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Sample records for stable hemodynamic status

  1. Ultrasound-Guided Drainage of Supralevator Hematoma in a Hemodynamically Stable Patient.

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    Mukhopadhyay, Debjani; Jennings, Paul E; Banerjee, Mamta; Gada, Ruta

    2015-12-01

    Paravaginal hematomas can be life-threatening. In patients with intact vaginal walls and perineum, they may pose a diagnostic and therapeutic challenge. Supralevator hematomas are much less common than infralevator hematomas. We present a case of puerperal hemorrhagic shock after a normal vaginal delivery in a low-risk parous woman resulting from an occult supralevator hematoma. Because the woman was hemodynamically unstable initially, she underwent a vaginal surgical drainage. A week later, the supravaginal hematoma reformed. At this time the patient was hemodynamically stable, and ultrasound-guided drainage was performed, which resulted in complete resolution of the hematoma within 10 days. In a clinically stable puerperal patient, ultrasound-guided drainage of a supralevator hematoma resulted in rapid and complete resolution of symptoms.

  2. Accuracy of chest radiography versus chest computed tomography in hemodynamically stable patients with blunt chest trauma

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    Chardoli Mojtaba

    2013-12-01

    Full Text Available 【Abstract】 Objective: Thoracic injuries are respon- sible for 25% of deaths of blunt traumas. Chest X-ray (CXR is the first diagnostic method in patients with blunt trauma. The aim of this study was to detect the accuracy of CXR versus chest computed tomograpgy (CT in hemodynami- cally stable patients with blunt chest trauma. Methods: Study was conducted at the emergency department of Sina Hospital from March 2011 to March 2012. Hemodynamically stable patients with at least 16 years of age who had blunt chest trauma were included. All patients underwent the same diagnostic protocol which consisted of physical examination, CXR and CT scan respectively. Results: Two hundreds patients (84% male and 16% female were included with a mean age of (37.9±13.7 years. Chin J Traumatol 2013;16(6:351-354 Rib fracture was the most common finding of CXR (12.5% and CT scan (25.5%. The sensitivity of CXR for hemothorax, thoracolumbar vertebra fractures and rib fractures were 20%, 49% and 49%, respectively. Pneumothorax, foreign body, emphysema, pulmonary contusion, liver hematoma and ster- num fracture were not diagnosed with CXR alone. Conclusion: Applying CT scan as the first-line diag- nostic modality in hemodynamically stable patients with blunt chest trauma can detect pathologies which may change management and outcome. Key words: Radiography; Thoracic injuries; Tomography, X-ray computed

  3. The Use of CT Scan in Hemodynamically Stable Children with Blunt Abdominal Trauma : Look before You Leap

    NARCIS (Netherlands)

    Nellensteijn, David R.; Greuter, Marcel J.; el Moumni, Moustafa; Hulscher, Jan B.

    We set out to determine the diagnostic value of computed tomographic (CT) scans in relation to the radiation dose, tumor incidence, and tumor mortality by radiation for hemodynamically stable pediatric patients with blunt abdominal injury. We focused on the changes in management because of new

  4. Central hemodynamics, vegetative status, and 40K excretion in children from regions with radioactive contamination

    International Nuclear Information System (INIS)

    Korovina, N.A.; Korenkov, I.P.; Zaplatnikov, A.A.

    1996-01-01

    Metabolism of potassium and natural radionuclide 40 K in children with functional disorders of circulatory organs, permanently living in areas with radiation contamination as a result of the Chernobyl accident is studied. Health status, cardiovascular function, vegetative homeostasis, and metabolism of stable potassium and 40 K were studied by clinical and instrumental methods in 61 children aged 10 t 14 years living in regions with radionuclide contamination in the Bryansk district (density of radiation contamination with 137 Cs 15 to 40 Ci/km 2 , level of 137 Cs incorporation up to 0.15 mkCi per organism. It was stated that six to seven years after the Chernobyl accident 58.3 to 62.5 % of children permanently living in regions with radionuclide contamination developed functional changes of the bioelectrical activity of the myocardium,, presenting as specific heart rhythm, conductivity, and repolarization process involving no disorders of the central hemodynamics; vegetative dysfunction was observed in 78.3 % children (p 40 K in different groups of children with functional disorders of the circulatory organs. 14 refs.; 3 tabs

  5. Outcome of Blunt Abdominal Traumas with Stable Hemodynamic and Positive FAST Findings

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    Firooz Behboodi

    2016-04-01

    Full Text Available Introduction: Focused assessment with sonography for trauma (FAST is a highly effective first screening tool for initial classification of abdominal trauma patients. The present study was designed to evaluate the outcome of patients with blunt abdominal trauma and positive FAST findings. Methods: The present prospective cross-sectional study was done on patients over 7 years old with normal abdominal examination, positive FAST findings, and available abdominopelvic computed tomography (CT scan findings. The frequency of need for laparotomy as well as its probable risk factors were calculated. Results: 180 patients were enrolled (mean age: 28.0 ± 11.5 years; 76.7% male. FAST findings were confirmed by abdominopelvic CT scan in only 124 (68.9% cases. Finally, 12 (6.6% patients needed laparotomy. Mean age of those in need of laparotomy was significantly higher than others (36.75 ± 11.37 versus 27.34 ± 11.37, p = 0.006. Higher grading of spleen (p = 0.001 and hepatic (p = 0.038 ruptures increased the probability of need for laparotomy. Conclusion: 68.9% of the positive FAST findings in patients with blunt abdominal trauma and stable hemodynamics was confirmed by abdominopelvic CT scan and only 6.6% needed laparotomy. Simultaneous presence of free fluid and air in the abdominal area, old age, and higher grading o solid organ injuries were factors that had a significant correlation with need for laparotomy.

  6. Outcome of Blunt Abdominal Traumas with Stable Hemodynamic and Positive FAST Findings.

    Science.gov (United States)

    Behboodi, Firooz; Mohtasham-Amiri, Zahra; Masjedi, Navid; Shojaie, Reza; Sadri, Peyman

    2016-01-01

    Focused assessment with sonography for trauma (FAST) is a highly effective first screening tool for initial classification of abdominal trauma patients. The present study was designed to evaluate the outcome of patients with blunt abdominal trauma and positive FAST findings. The present prospective cross-sectional study was done on patients over 7 years old with normal abdominal examination, positive FAST findings, and available abdominopelvic computed tomography (CT) scan findings. The frequency of need for laparotomy as well as its probable risk factors were calculated. 180 patients were enrolled (mean age: 28.0 ± 11.5 years; 76.7% male). FAST findings were confirmed by abdominopelvic CT scan in only 124 (68.9%) cases. Finally, 12 (6.6%) patients needed laparotomy. Mean age of those in need of laparotomy was significantly higher than others (36.75 ± 11.37 versus 27.34 ± 11.37, p = 0.006). Higher grading of spleen (p = 0.001) and hepatic (p = 0.038) ruptures increased the probability of need for laparotomy. 68.9% of the positive FAST findings in patients with blunt abdominal trauma and stable hemodynamics was confirmed by abdominopelvic CT scan and only 6.6% needed laparotomy. Simultaneous presence of free fluid and air in the abdominal area, old age, and higher grading o solid organ injuries were factors that had a significant correlation with need for laparotomy.

  7. Perfusion index variations in clinically and hemodynamically stable preterm newborns in the first week of life

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    Farinasso Daniela

    2010-01-01

    Full Text Available Abstract Background The perfusion index, derived from the pulse oximeter signal, seems to be an accurate predictor for high illness severity in newborns. The aim of this study was to determine the perfusion index values of clinically and hemodynamically stable preterm newborns in the first week of life. Methods Perfusion index recordings were performed on the first, third and seventh day of life on 30 preterm newborns. Their state of health was assessed according to clinical and behaviour evaluation and to the Score for Neonatal Acute Physiology. Results The median(interquartile range perfusion index values were 0.9(0.6 on the first, 1.2(1.0 on the third, and 1.3(0.9 on the seventh day, with a significant increase between the first and the third day. Conclusions Perfusion index proved to be an easily applicable, non-invasive method for monitoring early postnatal changes in peripheral perfusion. Its trend during the first week of life suggests that its clinical application should take age into account. Further studies are needed to obtain reference perfusion index values from a larger sample of preterm newborns, to identify specific gestational age-related cut-off values for illness and to test the role of perfusion index in monitoring critically ill neonates.

  8. Morphological and Hemodynamic Discriminators for Rupture Status in Posterior Communicating Artery Aneurysms.

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    Nan Lv

    Full Text Available The conflicting findings of previous morphological and hemodynamic studies on intracranial aneurysm rupture may be caused by the relatively small sample sizes and the variation in location of the patient-specific aneurysm models. We aimed to determine the discriminators for aneurysm rupture status by focusing on only posterior communicating artery (PCoA aneurysms.In 129 PCoA aneurysms (85 ruptured, 44 unruptured, clinical, morphological and hemodynamic characteristics were compared between the ruptured and unruptured cases. Multivariate logistic regression analysis was performed to determine the discriminators for rupture status of PCoA aneurysms.While univariate analyses showed that the size of aneurysm dome, aspect ratio (AR, size ratio (SR, dome-to-neck ratio (DN, inflow angle (IA, normalized wall shear stress (NWSS and percentage of low wall shear stress area (LSA were significantly associated with PCoA aneurysm rupture status. With multivariate analyses, significance was only retained for higher IA (OR = 1.539, p < 0.001 and LSA (OR = 1.393, p = 0.041.Hemodynamics and morphology were related to rupture status of intracranial aneurysms. Higher IA and LSA were identified as discriminators for rupture status of PCoA aneurysms.

  9. Should adrenaline be used in patients with hemodynamically stable anaphylaxis? Incident case control study nested within a retrospective cohort study.

    Science.gov (United States)

    Ko, Byuk Sung; Kim, Ji Yeon; Seo, Dong-Woo; Kim, Won Young; Lee, Jae Ho; Sheikh, Aziz; Bates, David W

    2016-02-03

    Although adrenaline (epinephrine) is a cornerstone of initial anaphylaxis treatment, it is not often used. We sought to assess whether use of adrenaline in hemodynamically stable patients with anaphylaxis could prevent the development of hypotension. We conducted a retrospective cohort study of 761 adult patients with anaphylaxis presenting to the emergency department (ED) of a tertiary care hospital over a 10-year period. We divided the patients into two groups according to the occurrence of hypotension and compared demographic characteristics, clinical features, treatments and outcomes. Of the 340 patients with anaphylaxis who were normotensive at first presentation, 40 patients experienced hypotension during their ED stay. The ED stay of the hypotension group was significantly longer than that of patients who did not experience hypotension (496 min vs 253 min, P = 0.000). Adrenaline use in hemodynamically stable anaphylaxis patient was independently associated with a lower risk of developing in-hospital occurrence of hypotension: OR, 0.254 [95% CI, 0.091-0.706]. Adrenaline use in hemodynamically stable anaphylaxis patients was associated with a reduced risk of developing in-hospital occurrence of hypotension. Adverse events induced by adrenaline were rare when the intramuscular route was used.

  10. Limitations of nonoperative management of type IIIb blunt hepatic injuries in hemodynamically stable patients after fluid resuscitation

    International Nuclear Information System (INIS)

    Sekine, Kazuhiko; Kitano, Mitsuhide; Shimizu, Masayuki; Matsumoto, Shokei; Yoshii, Hiroshi; Yamazaki, Motoyasu; Aikawa, Naoki

    2007-01-01

    Nonoperative management (NOM) of hepatic injuries caused by blunt trauma in hemodynamically stable patients is widely accepted, but the feasibility of NOM for severe hepatic injuries has not been fully evaluated. Among all patients with blunt severe hepatic injury (type IIIb) admitted to Saiseikai Kanagawa-ken Hospital and Keio University Hospital from 1988 to 2004, those who had been hemodynamically stable after fluid resuscitation at the emergency department were initially managed nonoperatively. We reviewed demographic, physiological, and laboratory data; computed tomography (CT) findings; 80-day cumulative laparotomy rate; and complications. The anatomical severity of the hepatic injuries was evaluated based on the CT findings, such as hepatic vein injuries and area lacerated according to the Couinaud liver segment. In patients who underwent surgery after admission, the surgical indications and operative findings were reviewed. Overall, 34 consecutive patients were enrolled in this study. Five patients underwent surgery, and all of their surgical indications were attributable to liver-related complications after injury. The indication for surgery was hemodynamic instability in 3 patients with hepatic vein injures in the early phase (<15 hours after estrogen receptor (ER) arrival) and intra-abdominal septic complications in 2 patients in the late phase (hospital days 14 and 64). The cumulative 80-day laparotomy rate in the early phase was significantly higher (p<0.0001) in the patients suspected of having hepatic vein injury, and in the late phase it was higher (p=0.002) in those with injuries in 4 or more segments of hepatic injuries. For the successful NOM of blunt hepatic injury type IIIb in patients who are hemodynamically stable after fluid resuscitation, a strong suspicion of concurrent hepatic vein injury is critical in the early phase, and laceration in 4 or more segments should be noted in the late phase. (author)

  11. Morphological and Hemodynamic Discriminators for Rupture Status in Posterior Communicating Artery Aneurysms

    OpenAIRE

    Lv, Nan; Wang, Chi; Karmonik, Christof; Fang, Yibin; Xu, Jinyu; Yu, Ying; Cao, Wei; Liu, Jianmin; Huang, Qinghai

    2016-01-01

    Background and Purpose The conflicting findings of previous morphological and hemodynamic studies on intracranial aneurysm rupture may be caused by the relatively small sample sizes and the variation in location of the patient-specific aneurysm models. We aimed to determine the discriminators for aneurysm rupture status by focusing on only posterior communicating artery (PCoA) aneurysms. Materials and Methods In 129 PCoA aneurysms (85 ruptured, 44 unruptured), clinical, morphological and hemo...

  12. A Pilot Review of Gradual Versus Goal Re-initiation of Enteral Nutrition after Burn Surgery in the Hemodynamically Stable Patient

    Science.gov (United States)

    2014-01-01

    nutrition after burn surgery in the hemodynamically stable patient 5a. CONTRACT NUMBER 5b. GRANT NUMBER 5c. PROGRAM ELEMENT NUMBER 6. AUTHOR(S) Shields...specific recommendations on the rate of delivery at initiation [6]. Once a patient is considered hemodynamically stable (HDS), common practice is to...differences in these practices were largely due to new residents and/or nursing staff. GRVs were monitored every 4 h. When GRVs were greater than 500 mL with EN

  13. HEMODYNAMIC STATUS IN AIRWAY MANAGEMENT DURING GENERAL ANESTHESIA: COMPARISON OF THREE METHODS

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    K MONTAZERI

    2000-03-01

    Full Text Available Introduction. The laryngeal mask airway (LMA was recently introduced in general anesthesia as an alternative to the face mask or tracheal intubation for airway maintenance. Methods. The effects of LMA insertion, face mask or tracheal intubation on homodynamic status were studied in 195 normotensive patients who underwent elective transurethral lithotripsy (TUL. The patients were monitored with blood pressure measurement and pulse oximetry. Anesthesia was induced with sodium thiopental, succynilcholine and fentanyl and maintained with halothane, nitrous oxide and oxygen. Findings. The heart rate (HR and mean arterial pressure increased after LMA insertion. face mask or tracheal intubation, compared with baseline (P<0.05. The hemodynamic changes were significantly greater after tracheal intubation and face mask than after LMA insertion (P<0.05. Conclusion. We conclude that insertion of LMA is associated with less hemodynamic disturbances than face mask or tracheal intubation in normotensive patients undergoing elective operations.

