of the encoded representation is determined by a standard feed-forward neural network, which is trained by the data. Thus the reservoir models the temporal state of information during and following temporal stimuli in a feed-back system, while the neural network "translates" this data to fit the specific HRF response as given, e.g. by BOLD signal measurements in fMRI. An empirical analysis on synthetic datasets shows that the learning process can

  8. A novel non invasive measurement of hemodynamic parameters: Comparison of single-chamber ventricular and dual-chamber pacemaker

    Directory of Open Access Journals (Sweden)

    Ingrid M. Pardede

    2008-03-01

    Full Text Available We carried out a cross sectional study to analyze hemodynamic parameters of single-chamber ventricular pacemaker compared with dual-chamber pacemaker by using thoracic electrical bioimpedance monitoring method (Physio Flow™ - a novel simple non-invasive measurement. A total of 48 consecutive outpatients comprised of 27 single chamber pacemaker and 21 dual chamber were analyzed. We measured cardiac parameters: heart rate, stroke volume index, cardiac output index, estimated ejection fraction, end diastolic volume, early diastolic function ratio, thoracic fluid index, and systemic parameters: left cardiac work index and systemic vascular resistance index. Baseline characteristic and pacemaker indication were similar in both groups. Cardiac parameters assessment revealed no significant difference between single-chamber pacemaker and dual-chamber pacemaker in heart rate, stroke volume index, cardiac index, estimated ejection fraction, end-diastolic volume, thoracic fluid index. There was significantly higher early diastolic function ratio in single-chamber pacemaker compared to dual-chamber pacemaker: 92% (10.2-187.7% vs. 100.6% (48.7-403.2%; p=0.006. Systemic parameters assessment revealed significantly higher left cardiac work index in single-chamber group than dual-chamber group 4.9 kg.m/m² (2.8-7.6 kg.m/m² vs. 4.3 kg.m/m² (2.9-7.2 kg.m/m²; p=0.004. There was no significant difference on systemic vascular resistance in single-chamber compared to dual-chamber pacemaker. Single-chamber ventricular pacemaker provides similar stroke volume, cardiac output and left cardiac work, compared to dual-chamber pacemaker. A non-invasive hemodynamic measurement using thoracic electrical bioimpedance is feasible for permanent pacemaker outpatients. (Med J Indones 2008; 17: 25-32Keywords: Permanent pacemaker, single chamber, dual chamber, thoracic electrical bioimpedance, hemodynamic parameter

  9. A comparative study of fluoride ingestion levels, serum thyroid hormone & TSH level derangements, dental fluorosis status among school children from endemic and non-endemic fluorosis areas.

    Science.gov (United States)

    Singh, Navneet; Verma, Kanika Gupta; Verma, Pradhuman; Sidhu, Gagandeep Kaur; Sachdeva, Suresh

    2014-01-03

    The study was undertaken to determine serum/urinary fluoride status and comparison of free T4, free T3 and thyroid stimulating hormone levels of 8 to 15 years old children with and without dental fluorosis living in an endemic and non-endemic fluorosis area. A sample group of 60 male and female school children, with or without dental fluorosis, consuming fluoride-contaminated water in endemic fluoride area of Udaipur district, Rajasthan were selected through a school dental fluorosis survey. The sample of 10 children of same age and socio-economic status residing in non endemic areas who did not have dental fluorosis form controls. Fluoride determination in drinking water, urine and blood was done with Ion 85 Ion Analyzer Radiometer with Hall et al. method. The thyroid gland functional test was done by Immonu Chemiluminiscence Micropartical Assay with Bayer Centaur Autoanalyzer. The significantly altered FT3, FT4 and TSH hormones level in both group1A and 1B school children were noted. The serum and urine fluoride levels were found to be increased in both the groups. A significant relationship of water fluoride to urine and serum fluoride concentration was seen. The serum fluoride concentration also had significant relationship with thyroid hormone (FT3/FT4) and TSH concentrations. The testing of drinking water and body fluids for fluoride content, along with FT3, FT4, and TSH in children with dental fluorosis is desirable for recognizing underlying thyroid derangements and its impact on fluorosis.

  10. MR image findings on advanced internal derangement of the temporomandibular joints. Cases of disc position changed from anterior disc displacement with reduction to without reduction

    International Nuclear Information System (INIS)

    Igarashi, Chinami; Kobayashi, Kaoru; Yuasa, Masao; Imanaka, Masahiro; Yamamoto, Akira

    2005-01-01

    This study was designed to evaluate the suggestion that the clinical findings and MR image findings of anterior disc displacement with reduction cases could not reduce the disc displacement within the follow-up period. We selected 26 joints without remarkable bone changes in the condylar head or glenoid fossa in which reduction disappeared during follow-up. Clinical evaluation focused on temporomandibular pain, trismus, and joint sound. MR imaging was targeted for configuration of articular disc, degree of disc displacement, and condylar head position. Clinical signs observed with progression of the condition were disappearance of joint sound in 12/26 joints (46.1%), temporomandibular pain in 15/26 joints (57.6%), and decreased distance of opening mouth in 19/26 joints (73%). MR image findings were disc configuration changes in 12/26 joints (46.1%), increased degree of anterior displacement of disc in 20/26 joints (76.9%), and condylar head position changes in 9/26 joints (34.6%). It is suggested that the advanced stage of internal derangement is closely associated with the degree of disc displacement. (author)

  11. Race predictors and hemodynamic alteration after an ultra-trail marathon race

    Directory of Open Access Journals (Sweden)

    Taksaudom N

    2017-10-01

    Full Text Available Noppon Taksaudom,1 Natee Tongsiri,2 Amarit Potikul,1 Chawakorn Leampriboon,1 Apichat Tantraworasin,1 Anong Chaiyasri,1 1Cardiovascular and Thoracic Surgery Unit, Department of Surgery, Chiang Mai University Hospital, 2Department of Mathematics, Faculty of Science, Chiang Mai University, Chiang Mai, Thailand Objective: Unique rough-terrain ultra-trail running races have increased in popularity. Concerns regarding the suitability of the candidates make it difficult for organizers to manage safety regulations. The purpose of this study was to identify possible race predictors and assess hemodynamic change after long endurance races.Methods: We studied 228 runners who competed in a 66 km-trail running race. A questionnaire and noninvasive hemodynamic flow assessment including blood pressure, heart rate, stroke volume, stroke volume variation, systemic vascular resistance, cardiac index, and oxygen saturation were used to determine physiologic alterations and to identify finish predictors. One hundred and thirty volunteers completed the questionnaire, 126 participants had a prerace hemodynamic assessment, and 33 of these participants completed a postrace assessment after crossing the finish line. The participants were divided into a finisher group and a nonfinisher group.Results: The average age of all runners was 37 years (range of 24–56 years. Of the 228 ­runners, 163 (71.5% were male. There were 189 (82.9% finishers. Univariable analysis indicated that the finish predictors included male gender, longest distance ever run, faster running records, and lower diastolic pressure. Only a lower diastolic pressure was a significant predictor of race finishing (diastolic blood pressure 74–84 mmHg: adjusted odd ratio 3.81; 95% confidence interval [CI]  =1.09–13.27 and diastolic blood pressure <74 mmHg: adjusted odd ratio 7.74; 95% CI =1.57–38.21 using the figure from the multivariable analysis. Among the finisher group, hemodynamic parameters

  12. Short-term hemodynamic effect of angiotensin-converting enzyme inhibition in patients with severe aortic stenosis

    DEFF Research Database (Denmark)

    Dalsgaard, Morten; Iversen, Kasper; Kjaergaard, Jesper

    2014-01-01

    BACKGROUND: In patients with severe aortic stenosis (AS), treatment with angiotensin-converting enzyme inhibitors has previously been considered contraindicated. However, there is a lack of clinical evidence to confirm these potential hemodynamic risks and benefits. METHODS: Forty-four patients...... hemodynamic parameters preserved both at rest and during exercise implying hemodynamic improvement with left ventricular unloading....

  13. Hemodynamic measurements in rat brain and human muscle using diffuse near-infrared absorption and correlation spectroscopies

    Science.gov (United States)

    Yu, Guoqiang; Durduran, Turgut; Furuya, D.; Lech, G.; Zhou, Chao; Chance, Britten; Greenberg, J. H.; Yodh, Arjun G.

    2003-07-01

    Measurement of concentration, oxygenation, and flow characteristics of blood cells can reveal information about tissue metabolism and functional heterogeneity. An improved multifunctional hybrid system has been built on the basis of our previous hybrid instrument that combines two near-infrared diffuse optical techniques to simultaneously monitor the changes of blood flow, total hemoglobin concentration (THC) and blood oxygen saturation (StO2). Diffuse correlation spectroscopy (DCS) monitors blood flow (BF) by measuring the optical phase shifts caused by moving blood cells, while diffuse photon density wave spectroscopy (DPDW) measures tissue absorption and scattering. Higher spatial resolution, higher data acquisition rate and higher dynamic range of the improved system allow us to monitor rapid hemodynamic changes in rat brain and human muscles. We have designed two probes with different source-detector pairs and different separations for the two types of experiments. A unique non-contact probe mounted on the back of a camera, which allows continuous measurements without altering the blood flow, was employed to in vivo monitor the metabolic responses in rat brain during KCl induced cortical spreading depression (CSD). A contact probe was used to measure changes of blood flow and oxygenation in human muscle during and after cuff occlusion or exercise, where the non-contact probe is not appropriate for monitoring the moving target. The experimental results indicate that our multifunctional hybrid system is capable of in vivo and non-invasive monitoring of the hemodynamic changes in different tissues (smaller tissues in rat brain, larger tissues in human muscle) under different conditions (static versus moving). The time series images of flow during CSD obtained by our technique revealed spatial and temporal hemodynamic changes in rat brain. Two to three fold longer recovery times of flow and oxygenation after cuff occlusion or exercise from calf flexors in a

  14. Relationship Between Cerebral Oxygenation and Hemodynamic and Oxygen Transport Parameters in Surgery for Acquired Heart Diseases

    Directory of Open Access Journals (Sweden)

    A. I. Lenkin

    2012-01-01

    Full Text Available Objective: to evaluate the relationship between cerebral oxygenation and hemodynamic and oxygen transport parameters in surgical correction of concomitant acquired heart diseases. Subjects and methods. Informed consent was received from 40 patients who required surgery because of concomitant (two or more acquired heart defects. During procedure, perioperative monitoring of oxygen transport and cerebral oxygenation was performed with the aid of PiCCO2 monitor (Pulsion Medical Systems, Germany and a Fore-Sight cerebral oximeter (CASMED, USA. Anesthesia was maintained with propofol and fen-tanyl, by monitoring the depth of anesthesia. Early postoperative intensive therapy was based on the protocol for early targeted correction of hemodynamic disorders. Oxygen transport and cerebral oxygenation parameters were estimated intraopera-tively and within 24 postoperative hours. A statistical analysis including evaluation of Spearman correlations was performed with the aid of SPSS 15.0. Results. During perfusion, there was a relationship between cerebral oximetry values and hemat-ocrit levels, and oxygen partial pressure in the venous blood. Furthermore, a negative correlation between cerebral oximetry values and blood lactate levels was found 30 minutes after initiation of extracorporeal circulation (EC. During the study, there was a positive correlation between cerebral oxygenation and values of cardiac index, central venous saturation, and oxygen delivery index. There was a negative relationship between cerebral oxygenation and extravascular lung water at the beginning of surgery and a correlation between cerebral oximetry values and oxygenation index by the end of the first 24 postoperative hours. Conclusion. The cerebral oxygenation values correlate -with the main determinants of oxygen transport during EC and after cardiac surgical procedures. Cerebral oximetry may be used in early targeted therapy for the surgical correction of acquired combined

  15. Characterization of Aortic Valve Closure Artifact During Outflow Tract Mapping: Correlation With Hemodynamics and Mechanical Valves.

    Science.gov (United States)

    Romero, Jorge; Ajijola, Olujimi; Shivkumar, Kalyanam; Tung, Roderick

    2017-06-01

    Premature ventricular contractions originating in the left ventricle outflow tract represent a significant subgroup of patients referred for catheter ablation. Mechanical artifacts from aortic valve leaflet motion may be observed during mapping, although the incidence and characteristics have not been reported. Twenty-eight consecutive patients with left ventricle outflow tract premature ventricular contraction were included. Electric signals recorded on the ablation catheter not coincident with atrial or ventricular depolarization were analyzed on the recording system. Correlation with invasive hemodynamic aortic pressure tracings was performed. Additionally, 4 patients with mechanical aortic valves, who underwent scar-related ventricular tachycardia ablation, were analyzed to correlate the timing of the observed artifacts with native aortic valves. Aortic valve artifact was observed while mapping within the coronary cusps in 11 patients (39%; 73% men; age, 41±25 years; left ventricular ejection fraction 49±16%) with high incidence from the left coronary cusp. This artifact was consistently observed with timing coincident with the terminal portion of the T wave. The average interval between the end of the T wave and the aortic valve artifact was 19±37 ms. The duration of the aortic valve artifact was 39±8 ms with amplitude of 0.12±0.07 mV (range, 0.06-0.36 mV). In patients referred for left ventricle outflow tract premature ventricular contraction ablation, an aortic valve closure artifact is observed in up to one third of cases during mapping within the aortic cusps. The timing of this artifact correlates with invasive hemodynamics and mechanical aortic valve artifacts. Recognition of this physiological phenomenon is useful when assigning near-field activation. © 2017 American Heart Association, Inc.

  16. Right ventricular Hemodynamic Alteration after Pulmonary Valve Replacement in Children with Congenital Heart Disease

    Directory of Open Access Journals (Sweden)

    Hamid Bigdelian

    2015-03-01

    Full Text Available Introduction:  In patients who underwent surgery to repair Tetralogy of Fallot, right ventricular dilation from pulmonary regurgitation may be result in right ventricular failure, arrhythmias and cardiac arrest. Hence, pulmonary valve replacement may be necessary to reduce right ventricular volume overload. The aim of present study was to assess the effects of pulmonary valve replacement on right ventricular function after repair of Tetralogy of Fallot.   Materials and  Method:  This retrospective study was carried out between July 2011 and October 2013 on 21 consecutive patients in Chamran Heart Center (Esfahan. The study included 13 male (61.9% and 8 female (38.1%. Cardiac magnetic resonance was performed before, 6 and 12 months after pulmonary valve replacement in all patients (Babak Imaging Center, Tehran with the 1.5 Tesla system. The main reason for surgery at Tetralogy of Fallot repaired time was Tetralogy of Fallot + Pulmonary insufficiency (17 cases and Tetralogy of Fallot + Pulmonary atresia (4 cases. Right ventricular function was assessed before and after pulmonary valve replacement with Two-dimensional echocardiography and ttest was used to evaluate follow-up data.   Results:  Right ventricular end-diastolic volume, right ventricular end- systolic volume significantly decreased (P value ˂ 0.05.Right ventricular ejection fraction had a significant increase (P value ˂ 0.05. Right ventricular mass substantially shrank after pulmonary valve replacement. Moreover, pulmonary regurgitation noticeably decreased in patients. The other hemodynamic parameter such as left ventricular ejection fraction improved but was not significant (P value= 0.79. Conclusion:  Pulmonary valve replacement can successfully restores the impaired hemodynamic function of right ventricle which is caused by direct consequence of volume unloading in patient. Pulmonary valve surgery in children with Tetralogy of Fallot who have moderate to severe pulmonary

  17. An Integrated Model of the Human Cardiopulmonary System

    National Research Council Canada - National Science Library

    Lu, K

    2002-01-01

    .... Included in the model are descriptions of atrial and ventricular mechanics, the hemodynamics of the systemic and pulmonic circulations, baroreflex control of arterial pressure, airway and lung...

  18. [Current concepts on hemodynamic support and therapy in septic shock].

    Science.gov (United States)

    Rocha, Leonardo Lima; Pessoa, Camila Menezes Souza; Corrêa, Thiago Domingos; Pereira, Adriano José; de Assunção, Murillo Santucci Cesar; Silva, Eliézer

    2015-01-01

    Severe sepsis and septic shock represent a major healthcare challenge. Much of the improvement in mortality associated with septic shock is related to early recognition combined with timely fluid resuscitation and adequate antibiotics administration. The main goals of septic shock resuscitation include intravascular replenishment, maintenance of adequate perfusion pressure and oxygen delivery to tissues. To achieve those goals, fluid responsiveness evaluation and complementary interventions - i.e. vasopressors, inotropes and blood transfusion - may be necessary. This article is a literature review of the available evidence on the initial hemodynamic support of the septic shock patients presenting to the emergency room or to the intensive care unit and the main interventions available to reach those targets, focusing on fluid and vasopressor therapy, blood transfusion and inotrope administration. Copyright © 2014 Sociedade Brasileira de Anestesiologia. Publicado por Elsevier Editora Ltda. All rights reserved.

  19. Current concepts on hemodynamic support and therapy in septic shock.

    Science.gov (United States)

    Rocha, Leonardo Lima; Pessoa, Camila Menezes Souza; Corrêa, Thiago Domingos; Pereira, Adriano José; de Assunção, Murillo Santucci Cesar; Silva, Eliézer

    2015-01-01

    Severe sepsis and septic shock represent a major healthcare challenge. Much of the improvement in mortality associated with septic shock is related to early recognition combined with timely fluid resuscitation and adequate antibiotics administration. The main goals of septic shock resuscitation include intravascular replenishment, maintenance of adequate perfusion pressure and oxygen delivery to tissues. To achieve those goals, fluid responsiveness evaluation and complementary interventions - i.e. vasopressors, inotropes and blood transfusion - may be necessary. This article is a literature review of the available evidence on the initial hemodynamic support of the septic shock patients presenting to the emergency room or to the intensive care unit and the main interventions available to reach those targets, focusing on fluid and vasopressor therapy, blood transfusion and inotrope administration. Copyright © 2014 Sociedade Brasileira de Anestesiologia. Published by Elsevier Editora Ltda. All rights reserved.

  20. Current concepts on hemodynamic support and therapy in septic shock

    Directory of Open Access Journals (Sweden)

    Leonardo Lima Rocha

    2015-10-01

    Full Text Available ABSTRACTSevere sepsis and septic shock represent a major healthcare challenge. Much of the improvement in mortality associated with septic shock is related to early recognition combined with timely fluid resuscitation and adequate antibiotics administration. The main goals of septic shock resuscitation include intravascular replenishment, maintenance of adequate perfusion pressure and oxygen delivery to tissues. To achieve those goals, fluid responsiveness evaluation and complementary interventions - i.e. vasopressors, inotropes and blood transfusion - may be necessary. This article is a literature review of the available evidence on the initial hemodynamic support of the septic shock patients presenting to the emergency room or to the intensive care unit and the main interventions available to reach those targets, focusing on fluid and vasopressor therapy, blood transfusion and inotrope administration.

  1. Radioprotection in the infirmary praxis in service of hemodynamic

    International Nuclear Information System (INIS)

    Flor, Rita de Cassia; Gelbcke, Francine Lima

    2011-01-01

    Qualitative study made in a hemodynamic service at Santa Catarina, Brazil, viewing to analyse the attitude of workers in infirmary related to the use of radioprotection measurements in interventionist procedures. A methodology of Labor Psycho dynamics was used through the observations, collective interviews and the document analysis. Totally it was realized 36 encounters, completed a total of 54 observation hours. The results have shown that the workers used defense strategies for justification the not use of some radioprotection measurements. Yet, become evident that the measurements related to the distance from the radiation source and the exposure time have not used sometimes, perhaps due to negligence. Finally, it was concluded that, some attitudes adopted by the workers referred to the lack of a continued educational program

  2. Ocular hemodynamics in patients with rhegmatogenous retinal detachment

    Directory of Open Access Journals (Sweden)

    N. H. Zavgorodnya

    2014-10-01

    Full Text Available Aim. In case of retinal detachment atrophic processes lead to irreversible loss of functions within 4–6 days, it happens on underlying low ocular blood flow. In order to evaluate the degree of violation of regional hemodynamics in patients with retinal detachment two groups of patients were examined: the main group (52 patients with rhegmatogenous retinal detachment and the control group (24 myopic patients with lattice form of peripheral chorioretinal dystrophy. Methods and results. Doppler and reography results had been compared, significant decrease of blood flow in patients with retinal detachment was found. No differences between affected and fellow eye in these patients, close negative correlation between the level of ocular blood flow and the degree of myopia in the control group. Conclusion. This demonstrates the feasibility of actions to improve regional blood flow in patients operated on for retinal detachment.

  3. Pulsatile flow effects on the hemodynamics of intracranial aneurysms.

    Science.gov (United States)

    Le, Trung B; Borazjani, Iman; Sotiropoulos, Fotis

    2010-11-01

    High-resolution numerical simulations are carried out to systematically investigate the effect of the incoming flow waveform on the hemodynamics and wall shear stress patterns of an anatomic sidewall intracranial aneurysm model. Various wave forms are constructed by appropriately scaling a typical human waveform such that the waveform maximum and time-averaged Reynolds numbers, the Womersley number (α), and the pulsatility index (PI) are systematically varied within the human physiologic range. We show that the waveform PI is the key parameter that governs the vortex dynamics across the aneurysm neck and the flow patterns within the dome. At low PI, the flow in the dome is similar to a driven cavity flow and is characterized by a quasi-stationary shear layer that delineates the parent artery flow from the recirculating flow within the dome. At high PI, on the other hand, the flow is dominated by vortex ring formation, transport across the neck, and impingement and breakdown at the distal wall of the aneurysm dome. We further show that the spatial and temporal characteristics of the wall shear stress field on the aneurysm dome are strongly correlated with the vortex dynamics across the neck. We finally argue that the ratio between the characteristic time scale of transport by the mean flow across the neck and the time scale of vortex ring formation can be used to predict for a given sidewall aneurysm model the critical value of the waveform PI for which the hemodynamics will transition from the cavity mode to the vortex ring mode.

  4. Leonardo da Vinci and the first hemodynamic observations.

    Science.gov (United States)

    Martins e Silva, J

    2008-02-01

    Leonardo da Vinci was a genius whose accomplishments and ideas come down to us today, five centuries later, with the freshness of innovation and the fascination of discovery. This brief review begins with a summary of Leonardo's life and a description of the most important works of art that he bequeathed us, and then concentrates on his last great challenge. There was a point at which Leonardo's passion for art gave way to the study of human anatomy, not only to improve his drawing but to go beyond what had been simply a representation of form to understand the underlying functioning. Among his many interests, we focus on his study of the heart and blood vessels, which he observed carefully in animals and human autopsies, and reproduced in drawings of great quality with annotations of astonishing acuteness. The experience that he had acquired from observing the flow of water in currents and around obstacles, and the conclusions that he drew concerning hydrodynamics, were central to his interpretation of the mechanisms of the heart and of blood flow, to which he devoted much of his time between 1508 and 1513. From these studies, immortalized in drawings of great clarity, come what are acknowledged to be the first hemodynamic records, in which Leonardo demonstrates the characteristics of blood flow in the aorta and great vessels and the importance of blood reflux and the formation of eddies in the sinus in aortic valve his assiduous and careful observations, and his subsequent deductions, Leonardo put forward detailed findings on hemodynamic questions that advanced technology has only recently enabled us to confirm.

  5. Circulating endothelial microparticle levels predict hemodynamic severity of pulmonary hypertension.

    Science.gov (United States)

    Amabile, Nicolas; Heiss, Christian; Real, Wendy May; Minasi, Petros; McGlothlin, Dana; Rame, Eduardo J; Grossman, William; De Marco, Teresa; Yeghiazarians, Yerem

    2008-06-01

    Circulating microparticles (MPs) are submicron membrane fragments shed from damaged or activated vascular cells. Endothelial MPs are a biological marker of dysfunctional endothelium. Vascular remodeling and endothelial dysfunction are involved in pulmonary hypertension (PH). We tested the hypothesis that circulating MPs are increased in patients with PH and that identifiable subgroups of MPs predict the hemodynamic severity of this condition progression. Patients (n = 24; age, 54 +/- 4 yr) undergoing right heart catheterization for precapillary PH without any endothelium-active vasodilator therapy participated in the study. Age- and sex-matched healthy control subjects (n = 20) were included. Endothelial (PECAM(+) [CD31(+)]/ CD41(-), VE-cadherin(+) [CD144(+)], and E-selectin(+) [CD62e(+)]), platelet (CD41(+)), leukocyte-derived (CD45(+)), and annexin V(+) MPs were measured by flow cytometry in platelet-free plasma from venous blood. Levels of circulating endothelial PECAM(+), VE-cadherin(+), E-selectin(+), and leukocyte-derived MPs, but not platelet and annexin V(+) MPs, were increased in subjects with PH compared with control subjects (P < 0.01 each). PECAM(+) and VE-cadherin(+) MP levels significantly correlated with mean pulmonary artery pressure (r = 0.92 and r = 0.87, respectively), pulmonary vascular resistance (r = 0.78 and r = 0.73), and mean right atrial pressure (r = 0.43, and r = 0.46) and correlated inversely with cardiac index (r = -0.59 and r = -0.52). These relationships were not observed for other MP subgroups, and persisted in multivariate analysis after adjustment for confounding factors. In subjects with precapillary PH, levels of circulating endothelial and leukocyte MPs were increased compared with control subjects. In addition, levels of PECAM(+) and VE-cadherin(+), but not E-selectin(+), endothelial MPs predicted hemodynamic severity of the disease.

  6. Plethyzmography in assessment of hemodynamic results of pacemaker functions programming

    Science.gov (United States)

    Wojciechowski, Dariusz; Sionek, Piotr; Peczalski, Kazimierz; Janusek, Dariusz

    2011-01-01

    The paper presents potential role of plethyzmography in optimization of heart hemodynamic function during pacemaker programming. The assessment of optimal stroke volume in patients, with implanted dual chamber pacemaker (DDD), by plethyzmography was a goal of the study. The data were collected during pacing rhythm. 20 patients (8 female and 12 male, average 77.4+/-4.6 years) with dual chamber pacemaker (DDD) and with pacing rhythm during routine pacemaker control and study tests were incorporated in the study group. Hemodynamic parameters were assessed during modification of atrio-ventricular delay (AVD) for pacing rhythm of 70 bpm and 90 bpm. The time of atrioventricular was programmed with 20 ms steps within range 100-200 ms and data were recorded with two minutes delay between two consecutive measurements. Stroke volume (SV) and cardiac output (CO) were calculated from plethyzmographic signal by using Beatscope software (TNO Holand). Highest SV calculated for given pacing rhythm was named optimal stroke volume (OSV) and consequently highest cardiac output was named maximal cardiac output (MCO). The time of atrio-ventricular delay for OSV was named optimal atrioventricular delay (OAVD). The results have showed: mean values of OAVD for 70 bpm - 152+/-33 ms and for 90 bpm -149+/-35 ms, shortening of the mean OAVD time caused by increase of pacing rate from 70 bpm to 90 bpm what resulted in statistically significant decrease of OSV with not statistically significant increase of MCO. The analysis of consecutive patients revealed three types of response to increase of pacing rhythm: 1. typical-shortening of OAVD, 2. neutral-no change of OAVD and 3.atypical-lengthening of OAVD.

  7. Optimal hemodynamic response model for functional near-infrared spectroscopy.

    Science.gov (United States)

    Kamran, Muhammad A; Jeong, Myung Yung; Mannan, Malik M N

    2015-01-01

    Functional near-infrared spectroscopy (fNIRS) is an emerging non-invasive brain imaging technique and measures brain activities by means of near-infrared light of 650-950 nm wavelengths. The cortical hemodynamic response (HR) differs in attributes at different brain regions and on repetition of trials, even if the experimental paradigm is kept exactly the same. Therefore, an HR model that can estimate such variations in the response is the objective of this research. The canonical hemodynamic response function (cHRF) is modeled by two Gamma functions with six unknown parameters (four of them to model the shape and other two to scale and baseline respectively). The HRF model is supposed to be a linear combination of HRF, baseline, and physiological noises (amplitudes and frequencies of physiological noises are supposed to be unknown). An objective function is developed as a square of the residuals with constraints on 12 free parameters. The formulated problem is solved by using an iterative optimization algorithm to estimate the unknown parameters in the model. Inter-subject variations in HRF and physiological noises have been estimated for better cortical functional maps. The accuracy of the algorithm has been verified using 10 real and 15 simulated data sets. Ten healthy subjects participated in the experiment and their HRF for finger-tapping tasks have been estimated and analyzed. The statistical significance of the estimated activity strength parameters has been verified by employing statistical analysis (i.e., t-value > t critical and p-value < 0.05).

  8. Mechanisms controlling renal hemodynamics and electrolyte excretion during amino acids

    Energy Technology Data Exchange (ETDEWEB)

    Woods, L.L.; Mizelle, H.L.; Montani, J.P.; Hall, J.E.

    1986-08-01

    Our purpose was to investigate the mechanisms by which increased plasma amino acids elevate renal blood flow (RBF) and glomerular filtration rate (GFR). Since transport of amino acids and Na is linked in the proximal tubule, the authors hypothesized that increased amino acids might stimulate proximal tubular Na reabsorption (PR/sub Na/) and thus increase RBF and GFR by a macula densa feedback mechanism. A solution of four amino acids (Ala, Ser, Gly, Pro) was infused intravenously into anesthetized dogs with normal kidneys (NK) and with kidneys in which the tubuloglomerular feedback mechanism was blunted by lowering renal artery pressure (LPK) or blocked by making the kidneys nonfiltering (NFK). In NK, RBF and GFR increased by 35 +/- 4% and 30 +/- 7% after 90 min of amino acid infusion, while PR/sub Na/ (estimated from lithium clearance) and O2 consumption increased by 31 +/- 5% and 29 +/- 5% and distal Na delivery remained relatively constant. Autoregulation of RBF and GFR in response to step deceases in renal artery pressure was impaired during amino acids in NK. The hemodynamic responses to amino acids were abolished in LPK and NFK. Infusion of the nonmetabolized -aminoisobutyric acid into NK produced changes in renal hemodynamics that were similar to the responses observed with the four metabolizable amino acids. These data are consistent with the hypothesis that elevation of plasma amino acids increases RBF and GFR by a mechanism that requires an intact macula densa feedback. Metabolism of the amino acids does not appear to be necessary for these changes to occur.

  9. Mechanisms controlling renal hemodynamics and electrolyte excretion during amino acids

    International Nuclear Information System (INIS)

    Woods, L.L.; Mizelle, H.L.; Montani, J.P.; Hall, J.E.

    1986-01-01

    Our purpose was to investigate the mechanisms by which increased plasma amino acids elevate renal blood flow (RBF) and glomerular filtration rate (GFR). Since transport of amino acids and Na + is linked in the proximal tubule, the authors hypothesized that increased amino acids might stimulate proximal tubular Na + reabsorption (PR/sub Na/) and thus increase RBF and GFR by a macula densa feedback mechanism. A solution of four amino acids (Ala, Ser, Gly, Pro) was infused intravenously into anesthetized dogs with normal kidneys (NK) and with kidneys in which the tubuloglomerular feedback mechanism was blunted by lowering renal artery pressure (LPK) or blocked by making the kidneys nonfiltering (NFK). In NK, RBF and GFR increased by 35 +/- 4% and 30 +/- 7% after 90 min of amino acid infusion, while PR/sub Na/ (estimated from lithium clearance) and O 2 consumption increased by 31 +/- 5% and 29 +/- 5% and distal Na + delivery remained relatively constant. Autoregulation of RBF and GFR in response to step deceases in renal artery pressure was impaired during amino acids in NK. The hemodynamic responses to amino acids were abolished in LPK and NFK. Infusion of the nonmetabolized α-aminoisobutyric acid into NK produced changes in renal hemodynamics that were similar to the responses observed with the four metabolizable amino acids. These data are consistent with the hypothesis that elevation of plasma amino acids increases RBF and GFR by a mechanism that requires an intact macula densa feedback. Metabolism of the amino acids does not appear to be necessary for these changes to occur

  10. Dose levels in medical staff at hemodynamics services

    Energy Technology Data Exchange (ETDEWEB)

    Almeida Junior, Airton T. de [FUNDACENTRO - Brazilian Institute for Safety and Health at Work, Belo Horizonte, MG (Brazil)]|[Centro de Desenvolvimento da Tecnologia Nuclear (CDTN), Belo Horizonte, MG (Brazil)]. E-mail: airton.almeida@fundacentro.gov.br; Alonso, Thessa C.; Nogueira, Maria do S.; Silva, Teogenes A. da [Centro de Desenvolvimento da Tecnologia Nuclear (CDTN/CNEN-MG), Belo Horizonte, MG (Brazil)]. E-mail: mnogue@cdtn.br; alonso@cdtn.br; silvata@cdtn.br

    2007-07-01

    The dose levels received by medical staff during interventional radiology are very high depending on the operational conditions and the patient trunk thickness. Dose levels could reach a factor of 30 for fluoroscopy or cine modes. The ALARA principle, that emphasizes the adoption of techniques and procedures to keep dose levels as low as reasonably achievable, should be followed to minimize the risk of radiation exposure to medical professionals. Dose reduction could be achieved by persuading the medical staff to wear protection devices (lead apron, thyroid protector, eyeglasses and gloves). Additionally, medical staff should also be persuaded that they should not be submitted to very high doses, above the acceptable limits for occupational workers. Dose levels at hemodynamics services in Minas Gerais State, Brazil, were analysed. Due to the equipment characteristics or the exam type and conditions x-ray machines were used with 70 to 120 kV, 2.5 to 699 mA and 80 to 2880s. Annual individual doses were estimated based on measured doses during a specific exam taking into account the workload. Maximum doses varied from 0.05 to 0.70 mSv per exam. The results projected for one work-year period show that all annual individual doses would be higher than the annual dose limit of 20 mSv/y with only a few values lower than 50 mSv/y. Dose levels measured at medical staff positions during hemodynamic exams showed that if the protective devices are not used professionals could be exposed to dose values higher than annual dose limits. (author)

  11. Hemodynamic Ramp Tests in Patients With Left Ventricular Assist Devices.

    Science.gov (United States)

    Uriel, Nir; Sayer, Gabriel; Addetia, Karima; Fedson, Savitri; Kim, Gene H; Rodgers, Daniel; Kruse, Eric; Collins, Keith; Adatya, Sirtaz; Sarswat, Nitasha; Jorde, Ulrich P; Juricek, Colleen; Ota, Takeyoshi; Jeevanandam, Valluvan; Burkhoff, Daniel; Lang, Roberto M

    2016-03-01

    This study tested whether combined invasive hemodynamic and echocardiographic ramp tests can help optimize patient management. Guidelines for optimizing speed and medications in continuous flow ventricular assist device (cfLVAD) patients are mainly based on expert opinion. Thirty-five cfLVAD patients (21 HeartMate II [Thoratec, Pleasanton, California] and 14 HVAD [HeartWare International, Framingham, Massachusetts]) underwent ramp tests with right heart catheterization (including central venous pressure [CVP], pulmonary artery pressure, pulmonary capillary wedge pressure [PCWP], and blood pressure) and echocardiography. Data were recorded at up to 9 speed settings. Speed changes were in steps of 400 revolutions per minute (RPM) for HeartMate II (8,000 to 12,000 RPM) and 100 RPM for HVAD (2,300 to 3,200 RPM) patients. Only 42.9% of patients had normal CVPs and PCWPs at their original RPM settings. Going from lowest to highest speeds, cardiac output improved by 0.16 ± 0.19 l/min/step (total change 1.28 ± 1.41 l/min) and PCWP decreased by 1.23 ± 0.85 mm Hg/step (total change 9.9 ± 6.5 mm Hg). CVP and systolic blood pressure did not change significantly with RPM. RPM were adjusted based on test results to achieve CVPs and PCWPs as close to normal limits as possible, which was feasible in 56% of patients. For the remainder, results indicated which type of medical management should be pursued. Use of combined hemodynamic and echocardiographic ramp tests in patients provides objective means of optimizing RPM, and has the potential to guide medical management. It remains to be tested whether this strategy has a beneficial impact on quality of life or clinical outcomes. Copyright © 2016 American College of Cardiology Foundation. Published by Elsevier Inc. All rights reserved.

  12. Hemodynamic changes by drug interaction of adrenaline with chlorpromazine.

    Science.gov (United States)

    Higuchi, Hitoshi; Yabuki, Akiko; Ishii-Maruhama, Minako; Tomoyasu, Yumiko; Maeda, Shigeru; Miyawaki, Takuya

    2014-01-01

    Adrenaline (epinephrine) is included in dental local anesthesia for the purpose of vasoconstriction. In Japan, adrenaline is contraindicated for use in patients receiving antipsychotic therapy, because the combination of adrenaline and an antipsychotic is considered to cause severe hypotension; however, there is insufficient evidence supporting this claim. The purpose of the present study was to clarify the changes in hemodynamics caused by drug interaction between adrenaline and an antipsychotic and to evaluate the safety of the combined use of adrenaline and an antipsychotic in an animal study. Male Sprague-Dawley rats were anesthetized with sodium pentobarbital. A catheter was inserted into the femoral artery to measure blood pressure and pulse rate. Rats were pretreated by intraperitoneal injection of chlorpromazine or chlorpromazine and propranolol, and after 20 minutes, saline or 1 of 3 different doses of adrenaline was administered by intraperitoneal injection. Changes in the ratio of mean arterial blood pressure and pulse rate were measured after the injection of adrenaline. Significant hypotension and tachycardia were observed after the injection of adrenaline in the chlorpromazine-pretreated rats. These effects were in a dose-dependent manner, and 100 μg/kg adrenaline induced significant hemodynamic changes. Furthermore, in the chlorpromazine and propranolol-pretreated rats, modest hypertension was induced by adrenaline, but hypotension and tachycardia were not significantly shown. Hypotension was caused by a drug interaction between adrenaline and chlorpromazine through the activation of the β-adrenergic receptor and showed a dose-dependent effect. Low-dose adrenaline similar to what might be used in human dental treatment did not result in a significant homodynamic change.