  14. Morphological and Hemodynamic Discriminators for Rupture Status in Posterior Communicating Artery Aneurysms.

    Science.gov (United States)

    Lv, Nan; Wang, Chi; Karmonik, Christof; Fang, Yibin; Xu, Jinyu; Yu, Ying; Cao, Wei; Liu, Jianmin; Huang, Qinghai

    2016-01-01

    The conflicting findings of previous morphological and hemodynamic studies on intracranial aneurysm rupture may be caused by the relatively small sample sizes and the variation in location of the patient-specific aneurysm models. We aimed to determine the discriminators for aneurysm rupture status by focusing on only posterior communicating artery (PCoA) aneurysms. In 129 PCoA aneurysms (85 ruptured, 44 unruptured), clinical, morphological and hemodynamic characteristics were compared between the ruptured and unruptured cases. Multivariate logistic regression analysis was performed to determine the discriminators for rupture status of PCoA aneurysms. While univariate analyses showed that the size of aneurysm dome, aspect ratio (AR), size ratio (SR), dome-to-neck ratio (DN), inflow angle (IA), normalized wall shear stress (NWSS) and percentage of low wall shear stress area (LSA) were significantly associated with PCoA aneurysm rupture status. With multivariate analyses, significance was only retained for higher IA (OR = 1.539, p PCoA aneurysms.

  15. 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

  16. Comparison of Brain Natriuretic Peptide Levels to Simultaneously Obtained Right Heart Hemodynamics in Stable Outpatients with Pulmonary Arterial Hypertension.

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    Helgeson, Scott A; Imam, J Saadi; Moss, John E; Hodge, David O; Burger, Charles D

    2018-05-01

    Pulmonary arterial hypertension (PAH) is a progressive disease that requires validated biomarkers of disease severity. While PAH is defined hemodynamically by right heart catheterization (RHC), brain natriuretic peptide (BNP) is recommended by guidelines to assess disease status. Retrospectively collected data in 138 group 1 PAH patients were examined for the correlation of BNP levels to simultaneously obtained right heart catheterization (RHC). Patients were mostly Caucasian women, with functional class III symptoms, mean BNP of 406 ± 443 pg/mL, and an average right atrial pressure (RAP) of 9.9 ± 5.7 mm Hg and mean pulmonary artery pressure (mPAP) of 47.3 ± 14.7 mm Hg. Significant correlation was demonstrated between BNP and RAP ( p = 0.021) and mPAP ( p = 0.003). Additional correlation was seen with right heart size on echocardiography: right atrial (RAE; p = 0.04) and right ventricular enlargement ( p = 0.03). An increased BNP level was an independent predictor of mortality ( p right heart hemodynamics. The current results reinforce the use of BNP level as a continuous variable to assess disease severity in group 1 PAH.

  17. Hemodynamics in the Sturge-Weber syndrome utilizing stable Xe-CT

    International Nuclear Information System (INIS)

    Okudaira, Yojiro; Bandoh, Kuniaki; Ito, Masanori; Sato, Kiyoshi; Tsuji, Masahiro

    1993-01-01

    In 4 Sturge-Weber-syndrome child patients with calcified lesions mainly in the occipital lobe, regional cerebral blood flow (rCBF) was determined with stable Xe-CT in the resting state and after iv injection of acetazolamide (AA) and megimide (M), with the purpose of examining factors affecting deterioration of neurologic manifestations and the influence of lobectomy. In the resting state, rCBF of the temporal and occipital areas was significantly lower on the affected than unaffected sides. The side-to-side asymmetry of rCBF in the affected and unaffected sides decreased from the frontal to temporal and occipital areas. It was indistinct after AA injection because cerebral vasoreactivity became higher on the affected side. A low rCBF in association with a high cerebral vasoreactivity on the lesion side suggested that the low rCBF matched the low cerebral metabolism of the brain area affected by leptomeningeal angiomatosis. However, cerebral vasoreactivity to AA depended on clinical presentations. Two patients presented with progressive mental retardation. The other two patients were in clinically stable condition. Cerebral vasoreactivity to AA in the former two cases was poorer on both the affected and unaffected sides than that in the latter two cases. M administration was associated with a significantly decreased rCBF in the area of leptomeningeal angiomatosis and cerebral calcification and with a significantly increased rCBF of the 'pericalcified' area. In one patient undergoing extended occipital lobectomy on the affected side, no decrease in rCBF was noted in the resting state in either affected or unaffected side, and cerebral vasoreactivity to AM on the unaffected side was apparently increased. Both circulatory disturbance and seizure appear to play a role in clinical presentations, as well as their deterioration in Sturge-Weber-Syndrome patients. (N.K.)

  18. The efficacy of ultrasonography in hemodynamically stable children with blunt abdominal trauma: a prospective comparison with computed tomography

    International Nuclear Information System (INIS)

    Tas, Fikret; Ceran, Canan; Atalar, Mehmet H.; Bulut, Sema; Selbes, Bilge; Isik, A. Oktay

    2004-01-01

    Purpose: In this prospective study we aimed to investigate the diagnostic value of ultrasonography (US) in hemodynamically stable children after blunt abdominal trauma (BAT) using computed tomography (CT) as the gold standard. Materials and methods: Between 1997 and 2001, 96 children with BAT were evaluated prospectively. CT was performed first, followed by US. US and CT examinations were independently evaluated by two radiologists for free fluid and organ injury. The sensitivity, specificity, positive predictive value, negative predictive value and overall accuracy of US were assessed regarding CT as the gold standard. Results: Overall 128 organ injuries were determined in 96 patients with CT; however, 20 (15.6%) of them could not be seen with US. Free intraabdominal fluid (FIF) was seen in 82 of 96 patients by CT (85.4%) and eight of them (9.7%) could not be seen by US. We found that sensitivity, specificity, positive predictive value, negative predictive value and overall accuracy of the US for free intra-abdominal fluid were 90.2, 100, 100, 63.6 and 91.7%, respectively. Conclusions: US for BAT in children is highly accurate and specific. It is highly sensitive in detecting liver, spleen and kidney injuries whereas its sensitivity is moderate for the detection of gastrointestinal tract (GIT) and pancreatic injuries

  19. Relationship between renal hemodynamic status and aging in patients without diabetes evaluated by renal Doppler ultrasonography.

    Science.gov (United States)

    Kawai, Tatsuo; Kamide, Kei; Onishi, Miyuki; Hongyo, Kazuhiro; Yamamoto-Hanasaki, Hiroko; Oguro, Ryosuke; Maekawa, Yoshihiro; Yamamoto, Koichi; Takeya, Yasushi; Sugimoto, Ken; Ohishi, Mitsuru; Rakugi, Hiromi

    2012-10-01

    Aging is well known as one of the major causes of a reduced glomerular filtration rate (GFR). The resistive index (RI) measured by renal Doppler ultrasonography (RDU) is thought to be a good indicator of renal vascular resistance induced by arteriosclerosis. In this study, we investigated whether RI could be used to evaluate the pathogenesis of renal damage or the mechanisms of reduction of renal function by aging. We investigated the correlation between RI and multiple clinical parameters and the influence of aging on the renal hemodynamic status of 194 in-patients (mean age 66.2 years) who underwent RDU at our hospital between February 2009 and July 2010. RI was significantly correlated with the age, estimated GFR (eGFR), diastolic blood pressure, pulse pressure, and degree of albuminuria. Subjects aged ≥75 years showed a significantly higher correlation coefficient between eGFR and RI. RI showed a stronger correlation with age in subjects aged ≥75 years compared to eGFR. The present study showed that renal vascular resistance and intra-renal arteriosclerosis had a greater impact on renal function in older than younger subjects, reflecting the possible mechanisms of renal function reduction due to aging.

  20. Central hemodynamics and left-ventricural contractility in patients with chronic obstructive pulmonary diseases and stable pulmonary hypertension: a radionuclide study

    International Nuclear Information System (INIS)

    Paleev, N.R.; Malov, G.A.; Cherejskaya, N.K.; Oblovatskaya, O.G.; Tsar'kova, L.N.; Zil'berman, E.Eh.; Akademiya Meditsinskikh Nauk SSSR, Moscow. Inst. Serdechno-Sosudistoj Khirurgii)

    1987-01-01

    Systemic, central and intracardiac hemodynamics and left-ventricular contractility were studied radiocardiographically and radioventriculographically in 22 patients with stable pulmanory hypertension, developing in the presence of chronic obstructive pulmanory diseases. A tendency to increased circulating blood volume, significantly elevated end diastolic and end systolic indices, reduced total ejection fraction, and a tendency to decreased segmental ejection fractions were demonstrated. A significant reduction of the speed and percetage of left-ventricular myocardial circular fibre contraction is another evedence of incompetent left-ventricular contractility, in addition to the reduced ejection fraction

  1. Availability of enriched stable isotopes: present status and future prospects

    International Nuclear Information System (INIS)

    Hoff, R.W.

    1986-01-01

    The Electromagnetic Isotope Enrichment Facility (EMIEF) is currently used to produce 225 enriched stable isotopes of 50 elements. Among these are included most of the known elements with stable isotopes except for the noble gases, certain light elements, monisotopic elements, etc. The EMIEF can also be used to produce enriched samples of radioactive species, most notably the isotopes of uranium and plutonium. These enriched materials are placed in either the Sales Inventory of in the Research Materials Collection (RMC). The materials in the Sales Inventory are for sale to anyone on a first come, first served basis. Prices in the most recent catalog range from $0.05/mg for 99.8% 140 Ce to $1,267/mg for 98.5% 176 Lu. The materials in the RMC are made available to US researchers (or groups that include a US investigator) on a loan basis for use in non-destructive experiments and applications. In addition, certain samples have been provided to European investigators for cross-section studies through the auspices of EURATOM and the European-American Nuclear Data Committee. The status of the enriched isotopes included in the Sales Inventory is tabulated where isotopes are listed that are either not available or are in insufficient quantity or quality to meet current requests, as of 6/30/86. These can be summarized in the following subcategories: isotopes with zero inventory (22), Isotopes of insufficient quantity (17), and isotopes with insufficient enrichment quality (10). Of these 49 species, the supplies of 10 will be replenished by the scheduled FY86 enrichments in process (isotopes of bromine, calcium, nickel, potassium, rubidium, and strontium). In Table 3 are listed isotopes where the current inventory is less than the average annual sales level for the past five years. There are 47 isotopes listed, representing 25 different elements. Thus, there exists considerable potential for a substantial increase in the number of isotopes with zero inventory

  2. The status of applying stable isotope in the studies of environmental science

    International Nuclear Information System (INIS)

    Bai Zhipeng; Zhang Liwen; Zhu Tan; Feng Yinchang

    2007-01-01

    The stable isotope composition is characteristic in the pollution source, and it is relatively fixed in the process of transferring and reaction. At present the precise analysis result of stable isotope ratio can be obtained easily. So the stable isotopes can be applied to the pollution affair arbitration and source study. The concept and analytical method of stable isotopes are introduced. The research status of the stable isotopes in the field of environmental science and the isotope fractionation is reviewed. (authors)

  3. Growth Status of Iranian Children with Hemodynamically Important Congenital Heart Disease

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    Mohammad Dalili

    2011-02-01

    Full Text Available The relationship between congenital heart disease (CHD and growth retardation is well documented. We investigated the growth condition of Iranian children with several types of congenital heart disease (CHD and compared it with worldwide researches. Growth condition was investigated in 469 patients with important CHD aged from 1 month to 18 years. The patients were divided into two groups; infants (aged 12 months or less, and children (1-18 yrs of age. Children with hemodynamically unimportant small VSDs or small ASDs were not studied. Other exclusion criteria were prematurity, known genetic disorders and neurologic disease affecting growthd. All patients' cardiac diagnoses were made on the basis of clinical and laboratory examinations; including electrocardiography, echocardiography, cardiac catheterization, and angiography. Body weight and height of all patients were measured using conventional methods and compared with standard growth charts. In all patients body weights and heights were significantly lower than normal population. This difference was greater in the weight of female children. Other risk factors for growth failure were large left-to-right intracardiac shunts, pulmonary hypertension and cyanosis. Iranian children with CHD have growth failure somewhat different from other countries. Lower body weights of cyanotic patients and female children indicated that these patients need more nutritional and psychosocial attention.

  4. Acid–base and hemodynamic status of patients with intraoperative hemorrhage using two solution types: Crystalloid Ringer lactate and 1.3% sodium bicarbonate in half-normal saline solution

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    Sayed Jalal Hashemi

    2016-01-01

    Conclusion: 1.3% sodium bicarbonate in half-normal saline solution can lead to a proper correction of hemodynamic instability. By maintaining hemodynamic status, osmolarity and electrolytes as well as better balance of acid–base, 1.3% sodium bicarbonate solution in half-normal saline solution can be more effective than Ringer lactate solution during intraoperative bleeding.

  5. HEMODYNAMIC STATUS IN AIRWAY MANAGEMENT DURING GENERAL ANESTHESIA: COMPARISON OF THREE METHODS

    OpenAIRE

    K MONTAZERI; KH NAGHIBI; A.A AKHOUNDI

    2000-01-01

    Introduction. The laryngeal mask airway (LMA) was recently introduced in general anesthesia as an alternative to the face mask or tracheal intubation for airway maintenance. Methods. The effects of LMA insertion, face mask or tracheal intubation on homodynamic status were studied in 195 normotensive patients who underwent elective transurethral lithotripsy (TUL). The patients were monitored with blood pressure measurement and pulse oximetry. Anesthesia was induced with sodium thiopental,...

  6. COMPARISON OF EFFECTIVENESS OF A PROGRESSIVE MOBILIZATION AND MOZART MUSIC THERAPY ON NON-INVASIVE HEMODYNAMIC STATUS CHANGES IN PATIENTS WITH HEAD INJURY IN THE INTENSIVE CARE UNIT

    Directory of Open Access Journals (Sweden)

    Novi Indriani

    2018-05-01

    Full Text Available Background: The instability of hemodynamic status in patients with head injury with decreased consciousness has an effect on the increase of intracranial pressure. The recovery of hemodynamic status can be done through nursing intervention either by providing a sensory stimulus (music therapy or motor stimulus (progressive mobilization. Objective: To compare the effectiveness of progressive mobilization of level I with Mozart's music therapy on non-invasive hemodynamic status changes in patients with head injury with decreased awareness. Methods: This was a quasy-experimental study with pretest-posttest design. There were 34 samples selected using consecutive sampling, which 17 samples assigned in a group of progressive mobilization and group of music therapy. Paired t-test and Wilcoxon test were used for paired group, and Independent t-test and Mann-Whitney test for unpaired group. Results: Progressive mobilization of level I had significant effect on changes in systolic blood pressure (p = 0.0001, diastolic blood pressure (p = 0.002 and MAP (p = 0.019, and no significant effect on heart rate (p = 0.155, respiration (p = 0.895 and oxygen saturation (p = 0.248. Mozart's music therapy had a significant effect on changes in systolic blood pressure (p = 0.0001, diastolic blood pressure (p = 0.0001, respiration (p= 0.032 and oxygen saturation (p = 0.008, but no effect on MAP (p = 0.561. There was a significant difference between the two interventions in the systolic blood pressure and heart rate variables (p 0.05. Conclusion: The Mozart's music therapy is more effective on non-invasive hemodynamic status changes in patients with head injury with decreased consciousness compared with progressive mobilization of level I.

  7. Hemodynamic evaluation in patients with superficial temporal artery-middle cerebral artery anastomosis; Stable xenon CT-CBF study and acetazolamide

    Energy Technology Data Exchange (ETDEWEB)

    Touho, Hajime; Karasawa, Jun; Shishido, Hisashi; Morisako, Toshitaka; Yamada, Keisuke; Shibamoto, Keiji [Osaka Neurological Inst., Toyonaka (Japan)

    1990-12-01

    Sixteen patients with minor completed stroke in the chronic stage underwent superficial temporal artery-middle cerebral artery (STA-MCA) anastomosis. The acetazolamide-activated regional cerebral blood flow (rCBF) was measured 20 minutes after the injection using inhalation of stable xenon and computed tomographic scanning (Xe{sup s} CT-CBF study) pre- and postoperatively. Eleven patients (Group 1) showed immediate improvement in neurological state within a few days of the operation, while five (Group 2) showed no improvements. Preoperative rCBF in the ischemic areas without infarction was 30.8+-3.0 ml/100 gm/min in Group 1 and 53.0+-5.2 ml/100 gm/min in Group 2. Preoperative vasodilatory capacity with acetazolamide in Group 1 was 5.7+-8.6 and significantly increased to 19.8+-4.9 after surgery. In Group 2, pre- and postoperative vasodilatory capacity was 12.7+-3.1 and 14.9+-2.9, respectively, and there was no significant change. These results suggested that minor stroke patients with moderate decrease of affected side rCBF (less than 40 ml/100 gm/min) and with hemodynamic impairment may have the surgical indication for STA-MCA anastomosis. (author).

  8. England and Wales: Stable fertility and pronounced social status differences

    Directory of Open Access Journals (Sweden)

    Wendy Sigle-Rushton

    2008-07-01

    Full Text Available For nearly three decades, the total fertility rate in England and Wales has remained high relative to other European countries, and stable at about 1.7 births per woman. In this chapter, we examine trends in both period and cohort fertility throughout the twentieth century, and demonstrate some important differences across demographic and social groups in the timing and quantum of fertility. Breaking with a market-oriented and laissez-faire approach to work and family issues, the last 10 years have seen the introduction of new social and economic policies aimed at providing greater support to families with children. However, the effect of the changes is likely to be limited to families on the lower end of the income scale. Rather than facilitating work and parenthood, some policies create incentives for a traditional gendered division of labour. Fertility appears to have remained stable despite, rather than because of, government actions.

  9. Focal hemodynamic patterns of status epilepticus detected by susceptibility weighted imaging (SWI)

    Energy Technology Data Exchange (ETDEWEB)

    Aellen, Jerome; Kottke, Raimund; Springer, Elisabeth; Weisstanner, Christian; El-Koussy, Marwan; Schroth, Gerhard; Wiest, Roland; Gralla, Jan; Verma, Rajeev K. [University of Bern, University Institute for Diagnostic and Interventional Neuroradiology, University Hospital Bern and Inselspital, Bern (Switzerland); Abela, Eugenio; Schindler, Kaspar [University of Bern, Department of Neurology, Inselspital, Bern (Switzerland); Buerki, Sarah E. [Inselspital, Department of Neuropaediatrics, University Children' s Hospital, Bern (Switzerland)

    2014-11-15

    To investigate pathological findings in the susceptibility weighted imaging (SWI) of patients experiencing convulsive (CSE) or non-convulsive status epilepticus (NCSE) with focal hyperperfusion in the acute setting. Twelve patients (six with NCSE confirmed by electroencephalogram (EEG) and six patients with CSE with seizure event clinically diagnosed) underwent MRI in this acute setting (mean time between onset of symptoms and MRI was 3 h 8 min), including SWI, dynamic susceptibility contrast MR imaging (DSC) and diffusion-weighted imaging (DWI). MRI sequences were retrospectively evaluated and compared with EEG findings (10/12 patients), and clinical symptoms. Twelve out of 12 (100 %) patients showed a focal parenchymal area with pseudo-narrowed cortical veins on SWI, associated with focal hyperperfused areas (increased cerebral blood flow (CBF) and mean transit time (MTT) shortening), and cortical DWI restriction in 6/12 patients (50 %). Additionally, these areas were associated with ictal or postical EEG patterns in 8/10 patients (80 %). Most frequent acute clinical findings were aphasia and/or hemiparesis in eight patients, and all of them showed pseudo-narrowed veins in those parenchymal areas responsible for these symptoms. In this study series with CSE and NCSE patients, SWI showed focally pseudo-narrowed cortical veins in hyperperfused and ictal parenchymal areas. Therefore, SWI might have the potential to identify an ictal region in CSE/NCSE. (orig.)

  10. Focal hemodynamic patterns of status epilepticus detected by susceptibility weighted imaging (SWI)

    International Nuclear Information System (INIS)

    Aellen, Jerome; Kottke, Raimund; Springer, Elisabeth; Weisstanner, Christian; El-Koussy, Marwan; Schroth, Gerhard; Wiest, Roland; Gralla, Jan; Verma, Rajeev K.; Abela, Eugenio; Schindler, Kaspar; Buerki, Sarah E.

    2014-01-01

    To investigate pathological findings in the susceptibility weighted imaging (SWI) of patients experiencing convulsive (CSE) or non-convulsive status epilepticus (NCSE) with focal hyperperfusion in the acute setting. Twelve patients (six with NCSE confirmed by electroencephalogram (EEG) and six patients with CSE with seizure event clinically diagnosed) underwent MRI in this acute setting (mean time between onset of symptoms and MRI was 3 h 8 min), including SWI, dynamic susceptibility contrast MR imaging (DSC) and diffusion-weighted imaging (DWI). MRI sequences were retrospectively evaluated and compared with EEG findings (10/12 patients), and clinical symptoms. Twelve out of 12 (100 %) patients showed a focal parenchymal area with pseudo-narrowed cortical veins on SWI, associated with focal hyperperfused areas (increased cerebral blood flow (CBF) and mean transit time (MTT) shortening), and cortical DWI restriction in 6/12 patients (50 %). Additionally, these areas were associated with ictal or postical EEG patterns in 8/10 patients (80 %). Most frequent acute clinical findings were aphasia and/or hemiparesis in eight patients, and all of them showed pseudo-narrowed veins in those parenchymal areas responsible for these symptoms. In this study series with CSE and NCSE patients, SWI showed focally pseudo-narrowed cortical veins in hyperperfused and ictal parenchymal areas. Therefore, SWI might have the potential to identify an ictal region in CSE/NCSE. (orig.)

  11. The contributions of adrenal hormones, hemodynamic factors, and the endotoxin-related stress reaction to stable prostaglandin analog-induced peripheral lymphopenia and neutrophilia.

    Science.gov (United States)

    Ulich, T R; Keys, M; Ni, R X; del Castillo, J; Dakay, E B

    1988-01-01

    Stable prostaglandin analogs are known to induce lymphopenia and neutrophilia in a dose-dependent fashion after subcutaneous injection in rats. The purpose of the present investigation is to determine whether the prostaglandin-induced changes in circulating leukocytes might be secondary to hypotension with the ensuing release of adrenal hormones. The adrenal medullary catecholamine epinephrine was found to induce neutrophilia in both intact and adrenalectomized rats, and the glucocorticosteroid analog dexamethasone induced a profound lymphopenia in rats as reported by previous investigators. A stable analog of PGF2 alpha (15-S-15-methyl PGF2 alpha; M-PGF2 alpha) at the dose of 1 mg/kg induced marked systemic hypotension 1 h after injection, with lymphopenia and neutrophilia 6 h after injection. The non-prostanoid hypotensive agent captopril, at a dose of 63 mg/kg, induced a hypotension of similar magnitude and kinetics to that induced by prostaglandin. Captopril also induced lymphopenia and neutrophilia at 6 h, although the neutrophilia was of lesser magnitude than that induced by prostaglandins. The prostaglandin-induced lymphopenia was found to be mediated, at least in part, by the hypotension-induced release of adrenal hormones, as evidenced by the abrogation of lymphopenia in prostaglandin-treated adrenalectomized rats. Captopril-treated adrenalectomized rats, however, did develop a significant lymphopenia, suggesting that hypotension can result in lymphopenia even in adrenalectomized rats. The M-PGF2 alpha-induced neutrophilia in adrenalectomized rats, by comparison to captopril-induced neutrophilia in adrenalectomized rats, was greater than the neutrophilia expected as the result of hypotension alone. Indeed, the M-PGF2 alpha-induced neutrophilia in adrenalectomized rats was greater than the captopril-induced neutrophilia in sham-adrenalectomized rats. Thus, a portion of the neutrophilia induced by M-PGF2 alpha in intact rats may be mediated through adrenal

  12. Hemodynamic imaging of cerebrovascular disease

    Energy Technology Data Exchange (ETDEWEB)

    Grond, J. van der; Hendrikse, J.; Osch, M.J.P. van [Dept. of Radiology, University Hospital Utrecht (Netherlands)

    2001-11-01

    MR can provide data on perfusion, oxygen consumption and oxygen metabolism, which can be of great value in stroke research. This article reviews the possibilities and current status of the MR techniques with respect to intracranial hemodynamic changes. (orig.)

  13. MUSIC AND AROMATHERAPY: A GOOD COMBINATION FOR REDUCING ANXIETY AND STABILIZING NON-INVASIVE HEMODYNAMIC STATUS IN PATIENTS IN THE INTENSIVE CARE UNIT

    Directory of Open Access Journals (Sweden)

    Ferry Kumala

    2018-05-01

    Full Text Available Background: Combining musical and aromatherapy therapy is expected to have a stronger effect in the reduction of anxiety and non-invasive hemodynamic stability. Objective: To examine the effect of the combination of music and aromatherapy on anxiety and non-invasive hemodynamic in patients in the intensive care unit. Methods: This was a quasy experimental study with non-equivalent group. An experimental group was given a combined musical and aromatherapy, while a control group was given music therapy. Thirty samples selected using accidental sampling, with 15 samples randomly assigned in the music group and combination group. HARS scale (Hamilton Anxiety Rating Scale was used to measure anxiety. Non-invasive hemodynamic status of patients such as blood pressure and heart rate were documented in the observation sheet. Paired t-test and one-way ANOVA were used for data analysis. Results: There were significant effects of combination therapy on anxiety (p=0.001, diastole (p=0.004 and heart rate (p=0.031, but no significant effect on systole (p=0.387. While music therapy alone had a significant effect on anxiety (p=0.001, systole (p=0.047, and diastole (p=0.037. Conclusion: The combination therapy (music-aromatherapy had a greater effect than the music therapy alone in decreasing anxiety, and stabilizing diastolic blood pressure and heart rate. This therapy can be used as an alternative in nursing interventions, and can be used as inputs to develop standard of operational procedure for anxiety and non-invasive hemodynamic stability.

  14. Stable fetal hemodynamics measured by Doppler flow after initiation of anti-hypertensive treatment with methyldopa in pregnant women with diabetes

    DEFF Research Database (Denmark)

    Pedersen, Berit Woetmann; Ringholm, Lene; Damm, Peter

    2016-01-01

    AIM: To evaluate whether initiation of anti-hypertensive treatment with methyldopa affects fetal hemodynamics in women with pregestational diabetes. METHODS: Prospective study of unselected singleton pregnant women with diabetes (seven type 1 and two type 2 diabetes), normal blood pressure and ki...

  15. Stable isotope usage in developing countries: Safe tracer tools to measure human nutritional status

    International Nuclear Information System (INIS)

    Klein, P.D.; Klein, E.R.

    1987-01-01

    How many calories are used when a nursing mother feeds her infant? How much milk does an infant receive in one week? What is the impact of the environment on the energy needs of children? How adequately does dietary protein sustain the synthesis of body constituents? What types of foods best nourish a child recovering from intestinal diseases such as diarrhoea? Quantitative answers to questions such as these can be obtained from the use of stable, non-radioactive isotopic tracers. Answers to these questions are important in assessing the nutritional status of infants, children, pregnant women and nursing mothers, as well as that of individuals who subsist on marginal food supplies. Because stable isotopic tracers are completely safe and without hazard, they can be used freely in health, nutrition, and agriculture studies in all populations

  16. Hemodynamics in the Sturge-Weber syndrome utilizing stable Xe-CT; With special reference to the perfusion reserve and the epileptic focus activated by megimide

    Energy Technology Data Exchange (ETDEWEB)

    Okudaira, Yojiro; Bandoh, Kuniaki; Ito, Masanori; Sato, Kiyoshi; Tsuji, Masahiro (Juntendo Univ., Tokyo (Japan). School of Medicine)

    1993-02-01

    In 4 Sturge-Weber-syndrome child patients with calcified lesions mainly in the occipital lobe, regional cerebral blood flow (rCBF) was determined with stable Xe-CT in the resting state and after iv injection of acetazolamide (AA) and megimide (M), with the purpose of examining factors affecting deterioration of neurologic manifestations and the influence of lobectomy. In the resting state, rCBF of the temporal and occipital areas was significantly lower on the affected than unaffected sides. The side-to-side asymmetry of rCBF in the affected and unaffected sides decreased from the frontal to temporal and occipital areas. It was indistinct after AA injection because cerebral vasoreactivity became higher on the affected side. A low rCBF in association with a high cerebral vasoreactivity on the lesion side suggested that the low rCBF matched the low cerebral metabolism of the brain area affected by leptomeningeal angiomatosis. However, cerebral vasoreactivity to AA depended on clinical presentations. Two patients presented with progressive mental retardation. The other two patients were in clinically stable condition. Cerebral vasoreactivity to AA in the former two cases was poorer on both the affected and unaffected sides than that in the latter two cases. M administration was associated with a significantly decreased rCBF in the area of leptomeningeal angiomatosis and cerebral calcification and with a significantly increased rCBF of the 'pericalcified' area. In one patient undergoing extended occipital lobectomy on the affected side, no decrease in rCBF was noted in the resting state in either affected or unaffected side, and cerebral vasoreactivity to AM on the unaffected side was apparently increased. Both circulatory disturbance and seizure appear to play a role in clinical presentations, as well as their deterioration in Sturge-Weber-Syndrome patients. (N.K.).

  17. The evaluation of cerebral hemodynamics in patients with intracranial tumors by stable xenon CT; The effect of glycerol administration on regional cerebral blood flow

    Energy Technology Data Exchange (ETDEWEB)

    Shimoda, Masami; Kawamata, Fumio; Yamamoto, Masahiro; Ohsuga, Hitoshi; Hidaka, Mitsuru; Oda, Shinri; Shibuya, Naoki; Yamamoto, Isao; Sato, Osamu (Tokai Univ., Isehara, Kanagawa (Japan). School of Medicine)

    1989-04-01

    In evaluating cerebral regional blood flow (rCBF), stable xenon-enhanced tomography (XeCT) study associated with simultaneous blood sampling was applied in 15 cases of intracranial neoplasms. The effect of intravenous glycerol infusion on rCBF was also investigated. The results indicated that intratumoral rCBF values were not only variable and unrelated to their histological types and grades, but also were not correlated with the vascularity of the lesion as demonstrated by angiography. When a tumor mass was enhanced after the injection of iodinated contrast media, it proved to be useful in distinguishing tumor mass and its associated edema that the rCBF of the peritumoral edematous region was predominantly low (10{plus minus}5 ml/100 g/min). The regional cerebral blood flow in remote areas, both ipsilateral and contralateral to the lesion, was low in value, and there was no statistical significance between affected and sound sides. Following glycerol administration, rCBF was increased in the whole intracranial region, but not inside of the neoplasm, particularly when the intracranial pressure (ICP) was increased. It was assumed that the elevated rCBF after glycerol administration was due to the increase in the cerebral perfusion pressure resulting from the ICP reduction, the hemodilution effect, cerebral vessel dilatation after metabolic acidosis, and/or mechanically rectified microcirculation after edema reduction. (author).