  13. Morphologic and hemodynamic analysis of paraclinoid aneurysms: ruptured versus unruptured.

    Science.gov (United States)

    Liu, Jian; Xiang, Jianping; Zhang, Ying; Wang, Yang; Li, Haiyun; Meng, Hui; Yang, Xinjian

    2014-11-01

    In order to determine the risk factors related to aneurysm rupture, we studied the aneurysms at the paraclinoid segment of the internal carotid artery by applying morphologic and hemodynamic numerical analyzes. 107 patients with 110 paraclinoid aneurysms (26 ruptured, 84 unruptured) were analyzed using computational fluid dynamics based on patient-specific three-dimensional geometrical models. A series of morphologic and hemodynamic parameters were evaluated to find the potential indicators of aneurysm rupture. Aneurysms with an irregular shape accounted for 23.1% of the ruptured group and only 8.3% of the unruptured group. The difference was statistically significant (p=0.042, χ(2) test). Ruptured paraclinoid aneurysms were found to be significantly smaller than unruptured aneurysms (p=0.041), which is different from the results of most previous studies. Energy loss (EL) and inflow concentration showed a level of statistical significance to assess the risk of rupture in paraclinoid aneurysms. By multivariate logistic regression analysis, aneurysm shape (regular or irregular), EL and inflow concentration were retained as independently significant parameters. The odds of rupture were increased by 1.65 times for a 10% increase in EL, by 4.88 times for an aneurysm with an irregular shape and by 2.91 times for an aneurysm with concentrated inflow jet. Irregular shape, larger EL and concentrated inflow jet were independently associated with the rupture status of paraclinoid aneurysms. These findings need to be further confirmed based on large multicenter and multipopulation data. Published by the BMJ Publishing Group Limited. For permission to use (where not already granted under a licence) please go to http://group.bmj.com/group/rights-licensing/permissions.

  14. Hemodynamic, ventilator, and ECG changes in pediatric patients undergoing extraction

    Directory of Open Access Journals (Sweden)

    Y K Sanadhya

    2013-01-01

    Full Text Available Background: Dental treatment induces pain anxiety and fear. This study was conducted to assess the changes in hemodynamic, ventilator, and electrocardiograph changes during extraction procedure among 12-15-year-old children and compare these changes with anxiety, fear, and pain. Materials and Methods: A purposive sample of 60 patients selected based on inclusion and exclusion criteria underwent study procedure in the dental OPD of a medical college and hospital. The anxiety, fear, and pain were recorded by dental anxiety scale, dental fear scale, and visual analogue scale, respectively, before the start of the procedure. The systolic blood pressure, diastolic blood pressure, heart rate, oxygen saturation, and electrocardiogram changes were monitored during the extraction procedure. The recording was taken four times (preinjection phase, injection, extraction, and postextraction and was analyzed. Results: At the preinjection phase the mean vales were systolic blood pressure (128 ± 11.2, diastolic blood pressure (85.7 ± 6.3, heart rate (79.7 ± 9.3, and oxygen saturation (97.9 ± 5.8. These values increased in injection phases and decreased in extraction phase and the least values were found after 10 min of procedure and this relation was significant for all parameters except oxygen saturation (P = 0.48, NS. ECG abnormalities were seen among 22 patients and were significant before and after injection of Local anesthetic (P = 0.0001, S. Conclusions: Anxiety, fear, and pain have an effect on hemodynamic, ventilator, and cardiovascular parameters during the extraction procedure and hence behavioral management has to be emphasized among children in dental clinics.

  15. Does the mesodermal derangement in Chiari Type I malformation extend to the cervical spine? Evidence from an analytical morphometric study on cervical paraspinal muscles.

    Science.gov (United States)

    Thakar, Sumit; Kurudi Siddappa, Avinash; Aryan, Saritha; Mohan, Dilip; Sai Kiran, Narayanam Anantha; Hegde, Alangar S

    2017-10-01

    OBJECTIVE The mesodermal derangement in Chiari Type I malformation (CMI) has been postulated to encompass the cervical spine. The objectives of this study were to assess the cross-sectional areas (CSAs) of cervical paraspinal muscles (PSMs) in patients with CMI without syringomyelia, compare them with those in non-CMI subjects, and evaluate their correlations with various factors. METHODS In this retrospective study, the CSAs of cervical PSMs in 25 patients were calculated on T2-weighted axial MR images and computed as ratios with respect to the corresponding vertebral body areas. These values and the cervical taper ratios were then compared with those of age- and sex-matched non-CMI subjects and analyzed with respect to demographic data and clinicoradiological factors. RESULTS Compared with the non-CMI group, the mean CSA values for the rectus capitis minor and all of the subaxial PSMs were lower in the study group, and those of the deep extensors were significantly lower (p = 0.004). The cervical taper ratio was found to be significantly higher in the study cohort (p = 0.0003). A longer duration of symptoms and a steeper cervical taper ratio were independently associated with lower CSA values for the deep extensors (p = 0.04 and p = 0.03, respectively). The presence of neck pain was associated with a lower CSA value for the deep flexors (p = 0.03). CONCLUSIONS Patients with CMI demonstrate alterations in their cervical paraspinal musculature even in the absence of coexistent syringomyelia. Their deep extensor muscles undergo significant atrophic changes that worsen with the duration of their symptoms. This could be related to a significantly steeper cervical taper ratio that their cervical cords are exposed to. Neck pain in these patients is related to atrophy of their deep flexor muscles. A steeper cervical taper ratio and alterations in the PSMs could be additional indicators for surgery in patients with CMI without syringomyelia.

  16. Loss of Toll-Like Receptor 4 Function Partially Protects against Peripheral and Cardiac Glucose Metabolic Derangements During a Long-Term High-Fat Diet.

    Directory of Open Access Journals (Sweden)

    Ellen E Jackson

    Full Text Available Diabetes is a chronic inflammatory disease that carries a high risk of cardiovascular disease. However, the pathophysiological link between these disorders is not well known. We hypothesize that TLR4 signaling mediates high fat diet (HFD-induced peripheral and cardiac glucose metabolic derangements. Mice with a loss-of-function mutation in TLR4 (C3H/HeJ and age-matched control (C57BL/6 mice were fed either a high-fat diet or normal diet for 16 weeks. Glucose tolerance and plasma insulin were measured. Protein expression of glucose transporters (GLUT, AKT (phosphorylated and total, and proinflammatory cytokines (IL-6, TNF-α and SOCS-3 were quantified in the heart using Western Blotting. Both groups fed a long-term HFD had increased body weight, blood glucose and insulin levels, as well as impaired glucose tolerance compared to mice fed a normal diet. TLR4-mutant mice were partially protected against long-term HFD-induced insulin resistance. In control mice, feeding a HFD decreased cardiac crude membrane GLUT4 protein content, which was partially rescued in TLR4-mutant mice. TLR4-mutant mice fed a HFD also had increased expression of GLUT8, a novel isoform, compared to mice fed a normal diet. GLUT8 content was positively correlated with SOCS-3 and IL-6 expression in the heart. No significant differences in cytokine expression were observed between groups, suggesting a lack of inflammation in the heart following a HFD. Loss of TLR4 function partially restored a healthy metabolic phenotype, suggesting that TLR4 signaling is a key mechanism in HFD-induced peripheral and cardiac insulin resistance. Our data further suggest that TLR4 exerts its detrimental metabolic effects in the myocardium through a cytokine-independent pathway.

  17. Endovascular management of renal transplant dysfunction secondary to hemodynamic effects related to ipsilateral femoral arteriovenous graft

    Science.gov (United States)

    Salsamendi, Jason; Pereira, Keith; Quintana, David; Bleicher, Drew; Tabbara, Marwan; Goldstein, Michael; Narayanan, Govindarajan

    2016-01-01

    Hemodialysis access options become complex in long-term treatment for patients with renal disease, while awaiting renal transplantation (RT). Once upper extremity sites are exhausted, lower extremities are used. RT is preferably in the contralateral iliac fossa, rarely ipsilateral. In current literature, RT dysfunction secondary to the hemodynamic effects of an ipsilateral femoral arteriovenous graft (AVG) has been rarely described. To our knowledge, AVG ligation is the only published technique for hemodynamic correction of an ipsilateral AVG. We present a simple, potentially reversible endovascular approach to manage the hemodynamic effects of an AVG, without potentially permanently losing future AVG access. PMID:26899147

  18. Influence of the copper nanoparticle-ceftriaxone conjugate on hemodynamic indices in rabbits in an acute experiment

    Directory of Open Access Journals (Sweden)

    P. V. Simonov

    2015-08-01

    Full Text Available An implementation of series of preclinical studies of the copper nanoparticle-ceftriaxone conjugate as a new medication with a broad spectrum of antimicrobial action for treatment of infections, particularly caused by resistant strains, is of great importance nowadays. The aim of current research was to determinate effect of studied substance on cardiovascular function in animals when administered intravenously in an acute experiment. Methods and results. The study was carried out on 8 Chinchilla rabbits with monitoring of systemic and cardiac hemodynamic indices with ‘Hewlett Packard’ Hp Viridia Component Monitoring System. It was shown that the copper nanoparticle-ceftriaxone conjugate at doses of 10–200 mg/kg did not have a negative impact on the heart rate, maximum left ventricular pressure, systolic, diastolic blood pressure, the pulse pressure, and the mean arterial pressure. Conclusion. These findings attest to the fact that the copper nanoparticle-ceftriaxone conjugate may be considered a biosafe substance in the terms of an influence on systemic and cardiac hemodynamic indices when administered intravenously to rabbits in an acute experiment.

  19. Hemodynamic effects of python neuropeptide gamma in the anesthetized python, Python regius.

    Science.gov (United States)

    Skovgaard, Nini; Galli, Gina; Taylor, Edwin W; Conlon, J Michael; Wang, Tobias

    2005-05-15

    The effects of python neuropeptide gamma (NPgamma) on hemodynamic parameters have been investigated in the anesthetized ball python (Python regius). Bolus intra-arterial injections of synthetic python NPgamma (1-300 pmol kg-1) produced a dose-dependent decrease in systemic arterial blood pressure (Psys) concomitant with increases in systemic vascular conductance (Gsys), total cardiac output and stroke volume, but only minor effects on heart rate. The peptide had no significant effect on pulmonary arterial blood pressure (Ppul) and caused only a small increase in pulmonary conductance (Gpul) at the highest dose. In the systemic circulation, the potency of the NK1 receptor-selective agonist [Sar9,Met(0(2))11] substance P was >100-fold greater than the NK2 receptor-selective agonist [betaAla8] neurokinin A-(4-10)-peptide suggesting that the python cardiovascular system is associated with a receptor that resembles the mammalian NK1 receptor more closely than the NK2 receptor. Administration of the inhibitor of nitric oxide synthesis, L-nitro-arginine-methylester (L-NAME; 150 mg kg-1), resulted in a significant (Ppython, but neither nitric oxide nor prostaglandins mediate the vasodilatory action of NPgamma.

  20. Evaluation of liver hemodynamics using SPIO-enhanced dynamic MRI. Comparison between cirrhotic liver and normal liver

    International Nuclear Information System (INIS)

    Shimada, Kotaro; Kobayashi, Hisato; Furuta, Akihiro; Nunoura, T.; Takahashi, Takahiro; Ogasawara, Nobuhiko; Akuta, Keizo

    2006-01-01

    SPIO, ferucarbotran (Resovist), which enables rapid bolus injection is well suited for the evaluation of liver hemodynamics. Our study aimed to assess the difference of hemodynamics associated with progression of chronic liver disease using SPIO-enhanced dynamic MRI. Ten patients with normal liver function, 10 patients with chronic hepatitis, and 16 patients with liver cirrhosis were examined. The MR perfusion studies were performed by 1.5T MR system with a single-shot GRE-EPI with spectral presaturation inversion recovery (SPIR) and sensitivity encoding (SENSE) technique. After the bolus injection of SPIO (0.016 ml/kg) followed by a 20 ml saline flush, 30 sequential dynamic echo planar images were obtained under the condition of 30 seconds breath hold. From the ROI set in the right lobe of the liver, time-to-signal intensity curves (TICs) were obtained. TICs were converted to time-to-R2 * curves, and the slope at hepatic arterial phase (Sa) and at portal predominant phase (Sp) were calculated by the linear regression. Sp/Sa (portal/arterial ratio) of each group was analyzed statistically. (unpaired T-test) In comparing Sp/Sa of each group, there was a significant difference between normal liver and advanced liver cirrhosis. The decrease of Sp/Sa was seen in severe cirrhosis, but this change was unclear in chronic hepatitis and mild cirrhosis. In extremely severe cirrhosis, there was a bizarre phenomenon that Sp became minus number. In conclusion, SPIO-enhanced dynamic MRI was useful to assess the difference of liver hemodynamics associated with progression of chronic liver disease. (author)

  1. A comparison of hemodynamic effects of levosimendan and dobutamine in patients undergoing mitral valve repair / replacement for severe mitral stenosis

    Directory of Open Access Journals (Sweden)

    Ravikumar Gandham

    2013-01-01

    Full Text Available Aims and Objectives: We aimed to compare the hemodynamic effects of levosimendan and dobutamine in patients undergoing mitral valve surgery on cardiopulmonary bypass (CPB. Materials and Methods: Sixty patients were divided into 2 groups of 30 each. Group-L patients received levosimendan 0.1 μg/kg/min and Group-D patients received dobutamine 5 μg/kg/min while weaning off CPB. Additional inotrope and/or vasoconstrictor were started based on hemodynamic parameters. Hemodynamic data were collected at the end and at 30 minutes after CPB, thereafter at 6, 12, 24, and 36 hours post-CPB. Mean arterial pressure (MAP, central venous pressure (CVP, heart rate (HR, cardiac index (CI, systemic vascular resistance index (SVRI, and lactate levels were measured. Results: Group-L showed increased requirement of inotropes and vasoconstrictors. The SVRI, CVP, and MAP were reduced more in Group-L. The CI was low in Group-L in the initial period when compared to Group-D. Later Group-L patients showed a statistically significant increase in CI even after 12 hrs of discontinuation of levosimendan infusion. The HR was increased more in Group-D. Lactate levels, intensive care unit stay, and duration of ventilation were similar in both groups. Conclusions: Levosimendan 0.1 μg/kg/min compared to dobutamine 5 μg/kg/min showed more vasodilation and lesser inotropic activity in patients undergoing mitral valve surgery for mitral stenosis. Levosimendan compared to dobutamine showed a statistically significant increase in CI even after 12 hrs of discontinuation. The requirement of another inotrope or vasopressor was frequent in levosimendan group.

  2. Continuous Cardiac Autonomic and Hemodynamic Responses to Isometric Exercise.

    Science.gov (United States)

    Taylor, Katrina A; Wiles, Jonathan D; Coleman, Damian D; Sharma, Rajan; Oʼdriscoll, Jamie M

    2017-08-01

    Elevated arterial blood pressure (BP) is associated with autonomic dysfunction and impaired hemodynamic control mechanisms. Isometric exercise (IE) training has been demonstrated effective at reducing BP; however, the continuous cardiovascular responses during IE are underinvestigated. We hypothesized that reflex autonomic cardiovascular control is an important mediator in reducing BP. To test our hypothesis, we investigated continuous cardiac autonomic modulation and baroreceptor reflex sensitivity (BRS) in response to IE. Twenty-five prehypertensive participants performed a single IE wall squat training session. Total power spectral density (PSD) of HR variability (HRV) and associated low-frequency (LF) and high-frequency (HF) power spectral components were recorded in absolute (ms) and normalized units (nu) before, during, and after an IE session. HR was recorded via electrocardiography and BRS via the sequence method. Continuous BP was recorded via the vascular unloading technique and stroke volume via impedance cardiography. Total peripheral resistance was calculated according to Ohm's law. During IE, there were significant reductions in HRV (P < 0.05) and BRS (P < 0.05) and significant increases in HR (P < 0.001), systolic, diastolic, and mean BP (all P < 0.001). In recovery from IE, HRV (P < 0.001), HFnu (P < 0.001), and BRS (P < 0.001) significantly increased with a significant decrease in LFnu (P < 0.001) and LF:HF ratio (P < 0.001), indicative of predominant parasympathetic over sympathetic activity. This autonomic response was associated with a significant reduction in systolic (23.2 ± 18.1 mm Hg, P < 0.001), diastolic (18.7 ± 16.9 mm Hg, P < 0.001), and mean (15.8 ± 15.5 mm Hg, P < 0.001) BP, below baseline and a significant reduction in total peripheral resistance (P < 0.001). A single IE session is associated with improved cardiac autonomic modulation and hemodynamic cardiovascular control in prehypertensive males. These acute responses may be

  3. Simultaneous Evaluation of Cerebral Hemodynamics and Light Scattering Properties of the In Vivo Rat Brain Using Multispectral Diffuse Reflectance Imaging.

    Science.gov (United States)

    Nishidate, Izumi; Mustari, Afrina; Kawauchi, Satoko; Sato, Shunichi; Sato, Manabu

    2017-05-07

    The simultaneous evaluation of cerebral hemodynamics and the light scattering properties of in vivo rat brain tissue is demonstrated using a conventional multispectral diffuse reflectance imaging system. This system is constructed from a broadband white light source, a motorized filter wheel with a set of narrowband interference filters, a light guide, a collecting lens, a video zoom lens, and a monochromatic charged-coupled device (CCD) camera. An ellipsoidal cranial window is made in the skull bone of a rat under isoflurane anesthesia to capture in vivo multispectral diffuse reflectance images of the cortical surface. Regulation of the fraction of inspired oxygen using a gas mixture device enables the induction of different respiratory states such as normoxia, hyperoxia, and anoxia. A Monte Carlo simulation-based multiple regression analysis for the measured multispectral diffuse reflectance images at nine wavelengths (500, 520, 540, 560, 570, 580, 600, 730, and 760 nm) is then performed to visualize the two-dimensional maps of hemodynamics and the light scattering properties of the in vivo rat brain.

  4. Indexes of hemodynamics in a dosage of physical activity in girls against the background of low systolic blood pressure

    Directory of Open Access Journals (Sweden)

    Levchenko V. A.

    2015-02-01

    Full Text Available Purpose: to examine the state of hemodynamics, blood oxygenation levels in girls with hypotensive type neurodystonia in a dosed physical load. Material : The study involved 59 women with hypotensive type neurodystonia aged 18-19 years and 14 healthy women the same age. Results : It was found that the girls on the background of low systolic blood pressure observed early hemodynamic response from the very first steps (25-50 W bicycle stress test in the form of increased heart rate, stroke volume, pulse pressure. At the height of the stress test in 76.27 % of girls showed a reduction in blood oxygenation indices and lengthening of the period of recovery. Conclusions : The dose of girls in physical activity with hypotension, place high demands on the cardiovascular system, the restructuring of which is accompanied by inadequate oxygen supply systems in operation, adjustment disorder, low capacity for work that requires a non-drug methods of rehabilitation in the form of regular dose of physical activity, breathing exercises .