  18. Preditores de mortalidade hospitalar em pacientes com embolia pulmonar estáveis hemodinamicamente Predictores de mortalidad hospitalaria en pacientes con embolia pulmonar estables hemodinámicamente Predictors of hospital mortality in hemodynamically stable patients with pulmonary embolism

    Directory of Open Access Journals (Sweden)

    André Volschan

    2009-08-01

    or circulatory shock. However, the association between some clinical variables and mortality is still unclear in hemodynamically stable patients. OBJECTIVES: To derive an in-hospital mortality risk stratification model in hemodynamically stable patients with pulmonary embolism. METHODS: This is a prospective multicenter cohort study of 582 consecutive patients admitted in emergency units or intensive care units with clinically suspected pulmonary embolism and whose diagnosis was confirmed by one or more of the following tests: pulmonary arteriography, spiral CT angiography, magnetic resonance angiography, Doppler echocardiography, pulmonary scintigraphy, or venous duplex scan. Data on demographics, comorbidities and clinical manifestations were collected and included in a logistic regression analysis so as to build the prediction model. RESULTS: Overall mortality was 14.1%. The following parameters were identified as independent death risk variables: age > 65 years, bed rest > 72h, chronic cor pulmonale, sinus tachycardia, and tachypnea. After risk stratification, mortalities of 5.4%, 17.8%, and 31.3% were found in the low, moderate and high-risk subgroups, respectively. The model showed 65.5% sensitivity and 80% specificity, with a 0.77 area under the curve. CONCLUSION: In hemodynamically stable patients with pulmonary embolism, age > 65 years, bed rest > 72h, chronic cor pulmonale, sinus tachycardia and tachypnea were independent predictors of in-hospital mortality. However, further validation of the prediction model in other populations is required so that it can be incorporated into the clinical practice.

  19. Laparoscopic Splenectomy in Hemodynamically Stable Blunt Trauma.

    Science.gov (United States)

    Huang, Gregory S; Chance, Elisha A; Hileman, Barbara M; Emerick, Eric S; Gianetti, Emily A

    2017-01-01

    No criteria define indications for laparoscopic splenectomy in trauma. This investigation compared characteristics of trauma patients and outcomes between laparoscopic and open splenectomies. Patients were identified retrospectively by using ICD-9 codes. Included patients were 18 or older, with a blunt splenic injury from January 1, 2011, through December 31, 2014, and required splenectomy. Excluded patients had penetrating trauma, successful nonoperative management, or successful embolization. Variables included demographics, presenting characteristics, injury severity scores, abdominal abbreviated injury scores, splenic injury grade, surgical indication and approach (open or laparoscopic), surgery length, intra-operative blood loss, transfusions, length of stay, complications, mortality, and discharge disposition. Forty-one patients underwent open splenectomy, and 11 underwent laparoscopic splenectomy. The mean age was 48.7 years, and men comprised the sample majority (36/52). The groups were well matched for age, abdominal injury scores, and admission vital signs. The open group had a significantly lower level of consciousness and more acidosis compared with the laparoscopic group. Most laparoscopic splenectomies were performed after failed nonoperative management or embolization. The indications for open splenectomy were a positive focused assessment with sonography for trauma and computed tomography results. Laparoscopic patients had significantly longer times between presentation and surgery and longer operations, but had significantly less blood loss and fewer transfusions compared with the open group. There were no differences in mortality, length of stay, complications, or discharge dispositions. Laparoscopic splenectomy is useful in patients with blunt trauma in whom conservative management produced no improvement and who do not have other injuries to preclude laparoscopy.

  20. 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

  1. Acid-base and hemodynamic status of patients with intraoperative hemorrhage using two solution types: Crystalloid Ringer lactate and 1.3% sodium bicarbonate in half-normal saline solution.

    Science.gov (United States)

    Hashemi, Sayed Jalal; Heidari, Sayed Morteza; Yaraghi, Ahmad; Seirafi, Reza

    2016-01-01

    Intraoperative hemorrhage is one of the problems during surgery and, if it happens in a high volume without an immediate action to control, it can be fatal. Nowadays, various injectable solutions are used. The aim of this study was to compare the acid-base and hemodynamic status of the patient using two solutions, Ringer lactate and 1.3% sodium bicarbonate, in half saline solution. This clinical trial was performed at the Al-Zahra Hospital in 2013 on 66 patients who were randomly selected and put in two studied groups at the onset of hemorrhage. For the first group, crystalloid Ringer lactate solution and for the second group, 1.3% sodium bicarbonate in half-normal saline solution was used. Electrocardiogram, heart rate, O2 saturation non-invasive blood pressure and end-tidal CO2 were monitored. The arterial blood gas, blood electrolytes, glucose and blood urea nitrogen were measured before serum and blood injection. After the infusion of solutions and before blood transfusions, another sample was sent for measurement of blood parameters. Data were analyzed using SPSS software. The mean arterial pressure was significantly higher in the second group than in the first group at some times after the infusion of solutions. pHh levels, base excess, bicarbonate, sodium, strong ion differences and osmolarity were significantly greater and potassium and chloride were significantly lower in the second group than in the first group after the infusion of solutions. 1.3% sodium bicarbonate in half-normal saline solution can lead to a proper correction of hemodynamic instability. By maintaining hemodynamic status, osmolarity and electrolytes as well as better balance of acid-base, 1.3% sodium bicarbonate solution in half-normal saline solution can be more effective than Ringer lactate solution during intraoperative bleeding.

  2. Stable isotope evidence for sex- and status-based variations in diet and life history at medieval Trino Vercellese, Italy.

    Science.gov (United States)

    Reitsema, Laurie J; Vercellotti, Giuseppe

    2012-08-01

    The medieval period in Europe was a time of unprecedented social complexity that affected human diet. The diets of certain subgroups-for example, children, women, and the poor-are chronically underrepresented in historical sources from the medieval period. To better understand diet and the distribution of foods during the medieval period, we investigated stable carbon and nitrogen isotope ratios of 30 individuals from Trino Vercellese, Northern Italy (8th-13th c.). Specifically, we examined diet differences between subgroups (males and females, and high- and low-status individuals), and diet change throughout the life course among these groups by comparing dentine and bone collagen. Our results show a diet based on terrestrial resources with input from C(4) plants, which could include proso and/or foxtail millet. Diets of low-status males differ from those of females (both status groups) and of high-status males. These differences develop in adulthood. Childhood diets are similar among the subgroups, but sex- and status-based differences appear in adulthood. We discuss the possibility of cultural buffering and dietary selectivity of females and high-status individuals. Copyright © 2012 Wiley Periodicals, Inc.

  3. Status of stable isotope enrichment, products, and services at the Oak Ridge National Laboratory

    International Nuclear Information System (INIS)

    Aaron, W.S.; Tracy, J.G.; Collins, E.D.

    1997-01-01

    The Oak Ridge national laboratory (ORNL) has been supplying enriched stable and radioactive isotopes to the research, medical, and industrial communities for over 50 y. Very significant changes have occurred in this effort over the past several years, and, while many of these changes have had a negative impact on the availability of enriched isotopes, more recent developments are actually improving the situation for both the users and the producers of enriched isotopes. ORNL is still a major producer and distributor of radioisotopes, but future isotope enrichment operations to be conducted at the isotope enrichment facility (IEF)fwill be limited to stable isotopes. Among the positive changes in the enriched stable isotope area are a well-functioning, long-term contract program, which offers stability and pricing advantages; the resumption of calutron operations; the adoption of prorated conversion charges, which greatly improves the pricing of isotopes to small users; ISO 9002 registration of the IEF's quality management system; and a much more customer-oriented business philosophy. Efforts are also being made to restore and improve upon the extensive chemical and physical form processing capablities that once existed in the enriched stable isotope program. Innovative ideas are being pursued in both technical and administrative areas to encourage the beneficial use of enriched stable isotopes and the development of related technologies. (orig.)

  4. Status of stable isotope enrichment, products, and services at the Oak Ridge National Laboratory

    Science.gov (United States)

    Scott Aaron, W.; Tracy, Joe G.; Collins, Emory D.

    1997-02-01

    The Oak Ridge National Laboratory (ORNL) has been supplying enriched stable and radioactive isotopes to the research, medical, and industrial communities for over 50 y. Very significant changes have occurred in this effort over the past several years, and, while many of these changes have had a negative impact on the availability of enriched isotopes, more recent developments are actually improving the situation for both the users and the producers of enriched isotopes. ORNL is still a major producer and distributor of radioisotopes, but future isotope enrichment operations to be conducted at the Isotope Enrichment Facility (IEF) will be limited to stable isotopes. Among the positive changes in the enriched stable isotope area are a well-functioning, long-term contract program, which offers stability and pricing advantages; the resumption of calutron operations; the adoption of prorated conversion charges, which greatly improves the pricing of isotopes to small users; ISO 9002 registration of the IEF's quality management system; and a much more customer-oriented business philosophy. Efforts are also being made to restore and improve upon the extensive chemical and physical form processing capablities that once existed in the enriched stable isotope program. Innovative ideas are being pursued in both technical and administrative areas to encourage the beneficial use of enriched stable isotopes and the development of related technologies.

  5. Status of stable isotope enrichment, products, and services at the Oak Ridge National Laboratory

    International Nuclear Information System (INIS)

    Aaron, W.S.; Tracy, J.G.; Collins, E.D.

    1996-01-01

    The Oak Ridge National Laboratory (ORNL) has been supplying enriched stable and radioactive isotopes to the research, medical, and industrial communities for over 50 years. Very significant changes have occurred in this effort over the past several years, and, while many of these changes have had a negative impact on the availability of enriched isotopes, more recent developments are actually improving the situation for both the users and the producers of enriched isotopes. ORNL is still a major producer and distributor of radioisotopes, but future isotope enrichment operations conducted at the Isotope Enrichment Facility (IEF) will be limited to stable isotopes. Among the positive changes in the enriched stable isotope area are a well-functioning, long-term contract program, which offers stability and pricing advantages; the resumption of calutron operations; the adoption of prorated conversion charges, which greatly improves the pricing of isotopes to small users; SIO 9002 registration of the IEF's quality management system; and a much more customer-oriented business philosophy. Efforts are also being made to restore and improve upon the extensive chemical and physical form processing capabilities that once existed in the enriched stable isotope program. Innovative ideas are being pursued in both technical and administrative areas to encourage the beneficial use of enriched stable isotopes and the development of related technologies

  6. Challenging a classic myth: pneumoperitoneum associated with acute diverticulitis is not an indication for open or laparoscopic emergency surgery in hemodynamically stable patients. A 10-year experience with a nonoperative treatment.

    Science.gov (United States)

    Costi, Renato; Cauchy, François; Le Bian, Alban; Honart, Jean-François; Creuze, Nicolas; Smadja, Claude

    2012-07-01

    In patients presenting with acute diverticulitis (AD) and signs of acute peritonitis, the presence of extradigestive air (EDA) on a computer tomography (CT) scan is often considered to indicate the need for emergency surgery. Although the traditional management of "perforated" AD is open sigmoidectomy, more recently, laparoscopic drainage/lavage (usually followed by delayed elective sigmoidectomy) has been reported. The aim of this retrospective study is to evaluate the results of nonoperative management of emergency patients presenting with AD and EDA. The outcomes of 39 consecutive hemodynamically stable patients (23 men, mean age = 54.7 years) who were admitted with AD and EDA and were managed nonoperatively (antibiotic and supportive treatment) at a tertiary-care university hospital between January 2001 and June 2010 were retrospectively collected and analyzed. These included morbidity (Clavien-Dindo) and treatment failure (need for emergency surgery or death). A univariate analysis of clinical, radiological, and laboratory criteria with respect to treatment failure was performed. Results of delayed elective laparoscopic sigmoidectomy were also analyzed. There was no mortality. Thirty-six of the 39 patients (92.3%) did not need surgery (7 patients required CT-guided abscess drainage). Mean hospital stay was 8.1 days. Duration of symptoms, previous antibiotic administration, severe sepsis, PCR level, WBC concentration, and the presence of abdominal collection were associated with treatment failure, whereas "distant" location of EDA and free abdominal fluid were not. Five patients had recurrence of AD and were treated medically. Seventeen patients (47.2%) underwent elective laparoscopic sigmoidectomy for which mean operative time was 246 min (range = 100-450) and the conversion rate was 11.8%. Mortality was nil and the morbidity rate was 41.2%. Mean postoperative stay was 7.1 days (range = 4-23). Nonoperative management is a viable option in most emergency

  7. Hemodynamics in patients with hypertensive intracerebral hemorrhage

    International Nuclear Information System (INIS)

    Kitahara, Tetsuhiro

    1997-01-01

    Cerebral hemodynamics in 15 patients with hypertensive intracerebral hemorrhage (HICH) were evaluated by measuring cerebral blood flow (CBF) and cerebrovascular reserve capacity, using stable xenon-enhanced computed tomography. Their hematomas were removed by stereotactic aqua stream aspiration. The hemispheric and thalamic CBFs of patients with HICH were lower than those of hypertensive patients without hematomas. However, the hemispheric CBF increased according to how much of the hematoma was removed surgically. Thus, hemodynamics in patients with HICH can be improved by surgical hematoma removal, although some adjunct therapies are necessary in order to prevent secondary edema and the delayed neuronal death. (author)

  8. Status of stable enrichment and services at the Oak Ridge National Laboratory

    International Nuclear Information System (INIS)

    Aaron, W.S.; Tracy, J.G.

    1995-01-01

    Enriched stable and radioactive isotopes have played a significant role in the progress of mankind with most of that progress occurring in the last 50 years. The Oak Ridge National Laboratory (ORNL) has been a major contributor to that progress by developing production methods and supplying enriched isotopes to research, medical and commercial users world-wide. The only alternate major source for these materials, especially the stable isotopes, is located in Russia. Over this time period, many changes in the content and form of this function have occurred in response to scientific, commercial, and political influences. Many of these changes have been positive, while some have had a negative impact on the supply and availability of enriched isotopes. What has not changed, however, is the importance of these special materials to virtually all aspects of life

  9. A sign of change in industrial structure under stable growth: economic status of nuclear industry

    International Nuclear Information System (INIS)

    Anon.

    1985-01-01

    The real economical growth rate in fiscal year 1983 in Japan was 3.7 %, and the business trend showed the sign of restoration. The status of primary energy supply in Japan turned to 4.5 % increase as compared with the previous year. Petroleum increased by 3.5 %, coal by 1.6 %, and nuclear power by 11.1 %. As the result, the proportion of petroleum to total primary energy supply slightly decreased to 61 %. Electric power demand increased by 6.3 %, and the proportion of nuclear power to total generated power quantity increased to 20.4 %. As to the status of atomic energy industry in fiscal 1983, one nuclear power plant started the operation, and the construction of three nuclear power plants began. The investment for nuclear fuel cycle was enthusiastic, and the business progressed favorably. The total outlay related to atomic energy was 2.89 trillion yen, 14 % increase as compared with the previous year. The sales of mining and manufacturing industries was 1.367 trillion yen, 17 % increase. The number of workers related to atomic energy was 65,997, 2 % decrease. The mean capacity ratio of the production facilities for atomic energy products in fiscal 1983 was 66.5 %, far below the target 72 %. (Kako, I.)

  10. Disentangling effects of growth and nutritional status on seabird stable isotope ratios

    Science.gov (United States)

    Sears, J.; Hatch, Shyla A.; O'Brien, D. M.

    2009-01-01

    A growing number of studies suggest that an individual's physiology affects its carbon and nitrogen stable isotope signatures, obscuring a signal often assumed to be only a reflection of diet and foraging location. We examined effects of growth and moderate food restriction on red blood cell (RBC) and feather ??15N and ??13C in rhinoceros auklet chicks (Cerorhinca monocerata), a piscivorous seabird. Chicks were reared in captivity and fed either control (75 g/day; n = 7) or ~40% restricted (40 g/day; n = 6) amounts of high quality forage fish. We quantified effects of growth on isotopic fractionation by comparing ??15N and ??13C in control chicks to those of captive, non-growing subadult auklets (n = 11) fed the same diet. To estimate natural levels of isotopic variation, we also collected blood from a random sample of free-living rhinoceros auklet adults and chicks in the Gulf of Alaska (n = 15 for each), as well as adult feather samples (n = 13). In the captive experiment, moderate food restriction caused significant depletion in ??15N of both RBCs and feathers in treatment chicks compared to control chicks. Growth also induced depletion in RBC ??15N, with chicks exhibiting lower ??15N when they were growing the fastest. As growth slowed, ??15N increased, resulting in an overall pattern of enrichment over the course of the nestling period. Combined effects of growth and restriction depleted ??15N in chick RBCs by 0.92???. We propose that increased nitrogen-use efficiency is responsible for 15N depletion in both growing and food-restricted chicks. ??15N values in RBCs of free-ranging auklets fell within a range of only 1.03???, while feather ??15N varied widely. Together, our captive and field results suggest that both growth and moderate food restriction can affect stable isotope ratios in an ecologically meaningful way in RBCs although not feathers due to greater natural variability in this tissue. ?? 2008 Springer-Verlag.

  11. Production technology status and development trend of stable isotopes C, N and O

    International Nuclear Information System (INIS)

    Li Hulin

    2011-01-01

    It has been over half a century since the successful separation of table isotopes carbon, nitrogen and oxygen. The production capacity achieved three levels improvements from the laboratory-scale of one hundred grams, to the pilot production of several kilo- grams, and mass production of one hundred kilograms. The separation technologies also achieved three generation progress. The first generation of separation technology was represented by thermal diffusion method, chromatography, and ion exchange; the second generation of separation technology was represented by chemical exchange, distillation; the third generation of separation technology was characterized by the techniques innovation of material recycling, energy coupling, energy saving, and large-scale production capacity. At present, "1"3C is wholly produced by cryogenic distillation method, "1"5N is produced by NO/HNO_3 chemical exchange and NO cryogenic distillation method, and "1"80 is manufactured by distillation of water, and cryogenic distillation of NO and O_2. The same features of these separation methods are achieving energy coupling, materials recycling, large-scale producing, and energy conservation in the process. In the future, it will be the theme of stable isotope industry to develop environment-friendly, raw materials available, energy saving, low-cost, and large-scale manufacturing technology through continuous technological innovation. (authors)

  12. Revascularization with percutaneous coronary intervention does not affect androgen status in males with chronic stable angina pectoris.

    Science.gov (United States)

    Gosai, J N; Charalampidis, P; Nikolaidou, T; Parviz, Y; Morris, P D; Channer, K S; Jones, T H; Grech, E D

    2016-05-01

    There is a clear association between low serum testosterone and coronary artery disease (CAD) in men. Hypotestosteronaemia is associated with accelerated atherosclerosis and a quarter of men with CAD are biochemically hypogonadal. Amongst those with CAD, hypotestosteronaemia is associated with increased mortality. Testosterone vasodilates coronary arteries, and exogenous testosterone reduces ischaemia. Whether hypotestosteronaemia is a cause or a consequence of CAD remains unanswered. The aim of this prospective observational study was to investigate whether coronary revascularization affected androgen status in men with stable angina pectoris. Twenty five men (mean age 62.7, SD 9.18) with angiographically significant CAD and symptomatic angina underwent full coronary revascularization by percutaneous coronary intervention. Androgen status and symptoms of angina, stress, depression and sexual function were assessed before, and at one and 6 months after the coronary revascularization. All patients underwent complete revascularization which was associated with a significant reduction in angina symptoms and ischaemia. No significant difference was seen in total testosterone (11.33 nmol/L baseline; 12.56, 1 month post; 13.04 at 6 months; p = 0.08). A significant and sustained rise in sex hormone-binding globulin was seen (33.99 nm/L baseline; 36.11 nm/L 1 month post PCI; 37.94 nm/L at 6 months; p = 0.03) Overall, there was no significant alteration in any other marker of androgen status including free testosterone or bioavailable testosterone. There was no change in symptoms of anxiety, depression or sexual function. Coronary revascularization has no sustained effect on androgen status. This supports the hypothesis that hypotestosteronaemia is not a consequence of angina pectoris or myocardial ischaemia. © 2016 American Society of Andrology and European Academy of Andrology.

  13. Stable isotope aided evaluation of Community Nutrition Program: effect of food supplementation schemes on maternal and infant nutritional status

    International Nuclear Information System (INIS)

    Sarr Cisse, Aita; Dossou, Nicole; Ndiaye, Mamadou

    2002-01-01

    The supplementation program of the community nutrition project (PNC) launched by the Senegalese Government in order to protect the most vulnerable groups (children and women) was evaluated. Using a stable isotope (deuterium), we assessed the effect of the PNC on breastmilk output, mother's body composition, and baby's growth at three months of lactation. Breastmilk triglycerides, lactose, protein, and zinc were also determined. Mothers who were supplemented more than 60 days during pregnancy showed a significant increase in fot- free mass as compared to those who were supplemented for less than 30 days (p= .03). Breastmilk output was not influenced by the supplementation, but breastmilk lactose, total protein, and zinc contents increased significantly (p < .01) in the supplemented mothers. Growth of the babies of the supplemented mothers was better than that of those whose mothers were not supplemented. It was concluded that the food supplementation had beneficial effects on both mothers' and babies' nutritional status depending on the onset of the supplementation.

  14. Prognostic impact of nutritional status assessed by the Controlling Nutritional Status score in patients with stable coronary artery disease undergoing percutaneous coronary intervention.

    Science.gov (United States)

    Wada, Hideki; Dohi, Tomotaka; Miyauchi, Katsumi; Doi, Shinichiro; Konishi, Hirokazu; Naito, Ryo; Tsuboi, Shuta; Ogita, Manabu; Kasai, Takatoshi; Okazaki, Shinya; Isoda, Kikuo; Suwa, Satoru; Daida, Hiroyuki

    2017-11-01

    Recently, malnutrition has been shown to be related to worse clinical outcomes in patients with heart failure. However, the association between nutritional status and clinical outcomes in patients with coronary artery disease (CAD) remains unclear. We investigated the prognostic value of malnutrition assessed by the Controlling Nutritional Status (CONUT; range 0-12, higher = worse, consisting of serum albumin, cholesterol and lymphocytes) score in patients with CAD. The CONUT score was measured on admission in a total of 1987 patients with stable CAD who underwent elective percutaneous coronary intervention (PCI) between 2000 and 2011. Patients were divided into two groups according to their CONUT score (0-1 vs. ≥2). The incidence of major adverse cardiac events (MACE), including all-cause death and non-fatal myocardial infarction, was evaluated. The median CONUT score was 1 (interquartile range 0-2). During the median follow-up of 7.4 years, 342 MACE occurred (17.2%). Kaplan-Meier curves revealed that patients with high CONUT scores had higher rates of MACE (log-rank p < 0.0001). High CONUT scores showed a significant increase in the incidence of MACE compared with low CONUT scores, even after adjusting for confounding factors (hazard ratio: 1.64, 95% confidence interval 1.30-2.07, p < 0.0001). Adding CONUT scores to a baseline model with established risk factors improved the C-index (p = 0.02), net reclassification improvement (p = 0.004) and integrated discrimination improvement (p = 0.0003). Nutritional status assessed by the CONUT score was significantly associated with long-term clinical outcomes in patients with CAD. Pre-PCI assessment of the CONUT score may provide useful prognostic information.

  15. Obesity and renal hemodynamics

    NARCIS (Netherlands)

    Bosma, R. J.; Krikken, J. A.; van der Heide, J. J. Homan; de Jong, P. E.; Navis, G. J.

    2006-01-01

    Obesity is a risk factor for renal damage in native kidney disease and in renal transplant recipients. Obesity is associated with several renal risk factors such as hypertension and diabetes that may convey renal risk, but obesity is also associated with an unfavorable renal hemodynamic profile

  16. [Effect of complex sanatorium treatment including magnetotherapy on hemodynamics in patients with arterial hypertension].

    Science.gov (United States)

    Efremushkin, G G; Duruda, N V

    2003-01-01

    Forty nine patients with arterial hypertension of stage I-II received combined sanatorium treatment. Of them, 21 had adjuvant total magnetotherapy. All the patients were examined for parameters of central, cerebral hemodynamics and microcirculation. The adjuvant magnetotherapy produced a beneficial effect on hypertension: clinical symptoms attenuated, arterial pressure became more stable, hemodynamics improved, duration of hospitalization reduced, requirement in hypotensive drugs diminished.

  17. Cerebrovascular Hemodynamics in Women.

    Science.gov (United States)

    Duque, Cristina; Feske, Steven K; Sorond, Farzaneh A

    2017-12-01

    Sex and gender, as biological and social factors, significantly influence health outcomes. Among the biological factors, sex differences in vascular physiology may be one specific mechanism contributing to the observed differences in clinical presentation, response to treatment, and clinical outcomes in several vascular disorders. This review focuses on the cerebrovascular bed and summarizes the existing literature on sex differences in cerebrovascular hemodynamics to highlight the knowledge deficit that exists in this domain. The available evidence is used to generate mechanistically plausible and testable hypotheses to underscore the unmet need in understanding sex-specific mechanisms as targets for more effective therapeutic and preventive strategies. Thieme Medical Publishers 333 Seventh Avenue, New York, NY 10001, USA.

  18. 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...

  19. Comparison of Hemodynamic Changes during General Anesthesia with Low-dose Isoflurane or Propofol in Elderly Patients Undergoing Upper Femoral Surgery

    Directory of Open Access Journals (Sweden)

    Mir Mohammad Taghi Mortazavi

    2016-01-01

    Full Text Available Background & objectives: Surgery of upper part of femor in elderly patients can be due to the fracture of femoral neck, shaft and arthroplasty. Hemodynamic changes and complications of the anesthesia are among the major concerns. The aim of this study was to compare the hemodynamic changes in low dose isoflurane with propofol in upper femoral surgeries in elderly patients. Methods: This prospective clinical trial study was done on 60 patients over 65 year-old elderly patients with ASA physical status of I and II that were candidate for upper femoral surgery in two groups (inhalational: isoflurane 0.5-0.6 MAC and (total intravenous anesthesia with propofol 50-100 mic/kg/min. Hemodynamic changes were compared in these groups with the same anesthetic depth (HR-SBP-DBP-MBP-SaO₂. Results: There was no significant difference in heart rate, age or sex between two groups. In isoflurane group SBP on 20 and 25th minutes and DBP and MBP on 20, 25 and 35th minutes were significantly higher than propofol group. In propofol group SaO₂ was significantly more than isoflurane group on induction, start of surgery and on 5, 25, 35 and 45th minutes of surgery. Conclusion: In anesthesia with the same Bi-Spectral Index, isoflurane provides more stable hemodynamic parameters than propofol.

  20. [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.

  1. Natriuretic peptides and cerebral hemodynamics

    DEFF Research Database (Denmark)

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

    2014-01-01

    Natriuretic peptides have emerged as important diagnostic and prognostic tools for cardiovascular disease. Plasma measurement of the bioactive peptides as well as precursor-derived fragments is a sensitive tool in assessing heart failure. In heart failure, the peptides are used as treatment...... 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...

  2. Echocardiographic Evaluation of Hemodynamics in Neonates and Children

    Directory of Open Access Journals (Sweden)

    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

  3. Lagrangian postprocessing of computational hemodynamics.

    Science.gov (United States)

    Shadden, Shawn C; Arzani, Amirhossein

    2015-01-01

    Recent advances in imaging, modeling, and computing have rapidly expanded our capabilities to model hemodynamics in the large vessels (heart, arteries, and veins). This data encodes a wealth of information that is often under-utilized. Modeling (and measuring) blood flow in the large vessels typically amounts to solving for the time-varying velocity field in a region of interest. Flow in the heart and larger arteries is often complex, and velocity field data provides a starting point for investigating the hemodynamics. This data can be used to perform Lagrangian particle tracking, and other Lagrangian-based postprocessing. As described herein, Lagrangian methods are necessary to understand inherently transient hemodynamic conditions from the fluid mechanics perspective, and to properly understand the biomechanical factors that lead to acute and gradual changes of vascular function and health. The goal of the present paper is to review Lagrangian methods that have been used in post-processing velocity data of cardiovascular flows.

  4. THE INFLUENCE OF SOCIAL STATUS AND ETHNICITY ON DIET IN MEDIAEVAL TALLINN AS SEEN THROUGH STABLE ISOTOPE ANALYSIS

    DEFF Research Database (Denmark)

    Lightfoot, Emma; Naum, Magdalena; Kadakas, Villu

    2016-01-01

    , for comparative purposes. The individuals were investigated using carbon, nitrogen and oxygen stable isotope analysis. The results indicate that while all analysed individuals consumed diets based on C3 plants and animals consuming C3 plants, some individuals also consumed small amounts of C4 plants (likely......Food encodes social and cultural values and has an important role to play in defining identities. In mixed populations, diet can be used to distinguish between ‘us’ and ‘them’. This study investigates the extent to which the inhabitants of mediaeval Tallinn, an important trading centre, used food...... millet) or seafood. C 4 plants were consumed by the urban residents buried at the Church of the Holy Spirit and one or two individuals from Sulevimägi. It is thought that millet was an imported food consumed by the middle class. Marine foods were consumed by the individuals at St Catherine’s Church...

  5. Corrective Surgery for Congenital Scoliosis Associated with Split Cord Malformation: It May Be Safe to Leave Diastematomyelia Untreated in Patients with Intact or Stable Neurological Status.