  5. Experts' opinion on management of hemodynamics in ARDS patients: focus on the effects of mechanical ventilation

    NARCIS (Netherlands)

    Vieillard-Baron, A.; Matthay, M.; Teboul, J. L.; Bein, T.; Schultz, M.; Magder, S.; Marini, J. J.

    2016-01-01

    Acute respiratory distress syndrome (ARDS) is frequently associated with hemodynamic instability which appears as the main factor associated with mortality. Shock is driven by pulmonary hypertension, deleterious effects of mechanical ventilation (MV) on right ventricular (RV) function, and

  6. Comparison of central hemodynamic parameters for young basketball athletes and control group.

    Science.gov (United States)

    Zhang, Yahui; Fan, Xiaobing; Qi, Lin; Xu, Lisheng; Du, Chenglin

    2017-12-28

    Long-term exercise training may have negative effects on cardiovascular functions. Measurement and calculation of central hemodynamic parameters can comprehensively evaluate the cardiovascular functions. This study aims to compare the central hemodynamics between young basketball athletes and matched controls. Total 19 young long-term trained male basketball athletes and 17 matched male recreationally active controls participated. The central hemodynamic parameters such as central blood pressure, pulse pressure, heart rate (HR), augmentation index normalised to 75 bpm (AIx@HR75), augmentation index (AIx), ejection duration (ED), sub-endocardial viability ratio (SEVR) were measured, and total peripheral resistance (TPR), stroke volume (SV) and cardiac output (CO) were calculated. Non-parameter tests and t-test were used to analyse the central hemodynamic parameters between athletes and controls. HR (56 ± 5 bpm versus 79 ± 9 bpm, p parameters analysis.

  7. Children with hemodynamically significant congenital heart disease can be identified through population-based registers

    DEFF Research Database (Denmark)

    Bergman, Gunnar; Hærskjold, Ann; Stensballe, Lone Graff

    2015-01-01

    as having hemodynamically significant CHD according to the recommendations for treatment with palivizumab. CONCLUSION: It was possible to identify a subgroup of children with hemodynamically significant CHD using an epidemiological approach and an algorithm with high validity. Our results will enable well-powered......BACKGROUND: Epidemiological research is facilitated in Sweden by a history of national health care registers, making large unselected national cohort studies possible. However, for complex clinical populations, such as children with congenital heart disease (CHD), register-based studies...... is indicated as a prophylactic treatment against respiratory syncytial virus infections in children with hemodynamically significant CHD. AIM: The aim of the study reported here was to develop and validate an algorithm to identify children with hemodynamically significant CHD according to recommendations...

  8. Functionality of empirical model-based predictive analytics for the early detection of hemodynamic instabilty.

    Science.gov (United States)

    Summers, Richard L; Pipke, Matt; Wegerich, Stephan; Conkright, Gary; Isom, Kristen C

    2014-01-01

    Background. Monitoring cardiovascular hemodynamics in the modern clinical setting is a major challenge. Increasing amounts of physiologic data must be analyzed and interpreted in the context of the individual patient’s pathology and inherent biologic variability. Certain data-driven analytical methods are currently being explored for smart monitoring of data streams from patients as a first tier automated detection system for clinical deterioration. As a prelude to human clinical trials, an empirical multivariate machine learning method called Similarity-Based Modeling (“SBM”), was tested in an In Silico experiment using data generated with the aid of a detailed computer simulator of human physiology (Quantitative Circulatory Physiology or “QCP”) which contains complex control systems with realistic integrated feedback loops. Methods. SBM is a kernel-based, multivariate machine learning method that that uses monitored clinical information to generate an empirical model of a patient’s physiologic state. This platform allows for the use of predictive analytic techniques to identify early changes in a patient’s condition that are indicative of a state of deterioration or instability. The integrity of the technique was tested through an In Silico experiment using QCP in which the output of computer simulations of a slowly evolving cardiac tamponade resulted in progressive state of cardiovascular decompensation. Simulator outputs for the variables under consideration were generated at a 2-min data rate (0.083Hz) with the tamponade introduced at a point 420 minutes into the simulation sequence. The functionality of the SBM predictive analytics methodology to identify clinical deterioration was compared to the thresholds used by conventional monitoring methods. Results. The SBM modeling method was found to closely track the normal physiologic variation as simulated by QCP. With the slow development of the tamponade, the SBM model are seen to disagree while the

  9. [Transesophageal echocardiography in perioperative period guiding the decision making during hemodynamic instability due to atrial fibrillation].

    Science.gov (United States)

    Pontes, João Paulo Jordão; Dos Santos, Aline Tonin; Salgado Filho, Marcello Fonseca

    2018-03-27

    Atrial fibrillation is the most common cardiac arrhythmia, which may occur during the perioperative period and lead to hemodynamic instability due to loss of atrial systolic function. During atrial fibrillation management, electrical cardioversion is one of the therapeutic options in the presence of hemodynamic instability; however, it exposes the patient to thromboembolic event risks. Transesophageal echocardiography is a diagnostic tool for thrombi in the left atrium and left atrial appendage with high sensitivity and specificity, allowing early and safe cardioversion. The present case describes the use of transesophageal echocardiography to exclude the presence of thrombi in the left atrium and left atrial appendage in a patient undergoing non-cardiac surgery with atrial fibrillation of unknown duration and hemodynamic instability. Male patient, 74 years old, hypertensive, with scheduled abdominal surgery, who upon cardiac monitoring in the operating room showed atrial fibrillation undiagnosed in preoperative electrocardiogram, but hemodynamic stability. During surgery, the patient showed hemodynamic instability requiring norepinephrine at increasing doses, with no response to heart rate control. After the end of the surgery, transesophageal echocardiography was performed with a thorough evaluation of the left atrium and left atrial appendage and pulsed Doppler analysis of the left atrial appendage with mean velocity of 45cm.s -1 . Thrombus in the left atrium and left atrial appendage and other cardiac causes for hemodynamic instability were excluded. Therefore, electrical cardioversion was performed safely. After returning to sinus rhythm, the patient showed improvement in blood pressure levels, with noradrenaline discontinuation, extubation in the operating room, and admission to the intensive care unit. In addition to a tool for non-invasive hemodynamic monitoring, perioperative transesophageal echocardiography may be valuable in clinical decision making. In

  10. Hemodynamic and Neuropathological Analysis in Rats with Aluminum Trichloride-Induced Alzheimer's Disease

    OpenAIRE

    Chen, Szu-Ming; Fan, Chi-Chen; Chiue, Ming-Shiuan; Chou, Chi; Chen, Jyh-Horng; Hseu, Ruey-Shyang

    2013-01-01

    BACKGROUND AND AIMS: Hemodynamic normality is crucial to maintaining the integrity of cerebral vessels and, therefore, preserving the cognitive functions of Alzheimer's disease patients. This study investigates the implications of the hemodynamic changes and the neuropathological diversifications of AlCl3-induced AD. METHODS: The experimental animals were 8- to 12-wk-old male Wistar rats. The rats were randomly divided into 2 groups: a control group and a (+)control group. Food intake, water ...

  11. Radiation protection in hemodynamics work process: the look of the multidisciplinary team

    International Nuclear Information System (INIS)

    Borges, Laurete Medeiros; Klauberg, Daniela; Huhn, Andrea; Melo, Juliana Almeida Coelho de

    2014-01-01

    The study was conducted in a hemodynamics service of a public hospital in Florianopolis, SC, Brazil. Qualitative research with the participation of 13 professionals from a multidisciplinary team: doctors, technicians, technologists in radiology and nurses. The research material was extracted from the observations, semi-structured interviews and documentary analysis. The responses were grouped into three categories relating to: training of hemodynamic professionals and the perception of radiological protection in the work process; occupational exposure and safety of the professionals of Hemodynamics; and continuing education in hemodynamic service. Professionals are daily exposed to ionizing radiation, and for being long procedures, lead to high levels of exposure in workers. In hemodynamic services the risk of biological effects are cumulative, because radiodiagnostic procedures include issuing the higher doses of ionizing radiation in which the personnel exposure is critical. The workforce in the service researched mostly consists of technical professionals who reported little knowledge of radiation protection and ionizing radiation and that this issue was not addressed during their training. However, despite mention little knowledge about radiological protection, participants demonstrated understand the biological effects, especially with regard to pathologies caused by frequent exposure without protection to ionizing radiation. These professionals said they have no knowledge of the proper use of radiological protection equipment and the dosimeter, and that the institution does not provide all individual protective equipment required for the procedures performed in the hemodynamic service. Permanent education in hemodynamic service is very important part in the work process, though, cited by participants as little effectiveness in the institution, even when the professionals show interest in the area. Knowledge of the team providing hemodynamic service calls

  12. State of central hemodynamics in hypertensive patients associated with alimentary obesity evaluated by radiocardiography

    International Nuclear Information System (INIS)

    Sova, E.V.

    1986-01-01

    Hemodynamic changes were studied in hypertensive patients with and without obesity by means of radiocardiography. It was established that concomitant obesity results in deterioration of the hemodynamics characteristic of hypertensive disease. With the purpose of evaluation of the character of changes of the cardiac output and peripheral resistance in patients with excessive weight indices are employed considering the effect of body mass on the minute volume and general peripheral resistance

  13. Endothelial cell impact on smooth muscle cell properties: role of hemodynamic forces

    OpenAIRE

    Killeen, Maria T.

    2009-01-01

    The vascular endothelium is a dynamic cell monolayer located at the interface of the vessel wall and bloodstream, where it regulates the physiological effects of humoral and hemodynamic stimuli on vessel tone and remodelling. Hemodynamic forces are of particular interest and include shear stress, the frictional force generated by blood as it drags against the endothelium, and cyclic strain, transmural pressure due to the pulsatile nature of blood flow. Both forces can profoundly modulate vasc...

  14. Effects of Anesthetic Management on Early Postoperative Recovery, Hemodynamics and Pain After Supratentorial Craniotomy

    OpenAIRE

    Ayrian, Eugenia; Kaye, Alan David; Varner, Chelsia L.; Guerra, Carolina; Vadivelu, Nalini; Urman, Richard D.; Zelman, Vladimir; Lumb, Philip D.; Rosa, Giovanni; Bilotta, Federico

    2015-01-01

    Various clinical trials have assessed how intraoperative anesthetics can affect early recovery, hemodynamics and nociception after supratentorial craniotomy. Whether or not the difference in recovery pattern differs in a meaningful way with anesthetic choice is controversial. This review examines and compares different anesthetics with respect to wake-up time, hemodynamics, respiration, cognitive recovery, pain, nausea and vomiting, and shivering. When comparing inhalational anesthetics to in...

  15. Computational medical imaging and hemodynamics framework for functional analysis and assessment of cardiovascular structures.

    Science.gov (United States)

    Wong, Kelvin K L; Wang, Defeng; Ko, Jacky K L; Mazumdar, Jagannath; Le, Thu-Thao; Ghista, Dhanjoo

    2017-03-21

    Cardiac dysfunction constitutes common cardiovascular health issues in the society, and has been an investigation topic of strong focus by researchers in the medical imaging community. Diagnostic modalities based on echocardiography, magnetic resonance imaging, chest radiography and computed tomography are common techniques that provide cardiovascular structural information to diagnose heart defects. However, functional information of cardiovascular flow, which can in fact be used to support the diagnosis of many cardiovascular diseases with a myriad of hemodynamics performance indicators, remains unexplored to its full potential. Some of these indicators constitute important cardiac functional parameters affecting the cardiovascular abnormalities. With the advancement of computer technology that facilitates high speed computational fluid dynamics, the realization of a support diagnostic platform of hemodynamics quantification and analysis can be achieved. This article reviews the state-of-the-art medical imaging and high fidelity multi-physics computational analyses that together enable reconstruction of cardiovascular structures and hemodynamic flow patterns within them, such as of the left ventricle (LV) and carotid bifurcations. The combined medical imaging and hemodynamic analysis enables us to study the mechanisms of cardiovascular disease-causing dysfunctions, such as how (1) cardiomyopathy causes left ventricular remodeling and loss of contractility leading to heart failure, and (2) modeling of LV construction and simulation of intra-LV hemodynamics can enable us to determine the optimum procedure of surgical ventriculation to restore its contractility and health This combined medical imaging and hemodynamics framework can potentially extend medical knowledge of cardiovascular defects and associated hemodynamic behavior and their surgical restoration, by means of an integrated medical image diagnostics and hemodynamic performance analysis framework.

  16. The Effect of Inlet Waveforms on Computational Hemodynamics of Patient-Specific Intracranial Aneurysms

    OpenAIRE

    Xiang, J.; Siddiqui, A.H.; Meng, H.

    2014-01-01

    Due to the lack of patient-specific inlet flow waveform measurements, most computational fluid dynamics (CFD) simulations of intracranial aneurysms usually employ waveforms that are not patient-specific as inlet boundary conditions for the computational model. The current study examined how this assumption affects the predicted hemodynamics in patient-specific aneurysm geometries. We examined wall shear stress (WSS) and oscillatory shear index (OSI), the two most widely studied hemodynamic qu...

  17. Lipoprotein metabolism and its derangements

    African Journals Online (AJOL)

    Repro

    the plant sterols (phytosterols include sitosterol, campesterol and others) that are not assimilated. The pancreatic enzymes digest these dietary lipids to fatty acids and cholesterol before the entero- cyte re-assembles triglyceride and phospholipid to package into the. CM along with the absorbed cho- lesterol from dietary and ...

  18. Lack of evidence for an association between hemodynamic variables and hematoma growth in spontaneous intracerebral hemorrhage.

    Science.gov (United States)

    Jauch, Edward C; Lindsell, Christopher J; Adeoye, Opeolu; Khoury, Jane; Barsan, William; Broderick, Joseph; Pancioli, Arthur; Brott, Thomas

    2006-08-01

    Early hematoma expansion in spontaneous intracerebral hemorrhage (ICH) is associated with worse clinical outcome. We hypothesized that hemodynamic parameters are associated with the increase in hematoma volume owing to their relationship to blood vessel wall stresses. We performed a post hoc analysis of clinical and computed tomography (CT) data from patients enrolled in a prospective observational study of ICH patients presenting within 3 hours from symptom onset. Hematoma volumes were measured at hospital arrival and at 1 and 20 hours from presentation. Blood pressure and heart rate, recorded at 19 time points between presentation and 20 hours, were used to derive hemodynamic variables. Multivariable logistic-regression models were constructed to assess the relation between hemodynamic parameters and hematoma growth, adjusted for clinical covariates. From the original study, 98 patients underwent baseline and 1-hour CT scans; of these, 65 had 20-hour CT scans. Substantial hematoma growth was observed in 28% within the first hour. Of the 65 patients not undergoing surgery within 20 hours, 37% experienced hematoma growth by 20 hours. Neither baseline or peak hemodynamic parameters nor changes in hemodynamic parameters were significantly associated with hematoma growth at either 1 or 20 hours. We found no blood pressure or heart rate parameters, individually or in combination, that were associated with hematoma growth. Our data suggest the influence of hemodynamic parameters on vessel wall stress to be an unlikely target for intervention in reducing the risk of early hematoma growth in ICH.

  19. Slow spontaneous hemodynamic oscillations during sleep measured with near-infrared spectroscopy

    Science.gov (United States)

    Virtanen, Jaakko; Näsi, Tiina; Noponen, Tommi; Toppila, Jussi; Salmi, Tapani; Ilmoniemi, Risto J.

    2011-07-01

    Spontaneous cerebral hemodynamic oscillations below 100 mHz reflect the level of cerebral activity, modulate hemodynamic responses to tasks and stimuli, and may aid in detecting various pathologies of the brain. Near-infrared spectroscopy (NIRS) is ideally suited for both measuring spontaneous hemodynamic oscillations and monitoring sleep, but little research has been performed to combine these two applications. We analyzed 30 all-night NIRS-electroencephalography (EEG) sleep recordings to investigate spontaneous hemodynamic activity relative to sleep stages determined by polysomnography. Signal power of hemodynamic oscillations in the low-frequency (LF, 40-150 mHz) and very-low-frequency (VLF, 3-40 mHz) bands decreased in slow-wave sleep (SWS) compared to light sleep (LS) and rapid-eye-movement (REM) sleep. No statistically significant (p sleep in line with earlier studies with other modalities. These results increase our knowledge of the physiology of sleep, complement EEG data, and demonstrate the applicability of NIRS to studying spontaneous hemodynamic fluctuations during sleep.

  20. Evaluation of collective protection equipment in a hemodynamic room

    International Nuclear Information System (INIS)

    Casagrande, Saman; Silva, Ana Maria Marques da; Real, Jessica Villa; Luz, Renata Matos da

    2014-01-01

    Interventional radiology has high occupational dose rates. The use of personal protective equipment (PPE) and collective protection (ECP) help to reduce the dose delivered to the individuals occupationally exposed (IOE). In order to minimize the exposure of IOE's in interventionists procedures, evaluated the attenuation of the secondary radiation produced by collective protection equipment (CPE), was used a chest non-anthropomorphic phantom of polymethylmethacrylates (PMMA), with column simulator in aluminum, with variable thicknesses and kerma rate measures the air by varying the frequency tables 15 and 30 frames / s and different exposure modes. Data were acquired initially at the height of 1.25 m, using the following combinations of the ECP: (I) unshielded, (II) with plumbum display, (III) combining skirt + display. Measured at a height of 0.5 m were acquired with and without skirt. The attenuation ranged from 83.8% to 95.4% for a thickness of 25 cm. The maximum attenuation occurred with the combination of display and skirt. There was a 5 time increase in air kerma rate to be used cine display mode, when compared to the low mode. By analyzing the frequency of the frames were obtained differences up to 3 times higher for 30 frames / s, when compared with 15 frames / s. The results show the importance of using ECP in hemodynamics services, which together with the PPE, ensure adequate protection for IOEs

  1. Adrenergic Metabolic and Hemodynamic Effects of Octopamine in the Liver

    Directory of Open Access Journals (Sweden)

    Adelar Bracht

    2013-11-01

    Full Text Available The fruit extracts of Citrus aurantium (bitter orange are traditionally used as weight-loss products and as appetite suppressants. A component of these extracts is octopamine, which is an adrenergic agent. Weight-loss and adrenergic actions are always related to metabolic changes and this work was designed to investigate a possible action of octopamine on liver metabolism. The isolated perfused rat liver was used to measure catabolic and anabolic pathways and hemodynamics. Octopamine increased glycogenolysis, glycolysis, oxygen uptake, gluconeogenesis and the portal perfusion pressure. Octopamine also accelerated the oxidation of exogenous fatty acids (octanoate and oleate, as revealed by the increase in 14CO2 production derived from 14C labeled precursors. The changes in glycogenolysis, oxygen uptake and perfusion pressure were almost completely abolished by α1-adrenergic antagonists. The same changes were partly sensitive to the β-adrenergic antagonist propranolol. It can be concluded that octopamine accelerates both catabolic and anabolic processes in the liver via adrenergic stimulation. Acceleration of oxygen uptake under substrate-free perfusion conditions also means acceleration of the oxidation of endogenous fatty acids, which are derived from lipolysis. All these effects are compatible with an overall stimulating effect of octopamine on metabolism, which is compatible with its reported weight-loss effects in experimental animals.