    Science.gov (United States)

    Shen, Jianxiong; Zhang, Jianguo; Feng, Fan; Wang, Yipeng; Qiu, Guixing; Li, Zheng

    2016-06-01

    The treatment of congenital scoliosis associated with split cord malformation (SCM) raises the issue of how to best manage such patients to avoid neurological deficit while achieving a satisfactory correction. This prospective clinical study was performed at our center from March 2000 through June 2013. We enrolled a total of 214 patients (61 male and 153 female) with congenital scoliosis associated with SCM who were undergoing spinal correction surgery. The mean age at surgery was 14.1 years. The inclusion criteria were congenital scoliosis with confirmed SCM; status as neurologically intact or stable over the preceding 2 years; and no neurological deterioration as evidenced on traction, side-bending, or fulcrum-bending radiographs. Patients with unstable neurological status or for whom vertebral column resection surgery was planned were excluded. All patients underwent scoliosis surgery without prophylactic detethering. On the basis of the Pang classification, 73 patients were in the type-I SCM group, and 141 were in the type-II SCM group. The groups did not differ significantly with respect to preoperative characteristics, operative time, blood loss, or number of levels fused. The mean follow-up was 37 months (range, 24 to 108 months). The rate of scoliosis correction was lower in the type-I group than in the type-II group (p patients experienced transient neurological complications, with no significant difference between the groups (p = 0.415). No patient experienced permanent neurological deficit during surgery or follow-up. Patients with congenital scoliosis associated with SCM, regardless of type, can safely and effectively undergo spinal deformity correction and achieve spinal balance without neurological intervention. For such patients with intact or stable neurological status, prophylactic detethering prior to scoliosis surgery may not be necessary. Therapeutic Level II. See Instructions for Authors for a complete description of levels of evidence

  6. 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...

  7. Childhood moyamoya disease: hemodynamic MRI

    Energy Technology Data Exchange (ETDEWEB)

    Tzika, A.A. [Department of Radiology, Children`s Hospital and Harvard Medical School, 300 Longwood Avenue, Boston, MA 02115 (United States); Robertson, R.L. [Department of Radiology, Children`s Hospital and Harvard Medical School, 300 Longwood Avenue, Boston, MA 02115 (United States); Barnes, P.D. [Department of Radiology, Children`s Hospital and Harvard Medical School, 300 Longwood Avenue, Boston, MA 02115 (United States); Vajapeyam, S. [Department of Radiology, Children`s Hospital and Harvard Medical School, 300 Longwood Avenue, Boston, MA 02115 (United States); Burrows, P.E. [Department of Radiology, Children`s Hospital and Harvard Medical School, 300 Longwood Avenue, Boston, MA 02115 (United States); Treves, S.T. [Department of Radiology, Children`s Hospital and Harvard Medical School, 300 Longwood Avenue, Boston, MA 02115 (United States); Scott, R.M. l [Department of Radiology, Children`s Hospital and Harvard Medical School, 300 Longwood Avenue, Boston, MA 02115 (United States)

    1997-09-01

    Background. Childhood moyamoya disease is a rare progressive cerebrovascular disease. Objective. To evaluate cerebral hemodynamics using dynamic Gd-DTPA-enhanced imaging in children with moyamoya disease. Materials and methods. Eight children (2-11 years of age) with the clinical and angiographic findings typical of moyamoya disease, before and/or after surgical intervention (pial synangiosis), underwent conventional MR imaging (MRI) and hemodynamic MR imaging (HMRI). HMRI used a spoiled gradient-echo with low flip angle (10 deg) and long TE (TR/TE = 24/15 ms) to minimize T 1 effects and emphasize T 2{sup *} weighting. Raw and calculated hemodynamic images were reviewed. Three-dimensional time-of-flight MR angiography (MRA) and perfusion brain single photon emission computed tomography (SPECT) were also performed. Results. Abnormal hemodynamic maps resulting from vascular stenosis or occlusion and basal collaterals were observed in six patient studies. HMRI depicted perfusion dynamics of affected cerebrovascular territories, detected cortical perfusion deficits, and complemented conventional MRI and MRA. HMRI findings were consistent with those of catheter angiography and perfusion SPECT. Conclusion. Our preliminary experience suggests that HMRI may be of value in the preoperative and postoperative evaluation of surgical interventions in moyamoya disease. (orig.). With 4 figs., 3 tabs.

  8. Childhood moyamoya disease: hemodynamic MRI

    International Nuclear Information System (INIS)

    Tzika, A.A.; Robertson, R.L.; Barnes, P.D.; Vajapeyam, S.; Burrows, P.E.; Treves, S.T.; Scott, R.M. I

    1997-01-01

    Background. Childhood moyamoya disease is a rare progressive cerebrovascular disease. Objective. To evaluate cerebral hemodynamics using dynamic Gd-DTPA-enhanced imaging in children with moyamoya disease. Materials and methods. Eight children (2-11 years of age) with the clinical and angiographic findings typical of moyamoya disease, before and/or after surgical intervention (pial synangiosis), underwent conventional MR imaging (MRI) and hemodynamic MR imaging (HMRI). HMRI used a spoiled gradient-echo with low flip angle (10 deg) and long TE (TR/TE = 24/15 ms) to minimize T 1 effects and emphasize T 2 * weighting. Raw and calculated hemodynamic images were reviewed. Three-dimensional time-of-flight MR angiography (MRA) and perfusion brain single photon emission computed tomography (SPECT) were also performed. Results. Abnormal hemodynamic maps resulting from vascular stenosis or occlusion and basal collaterals were observed in six patient studies. HMRI depicted perfusion dynamics of affected cerebrovascular territories, detected cortical perfusion deficits, and complemented conventional MRI and MRA. HMRI findings were consistent with those of catheter angiography and perfusion SPECT. Conclusion. Our preliminary experience suggests that HMRI may be of value in the preoperative and postoperative evaluation of surgical interventions in moyamoya disease. (orig.). With 4 figs., 3 tabs

  9. [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.

  10. [Cerebral hemodynamics in patients with neurosensory hearing loss before and after magnetotherapy].

    Science.gov (United States)

    Morenko, V M; Enin, I P

    2001-01-01

    Magnetotherapy effects on cerebral hemodynamics were studied using rheoencephalography (REG). When the treatment results and changes in cerebral hemodynamics were compared it was evident that normalization or improvement of vascular status in vertebrobasilar and carotid territories registered at REG results in better hearing. This confirms the role of vascular factor in pathogenesis of neurosensory hypoacusis of different etiology and effectiveness of magnetotherapy in such patients.

  11. Hemodynamics in Korean Hemorrhagic Fever

    International Nuclear Information System (INIS)

    Han, Ji Young; Lee, Jung Sang; Koh, Chang Soon; Lee, Mun Ho

    1974-01-01

    The author in an attempt to evaluate hemodynamic changes in the clinical stages of Korean hemorrhagic fever measured plasma volume, cardiac output and effective renal plasma flow utilizing radioisoto as during various phases of the disease. Cardiac output was measured by radiocardiography with external monitoring method using RIHSA. Effective renal plasma flow was obtained from blood clearance curve drawn by external monitoring after radiohippuran injection according to the method described by Razzak et al. The study was carried out in thirty-eight cases of Korean hemorrhagic fever and the following conclusions were obtained. 1) Plasma volume was increased in the patients during the oliguric and hypertensive-diuretic phases, while it was normal in the patients during the normotensive-diuretic phase. 2) Cardiac index was increased in the patients during the oliguric phase and was slightly increased in the patients at the hypertensive diuretic phase. It was normal in the other phases. 3) Total peripheral resistance was increased in the hypertensive patients during diuretic phase, while it was normal in the rest of phases. 4) Effective renal plasma flow was significantly reduced in the patients during the oliguric and diuretic phases as well as at one month after the oliguric onset. There was no significant difference between the oliguric and the early diuretic phases. Renal plasma flow in the group of patients at one month after the oliguric onset was about 45% of the normal, however, it returned to normal level at six months after the onset. 5) Clinical syndrome of relative hypervolemia was observed in some patients during the oliguric phase or hypertensive diuretic phase. Characteristic hemodynamic findings were high cardiac output and normal to relatively increased peripheral resistance these cases. Relatively increased circulating blood volumes due to decreased effective vascular space was suggested for the mechanism of relative hypervolemia. 6) Cardiac

  12. Impact of Intra-Extracranial Hemodynamics on Cerebral Ischemia by Arterial Hypertension (Part 2

    Directory of Open Access Journals (Sweden)

    Alexander G. Kruglov, PhD, ScD

    2012-06-01

    Full Text Available The association between hemodynamic and biochemical parameters of cerebral blood flow have been studied in man, using mathematical methods of statistics. The values have been obtained through catheterization using a probe jammed at the level of the bulb of the superior jugular vein. Relationships with central hemodynamic parameters have been evaluated, including the right atrium, the right ventricle, and the left ventricle, as well as with pressure and biochemical values of the arterial bed. Data have been acquired in patients with stable arterial hypertension. Analysis of all relationship between hemodynamic and biochemical parameters has shown that the uniform hemodynamic zone: Sin.P. – SJV – SEV – the right atrium, normally participates in regulation of gaseous exchange in the human brain depending on the minimum pressure on the way of outflow from the brain. In stable arterial hypertension, this type of regulation is lost. On the basis of the results of this study, it has been concluded that blood viscosity is normally a primary controlled parameter of homeostasis. In stable arterial hypertension, homeostatic control of factors determining rheological and thrombogenic properties of blood, as well as participating in the development of brain ischemic conditions is lost. This increases risk of disturbances in central hemodynamics.

  13. Hemodynamic response during aneurysm clipping surgery among experienced neurosurgeons.

    Science.gov (United States)

    Bunevicius, Adomas; Bilskiene, Diana; Macas, Andrius; Tamasauskas, Arimantas

    2016-02-01

    Neurosurgery is a challenging field associated with high levels of mental stress. The goal of this study was to investigate the hemodynamic response of experienced neurosurgeons during aneurysm clipping surgery and to evaluate whether neurosurgeons' hemodynamic responses are associated with patients' clinical statuses. Four vascular neurosurgeons (all male; mean age 51 ± 10 years; post-residency experience ≥7 years) were studied during 42 aneurysm clipping procedures. Blood pressure (BP) and heart rate (HR) were assessed at rest and during seven phases of surgery: before the skin incision, after craniotomy, after dural opening, after aneurysm neck dissection, after aneurysm clipping, after dural closure and after skin closure. HR and BP were significantly greater during surgery relative to the rest situation (p ≤ 0.03). There was a statistically significant increase in neurosurgeons' HR (F [6, 41] = 10.88, p neurosurgeon experience, the difference in BP as a function of aneurysm rupture was not significant (p > 0.08). Aneurysm location, intraoperative aneurysm rupture, admission WFNS score, admission Glasgow Coma Scale scores and Fisher grade were not associated with neurosurgeons' intraoperative HR and BP (all p > 0.07). Aneurysm clipping surgery is associated with significant hemodynamic system activation among experienced neurosurgeons. The greatest HR and BP were after aneurysm neck dissection and clipping. Aneurysm location and patient clinical status were not associated with intraoperative changes of neurosurgeons' HR and BP.

  14. Cerebral hematocrit decreases with hemodynamic compromise in carotid artery occlusion: a PET study.

    Science.gov (United States)

    Yamauchi, H; Fukuyama, H; Nagahama, Y; Katsumi, Y; Okazawa, H

    1998-01-01

    This study investigated whether in patients with internal carotid artery occlusion the regional cerebral hematocrit correlates with cerebral hemodynamics or metabolic state and, if so, how the regional cerebral hematocrit changes in the hemodynamically compromised region. We used positron emission tomography to study seven patients with unilateral internal carotid artery occlusion and no cortical infarction in the chronic stage. The distributions of red blood cell and plasma volumes were assessed using oxygen-15-labeled carbon monoxide and copper-62-labeled human serum albumin-dithiosemicarbazone tracers, respectively. The calculated hematocrit value was compared with the hemodynamic and metabolic parameters measured with the oxygen-15 steady-state technique. In the cerebral cortex, the value of the cerebral hematocrit varied but was correlated with the hemodynamic and metabolic status. Stepwise regression analysis revealed that the large vessel hematocrit, the cerebral metabolic rate of oxygen, and the cerebral blood flow or the oxygen extraction fraction accounted for a significant proportion of variance of the cerebral hematocrit. The oxygen extraction fraction and the cerebral metabolic rate of oxygen negatively correlated with the cerebral hematocrit, whereas the cerebral blood flow correlated positively: patients with reduced blood supply relative to metabolic demand (decreased blood flow with increased oxygen extraction fraction) showed low hematocrit values. In carotid artery occlusion in the chronic stage, regional cerebral hematocrit may vary according to cerebral hemodynamics and metabolic status. Regional cerebral hematocrit may decrease with hemodynamic compromise unless oxygen metabolism concomitantly decreases.

  15. [The evaluation of nutritional status of stable COPD patients and to investigate the effect of nutritional status on perception of dyspnea, exercise capacity, body composition, hospitalisation and life quality].

    Science.gov (United States)

    Ayar Karakoç, Gamze; Ernam, Dilek; Aka Aktürk, Ülkü; Öztaş, Selahattin; Oğur, Erhan; Kabadayı, Feyyaz

    2016-06-01

    Malnutrition is a comorbidity oftenly seen in COPD patients who have progressive chronic inflammation and severity. In this prospective study, we aimed to determine the nutritional status of stable COPD patients and to investigate the impact of nutritional status on perception of dyspnoea, exercise capacity, body composition, hospitalisation and life quality. COPD patients were assessed using previous smoking story, physical examination and irreversible airway obstruction. This study was done with 50 COPD patients older than 65 years of age and 30 control subjects. Exclusion criteria were also the co-existance of malignancies, malabsorbtion, DM, neurological diseases, renal failure and unstable cardiac diseases known to influence the nutritional state. The obstruction degree was evaluated by spirometry, nutritional status was classified by the MNA questionnaire, perception of dyspnoea was assessed by the MMRC scale, exercise capacity was assessed by the 6MWT, life quality was assessed by the CAT scale. Body composition parameters FM, FFM and FMI were analyzed and hospitalisations during 6 months after discharge were recorded. The COPD patients were divided into three groups as without malnutrition (n= 25,%50), under risk of malnutrition (n= 19,%38) and malnourished (n= 6,%12). The COPD severity, MMRC dyspnoea score, CAT score and hospitalisations during 6 months following were higher among the malnourished patients. On the other hand, body mass index, 6MWT results, FM and FFM were lower in malnourished patients. A positive correlation between FFM and 6MWT and a negative correlation between FFM and hospitalisation were observed. MNA is a well-developed questionnaire which evaluates malnutrition in COPD patients. We determined that malnourished COPD patients have higher airway obstruction degree, perception of dyspnoea, CAT score and lower exercise capacity and FFM. FFM is an independent predictor of exercise capacity and rehospitalisation during 6 months.

  16. 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.

  17. Hemodynamics in diabetic orthostatic hypotension

    DEFF Research Database (Denmark)

    Hilsted, J; Parving, H H; Christensen, N J

    1981-01-01

    Hemodynamic variables (blood pressure, cardiac output, heart rate, plasma volume, splanchnic blood flow, and peripheral subcutaneous blood flow) and plasma concentrations of norepinephrine, epinephrine, and renin were measured in the supine position and after 30 min of quiet standing. This was done...... in normal subjects (n = 7) and in juvenile-onset diabetic patients without neuropathy (n = 8), with slight neuropathy (decreased beat-to-beat variation in heart rate during hyperventilation) (n = 8), and with severe neuropathy including orthostatic hypotension (n = 7). Blood pressure decreased precipitously...