  2. Hemodynamic Modeling of Surgically Repaired Coarctation of the Aorta.

    Science.gov (United States)

    Olivieri, Laura J; de Zélicourt, Diane A; Haggerty, Christopher M; Ratnayaka, Kanishka; Cross, Russell R; Yoganathan, Ajit P

    2011-12-01

    PURPOSE: Late morbidity of surgically repaired coarctation of the aorta includes early cardiovascular and cerebrovascular disease, shortened life expectancy, abnormal vasomodulator response, hypertension and exercise-induced hypertension in the absence of recurrent coarctation. Observational studies have linked patterns of arch remodeling (Gothic, Crenel, and Romanesque) to late morbidity, with Gothic arches having the highest incidence. We evaluated flow in native and surgically repaired aortic arches to correlate respective hemodynamic indices with incidence of late morbidity. METHODS: Three dimensional reconstructions of each remodeled arch were created from an anatomic stack of magnetic resonance (MR) images. A structured mesh core with a boundary layer was generated. Computational fluid dynamic (CFD) analysis was performed assuming peak flow conditions with a uniform velocity profile and unsteady turbulent flow. Wall shear stress (WSS), pressure and velocity data were extracted. RESULTS: The region of maximum WSS was located in the mid-transverse arch for the Crenel, Romanesque and Native arches. Peak WSS was located in the isthmus of the Gothic model. Variations in descending aorta flow patterns were also observed among the models. CONCLUSION: The location of peak WSS is a primary difference among the models tested, and may have clinical relevance. Specifically, the Gothic arch had a unique location of peak WSS with flow disorganization in the descending aorta. Our results suggest that varied patterns and locations of WSS resulting from abnormal arch remodeling may exhibit a primary effect on clinical vascular dysfunction.

  3. Effects of adenosine infusion into renal interstitium on renal hemodynamics

    International Nuclear Information System (INIS)

    Pawlowska, D.; Granger, J.P.; Knox, F.G.

    1987-01-01

    This study was designed to investigate the hemodynamic effects of exogenous adenosine in the interstitium of the rat kidney. Adenosine or its analogues were infused into the renal interstitium by means of chronically implanted capsules. In fusion of adenosine decreased glomerular filtration rate (GFR) from 0.81 +/- 0.06 to 0.37 +/- 0.06 ml/min while having no effect on renal blood flow (RBF). The metabolically stable analogue, 2-chloradenosine (2-ClAdo), decreased GFR from 0.73 +/- 0.07 to 021 +/- 0.06 ml/min. Interstitial infusion of theophylline, an adenosine receptor antagonist, completely abolished the effects of adenosine and 2-ClAdo on GFR. The distribution of adenosine, when infused into the renal interstitium, was determined using radiolabeled 5'-(N-ethyl)-carboxamidoadenosine (NECA), a metabolically stable adenosine agonist. After continuous infusion, [ 3 H]NECA was distributed throughout the kidney. The effects of NECA to reduce GFR were similar to those of adenosine and 2-ClAdo. They conclude that increased levels of adenosine in the renal interstitium markedly decrease GFR without affecting RBF in steady-state conditions. The marked effects of adenosine agonists during their infusion into the renal interstitium and the complete blockade of these effects by theophylline suggest an extracellular action of adenosine

  4. Right Ventricular Hemodynamics in Patients with Pulmonary Hypertension

    Science.gov (United States)

    Browning, James; Fenster, Brett; Hertzberg, Jean; Schroeder, Joyce

    2012-11-01

    Recent advances in cardiac magnetic resonance imaging (CMR) have allowed for characterization of blood flow in the right ventricle (RV), including calculation of vorticity and circulation, and qualitative visual assessment of coherent flow patterns. In this study, we investigate qualitative and quantitative differences in right ventricular hemodynamics between subjects with pulmonary hypertension (PH) and normal controls. Fifteen (15) PH subjects and 10 age-matched controls underwent same day 3D time resolved CMR and echocardiography. Echocardiography was used to determine right ventricular diastolic function as well as pulmonary artery systolic pressure (PASP). Velocity vectors, vorticity vectors, and streamlines in the RV were visualized in Paraview and total RV Early (E) and Atrial (A) wave diastolic vorticity was quantified. Visualizations of blood flow in the RV are presented for PH and normal subjects. The hypothesis that PH subjects exhibit different RV vorticity levels than normals during diastole is tested and the relationship between RV vorticity and PASP is explored. The mechanics of RV vortex formation are discussed within the context of pulmonary arterial pressure and right ventricular diastolic function coincident with PH.

  5. Dietary water seems to improve skin hydration without influencing hemodynamics

    Directory of Open Access Journals (Sweden)

    Federica Tomasino

    2013-06-01

    Full Text Available The various studies on the importance of water in the hydration of human skin have suggested that an increased dietary intake might positively impact the physiology of normal skin. We evaluated the consequences of increasing water intake through drinking in skin hydration in vivo. Eating habits were maintained, evaluated by a Food Frequency Questionnaire and based on total water consumption. In two groups with different total water consumption, we evaluated the impact of 2L/day water after 30 days,. This increase produced no hemodynamic changes or weight changes but an improvement in the epidermal hydration was suggested. The magnitude of the impact on skin hydration was higher in the group that regularly consumed less water, suggesting that the increase in water consumption has more beneficial effects on those individuals who habitually consume less water per day. These data are consistent with the published literature, justifying interest in looking further into this topic, in order to better understand the importance of dietary water in the context of cutaneous physiology, especially in the group of subjects with reduced consumption habits.

  6. Hemodynamics before and after bleb formation in cerebral aneurysms

    Science.gov (United States)

    Cebral, Juan R.; Radaelli, Alessandro; Frangi, Alejandro; Putman, Christopher M.

    2007-03-01

    We investigate whether blebs in cerebral aneurysms form in regions of low or high wall shear stress (WSS), and how the intraaneurysmal hemodynamic pattern changes after bleb formation. Seven intracranial aneurysms harboring well defined blebs were selected from our database and subject-specific computational models were constructed from 3D rotational angiography. For each patient, a second anatomical model representing the aneurysm before bleb formation was constructed by smoothing out the bleb. Computational fluid dynamics simulations were performed under pulsatile flow conditions for both models of each aneurysm. In six of the seven aneurysms, the blebs formed in a region of elevated WSS associated to the inflow jet impaction zone. In one, the bleb formed in a region of low WSS associated to the outflow zone. In this case, the inflow jet maintained a fairly concentrated structure all the way to the outflow zone, while in the other six aneurysms it dispersed after impacting the aneurysm wall. In all aneurysms, once the blebs formed, new flow recirculation regions were formed inside the blebs and the blebs progressed to a state of low WSS. Assuming that blebs form due to a focally damaged arterial wall, these results seem to indicate that the localized injury of the vessel wall may be caused by elevated WSS associated with the inflow jet. However, the final shape of the aneurysm is probably also influenced by the peri-aneurysmal environment that can provide extra structural support via contact with structures such as bone or dura matter.

  7. Common carotid artery hemodynamic factors in patients with cerebral infarctions.

    Science.gov (United States)

    Velcheva, Irena; Antonova, Nadia; Damianov, Petar; Dimitrov, Nikolay

    2010-01-01

    The aim of the study was to investigate the changes of the common carotid local hemodynamic factors like wall shear stress and tensile forces in 16 patients with chronic unilateral cerebral infarctions (CUCI), 58 patients with risk factors (RF) for cerebrovascular disease (CVD) and 25 healthy control subjects. The blood flow velocities (BFV), the internal diameters (D) and the vessel wall intima-media thickness (IMT) in the common carotid arteries (CCA) were recorded with color duplex sonography. Systolic (SBP) and diastolic (DBP) blood pressure were measured and mean blood pressure (MBP) was calculated by the formula of Wiggers. Whole blood viscosity (WBV) at the shear rate of 94.5 s-1 was measured on the day of the Doppler ultrasound examination with a rotational viscometer Contraves Low Shear 30. Wall shear stress (WSS), the circumferential wall tension (T) and the tensile stress tau were calculated. The main RF in the patients' groups were hypertension and hyperlipidemia. The SBP, WBV and IMT were significantly increased in the patients with UCI and RF for CVD in comparison to controls. Lower systolic WSS and tau and higher T were established in the patients with UCI. The IMT correlated with WSS and tau. The study confirms the complex influence of the changes in WBV and blood pressure for the development of carotid atherosclerosis.

  8. Mining data from hemodynamic simulations via Bayesian emulation

    Directory of Open Access Journals (Sweden)

    Nair Prasanth B

    2007-12-01

    Full Text Available Abstract Background: Arterial geometry variability is inevitable both within and across individuals. To ensure realistic prediction of cardiovascular flows, there is a need for efficient numerical methods that can systematically account for geometric uncertainty. Methods and results: A statistical framework based on Bayesian Gaussian process modeling was proposed for mining data generated from computer simulations. The proposed approach was applied to analyze the influence of geometric parameters on hemodynamics in the human carotid artery bifurcation. A parametric model in conjunction with a design of computer experiments strategy was used for generating a set of observational data that contains the maximum wall shear stress values for a range of probable arterial geometries. The dataset was mined via a Bayesian Gaussian process emulator to estimate: (a the influence of key parameters on the output via sensitivity analysis, (b uncertainty in output as a function of uncertainty in input, and (c which settings of the input parameters result in maximum and minimum values of the output. Finally, potential diagnostic indicators were proposed that can be used to aid the assessment of stroke risk for a given patient's geometry.

  9. A dimensionless parameter for classifying hemodynamics in intracranial

    Science.gov (United States)

    Asgharzadeh, Hafez; Borazjani, Iman

    2015-11-01

    Rupture of an intracranial aneurysm (IA) is a disease with high rates of mortality. Given the risk associated with the aneurysm surgery, quantifying the likelihood of aneurysm rupture is essential. There are many risk factors that could be implicated in the rupture of an aneurysm. However, the most important factors correlated to the IA rupture are hemodynamic factors such as wall shear stress (WSS) and oscillatory shear index (OSI) which are affected by the IA flows. Here, we carry out three-dimensional high resolution simulations on representative IA models with simple geometries to test a dimensionless number (first proposed by Le et al., ASME J Biomech Eng, 2010), denoted as An number, to classify the flow mode. An number is defined as the ratio of the time takes the parent artery flow transports across the IA neck to the time required for vortex ring formation. Based on the definition, the flow mode is vortex if An>1 and it is cavity if AnOSI on the human subject IA. This work was supported partly by the NIH grant R03EB014860, and the computational resources were partly provided by CCR at UB. We thank Prof. Hui Meng and Dr. Jianping Xiang for providing us the database of aneurysms and helpful discussions.

  10. Hemodynamic assessment in patients with one-and-a-half ventricle repair revealed by four-dimensional flow magnetic resonance imaging.

    Science.gov (United States)

    Uribe, Sergio; Bächler, Pablo; Valverde, Israel; Crelier, Gérard R; Beerbaum, Philipp; Tejos, Cristian; Irarrazaval, Pablo

    2013-02-01

    We report hemodynamic findings in two patients with pulmonary atresia and intact ventricular septum (PAIVS) after "one-and-a-half ventricle repair" and placement of a bidirectional Glenn shunt using four-dimensional (4D) flow magnetic resonance imaging. Quantification of flow and analysis of flow patterns revealed the hemodynamic "battle" between the right ventricle (RV) and the Glenn shunt. Moreover, with a novel approach we calculated during Glenn anastomosis the flow distribution from the superior vena cava (SVC) to the pulmonary arteries. Our results showed a highly asymmetric flow distribution, with most of the flow from the SVC toward the RV and not to the lungs. The evidence provided by 4D flow demonstrates poor efficiency of this system and suggests that both patients might benefit from adding an artificial pulmonary valve to avoid right heart failure.

  11. Thermal and hemodynamic response to whole-body cryostimulation in healthy subjects.

    Science.gov (United States)

    Zalewski, Pawel; Klawe, Jacek J; Pawlak, Joanna; Tafil-Klawe, Malgorzata; Newton, Julia

    2013-06-01

    Whole-body cryotherapy (WBC) is an increasing applied cryotherapeutic method, that involves application of a cryotherapeutic factor to stimulate the body by the means of intense hypothermia of virtually the body's entire area. This method is still not well recognized in Western Europe. However in recent years it is becoming increasingly popular in sports medicine and also in clinical application. Cryotherapeutic agents used in WBC are considered to be a strong stress stimulus which is associated with a variety of changes in functional parameters, particularly of the cardiovascular and autonomic nervous systems. However, such strong influence upon the entire body could be associated with the risk of unexpected reactions which might be dangerous for homeostasis. The present study evaluated the complex hemodynamic physiological reactions in response to WBC exposure in healthy subjects. Thirty healthy male volunteers participated. Each subject was exposed to WBC (-120°C) for 3-min. None of the participants had been exposed to such conditions previously. The research was conducted with modern and reliable measurements techniques, which assessed complex hemodynamic reactions and skin temperature changes non-invasively. All measurements were performed four times (before WBC, after WBC, WBC+3h and WBC+6h) with a Task Force Monitor (TFM - CNSystems, Medizintechnik, Gratz, Austria). Body superficial temperature was measured by infrared thermographic techniques - infra-red camera Flir P640 (Flir Systems Inc., Sweden). Our results show a significant decrease in heart rate, cardiac output, and increase in stroke volume, total peripheral resistance and baroreceptors reflex sensitivity. These changes were observed just after WBC exposure. At stages WBC+3h and WBC+6h there was observed a significant drop in baroreceptors reflex sensitivity due to increased thermogenesis. In conclusion, the present findings suggest that WBC strongly stimulates the baroreceptor cardiac reflex in

  12. Incidence and Risk Factors of Coagulation Profile Derangement After Liver Surgery: Implications for the Use of Epidural Analgesia-A Retrospective Cohort Study.

    Science.gov (United States)

    Jacquenod, Pierre; Wallon, Grégoire; Gazon, Mathieu; Darnis, Benjamin; Pradat, Pierre; Virlogeux, Victor; Farges, Olivier; Aubrun, Frédéric

    2018-04-01

    Hepatic surgery is a major abdominal surgery. Epidural analgesia may decrease the incidence of postoperative morbidities. Hemostatic disorders frequently occur after hepatic resection. Insertion or withdrawal (whether accidental or not) of an epidural catheter during coagulopathic state may cause an epidural hematoma. The aim of the study is to determine the incidence of coagulopathy after hepatectomy, interfering with epidural catheter removal, and to identify the risk factors related to coagulopathy. We performed a retrospective review of a prospective, multicenter, observational database including patients over 18 years old with a history of liver resection. Main collected data were the following: age, preexisting cirrhosis, Child-Pugh class, preoperative and postoperative coagulation profiles, extent of liver resection, blood loss, blood products transfused during surgery. International normalized ratio (INR) ≥1.5 and/or platelet count <80,000/mm defined coagulopathy according to the neuraxial anesthesia guidelines. A logistic regression analysis was performed to assess the association between selected factors and a coagulopathic state after hepatic resection. One thousand three hundred seventy-one patients were assessed. Seven hundred fifty-nine patients had data available about postoperative coagulopathy, which was observed in 53.5% [95% confidence interval, 50.0-57.1]. Maximum derangement in INR occurred on the first postoperative day, and platelet count reached a trough peak on postoperative days 2 and 3. In the multivariable analysis, preexisting hepatic cirrhosis (odds ratio [OR] = 2.49 [1.38-4.51]; P = .003), preoperative INR ≥1.3 (OR = 2.39 [1.10-5.17]; P = .027), preoperative platelet count <150 G/L (OR = 3.03 [1.77-5.20]; P = .004), major hepatectomy (OR = 2.96 [2.07-4.23]; P < .001), and estimated intraoperative blood loss ≥1000 mL (OR = 1.85 [1.08-3.18]; P = .025) were associated with postoperative coagulopathy. Coagulopathy is frequent (53

  13. The normal limits, subclinical significance, related metabolic derangements and distinct biological effects of body site-specific adiposity in relatively healthy population.

    Directory of Open Access Journals (Sweden)

    Chun-Ho Yun

    Full Text Available BACKGROUND: The accumulation of visceral adipose tissue that occurs with normal aging is associated with increased cardiovascular risks. However, the clinical significance, biological effects, and related cardiometabolic derangements of body-site specific adiposity in a relatively healthy population have not been well characterized. MATERIALS AND METHODS: In this cross-sectional study, we consecutively enrolled 608 asymptomatic subjects (mean age: 47.3 years, 27% female from 2050 subjects undergoing an annual health survey in Taiwan. We measured pericardial (PCF and thoracic peri-aortic (TAT adipose tissue volumes by 16-slice multi-detector computed tomography (MDCT (Aquarius 3D Workstation, TeraRecon, San Mateo, CA, USA and related these to clinical characteristics, body fat composition (Tanita 305 Corporation, Tokyo, Japan, coronary calcium score (CCS, serum insulin, high-sensitivity C-reactive protein (Hs-CRP level and circulating leukocytes count. Metabolic risk was scored by Adult Treatment Panel III guidelines. RESULTS: TAT, PCF, and total body fat composition all increased with aging and higher metabolic scores (all p<0.05. Only TAT, however, was associated with higher circulating leukocyte counts (ß-coef.:0.24, p<0.05, serum insulin (ß-coef.:0.17, p<0.05 and high sensitivity C-reactive protein (ß-coef.:0.24, p<0.05. These relationships persisted after adjustment in multivariable models (all p<0.05. A TAT volume of 8.29 ml yielded the largest area under the receiver operating characteristic curve (AUROC: 0.79, 95%CI: 0.74-0.83 to identify metabolic syndrome. TAT but not PCF correlated with higher coronary calcium score after adjustment for clinical variables (all p<0.05. CONCLUSION: In our study, we observe that age-related body-site specific accumulation of adipose tissue may have distinct biological effects. Compared to other adiposity measures, peri-aortic adiposity is more tightly associated with cardiometabolic risk profiles and

  14. Nature of peripheral and central hemodynamics in vibration disease of miners of Eastern Siberian coal industry

    Energy Technology Data Exchange (ETDEWEB)

    Kolesov, V.G.; Perminov, N.Kh.; Blankova, I.A.; Baldakova, V.P.

    1985-10-01

    Simultaneous influence of vibration and cold on cardiovascular system of miners of Eastern Siberia and Yakutia is investigated. Drillers subjected to vibration of manual perforators and low temperatures (minus 20 C to 11 C) of air in mines are studied. Leading clinical symptoms of this group of miners with vibration disease (VD) are polyneuropathy, acrospasm, degenerative inflammation of elbow joints and polymialgia. Study showed in VD hemodynamics of upper extremities is damaged. Measurements were made with the capillaryscope, thermometry, venous occulusion plethysmography of fingers, rheovasography of wrists, forearms and feet. Testing reveals venous stagnation and reduced capillary exchange of peripheral circulation. Among miners examined, most widespread clinical symptom was angiospasm, attacks of white or cyanotic fingers, due to VD and exposure to excessive cold. Simultaneous action of these factors facilitates a generalized spasm in the precapillary system that is manifested by increased peripheral resistance in the vascular bed, and is accompaned by a compensatory slowing of systolic ejection by the heart to prevent overfilling of vascular bed with blood. Thus, an optimal arterial pressure is maintained in miners with VD exposed to severe cold. 10 references.