  18. The effect of tourniquet deflation on hemodynamics and regional cerebral oxygen saturation in aged patients undergoing total knee replacement surgery

    OpenAIRE

    Song, Inkyung; Kim, Dong Yeon; Kim, Youn Jin

    2012-01-01

    Background Inflation and deflation of a pneumatic tourniquet used in total knee replacement surgery induces various changes in patient's hemodynamic and metabolic status, which may result in serious complications, especially in aged patients. Near-infrared spectroscopy (NIRS) is a monitoring device designed to estimate the regional cerebral oxygen saturation. We evaluated the effect of tourniquet deflation on hemodynamics and regional cerebral oxygen saturation in aged patients undergoing tot...

  19. Stable isotopes

    International Nuclear Information System (INIS)

    Evans, D.K.

    1986-01-01

    Seventy-five percent of the world's stable isotope supply comes from one producer, Oak Ridge Nuclear Laboratory (ORNL) in the US. Canadian concern is that foreign needs will be met only after domestic needs, thus creating a shortage of stable isotopes in Canada. This article describes the present situation in Canada (availability and cost) of stable isotopes, the isotope enrichment techniques, and related research programs at Chalk River Nuclear Laboratories (CRNL)

  20. Non invasive adjustment of fluid status in critically ill patients on renal replacement therapy. Role of Electrical Cardiometry

    Directory of Open Access Journals (Sweden)

    Khaled Hamed Mahmoud

    2016-08-01

    Full Text Available Background: Electrical Cardiometry allows measurement of fluid status using thoracic fluid content (TFC, cardiac output, cardiac index, systemic vascular resistance index which could be ideal noninvasive hemodynamic monitoring for patients undergoing hemodialysis (HD. Objectives: Investigating the relation between changes in TFC and amount of fluid removal during HD session and to monitor hemodynamic parameters to avoid episodes of hemodynamic compromise during HD session. Methods: Thirty critically ill patients on HD were enrolled. Clinical assessment of volume overload and hemodynamics (BP, MAP, CVP, monitored by Electrical Cardiometry ICON® before HD and all through sessions. Results: Out of studied patients males represented 46.7% (n = 14 with mean age 48 ± 16 years. There was positive correlation between UF volume and TFC (r = 0.410, P = 0.025. Out of the 30 pts studied 18 pts (60% were hemodynamically stable vs 12 pts (40% that had hypotension represented by non responders group and had lower TFC compared to the hemodynamically stable group (26.45 kohm−1 vs 37.8 kohm−1 with P value of 0.004 indicating that they were hypovolemic. Out of the 30 pts studied 18 pts (60% weren’t congested vs 12 pts (40% remained persistently congested after accomplishing HD session with significantly higher TFC when compared to those who got rid of congestion (43.14 ± 9.9 kohm−1 vs 25.44 ± 5.5 kohm−1 with P value of 0.0001 indicating that they were still hypervolemic. Using analysis of ROC curve TFC at 25.34 kohm−1 was a significant predictor of hypotension with P value of 0.002, AUC 83.4%, sensitivity 67% and specificity 100%. Also TFC cutoff value predicting persistent congestion was 37.02 kohm−1 with P value of 0.0001, AUC 95.8%, sensitivity 83% and specificity 100%. Conclusion: Electrical Cardiometry is an evolving noninvasive tool for adjusting fluid status of critically ill patient on RRT using thoracic fluid

  1. Immunologic, hemodynamic, and adrenal incompetence in cirrhosis

    DEFF Research Database (Denmark)

    Risør, Louise Madeleine; Bendtsen, Flemming; Møller, Søren

    2015-01-01

    dysfunction, but is not responsive to volume expansion. Recent research indicates that development of hepatic nephropathy represents a continuous spectrum of functional and structural dysfunction and may be precipitated by the inherent immunologic, adrenal, and hemodynamic incompetence in cirrhosis. New...... research explores several new markers of renal dysfunction that may replace serum creatinine in the future and give new insight on the hepatic nephropathy. Our understanding of the pathophysiological mechanisms causing the immunologic, adrenal, and hemodynamic incompetence, and the impact on renal...

  2. 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.

  3. 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.

  4. 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...... monitoring of the patients during OLT is addressed with focus on maintaining the patients' central blood volume (CBV) and methods and devices that can serve that purpose are listed. It is considered that a stable CBV maintains cerebral blood flow and oxygenation and thereby the well-being of the patient......, while even a small reduction in blood pressure affects cerebral blood flow and oxygenation if it reflects a reduced CBV and thereby cardiac output. In that regard it is accepted that for the patient going through OLT cardiac output (~8 L/min-1) and also venous oxygen saturation (~85%) are larger than...

  5. 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)

  6. 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

  7. Acute effects of chewing tobacco on coronary microcirculation and hemodynamics in habitual tobacco chewers

    Directory of Open Access Journals (Sweden)

    Vikas Thakran

    2015-01-01

    Full Text Available Background: Long-term adverse cardiovascular effects of smokeless tobacco are well established, however, the effect of chewing tobacco on coronary microcirculation and hemodynamic have not been studied. We intended to analyze the acute effect of chewing tobacco on coronary microcirculation and hemodynamics in habitual tobacco chewers with stable coronary artery disease undergoing elective percutaneous coronary intervention (PCI. Materials and Methods: We prospectively enrolled seven habitual tobacco chewers with stable coronary artery disease with single vessel disease or double vessel disease satisfying the criteria for elective PCI. Patients were instructed to keep 1 g of crushed dried tobacco leaves in the mouth after a successful PCI. Lesion in last stented vessels was evaluated for fractional flow reserve (FFR, coronary flow reserve (CFR, and index of microcirculatory resistance (IMR post-PCI, after 15 min and 30 min of tobacco chewing along with the measurement of serum cotinine levels. Results: Oral tobacco led to high levels of cotinine in the majority of patients. There was an insignificant rise in heart rate, systolic and diastolic blood pressure following tobacco consumption. Baseline CFR (median 1.6, range 1.1–5.5 was low in tobacco chewers after PCI even after optimum FFR (0.9 ± 0.05 in the majority of patients suggesting abnormal microvascular hemodynamics (high IMR in 3 patients, overall median 14.2, range 7–36.2. However, there was no significant change in the estimated CFR or IMR values following tobacco chewing. One patient had bradycardia and hypotension which may be related to vagal reaction or acute nicotine poisoning. Conclusion: Tobacco chewers have abnormal coronary microcirculation hemodynamics even following a successful PCI. However, the coronary micocirculation and hemodynamics do not change acutely following tobacco chewing despite high serum cotinine concentrations.

  8. Unpredictably Stable

    DEFF Research Database (Denmark)

    Failla, Virgilio; Melillo, Francesca; Reichstein, Toke

    2014-01-01

    Is entrepreneurship a more stable career choice for high employment turnover individuals? We find that a transition to entrepreneurship induces a shift towards stayer behavior and identify job matching, job satisfaction and lock-in effects as main drivers. These findings have major implications...

  9. The role of nitrates, beta blockers, and calcium antagonists in stable angina pectoris.

    Science.gov (United States)

    Chan, P K; Heo, J Y; Garibian, G; Askenase, A; Segal, B L; Iskandrian, A S

    1988-09-01

    Numerous controlled studies have shown that nitrates, beta blockers, and calcium antagonists are effective in the treatment of stable angina pectoris. The pharmacokinetics, pharmacodynamics, and hemodynamic effects of these agents are different, and thus combination therapy offers additive improvement and also counterbalancing of the undesirable side effects of each drug. The choice of therapy depends on the severity of symptoms, associated diseases, compliance, side effects, and status of left ventricular function. The main mechanism of improvement is a decrease in myocardial oxygen consumption, though an increase in coronary blood flow is another potential reason for the use of calcium blockers. This review considers the properties of these drugs, their mechanism of action, and the results of randomized studies.

  10. The effect of tourniquet deflation on hemodynamics and regional cerebral oxygen saturation in aged patients undergoing total knee replacement surgery.

    Science.gov (United States)

    Song, Inkyung; Kim, Dong Yeon; Kim, Youn Jin

    2012-11-01

    Inflation and deflation of a pneumatic tourniquet used in total knee replacement surgery induces various changes in patient's hemodynamic and metabolic status, which may result in serious complications, especially in aged patients. Near-infrared spectroscopy (NIRS) is a monitoring device designed to estimate the regional cerebral oxygen saturation. We evaluated the effect of tourniquet deflation on hemodynamics and regional cerebral oxygen saturation in aged patients undergoing total knee replacement surgery, using NIRS. Twenty-eight American Society of Anesthesiologists physical status I or II patients, over the age of sixty-five years undergoing total knee replacement surgery, were included. Under general anesthesia, the mean arterial pressure (MAP), heart rate (HR), cardiac output (CO), stroke volume (SV), and regional cerebral oxygen saturation (rSO(2)) were recorded before induction of anesthesia and every 2 min after tourniquet deflation for 20 min. Arterial blood gas analysis was performed 5 min before, in addition to 0, and 10 min after tourniquet deflation. The decrease of rSO(2) was not significant during 20-min deflation period. MAP, CO and SV showed significant decrease during 2 to 12, 4 to 6 and 2 to 6-min period after tourniquet deflation, respectively (P deflation caused significant changes in hemodynamic and metabolic status, but not in regional cerebral oxygen saturation. It is recommended to monitor neurologic status, as well as hemodynamic and metabolic status to avoid serious complications, especially in aged patients.

  11. Periodontal status affects C-reactive protein and lipids in patients with stable heart disease from a tertiary care cardiovascular clinic.

    Science.gov (United States)

    Flores, Manuela F; Montenegro, Marlon M; Furtado, Mariana V; Polanczyk, Carisi A; Rösing, Cassiano K; Haas, Alex N

    2014-04-01

    There are scarce data on the impact of the periodontal condition in the control of biomarkers in patients with cardiovascular disease (CVD). The aim of this study is to assess whether periodontal inflammation and tissue breakdown are associated with C-reactive protein (CRP) and lipids in patients with stable heart disease. This cross-sectional study included 93 patients with stable coronary artery disease (57 males; mean age: 63.5 ± 9.8 years) who were in outpatient care for at least 6 months. After applying a structured questionnaire, periodontal examinations were performed by two calibrated periodontists in six sites per tooth at all teeth. Blood samples were collected from patients on the day of periodontal examination to determine levels of CRP, lipids, and glycated hemoglobin. Multiple linear regression models were fitted to evaluate the association among different periodontal and blood parameters controlling for sex, body mass index, glycated hemoglobin, use of oral hypoglycemic drugs, and smoking. Overall, the sample presented high levels of periodontal inflammation and tissue breakdown. Unadjusted mean concentrations of triglycerides (TGs), very-low-density lipoprotein cholesterol, and glucose were significantly higher in individuals with severe periodontitis. When multiple linear regression models were applied, number of teeth with clinical attachment loss ≥6 mm and presence of severe periodontitis were significantly associated with higher CRP concentrations. Bleeding on probing was significantly associated with TGs, total cholesterol, and non-high-density lipoprotein cholesterol. In this sample of patients with stable CVD, current periodontal inflammation and tissue breakdown are associated with cardiovascular inflammatory markers, such as CRP and lipid profile.

  12. Symptom-Hemodynamic Mismatch and Heart Failure Event Risk

    Science.gov (United States)

    Lee, Christopher S.; Hiatt, Shirin O.; Denfeld, Quin E.; Mudd, James O.; Chien, Christopher; Gelow, Jill M.

    2014-01-01

    Background Heart failure (HF) is a heterogeneous condition of both symptoms and hemodynamics. Objective The goal of this study was to identify distinct profiles among integrated data on physical and psychological symptoms and hemodynamics, and quantify differences in 180-day event-risk among observed profiles. Methods A secondary analysis of data collected during two prospective cohort studies by a single group of investigators was performed. Latent class mixture modeling was used to identify distinct symptom-hemodynamic profiles. Cox proportional hazards modeling was used to quantify difference in event-risk (HF emergency visit, hospitalization or death) among profiles. Results The mean age (n=291) was 57±13 years, 38% were female, and 61% had class III/IV HF. Three distinct symptom-hemodynamic profiles were identified. 17.9% of patients had concordant symptoms and hemodynamics (i.e. moderate physical and psychological symptoms matched the comparatively hemodynamic profile), 17.9% had severe symptoms and average hemodynamics, and 64.2% had poor hemodynamics and mild symptoms. Compared to those in the concordant profile, both profiles of symptom-hemodynamic mismatch were associated with a markedly increased event-risk (severe symptoms hazards ratio = 3.38, p=0.033; poor hemodynamics hazards ratio = 3.48, p=0.016). Conclusions A minority of adults with HF have concordant symptoms and hemodynamics. Either profile of symptom-hemodynamic mismatch in HF is associated with a greater risk of healthcare utilization for HF or death. PMID:24988323

  13. Stable particles

    International Nuclear Information System (INIS)

    Samios, N.P.

    1993-01-01

    I have been asked to review the subject of stable particles, essentially the particles that eventually comprised the meson and baryon octets. with a few more additions -- with an emphasis on the contributions made by experiments utilizing the bubble chamber technique. In this activity, much work had been done by the photographic emulsion technique and cloud chambers-exposed to cosmic rays as well as accelerator based beams. In fact, many if not most of the stable particles were found by these latter two techniques, however, the forte of the bubble chamber (coupled with the newer and more powerful accelerators) was to verify, and reinforce with large statistics, the existence of these states, to find some of the more difficult ones, mainly neutrals and further to elucidate their properties, i.e., spin, parity, lifetimes, decay parameters, etc

  14. 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. Th...

  15. Three-year hemodynamic performance, left ventricular mass regression, and prosthetic-patient mismatch after rapid deployment aortic valve replacement in 287 patients.

    Science.gov (United States)

    Haverich, Axel; Wahlers, Thorsten C; Borger, Michael A; Shrestha, Malakh; Kocher, Alfred A; Walther, Thomas; Roth, Matthias; Misfeld, Martin; Mohr, Friedrich W; Kempfert, Joerg; Dohmen, Pascal M; Schmitz, Christoph; Rahmanian, Parwis; Wiedemann, Dominik; Duhay, Francis G; Laufer, Günther

    2014-12-01

    Superior aortic valve hemodynamic performance can accelerate left ventricular mass regression and enhance survival and functional status after surgical aortic valve replacement. This can be achieved by rapid deployment aortic valve replacement using a subannular balloon-expandable stent frame, which functionally widens and reshapes the left ventricular outflow tract, to ensure a larger effective orifice area compared with conventional surgical valves. We report the intermediate-term follow-up data from a large series of patients enrolled in the Surgical Treatment of Aortic Stenosis With a Next Generation Surgical Aortic Valve (TRITON) trial. In a prospective, multicenter (6 European hospitals), single-arm study, 287 patients with aortic stenosis underwent rapid deployment aortic valve replacement using a stented trileaflet bovine pericardial bioprosthesis. Core laboratory echocardiography was performed at baseline, discharge, and 3 months, 1 year, and 3 years after rapid deployment aortic valve replacement. The mean patient age was 75.7 ± 6.7 years (range, 45-93; 49.1% women). The mean aortic valve gradient significantly decreased from discharge to 3 years of follow-up. The mean effective orifice area remained stable from discharge to 3 years. At 1 year, the left ventricular mass index had decreased by 14% (P replacement using a subannular balloon-expandable stent frame demonstrated excellent hemodynamic performance and significant left ventricular mass regression. With continued follow-up, future studies will establish whether these favorable structural changes correlate with improvement in long-term survival and functional status. Copyright © 2014 The American Association for Thoracic Surgery. Published by Elsevier Inc. All rights reserved.