  15. A Computational Study on the Relation between Resting Heart Rate and Atrial Fibrillation Hemodynamics under Exercise.

    Science.gov (United States)

    Anselmino, Matteo; Scarsoglio, Stefania; Saglietto, Andrea; Gaita, Fiorenzo; Ridolfi, Luca

    2017-01-01

    Clinical data indicating a heart rate (HR) target during rate control therapy for permanent atrial fibrillation (AF) and assessing its eventual relationship with reduced exercise tolerance are lacking. The present study aims at investigating the impact of resting HR on the hemodynamic response to exercise in permanent AF patients by means of a computational cardiovascular model. The AF lumped-parameter model was run to simulate resting (1 Metabolic Equivalent of Task-MET) and various exercise conditions (4 METs: brisk walking; 6 METs: skiing; 8 METs: running), considering different resting HR (70 bpm for the slower resting HR-SHR-simulations, and 100 bpm for the higher resting HR-HHR-simulations). To compare relative variations of cardiovascular variables upon exertion, the variation comparative index (VCI)-the absolute variation between the exercise and the resting values in SHR simulations referred to the absolute variation in HHR simulations-was calculated at each exercise grade (VCI4, VCI6 and VCI8). Pulmonary venous pressure underwent a greater increase in HHR compared to SHR simulations (VCI4 = 0.71, VCI6 = 0.73 and VCI8 = 0.77), while for systemic arterial pressure the opposite is true (VCI4 = 1.15, VCI6 = 1.36, VCI8 = 1.56). The computational findings suggest that a slower, with respect to a higher resting HR, might be preferable in permanent AF patients, since during exercise pulmonary venous pressure undergoes a slighter increase and systemic blood pressure reveals a more appropriate increase.

  16. A 1D pulse wave propagation model of the hemodynamics of calf muscle pump function.

    Science.gov (United States)

    Keijsers, J M T; Leguy, C A D; Huberts, W; Narracott, A J; Rittweger, J; van de Vosse, F N

    2015-07-01

    The calf muscle pump is a mechanism which increases venous return and thereby compensates for the fluid shift towards the lower body during standing. During a muscle contraction, the embedded deep veins collapse and venous return increases. In the subsequent relaxation phase, muscle perfusion increases due to increased perfusion pressure, as the proximal venous valves temporarily reduce the distal venous pressure (shielding). The superficial and deep veins are connected via perforators, which contain valves allowing flow in the superficial-to-deep direction. The aim of this study is to investigate and quantify the physiological mechanisms of the calf muscle pump, including the effect of venous valves, hydrostatic pressure, and the superficial venous system. Using a one-dimensional pulse wave propagation model, a muscle contraction is simulated by increasing the extravascular pressure in the deep venous segments. The hemodynamics are studied in three different configurations: a single artery-vein configuration with and without valves and a more detailed configuration including a superficial vein. Proximal venous valves increase effective venous return by 53% by preventing reflux. Furthermore, the proximal valves shielding function increases perfusion following contraction. Finally, the superficial system aids in maintaining the perfusion during the contraction phase and reduces the refilling time by 37%. © 2015 The Authors. International Journal for Numerical Methods in Biomedical Engineering published by John Wiley & Sons Ltd.

  17. Influence of endoleaks on aneurysm volume and hemodynamics after endovascular aneurysm repair

    International Nuclear Information System (INIS)

    Pitton, M.B.; Welter, B.; Schmenger, P.; Thelen, M.; Dueber, C.; Neufang, A.

    2003-01-01

    Purpose: To evaluate the aneurysm volume and the intra-aneurysmatic pressure and maximal pressure pulse (dp/dtmax) in completely excluded aneurysms and cases with endoleaks. Materials and Methods: In 36 mongrel dogs, experimental autologous aneurysms were treated with stent-grafts. All aortic side branches were ligated in 18 cases (group I) but were preserved in group II (n=18). Aneurysm volumes were calculated from CT scans before and after intervention, and from follow-up CT scans at 1 week, 6 weeks and 6 months. Finally, for hemodynamic measurements, manometer-tipped catheters were introduced into the excluded aneurysm sac (group I and II), selectively in endoleaks (group II), and intraluminally for aortic reference measurement. Systemic hypertension was induced by volume load and pharmacologic stress. Pressure curves and dp/dt were simultaneously recorded and the ratios of aneurysm pressure to systemic reference pressure calculated. Results: At follow-up, type-II, endoleaks were excluded in all cases of group I by selective angiography. In contrast, endoleaks were evident in all cases of group II. Volumetric analysis of the aneurysms showed a benefit for group I with an improved aneurysm shrinkage: ΔVolume +0.08%, -1.62% and -9.76% at 1 week, 6 weeks and 6 months follow-up (median, group I), compared to +1.43%, +0.67%, and -4.04% (group II), p [de

  18. Bench-to-bedside review: microvascular dysfunction in sepsis--hemodynamics, oxygen transport, and nitric oxide.

    Science.gov (United States)

    Bateman, Ryon M; Sharpe, Michael D; Ellis, Christopher G

    2003-10-01

    The microcirculation is a complex and integrated system that supplies and distributes oxygen throughout the tissues. The red blood cell (RBC) facilitates convective oxygen transport via co-operative binding with hemoglobin. In the microcirculation oxygen diffuses from the RBC into neighboring tissues, where it is consumed by mitochondria. Evidence suggests that the RBC acts as deliverer of oxygen and 'sensor' of local oxygen gradients. Within vascular beds RBCs are distributed actively by arteriolar tone and passively by rheologic factors, including vessel geometry and RBC deformability. Microvascular oxygen transport is determined by microvascular geometry, hemodynamics, and RBC hemoglobin oxygen saturation. Sepsis causes abnormal microvascular oxygen transport as significant numbers of capillaries stop flowing and the microcirculation fails to compensate for decreased functional capillary density. The resulting maldistribution of RBC flow results in a mismatch of oxygen delivery with oxygen demand that affects both critical oxygen delivery and oxygen extraction ratio. Nitric oxide (NO) maintains microvascular homeostasis by regulating arteriolar tone, RBC deformability, leukocyte and platelet adhesion to endothelial cells, and blood volume. NO also regulates mitochondrial respiration. During sepsis, NO over-production mediates systemic hypotension and microvascular reactivity, and is seemingly protective of microvascular blood flow.

  19. Hemodynamics in the Valsalva sinuses after transcatheter aortic valve implantation (TAVI).

    Science.gov (United States)

    Ducci, Andrea; Tzamtzis, Spyridon; Mullen, Michael J; Burriesci, Gaetano

    2013-09-01

    The study aim was to assess, in vitro, the hemodynamic modifications produced by transcatheter valves in the Valsalva sinuses, by mean of phase-resolved particle image velocimetry (PIV) measurements. Flow measurements were performed on a glass mock aortic root that included three polymeric valve leaflets, before and after the implantation of a Medtronic CoreValve device and of an Edwards SAPIEN valve. All experiments were carried out in a hydro-mechanical cardiovascular pulse duplicator system (Vivitro Superpump System SP3891) that reproduced physiologically equivalent pressures and flow rates conforming to the requirements of the standard ISO 5840:2005. The flow dynamics, before and after implantation of the two prosthetic devices, was characterized on the basis of phase-resolved velocity field and viscous shear rate measurements. Direct comparison indicated that both transcatheter valves determined a significant variation of flow during the early stages of valve opening and during valve closure. In general, the presence of the two valve implants significantly reduced the flow activity in the Valsalva sinuses, promoting regions of stagnation at their base. The reduction in flow in the Valsalva sinuses could be associated with the higher incidence of ischemic events reported after transcatheter heart valve implantation.

  20. Chronic monitoring of cortical hemodynamics in behaving, freely-moving rats using a miniaturized head-mounted optical microscope

    Science.gov (United States)

    Sigal, Iliya; Gad, Raanan; Koletar, Margaret; Ringuette, Dene; Stefanovic, Bojana; Levi, Ofer

    2016-03-01

    Growing interest within the neurophysiology community in assessing healthy and pathological brain activity in animals that are awake and freely-behaving has triggered the need for optical systems that are suitable for such longitudinal studies. In this work we report label-free multi-modal imaging of cortical hemodynamics in the somatosensory cortex of awake, freely-behaving rats, using a novel head-mounted miniature optical microscope. The microscope employs vertical cavity surface emitting lasers (VCSELs) at three distinct wavelengths (680 nm, 795 nm, and 850 nm) to provide measurements of four hemodynamic markers: blood flow speeds, HbO, HbR, and total Hb concentration, across a > 2 mm field of view. Blood flow speeds are extracted using Laser Speckle Contrast Imaging (LSCI), while oxygenation measurements are performed using Intrinsic Optical Signal Imaging (IOSI). Longitudinal measurements on the same animal are made possible over the course of > 6 weeks using a chronic window that is surgically implanted into the skull. We use the device to examine changes in blood flow and blood oxygenation in superficial cortical blood vessels and tissue in response to drug-induced absence-like seizures, correlating motor behavior with changes in blood flow and blood oxygenation in the brain.

  1. Characterization of Hemodynamics in Great Arteries of Wild-Type Mouse Using Computational Fluid Dynamics Based on Ultrasound Images.

    Science.gov (United States)

    Chen, Zhuo; Zhou, Yue; Ma, Youcai; Wang, Jingying; He, Yihua; Li, Zhian

    2016-03-01

    Hemodynamic factors in cardiovascular system are hypothesized to play a significant role in causing structural heart development. It is thus important to improve our understanding of velocity characteristics and parameters. We present such a study on wild-type mouse to characterize the vessel geometry, flow pattern, and wall shear stress in great arteries. Microultrasound imaging for small animals was used to measure blood boundary and velocity of the great arteries. Subsequently, specimens' flow boundary conditions were used for 3-dimensional reconstructions of the great artery and aortic arch dimensions, and blood flow velocity data were input into subject-specific computational fluid dynamics for modeling hemodynamics. Measurement by microultrasound imaging showed that blood velocities in the great artery and aortic arch had strong correlations with vascular sizes, whereas blood pressure had a weak trend in relation to vascular size. Wall shear stress magnitude increased when closer to arterial branches and reduced proximally in the aortic root and distally in the descending aorta, and the parameters were related to the fluid mechanics in branches in some degree. We developed a method to investigate fluid mechanics in mouse arteries, using a combination of microultrasound and computational fluid dynamics, and demonstrated its ability to reveal detailed geometric, kinematic, and fluid mechanics parameters.

  2. A hemodynamic, metabolic and histopathological study of a heterotopic auxiliary swine liver graft with portal vein arterialization.

    Science.gov (United States)

    Fernández-Rodríguez, Olga M; Ríos, Antonio; Palenciano, Carlos; Ramírez, Pablo; Navarro, José Luis; Martínez-Alarcón, Laura; Martínez, Carlos; Fuente, Teodomiro; Pons, José Antonio; Navarro, José Antonio; Majado, Maruja; Martínez, Pedro; Parrilla, Pascual

    2016-02-01

    Auxiliary heterotopic liver transplantation with portal vein arterialization (AHLT-PVA) is a model that has been hardly studied, despite its therapeutic potential. Hemodynamic and biochemical characterization was carried out during graft implantation, in a pig-to-pig model (n=15 AHLT-PVA). Furthermore a histopathological study was performed to establish microscopic alterations due to PVA. Reperfusion of the arterialized graft produced an increase in heart rate (HR) vs. baseline (P=.004) and vs. inferior vena cava clamping phase (P=.004); and a decrease in systemic vascular resistance vs. cava clamping phase (P=.021). At the end of implantation, cardiac output remained elevated (P=.001), likewise HR remained increased vs. baseline phase (P=.002). Mean arterial pressure decreased with cava clamping, but was not affected by the reperfusion of the graft, nor the skin closure. The histopathological study at 3, 10, and 21 days post-PVA revealed that functional liver structure was maintained although it is common to find foci of perilobular necrosis on day 3 (P=.049), and perilobular connective tissue proliferation at day 10 (P=.007), vs. native liver. The described arterialized liver graft model minimizes the number of vascular anastomoses vs. previously described models. It is hemodynamically and metabolically well tolerated and the double arterial vascularization of the graft does not cause significant changes in liver histology. Copyright © 2015 AEC. Publicado por Elsevier España, S.L.U. All rights reserved.

  3. Arterial Stiffness and Central Hemodynamics in Thyroidectomized Patients on Long-Term Substitution Therapy with Levothyroxine.

    Science.gov (United States)

    Laugesen, Esben; Moser, Emil; Sikjaer, Tanja; Poulsen, Per Løgstrup; Rejnmark, Lars

    2016-06-01

    Long-term levothyroxine (LT4) therapy targeting thyrotropin (TSH) suppression in hypothyroid patients treated for thyroid cancer has been associated with increased arterial stiffness and increased cardiovascular mortality. However, most patients with hypothyroidism receive LT4 therapy targeting TSH in the reference range. The long-term vascular effects of this strategy have never been evaluated. Arterial stiffness and central hemodynamics were studied in 30 thyroidectomized patients (Mage = 54.5 ± 10.2 years; 80% female) on long-term (median = 11 years; range 3-41 years) LT4 replacement therapy targeting TSH in the reference range and 30 sex- and age-matched controls. Arterial stiffness was evaluated by carotid-femoral pulse wave velocity (PWV) and central hemodynamics by pulse wave analysis using the SphygmoCor system. TSH levels were comparable in patients and controls (median = 1.99 × 10(3) IU/L [range 0.24-5.64 × 10(3) IU/L] vs. median = 2.13 × 10(3) IU/L [range 0.59-5.63 × 10(3) IU/L]; p = 0.69), but patients had higher plasma thyroxine and lower plasma triiodothyronine levels than controls (median = 108 nmol/L [range 84-149 nmol/L] vs. 86 nmol/L [range 59-141 nmol/L]; p < 0.001 and median = 1.49 nmol/L [range 1.00-2.37 nmol/L] vs. 1.62 nmol/L [range 1.18-2.09 nmol/L]; p = 0.04, respectively). PWV was not significantly higher in patients compared to controls (8.2 ± 1.9 vs. 7.9 ± 1.9 m/s, p = 0.69). Similarly, no group differences were observed in central systolic/diastolic blood pressure (120 ± 16 mmHg vs. 119 ± 12 mmHg, p = 0.77; and 80 ± 11 mmHg vs. 80 ± 10 mmHg, p = 0.98, respectively), the augmentation index (28 ± 13% vs. 29 ± 8%, p = 0.72), or the pulse pressure amplification ratio (129 ± 17% vs. 124 ± 13%, p = 0.18). Despite subtle differences in plasma levels of thyroid hormones, long-term LT4

  4. Maternal hemodynamics early in labor: a possible link with obstetric risk?

    Science.gov (United States)

    Valensise, H; Tiralongo, G M; Pisani, I; Farsetti, D; Lo Presti, D; Gagliardi, G; Basile, M R; Novelli, G P; Vasapollo, B

    2018-04-01

    To determine if hemodynamic assessment in 'low-risk' pregnant women at term with an appropriate-for-gestational age (AGA) fetus can improve the identification of patients who will suffer maternal or fetal/neonatal complications during labor. This was a prospective observational study of 77 women with low-risk term pregnancy and AGA fetus, in the early stages of labor. Hemodynamic indices were obtained using the UltraSonic Cardiac Output Monitor (USCOM ® ) system. Patients were followed until the end of labor to identify fetal/neonatal and maternal outcomes, and those which developed complications of labor were compared with those delivering without complications. Eleven (14.3%) patients had a complication during labor: in seven there was fetal distress and in four there were maternal complications (postpartum hemorrhage and/or uterine atony). Patients who developed complications during labor had lower cardiac output (5.6 ± 1.0 vs 6.7 ± 1.3 L/min, P = 0.01) and cardiac index (3.1 ± 0.6 vs 3.5 ± 0.7 L/min/m 2 , P = 0.04), and higher total vascular resistance (1195.3 ± 205.3 vs 1017.8 ± 225.6 dynes × s/cm 5 , P = 0.017) early in labor, compared with those who did not develop complications. Receiver-operating characteristics curve analysis to determine cut-offs showed cardiac output ≤ 5.8 L/min (sensitivity, 81.8%; specificity, 69.7%), cardiac index ≤ 2.9 L/min/m 2 (sensitivity, 63.6%; specificity, 76.9%) and total vascular resistance > 1069 dynes × s/cm 5 (sensitivity, 81.8%; specificity, 63.6%) to best predict maternal or fetal/neonatal complications. The study of maternal cardiovascular adaptation at the end of pregnancy could help to identify low-risk patients who may develop complications during labor. In particular, low cardiac output and high total vascular resistance are apparently associated with higher risk of fetal distress or maternal complications. Copyright © 2017 ISUOG. Published by John Wiley

  5. Effect of Varying Hemodynamic and Vascular Conditions on Fractional Flow Reserve: An In Vitro Study.

    Science.gov (United States)

    Kolli, Kranthi K; Min, James K; Ha, Seongmin; Soohoo, Hilary; Xiong, Guanglei

    2016-06-30

    The aim of this study was to investigate the impact of varying hemodynamic conditions on fractional flow reserve (ratio of pressure distal [Pd] and proximal [Pa] to stenosis under hyperemia) in an in vitro setting. Failure to achieve maximal hyperemia and the choice of hyperemic agents may have differential effects on coronary hemodynamics and, consequently, on the determination of fractional flow reserve. An in vitro flow system was developed to experimentally model the physiological coronary circulation as flow-dependent stenosis resistance in series with variable downstream resistance. Five idealized models with 30% to 70% diameter stenosis severity were fabricated using VeroClear rigid material in an Objet260 Connex printer. Mean aortic pressure was maintained at 7 levels (60-140 mm Hg) from hypotension to hypertension using a needle valve that mimicked adjustable microcirculatory resistance. A range of physiological flow rates was applied by a steady flow pump and titrated by a flow sensor. The pressure drop and the pressure ratio (Pd/Pa) were assessed for the 7 levels of aortic pressure and differing flow rates. The in vitro experimental data were coupled with pressure-flow relationships from clinical data for populations with and without myocardial infarction, respectively, to evaluate fractional flow reserve. The curve for pressure ratio and flow rate demonstrated a quadratic relationship with a decreasing slope. The absolute decrease in fractional flow reserve in the group without myocardial infarction (with myocardial infarction) was on the order of 0.03 (0.02), 0.05 (0.02), 0.07 (0.05), 0.17 (0.13) and 0.20 (0.24), respectively, for 30%, 40%, 50%, 60%, and 70% diameter stenosis, for an increase in aortic pressure from 60 to 140 mm Hg. The fractional flow reserve value, an index of physiological stenosis significance, was observed to decrease with increasing aortic pressure for a given stenosis in this idealized in vitro experiment for vascular

  6. Cerebral hemodynamics in patients with moyamoya disease, (2)

    International Nuclear Information System (INIS)

    Takeuchi, Shigekazu

    1983-01-01

    Regional cerebral blood flow (rCBF) was measured by the 133 Xe inhalation method in 19 patients with moyamoya disease aged 5 to 46 and compared with that in 17 healthy volunteers aged 7 to 67. In healthy volunteers, mean hemispheric flow values (mCBF) in the steady state decreased and cerebrovascular resistance (CVR) increased with advancing age. Most young patients showed low values of mCBF in both hemispheres in comparison with healthy volunteers. About half of the young patients showed higher values of CVR than young healthy volunteers. The distribution of rCBF showed a hyperfrontal pattern in healthy volunteers. However, in the patients, regional distribution of hemispheric flow showed a different pattern with low flow in the upper frontal region and mean flow in the posterotemporal and occipital regions. rCBF measurements were carried out during hyperventilation in five healthy volunteers and in one patient, and during 5% CO 2 inhalation in one healthy volunteer and two patients. CO 2 reactivity was uniformly present in the hemispheres of healthy volunteers. rCBF in both hemispheres was reduced by hyperventilation, more markedly in the patient than in healthy volunteers. On the other hand, in two patients, the flow was increased in the temporo-occipital regions and was decreased in the frontal region by 5% CO 2 inhalation, and mCBF was slightly increased. Postoperative rCBF measurements in 21 sides of 12 young patients indicated a gradual increase of mCBF in 14 sides of nine patients from 3 months after surgery. These results indicate that rCBF measurements by the 133 Xe inhalation method are useful in determining cerebral hemodynamics in patients with moyamoya disease, especially in children. (J.P.N.)

  7. The influence of smoking cessation on hemodynamics and arterial compliance.

    Science.gov (United States)

    Oren, Shmuel; Isakov, Irina; Golzman, Boris; Kogan, Jacob; Turkot, Svetlana; Peled, Ronit; Yosefy, Chaim

    2006-01-01

    Cigarette smoking is associated with consistent changes in small arteries and arterioles. Recently, arterial compliance was determined in smokers; however, the effect of smoking cessation on arterial compliance has not yet been investigated. The objective of the study was to assess how smoking cessation, achieved with use of behavioral and pharmacologic therapy, influences vascular compliance and arterial stiffness in smokers. In an open-label study, 60 habitual smokers were treated for 2 months with buproprion 300 mg per day and personal and group conversations in order to facilitate smoking cessation. Hemodynamic variables, including vascular compliance and augmentation index (AI), were measured twice, at the beginning of the study and after 6 months. Of the 60 smokers, 35 stopped smoking and 25 failed at the end of the 2-month treatment period. Of the 35 who were initially successful, 12 went back to smoking, and thus only 23 remained nonsmokers at the end of 6 months. Smoking cessation was accompanied by significantly lower arterial pressure and heart rate but by weight gain. Among the 23 subjects who stopped smoking for 6 months capacitive compliance (C(1)) did not change but oscillatory compliance (C(2)) rose significantly (from 5.1 +/-2.3 to 6.3 +/-3.0 p<0.01), and AI decreased significantly (from 63.1 +/-22 to 50.6 +/-17 p<0.05), whereas in smokers who still smoked after this period, both C(1) and C(2) and augmentation index did not change significantly from their basal values. The authors conclude that smoking cessation improves arterial stiffness as assessed by the augmentation index, owing mainly to increasing the small artery compliance, which is known to be an early index of endothelial damage.

  8. Predictors of hemodynamic instability during surgery for pheochromocytoma.

    Science.gov (United States)

    Kiernan, Colleen M; Du, Liping; Chen, Xi; Broome, James T; Shi, Chanjuan; Peters, Mary F; Solorzano, Carmen C

    2014-11-01

    Resection of pheochromocytoma is often associated with hemodynamic instability (HDI). We examined patient and tumor factors that may influence HDI. The effect of pretreatment with nonselective α blockade phenoxybenzamine (PXB) versus selective α blockade on HDI and outcomes was also evaluated. The records of 91 patients who underwent adrenalectomy between 2002 and 2013 were retrospectively reviewed. HDI was determined by number of intraoperative episodes of systolic blood pressure (SBP) > 200 mmHg, those greater than or less than 30 % of baseline, heart rate > 110 bpm, and the need for postoperative vasopressors. Fishers exact, t test and regressions were performed. Among 91 patients, 78 % received PXB, 18 % selective α blockade and 4 % no adrenergic blockade. Patient demographics, tumor factors and surgical approach were similar among the blockade groups. On multivariate analysis, increasing tumor size was associated with a significant rise in the number of episodes of SBP > 30 % [rate ratio (RR) 1.40] and an increased postoperative vasopressor requirement [odds ratio (OR) 1.23]. Open adrenalectomy and use of selective blockade were associated with an increased number of episodes of SBP > 200 mmHg (RR 27.8 and RR 20.9, respectively). Open adrenalectomy was also associated with increased readmissions (OR 12.3), complications (OR 5.6), use of postoperative vasopressors (OR 4.4) and hospital stay (4.6 days longer). There were no differences in other HDI measurements or postoperative outcomes among the blockade groups. Tumor size, open adrenalectomy, and type of α blockade were associated with intraoperative HDI during pheochromocytoma resection. Selective blockade was associated with significantly more episodes of intraoperative hypertension but no perioperative adverse outcomes.

  9. Microcirculatory blood flow during cardiac arrest and cardiopulmonary resuscitation does not correlate with global hemodynamics: an experimental study.

    Science.gov (United States)

    Krupičková, Petra; Mlček, Mikuláš; Huptych, Michal; Mormanová, Zuzana; Bouček, Tomáš; Belza, Tomáš; Lacko, Stanislav; Černý, Miloš; Neužil, Petr; Kittnar, Otomar; Linhart, Aleš; Bělohlávek, Jan

    2016-06-08

    Current research highlights the role of microcirculatory disorders in post-cardiac arrest patients. Affected microcirculation shows not only dissociation from systemic hemodynamics but also strong connection to outcome of these patients. However, only few studies evaluated microcirculation directly during cardiac arrest (CA) and cardiopulmonary resuscitation (CPR). The aim of our experimental study in a porcine model was to describe sublingual microcirculatory changes during CA and CPR using recent videomicroscopic technology and provide a comparison to parameters of global hemodynamics. Cardiac arrest was induced in 18 female pigs (50 ± 3 kg). After 3 min without treatment, 5 min of mechanical CPR followed. Continuous hemodynamic monitoring including systemic blood pressure and carotid blood flow was performed and blood lactate was measured at the end of baseline and CPR. Sublingual microcirculation was assessed by the Sidestream Dark Field (SDF) technology during baseline, CA and CPR. Following microcirculatory parameters were assessed off-line separately for capillaries (≤20 µm) and other vessels: total and perfused vessel density (TVD, PVD), proportion of perfused vessels (PPV), microvascular flow index (MFI) and heterogeneity index (HI). In comparison to baseline the CA small vessel microcirculation was only partially preserved: TVD 15.64 (13.59-18.48) significantly decreased to 12.51 (10.57-13.98) mm/mm(2), PVD 15.57 (13.56-17.80) to 5.53 (4.17-6.60) mm/mm(2), PPV 99.64 (98.05-100.00) to 38.97 (27.60-46.29) %, MFI 3.00 (3.00-3.08) to 1.29 (1.08-1.58) and HI increased from 0.08 (0.00-0.23) to 1.5 (0.71-2.00), p = 0.0003 for TVD and CPR in small vessels reached 59-85 % of the baseline values: TVD 13.33 (12.11-15.11) mm/mm(2), PVD 9.34 (7.34-11.52) mm/mm(2), PPV 72.34 (54.31-87.87) %, MFI 2.04 (1.58-2.42), HI 0.65 (0.41-1.07). The correlation between microcirculation and global hemodynamic parameters as well as to lactate was only weak to

  10. [Intraoperative goal directed hemodynamic therapy in noncardiac surgery: a systematic review and meta-analysis].

    Science.gov (United States)

    Ripollés, Javier; Espinosa, Angel; Martínez-Hurtado, Eugenio; Abad-Gurumeta, Alfredo; Casans-Francés, Rubén; Fernández-Pérez, Cristina; López-Timoneda, Francisco; Calvo-Vecino, José María

    2016-01-01

    The goal directed hemodynamic therapy is an approach focused on the use of cardiac output and related parameters as end-points for fluids and drugs to optimize tissue perfusion and oxygen delivery. Primary aim: To determine the effects of intraoperative goal directed hemodynamic therapy on postoperative complications rates. A meta-analysis was carried out of the effects of goal directed hemodynamic therapy in adult noncardiac surgery on postoperative complications and mortality using Preferred Reporting Items for Systematic Reviews and Meta-Analyses methodology. A systematic search was performed in Medline PubMed, Embase, and the Cochrane Library (last update, October 2014). Inclusion criteria were randomized clinical trials in which intraoperative goal directed hemodynamic therapy was compared to conventional fluid management in noncardiac surgery. Exclusion criteria were trauma and pediatric surgery studies and that using pulmonary artery catheter. End-points were postoperative complications (primary) and mortality (secondary). Those studies that fulfilled the entry criteria were examined in full and subjected to quantifiable analysis, predefined subgroup analysis (stratified by type of monitor, therapy, and hemodynamic goal), and predefined sensitivity analysis. 51 RCTs were initially identified, 24 fulfilling the inclusion criteria. 5 randomized clinical trials were added by manual search, resulting in 29 randomized clinical trials in the final analysis, including 2654 patients. A significant reduction in complications for goal directed hemodynamic therapy was observed (RR: 0.70, 95% CI: 0.62-0.79, p<0.001). No significant decrease in mortality was achieved (RR: 0.76, 95% CI: 0.45-1.28, p=0.30). Quality sensitive analyses confirmed the main overall results. Intraoperative goal directed hemodynamic therapy with minimally invasive monitoring decreases postoperative complications in noncardiac surgery, although it was not able to show a significant decrease in

  11. Intraoperative goal directed hemodynamic therapy in noncardiac surgery: a systematic review and meta-analysis

    Directory of Open Access Journals (Sweden)

    Javier Ripollés

    Full Text Available Abstract Background: The goal directed hemodynamic therapy is an approach focused on the use of cardiac output and related parameters as end-points for fluids and drugs to optimize tissue perfusion and oxygen delivery. Primary aim: To determine the effects of intraoperative goal directed hemodynamic therapy on postoperative complications rates. Methods: A meta-analysis was carried out of the effects of goal directed hemodynamic therapy in adult noncardiac surgery on postoperative complications and mortality using Preferred Reporting Items for Systematic Reviews and Meta-Analyses methodology. A systematic search was performed in Medline PubMed, Embase, and the Cochrane Library (last update, October 2014. Inclusion criteria were randomized clinical trials in which intraoperative goal directed hemodynamic therapy was compared to conventional fluid management in noncardiac surgery. Exclusion criteria were trauma and pediatric surgery studies and that using pulmonary artery catheter. End-points were postoperative complications (primary and mortality (secondary. Those studies that fulfilled the entry criteria were examined in full and subjected to quantifiable analysis, predefined subgroup analysis (stratified by type of monitor, therapy, and hemodynamic goal, and predefined sensitivity analysis. Results: 51 RCTs were initially identified, 24 fulfilling the inclusion criteria. 5 randomized clinical trials were added by manual search, resulting in 29 randomized clinical trials in the final analysis, including 2654 patients. A significant reduction in complications for goal directed hemodynamic therapy was observed (RR: 0.70, 95% CI: 0.62-0.79, p < 0.001. No significant decrease in mortality was achieved (RR: 0.76, 95% CI: 0.45-1.28, p = 0.30. Quality sensitive analyses confirmed the main overall results. Conclusions: Intraoperative goal directed hemodynamic therapy with minimally invasive monitoring decreases postoperative complications in noncardiac

  12. Intraoperative goal directed hemodynamic therapy in noncardiac surgery: a systematic review and meta-analysis.

    Science.gov (United States)

    Ripollés, Javier; Espinosa, Angel; Martínez-Hurtado, Eugenio; Abad-Gurumeta, Alfredo; Casans-Francés, Rubén; Fernández-Pérez, Cristina; López-Timoneda, Francisco; Calvo-Vecino, José María

    2016-01-01

    The goal directed hemodynamic therapy is an approach focused on the use of cardiac output and related parameters as end-points for fluids and drugs to optimize tissue perfusion and oxygen delivery. Primary aim: To determine the effects of intraoperative goal directed hemodynamic therapy on postoperative complications rates. A meta-analysis was carried out of the effects of goal directed hemodynamic therapy in adult noncardiac surgery on postoperative complications and mortality using Preferred Reporting Items for Systematic Reviews and Meta-Analyses methodology. A systematic search was performed in Medline PubMed, Embase, and the Cochrane Library (last update, October 2014). Inclusion criteria were randomized clinical trials in which intraoperative goal directed hemodynamic therapy was compared to conventional fluid management in noncardiac surgery. Exclusion criteria were trauma and pediatric surgery studies and that using pulmonary artery catheter. End-points were postoperative complications (primary) and mortality (secondary). Those studies that fulfilled the entry criteria were examined in full and subjected to quantifiable analysis, predefined subgroup analysis (stratified by type of monitor, therapy, and hemodynamic goal), and predefined sensitivity analysis. 51 RCTs were initially identified, 24 fulfilling the inclusion criteria. 5 randomized clinical trials were added by manual search, resulting in 29 randomized clinical trials in the final analysis, including 2654 patients. A significant reduction in complications for goal directed hemodynamic therapy was observed (RR: 0.70, 95% CI: 0.62-0.79, p<0.001). No significant decrease in mortality was achieved (RR: 0.76, 95% CI: 0.45-1.28, p=0.30). Quality sensitive analyses confirmed the main overall results. Intraoperative goal directed hemodynamic therapy with minimally invasive monitoring decreases postoperative complications in noncardiac surgery, although it was not able to show a significant decrease in

  13. Hemodynamic volumetry using transpulmonary ultrasound dilution (TPUD) technology in a neonatal animal model.

    Science.gov (United States)

    Vrancken, Sabine L; van Heijst, Arno F; Hopman, Jeroen C; Liem, Kian D; van der Hoeven, Johannes G; de Boode, Willem P

    2015-10-01

    To analyze changes in cardiac output and hemodynamic volumes using transpulmonary ultrasound dilution (TPUD) in a neonatal animal model under different hemodynamic conditions. 7 lambs (3.5-8.3 kg) under general anesthesia received arterial and central venous catheters. A Gore-Tex(®) shunt was surgically inserted between the descending aorta and the left pulmonary artery to mimic a patent ductus arteriosus. After shunt opening and closure, induced hemorrhagic hypotension (by repetitive blood withdrawals) and repetitive volume challenges, the following parameters were assessed using TPUD: cardiac output, active circulating volume index (ACVI), central blood volume index (CBVI) and total end-diastolic volume index (TEDVI). 27 measurement sessions were analyzed. After shunt opening, there was a significant increase in TEDVI and a significant decrease in cardiac output with minimal change in CBVI and ACVI. With shunt closure, these results reversed. After progressive hemorrhage, cardiac output and all volumes decreased significantly, except for ACVI. Following repetitive volume resuscitation, cardiac output increased and all hemodynamic volumes increased significantly. Correlations between changes in COufp and changes in hemodynamic volumes (ACVI 0.83; CBVI 0.84 and TEDVI 0.78 respectively) were (slightly) better than between changes in COufp and changes in heart rate (0.44) and central venous pressure (0.7). Changes in hemodynamic volumes using TPUD were as expected under different conditions. Hemodynamic volumetry using TPUD might be a promising technique that has the potential to improve the assessment and interpretation of the hemodynamic status in critically ill newborns and children.

  14. Hemodynamic and radionuclide effects of acute captopril therapy for heart failure: changes in left and right ventricular volumes and function at rest and during exercise

    International Nuclear Information System (INIS)

    Massie, B.; Kramer, B.L.; Topic, N.; Henderson, S.G.

    1982-01-01

    Although the resting hemodynamic effects of captopril in congestive heart failure are known, little information is available about the hemodynamic response to captopril during exercise or about changes in noninvasive measurements of the size and function of both ventricles. In this study, 14 stable New York Heart Association class III patients were given 25 mg of oral captopril. Rest and exercise hemodynamic measurements and blood pool scintigrams were performed simultaneously before and 90 minutes after captopril. The radionuclide studies were analyzed for left and right ventricular end-diastolic volumes, end-systolic volumes, ejection fractions and pulmonary blood volume. The primary beneficial responses at rest were decreases in left and right ventricular end-diastolic volumes from 388 +/- 81 to 350 +/- 77 ml and from 52 +/- 26 to 43 +/- 20 volume units, respectively, and in their corresponding filling pressures, from 24 +/- 10 to 17 +/- 9 mm Hg and 10 +/- 5 to 6 +/- 5 mm Hg. Although stroke volume did not increase significantly, both left and right ventricular ejection fractions increased slightly, from 19 +/- 6% to 22+/- 5% and from 25 +/- 9% to 29 +/- 11%, respectively. During exercise, similar changes were noted in both hemodynamic and radionuclide indexes. This, in patients with moderate symptomatic limitation from chronic heart failure, captopril predominantly reduces ventricular volume and filling pressure, with a less significant effect on cardiac output. These effects persist during exercise, when systemic vascular resistance is already very low. Radionuclide techniques are valuable in assessing the drug effect in these subjects, particularly when ventricular volumes are also measured

  15. The Value of Quality Improvement Process in the Detection and Correction of Common Errors in Echocardiographic Hemodynamic Parameters in a Busy Echocardiography Laboratory.

    Science.gov (United States)

    Fanari, Zaher; Choudhry, Usman I; Reddy, Vivek K; Eze-Nliam, Chete; Hammami, Sumaya; Kolm, Paul; Weintraub, William S; Marshall, Erik S

    2015-12-01

    Accurate assessment of cardiac structures, ventricular function, and hemodynamics is essential for any echocardiographic laboratory. Quality improvement (QI) processes described by the American Society of Echocardiography (ASE) and the Intersocietal Commission (IAC) should be instrumental in reaching this goal. All patients undergoing transthoracic echocardiogram (TTE) followed by cardiac catheterization within 24 hours at Christiana Care Health System in 2011 and 2012 were identified, with 126 and 133 cases, respectively. Hemodynamic parameters of diastolic function and pulmonary artery systolic pressure (PASP) on TTE correlated poorly with catheterization in 2011. An educational process was developed and implemented at quarterly QI meetings based on ASE and IAC recommendations to target frequently encountered errors and provide methods for improved performance. The hemodynamic parameters were then reexamined in 2012 postintervention. Following the QI process, there was significant improvement in the correlation between invasive and echocardiographic hemodynamic measurements in both systolic and diastolic function, and PASP. This reflected in significant better correlations between echo and cath LVEF [R = 0.88, ICC = 0.87 vs. R = 0.85, ICC = 0.85; P < 0.001], average E/E' and of left ventricle end-diastolic pressure (LVEDP) [R = 0.62 vs. R = 0.09, P = 0.006] and a better correlation for PASP [R = 0.77, ICC = 0.77 vs. R = 0.30, ICC = 0.31; P = 0.05] in 2012 compared to 2011. The QI process, as recommended by ASE and IAC, can allow for identification as well as rectification of quality issues in a large regional academic medical center hospital. © 2015, Wiley Periodicals, Inc.

  16. On-demand endoscopic CO2 insufflation with feedback pressure regulation during natural orifice transluminal endoscopic surgery (NOTES) peritoneoscopy induces minimal hemodynamic and respiratory changes.

    Science.gov (United States)

    Navarro-Ripoll, Ricard; Martínez-Pallí, Graciela; Guarner-Argente, Carlos; Córdova, Henry; Martínez-Zamora, Maria Angels; Comas, Jaume; Rodríguez de Miguel, Cristina; Beltrán, Mireia; Rodríguez-D'Jesús, Antonio; Hernández-Cera, Clara; Llach, Josep; Balust, Jaume; Fernández-Esparrach, Glòria

    2012-08-01

    Endoscopic insufflation has been associated with marked increase in intra-abdominal pressure (IAP) and hemodynamic and respiratory changes during transgastric surgery. To investigate the hemodynamic and respiratory effects during intraperitoneal cavity exploration through 3 different natural orifice transluminal endoscopic surgery (NOTES) access locations compared with laparoscopy. Survival experiments using 40 female pigs randomized to transgastric, transcolonic, transvaginal, and laparoscopic peritoneoscopy. On-demand endoscopic insufflation of CO(2) with feedback pressure regulation was used in NOTES with a maximum pressure of 14 mm Hg. In the laparoscopy group, the IAP was maintained at 14 mm Hg. NOTES procedures were performed by an endoscopist (with the assistance of a gynecologist in the transvaginal group and a second endoscopist in the transgastric and transrectal groups) and laparoscopy by 2 surgeons. Invasive hemodynamic and respiratory data. Blood samples were drawn for gas analyses. All experiments except one in the transrectal group were completed. The IAP was significantly lower in all NOTES groups compared with the laparoscopy group. A significant increase in mean systemic arterial blood pressure was observed in the laparoscopy group at 15 and 30 minutes of intraperitoneal cavity exploration, but it remained unchanged during all NOTES procedures. An increase in airway pressures was observed at 15 and 30 minutes of peritoneoscopy in the animals undergoing laparoscopy, whereas those parameters remained unchanged in the NOTES groups. The laparoscopy group showed a significant impairment in pulmonary gas exchange (decrease in Pao(2), increase in Paco(2), and decrease in arterial pH) after 30 minutes of peritoneoscopy, whereas only a slight increase in Paco(2) was observed in the transrectal and transvaginal groups. Healthy animal model. On-demand endoscopic insufflation of CO(2) with feedback pressure regulation can minimize the risk of hemodynamic and

  17. Effects of lidocaine and magnesium sulfate in attenuating hemodynamic response to tracheal intubation: single-center, prospective, double-blind, randomized study.

    Science.gov (United States)

    Mendonça, Fabricio Tavares; de Queiroz, Lucas Macedo da Graça Medeiros; Guimarães, Cristina Carvalho Rolim; Xavier, Alexandre Cordeiro Duarte

    Hemodynamic response to airway stimuli is a common phenomenon and its management is important to reduce the systemic repercussions. The objective of this study is to compare the efficacy of intravenous magnesium sulfate versus lidocaine on this reflex hemodynamics after laryngoscopy and tracheal intubation. This single-center, prospective, double-blind, randomized study evaluated 56 patients ASA 1 or 2, aged 18-65 years, scheduled for elective surgeries under general anesthesia with intubation. The patients were allocated into two groups: Group F received 30mg·kg -1 of magnesium sulphate and Group L, 2mg·kg -1 of lidocaine, continuous infusion, immediately before the anesthetic induction. Blood pressure (BP), heart rate (HR), and bispectral index (BIS) were measured in both groups at six different times related to administration of the study drugs. In both groups there was an increase in HR and BP after laryngoscopy and intubation, compared to baseline. Group M showed statistically significant increase in the values of systolic and diastolic blood pressure after intubation, which was clinically unimportant. There was no difference in the BIS values between groups. Among patients receiving magnesium sulfate, three (12%) had high blood pressure versus only one among those receiving lidocaine (4%), with no statistical difference. Magnesium sulfate and lidocaine have good efficacy and safety for hemodynamic management in laryngoscopy and intubation. Copyright © 2016 Sociedade Brasileira de Anestesiologia. Published by Elsevier Editora Ltda. All rights reserved.

  18. Quantitative assessment of hemodynamic and structural characteristics of in vivo brain tissue using total diffuse reflectance spectrum measured in a non-contact fashion.

    Science.gov (United States)

    Song, Yinchen; Garcia, Sarahy; Frometa, Yisel; Ramella-Roman, Jessica C; Soltani, Mohammad; Almadi, Mohamed; Riera, Jorge J; Lin, Wei-Chiang

    2017-01-01

    Here we present a new methodology that investigates the intrinsic structural and hemodynamic characteristics of in vivo brain tissue, in a non-contact fashion, and can be easily incorporated in an intra-operative environment. Within this methodology, relative total diffuse reflectance spectra (R TD (λ)) were acquired from targets using a hybrid spectroscopy imaging system. A spectral interpretation algorithm was subsequently applied to R TD (λ) to retrieve optical properties related to the compositional and structural characteristics of each target. Estimation errors of the proposed methodology were computationally evaluated using a Monte Carlo simulation model for photon migration under various conditions. It was discovered that this new methodology could handle moderate noise and achieve very high accuracy, but only if the refractive index of the target is known. The accuracy of the technique was also validated using a series of tissue phantom studies, and consistent and accurate estimates of μ s '(λ)/μ a (λ) were obtained from all the phantoms tested. Finally, a small-scale animal study was conducted to demonstrate the clinical utility of the reported method, wherein a forepaw stimulation model was utilized to induce transient hemodynamic responses in somatosensory cortices. With this approach, significant stimulation-related changes (p < 0.001) in cortical hemodynamic and structural characteristics were successfully measured.

  19. Central and peripheral hemodynamics in exercising humans: leg vs arm exercise.

    Science.gov (United States)

    Calbet, J A L; González-Alonso, J; Helge, J W; Søndergaard, H; Munch-Andersen, T; Saltin, B; Boushel, R

    2015-12-01

    In humans, arm exercise is known to elicit larger increases in arterial blood pressure (BP) than leg exercise. However, the precise regulation of regional vascular conductances (VC) for the distribution of cardiac output with exercise intensity remains unknown. Hemodynamic responses were assessed during incremental upright arm cranking (AC) and leg pedalling (LP) to exhaustion (Wmax) in nine males. Systemic VC, peak cardiac output (Qpeak) (indocyanine green) and stroke volume (SV) were 18%, 23%, and 20% lower during AC than LP. The mean BP, the rate-pressure product and the associated myocardial oxygen demand were 22%, 12%, and 14% higher, respectively, during maximal AC than LP. Trunk VC was reduced to similar values at Wmax. At Wmax, muscle mass-normalized VC and fractional O2 extraction were lower in the arm than the leg muscles. However, this was compensated for during AC by raising perfusion pressure to increase O2 delivery, allowing a similar peak VO2 per kg of muscle mass in both extremities. In summary, despite a lower Qpeak during arm cranking the cardiovascular strain is much higher than during leg pedalling. The adjustments of regional conductances during incremental exercise to exhaustion depend mostly on the relative intensity of exercise and are limb-specific. © 2015 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

  20. Arterial-venous network formation during brain vascularization involves hemodynamic regulation of chemokine signaling.

    Science.gov (United States)

    Bussmann, Jeroen; Wolfe, Scot A; Siekmann, Arndt F

    2011-05-01

    During angiogenic sprouting, newly forming blood vessels need to connect to the existing vasculature in order to establish a functional circulatory loop. Previous studies have implicated genetic pathways, such as VEGF and Notch signaling, in controlling angiogenesis. We show here that both pathways similarly act during vascularization of the zebrafish central nervous system. In addition, we find that chemokine signaling specifically controls arterial-venous network formation in the brain. Zebrafish mutants for the chemokine receptor cxcr4a or its ligand cxcl12b establish a decreased number of arterial-venous connections, leading to the formation of an unperfused and interconnected blood vessel network. We further find that expression of cxcr4a in newly forming brain capillaries is negatively regulated by blood flow. Accordingly, unperfused vessels continue to express cxcr4a, whereas connection of these vessels to the arterial circulation leads to rapid downregulation of cxcr4a expression and loss of angiogenic characteristics in endothelial cells, such as filopodia formation. Together, our findings indicate that hemodynamics, in addition to genetic pathways, influence vascular morphogenesis by regulating the expression of a proangiogenic factor that is necessary for the correct pathfinding of sprouting brain capillaries.

  1. Cardiovascular Reactivity: its Association with Physical Activity, and Some Hemodynamic and Anthropometric Variables

    Directory of Open Access Journals (Sweden)

    Milagros Lisset León Regal

    2016-09-01

    Full Text Available Background: several studies show the influence of physical activity as a protective factor of the cardiovascular system. New evidence forcorroborating this are needed to ensure the prevention of cardiovascular disease. Objective: to determine the relationship between cardiovascular hyperactivity, physical activity and some homodynamic and anthropometric variables in normotensive individuals. Methods: a descriptive correlational cross-sectional study was conducted. The universe of the study consisted of the population between 15 and 74 of the municipality of Cienfuegos in 2010, the sample was 644. The variables were considered: sex, skin colour, age, height, weight, index of body mass, abdominal waist, blood pressures: systolic, diastolic, average and differential (basal and sustained weight test and physical activity. Pearson Chi- square test was calculated and t was applied for comparison of average independent samples with a significance level of p = 0,05. Prevalence ratios were determined with a confidence interval of 95 %. Results: the prevalence of cardiovascular hyperactivity was higher in the group of 65-74 years and males. Cardiovascular hyperactives showed values of the average hemodynamic variables studied cardiovascular over normoreactive. There is an association between physical activity and better cardiovascular response in normal weight individuals. Conclusions: there is an association between increased blood pressure and obesity in cardiovascular hyperactivity. Physical activity is associated with cardiovascular normoreactivity in normal weight.

  2. The hemodynamic and hematologic effects of cigarette smoking versus a nicotine patch.

    Science.gov (United States)

    Netscher, D T; Wigoda, P; Thornby, J; Yip, B; Rappaport, N H

    1995-09-01

    Patients who smoke have higher complication rates than nonsmokers in the postoperative period. The authors designed an experimental protocol for habitual smokers (n = 30) to determine the specific hemodynamic and hematologic adverse effects possibly caused by nicotine and whether the method of nicotine delivery and systemic nicotine levels achieved might influence these adverse effects. During the 5-day study, subjects were asked to refrain from smoking, and testing sessions were conducted as follows: on day 1, the subjects smoked two cigarettes immediately before testing; on day 3 (control day), testing was done after not smoking for 48 hours and then the subjects were instructed to wear a transdermal nicotine patch (PROSTEP 22 mg/day) for 24 hours and replace it with another so that, on day 5, testing took place after the subjects had worn the patch for approximately 34 hours. At each testing session, digital artery pulse amplitude and a number of clinical and serum blood level parameters were measured. Relative digital blood flow after smoking (69.2 +/- 5.8%) and with the patch (80.4 +/- 7.6%) was lower than on the control day (100.0 +/- 0.0%). The nicotine patch, unlike smoking, had no effect on vasopressin or fibrinogen concentrations, hematocrit, or white cell or platelet counts; both smoking and the patch resulted in elevated norepinephrine levels.

  3. Emerging hemodynamic signatures of the right heart (Third International Right Heart Failure Summit, part 2).

    Science.gov (United States)

    Maron, Bradley A

    2014-12-01

    Despite the importance of preserved right ventricular structure and function with respect to outcome across the spectrum of lung, cardiac, and pulmonary vascular diseases, only recently have organized efforts developed to consider the pulmonary vascular-right ventricular apparatus as a specific unit within the larger context of cardiopulmonary pathophysiology. The Third International Right Heart Failure Summit (Boston, MA) was a multidisciplinary event dedicated to promoting a dialogue about the scientific and clinical basis of right heart disease. The current review provides a synopsis of key discussions presented during the section of the summit titled "Emerging Hemodynamic Signatures of the Right Heart." Specifically, topics emphasized in this element of the symposium included (1) the effects of pulmonary vascular dysfunction at rest or provoked by exercise on the right ventricular pressure-volume relationship, (2) the role of pressure-volume loop analysis as a method to characterize right ventricular inefficiency and predict right heart failure, and (3) the importance of a systems biology approach to identifying novel factors that contribute to pathophenotypes associated with pulmonary arterial hypertension and/or right ventricular dysfunction. Collectively, these concepts frame a forward-thinking paradigm shift in the approach to right heart disease by emphasizing factors that regulate the transition from adaptive to maladaptive right ventricular-pulmonary vascular (patho)physiology.

  4. Left ventricular geometric patterns and adaptations to hemodynamics are similar in elderly men and women

    Directory of Open Access Journals (Sweden)

    Sundström Johan

    2011-05-01

    Full Text Available Abstract Background Common conditions such as obesity and hypertension result in hemodynamic alterations that will induce remodeling of the left ventricle (LV. However, differences between the genders in the relationship of hemodynamics to LV geometry are not well known. The present study aims to investigate differences between the genders in this respect, in a sample of elderly persons. Methods Echocardiography and Doppler was performed in a population-based sample aged 70 - The Prospective Investigation of the Vasculature in Uppsala Seniors (PIVUS study (n = 922. Hemodynamic patterns obtained by echocardiography and Doppler were evaluated in relation to four LV geometric groups (normal, concentric remodeling, eccentric hypertrophy and concentric hypertrophy. Results No significant difference between the genders was observed regarding the prevalence of the LV geometric groups. Mean values of most evaluated echocardiography and Doppler variables differed between men and women, such as LA, IVS, LVEDD and IVRT, but the relationship of hemodynamic variables to LV geometric groups did not differ between the genders. Conclusions Although mean values of many echocardiographic variables differed between men and women, the LV geometric adaptations to a given hemodynamic load appear similar in both genders.

  5. Role of Hemodynamic Forces in Unruptured Intracranial Aneurysms: An Overview of a Complex Scenario.

    Science.gov (United States)

    Longo, Marcello; Granata, Francesca; Racchiusa, Sergio; Mormina, Enricomaria; Grasso, Giovanni; Longo, Giuseppe Maria; Garufi, Giada; Salpietro, Francesco M; Alafaci, Concetta

    2017-09-01

    An understanding of the natural history of unruptured intracranial aneurysms (IAs) has always played a critical role in presurgical or endovascular planning, to avoid possibly fatal events. Size, shape, morphology, and location are known risk factors for rupture of an aneurysm, but morphologic parameters alone may not be sufficient to perform proper rupture risk stratification. We performed a systematic PubMed search and focused on hemodynamics forces that may influence aneurysmal initiation, growth, and rupture. We included 223 studies describing several hemodynamic parameters related to aneurysm natural history. In these studies, different modalities of aneurysm model creation have been used to evaluate flow and to comprehensively analyze the evolution of IAs. Controversy exists about the correlation between these parameters and initiation, growth, rupture risk, or stabilization of the aneurysmal sac. Recent findings have also shown the importance of flow patterns in this process and the relationship between unruptured IA geometry and hemodynamic parameters. The role of hemodynamic forces in evaluation of the natural history of unruptured IAs presents is inherently complex and is still not completely understood. In this complex scenario, although several attempts have been described in the literature, a proper risk rupture stratification and treatment strategy selection based on hemodynamic forces has not yet been created. Further efforts should be made to accomplish this important goal. Copyright © 2017 Elsevier Inc. All rights reserved.

  6. Prediction of Hemodynamic Reactivity during Sevoflurane Remifentanyl Anesthesia for Laparoscopic Cholecystectomy Using Analgesia Nociception Index

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    Ali Şefik Köprülü

    2016-12-01

    Full Text Available Aim: Pneumoperitoneum may cause serious side effects in high-risk patients during laparoscopic cholecystectomy. Perioperative analgesic sufficiency has been measured by the Analgesia Nociception index (ANI in recent years. We examine the possibility of predicting hemodynamic reactivity by observing sudden changes in ANI during operation. Methods: In this retrospective study, recorded hemodynamic parameters (including heart rate, systolic/ diastolic blood pressure values and ANI values, before and after intubation, nasogastric tube application, intraperitoneal gas insufflation, and surgical incision in 31 patients who were applied laparoscopic cholecystectomy were compared by paired t-test. Additionally, an increment or decrement of 20% in ANI and 15% in hemodynamic parameters with respect to basal observation values were called “sudden changes”. Correlation of these parameters with sudden changes in ANI values was examined either. Results: There was a statistically significant difference in parameters after premedication and intubation. After induction, a statistically significant decrement was detected only in heart rate and systolic/diastolic blood pressure values. There was no significant change after nasogastric tube insertion. During pneumoperitoneum and surgical incision, there was no change in heart rate and systolic/diastolic blood pressure values, but a statistically significant decrement was observed in ANI. No correlation was detected between sudden changes in ANI values and hemodynamic parameters. Conclusion: We assume that use of ANI in analgesia evaluation under general anesthesia at perioperative period is suitable, however, it is not reliable in predicting hemodynamic interaction.

  7. Impact of Sitting or Semi-Setting Position of Patients During Breast Surgery on Hemodynamic Indexes

    Directory of Open Access Journals (Sweden)

    Kasra Karvandian

    2016-09-01

    Full Text Available Background: Keeping the patient in a sitting or semi-sitting position for time-consuming oncoplastic breast surgery is a major challenge for anesthesiologists due to several considerations. This cohort study was conducted on two groups of patients undergoing breast surgery.Methods: Study participants were categorized into two groups: one group was composed of normotensive women (group A and the other group comprised women with controlled hypertension (group B. After the induction of anesthesia in the supine position, the position was changed to sitting and the surgery was done in the sitting position. Hemodynamic monitoring included ECG, heart rate, non-invasive blood pressure (NIBP, invasive blood pressure (IBP, cardiac output (CO, arterial O2 saturation (SPO2, end-tidal CO2 (EtCO2, and bispectral index (BIS. The amount of administrated fluid and vasopressor was recorded for each patient. Any episode of hemodynamic instability was recorded, too.Results: Hemodynamic variation occurred in both groups, but the changes were more significant in group B and the amount of fluid and vasopressor administration was more prominent in group B. Changing the position caused no significant variation in BIS, SPO2, and EtCO2 in the two groups.Conclusions: The sitting position can be safe for time-consuming oncoplastic breast surgery using adequate hemodynamic monitoring. Hemodynamic changes are more significant in patients with controlled hypertension, and more medical interference is needed for these patients.

  8. Hemodynamics in stented vertebral artery ostial stenosis based on computational fluid dynamics simulations.

    Science.gov (United States)

    Qiao, Aike; Dai, Xuan; Niu, Jing; Jiao, Liqun

    2016-01-01

    Hemodynamic factors may affect the potential occurrence of in-stent restenosis (ISR) after intervention pro