  16. Relation of N-terminal pro-brain natriuretic peptide levels and their prognostic power in chronic stable heart failure to obesity status.

    Science.gov (United States)

    Frankenstein, Lutz; Remppis, Andrew; Nelles, Manfred; Schaelling, Bernd; Schellberg, Dieter; Katus, Hugo; Zugck, Christian

    2008-11-01

    To investigate the relationship between body mass index (BMI) and N-terminal pro-brain natriuretic peptide (NTproBNP) level and resultant prognostic capacity in chronic heart failure (CHF) controlled for known confounders. We formed 206 triplets of patients (n = 618) with stable systolic CHF matched with respect to age, sex, renal function (MDRD, modification of diet in renal disease formula), and NYHA class, each with a BMI >30 kg/m(2) (group 3), 20-24.9 kg/m(2) (group 1), and 25-29.9 kg/m(2) (group 2). BMI conveys a 4% drop in NTproBNP per unit increase. This influence remained significant after correction for age, sex, MDRD, NYHA, heart rate, rhythm, and ejection fraction. NTproBNP remained an independent predictor of adverse outcome after correction for age, sex, BMI, NYHA, MDRD, and ejection fraction. Despite numerical differences, prognostic power was comparable between BMI groups (log-transformed NTproBNP; group 1: hazard ratio (HR) 1.435, 95% CI 1.046-1.967, chi(2) 5.02, P = 0.03; group 2: HR 1.604, 95% CI 1.203-2.138, chi(2) 10.36, P = 0.001; group 3: HR 1.735, 95% CI 1.302-2.313, chi(2) 14.12, P = 0.0002) (P = NS, all). An NTproBNP correction factor was calculated. Even matched for NYHA, age, sex, and renal function, BMI exerts a significant and independent inverse influence on NTproBNP in patients with stable CHF. NTproBNP retained equal statistical power in all three BMI groups.

  17. Stable isotopes

    International Nuclear Information System (INIS)

    Brazier, J.L.; Guinamant, J.L.

    1995-01-01

    According to the progress which has been realised in the technology of separating and measuring isotopes, the stable isotopes are used as preferable 'labelling elements' for big number of applications. The isotopic composition of natural products shows significant variations as a result of different reasons like the climate, the seasons, or their geographic origins. So, it was proved that the same product has a different isotopic composition of alimentary and agriculture products. It is also important in detecting the pharmacological and medical chemicals. This review article deals with the technology, like chromatography and spectrophotometry, adapted to this aim, and some important applications. 17 refs. 6 figs

  18. Stable Tetraquarks

    Energy Technology Data Exchange (ETDEWEB)

    Quigg, Chris [Fermilab

    2018-04-13

    For very heavy quarks, relations derived from heavy-quark symmetry imply novel narrow doubly heavy tetraquark states containing two heavy quarks and two light antiquarks. We predict that double-beauty states will be stable against strong decays, whereas the double-charm states and mixed beauty+charm states will dissociate into pairs of heavy-light mesons. Observing a new double-beauty state through its weak decays would establish the existence of tetraquarks and illuminate the role of heavy color-antitriplet diquarks as hadron constituents.

  19. Venous hemodynamic changes in lower limb venous disease

    DEFF Research Database (Denmark)

    Lee, Byung Boong; Nicolaides, Andrew N; Myers, Kenneth

    2016-01-01

    ). Their aim was to confirm or dispel long-held hemodynamic principles and to provide a comprehensive review of venous hemodynamic concepts underlying the pathophysiology of lower limb venous disorders, their usefulness for investigating patients and the relevant hemodynamic changes associated with various...... forms of treatment. Chapter 1 is devoted to basic hemodynamic concepts and normal venous physiology. Chapter 2 presents the mechanism and magnitude of hemodynamic changes in acute deep vein thrombosis indicating their pathophysiological and clinical significance. Chapter 3 describes the hemodynamic...... changes that occur in different classes of chronic venous disease and their relation to the anatomic extent of disease in the macrocirculation and microcirculation. The next four chapters (Chapters 4-7) describe the hemodynamic changes resulting from treatment by compression using different materials...

  20. Stable beams

    CERN Multimedia

    2015-01-01

    Stable beams: two simple words that carry so much meaning at CERN. When LHC page one switched from "squeeze" to "stable beams" at 10.40 a.m. on Wednesday, 3 June, it triggered scenes of jubilation in control rooms around the CERN sites, as the LHC experiments started to record physics data for the first time in 27 months. This is what CERN is here for, and it’s great to be back in business after such a long period of preparation for the next stage in the LHC adventure.   I’ve said it before, but I’ll say it again. This was a great achievement, and testimony to the hard and dedicated work of so many people in the global CERN community. I could start to list the teams that have contributed, but that would be a mistake. Instead, I’d simply like to say that an achievement as impressive as running the LHC – a machine of superlatives in every respect – takes the combined effort and enthusiasm of everyone ...

  1. Central hemodynamic responses during serial exercise tests in heart failure patients using implantable hemodynamic monitors.

    Science.gov (United States)

    Ohlsson, A; Steinhaus, D; Kjellström, B; Ryden, L; Bennett, T

    2003-06-01

    Exercise testing is commonly used in patients with congestive heart failure for diagnostic and prognostic purposes. Such testing may be even more valuable if invasive hemodynamics are acquired. However, this will make the test more complex and expensive and only provides information from isolated moments. We studied serial exercise tests in heart failure patients with implanted hemodynamic monitors allowing recording of central hemodynamics. Twenty-one NYHA Class II-III heart failure patients underwent maximal exercise tests and submaximal bike or 6-min hall walk tests to quantify their hemodynamic responses and to study the feasibility of conducting exercise tests in patients with such devices. Patients were followed for 2-3 years with serial exercise tests. During maximal tests (n=70), heart rate increased by 52+/-19 bpm while S(v)O(2) decreased by 35+/-10% saturation units. RV systolic and diastolic pressure increased 29+/-11 and 11+/-6 mmHg, respectively, while pulmonary artery diastolic pressure increased 21+/-8 mmHg. Submaximal bike (n=196) and hall walk tests (n=172) resulted in S(v)O(2) changes of 80 and 91% of the maximal tests, while RV pressures ranged from 72 to 79% of maximal responses. An added potential value of implantable hemodynamic monitors in heart failure patients may be to quantitatively determine the true hemodynamic profile during standard non-invasive clinical exercise tests and to compare that to hemodynamic effects of regular exercise during daily living. It would be of interest to study whether such information could improve the ability to predict changes in a patient's clinical condition and to improve tailoring patient management.

  2. 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

  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. Hemodynamic monitoring in the critically ill.

    Science.gov (United States)

    Voga, G

    1995-06-01

    Monitoring of vital functions is one of the most important and essential tools in the management of critically ill patients in the ICU. Today it is possible to detect and analyze a great variety of physiological signals by various noninvasive and invasive techniques. An intensivist should be able to select and perform the most appropriate monitoring method for the individual patient considering risk-benefit ratio of the particular monitoring technique and the need for immediate therapy, specific diagnosis, continuous monitoring and evaluation of morphology should be included. Despite rapid development of noninvasive monitoring techniques, invasive hemodynamic monitoring in still one of the most basic ICU procedures. It enables monitoring of pressures, flow and saturation, pressures in the systemic and pulmonary circulation, estimation of cardiac performance and judgment of the adequacy of the cardiocirculatory system. Carefully and correctly obtained information are basis for proper hemodynamic assessment which usually effects the therapeutic decisions.

  5. 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

  6. Contribution of stable isotope to better understand breastfed infant nutritional status in burkina Faso: Longitudinal study with body composition measurement at one year

    International Nuclear Information System (INIS)

    Coulibaly, Nadine; Zeba, Augustin; Ouedraogo, Jean-Bosco; Somda, Serge Manituo

    2014-01-01

    Full text: Background and objectives: Exclusive breastfeeding for six months, followed by the introduction of appropriate complementary foods and continued breastfeeding, as recommended by the World Health Organization, are cornerstones in infant nutrition. In Burkina Faso, only limited information is available on the quantities of human milk consumed and the time of introduction of other foods into infants’ diets and the effect of feeding practice on the infant’s growth. In this work we analyzed infant’s nutritional status according to their feeding practice. Methods: We used the deuterium oxide (DO) dose-to-the mother technique to measure the human milk intake (HM) as well as the non-milk water intake (non-HM) by the babies at 3, 6, 9 and 12 mo. We also evaluated the infant body composition at 12 mo by giving a dose of DO to the babies in order to determine the fat-free mass (FFM) and the fat mass (FM). Saliva samples were collected from the babies and their mother and the DO enrichment in saliva was analyzed by FTIR. At each period, the anthropometric measurements were done to assess the infant nutritional status at 3,6, 9 and 12 mo according to the WHO standards. Results: The HM was maximum at 3 mo with a mean of 968.1 ml (95%CI = 847.2 ml-1089.1 ml), decreased at 6 mo to 918.4 ml (95%CI = 815.9 ml-1020.8 ml) that didn’t change until 12 mo. The non-HM that was 54.6 ml (95%CI = -12.6 ml-121.7 ml) increased significantly (p = 0.001) to 175.2 ml (95%CI = 100.2 ml-250.4 ml) at 6 mo. Exclusive breastfeeding was 32% at 3 mo and reduced to 16% at 6 mo. Breastfeeding was predominant after 6 mo and the contribution of HM in infant feeding was 80% at 9 mo and 69% at 12 mo. The anthropometric measurement showed that wasting was 1.5% at 3 mo but increase significantly (p = 0.04) to 8.7% at 6 mo. The DO dose to mother confirmed that all of the malnourished infants were not exclusive breastfed. At 9 mo the WHZ<-2 was reduced to 6.8%, but 4.5% of the children were

  7. The direct effect of incretin hormones on glucose and glycerol metabolism and hemodynamics

    DEFF Research Database (Denmark)

    Karstoft, Kristian; P. Mortensen, Stefan; H. Knudsen, Sine

    2015-01-01

    The objective of this study was to assess the insulin-independent effects of incretin hormones on glucose and glycerol metabolism and hemodynamics under eu- and hyperglycemic conditions. Young, healthy males (n=10) underwent three trials in a randomized, controlled, cross-over study. Each trial c...... hyperglycemia, GIP increases femoral artery blood flow with no effect on glucose metabolism, whereas GLP-1 increases glucose disposal, potentially, however, due to increased insulin levels....... consisted of a 2-stage (eu- and hyperglycemia) pancreatic clamp (using somatostatin to prevent endogenous insulin secretion). Glucose and lipid metabolism were measured via infusion of stable glucose and glycerol isotopic tracers. Hemodynamic variables (femoral, brachial and common carotid artery blood flow...... or glycerol kinetics were seen during euglycemia, whereas hyperglycemia resulted in increased GIR and glucose rate of disappearance (Rd) during GLP-1 compared to CON and GIP (Plevels, no differences between trials were seen for GIR or glucose Rd. Besides...

  8. 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...... stenosis. This is considered a result of chronic low perfusion pressure with subsequent loss of autoregulation, and autoregulatory control is first regained after some days.(ABSTRACT TRUNCATED AT 400 WORDS)...

  9. Stable or improved health status in the population 65 years and older in Stockholm, Sweden - an 8-year follow-up of self-reported health items.

    Science.gov (United States)

    Modig, Karin; Virtanen, Suvi; Ahlbom, Anders; Agahi, Neda

    2016-07-01

    Previous studies have reached different conclusions about whether health is improving in the ageing population. More studies with narrow age groups analyzed separately for men and women will contribute to the literature. To describe trends in self-reported indicators of health and health-related quality of life between 2002 and 2010, focusing on differences between gender and age groups. A population-based survey of individuals 65+ in the Stockholm County was used. Prevalence of health problems increased with age both among men and women. Men generally reported having no health problems to a larger extent than women, but the proportions reporting severe problems were similar. The larger picture is one of stability in health-related quality of life, even if several items developed for the better, especially among women. While the proportions reporting no health/functional problems increased for many items, the proportions reporting severe problems remained unchanged among men and improved only for two items among women. CONCLUSIONS OVERALL, IMPROVEMENTS WERE SEEN IN MANY OF THE HEALTH-RELATED QUALITY OF LIFE ITEMS AS WELL AS FOR SELF-RATED HEALTH AMONG WOMEN THE PROPORTIONS REPORTING LONG-TERM ILLNESS OR PERSISTENT HEALTH PROBLEMS INCREASED, BUT FEWER SEEM TO BE LIMITED IN THEIR DAILY ACTIVITIES BY THESE PROBLEMS THE STABLE PROPORTIONS OF POOR SELF-RATED HEALTH INDICATES THAT WHILE HEALTH AND FUNCTIONING SEEM TO BE IMPROVING FOR THE MAJORITY OF THE OLDER POPULATION, SOME GROUPS MAY BE LAGGING BEHIND FUTURE STUDIES SHOULD PAY ATTENTION TO CHANGES BOTH IN THE UPPER AND LOWER ENDS OF THE HEALTH SPECTRUM. © 2016 the Nordic Societies of Public Health.

  10. 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%. 

  11. Stable isotope and trace element status of subsistence-hunted bowhead and beluga whales in Alaska and gray whales in Chukotka

    Energy Technology Data Exchange (ETDEWEB)

    Dehn, Larissa-A. [Institute of Arctic Biology, University of Alaska Fairbanks, Fairbanks, AK 99775-7000 (United States)]. E-mail: ftld@uaf.edu; Follmann, Erich H. [Institute of Arctic Biology, University of Alaska Fairbanks, Fairbanks, AK 99775-7000 (United States); Rosa, Cheryl [Institute of Arctic Biology, University of Alaska Fairbanks, Fairbanks, AK 99775-7000 (United States); Duffy, Lawrence K. [Institute of Arctic Biology, University of Alaska Fairbanks, Fairbanks, AK 99775-7000 (United States); Thomas, Dana L. [Department of Mathematical Sciences, University of Alaska Fairbanks, Fairbanks, AK 99775-6660 (United States); Bratton, Gerald R. [Department of Veterinary Anatomy and Public Health, Texas A and M University, College Station, TX 77843 (United States); Taylor, Robert J. [Department of Veterinary Anatomy and Public Health, Texas A and M University, College Station, TX 77843 (United States); O' Hara, Todd M. [Institute of Arctic Biology, University of Alaska Fairbanks, Fairbanks, AK 99775-7000 (United States); Department of Wildlife Management, North Slope Borough, Barrow, AK 99725 (United States)

    2006-03-15

    Tissues of bowhead, beluga, and gray whales were analyzed for Ag, Cd, Cu, Se, Zn, THg and MeHg (belugas only). {delta}{sup 15}N and {delta}{sup 13}C in muscle were used to estimate trophic position and feeding habitat, respectively. Trace element concentrations in tissues were significantly different among whale species. Hepatic Ag was higher in belugas than bowheads and gray whales. Gray whales had lower Cd concentrations in liver and kidney than bowhead and belugas and a sigmoid correlation of Cd with length was noted for all whales. Renal and hepatic Se and THg were higher in belugas than in baleen whales. The hepatic molar ratio of Se:THg exceeded 1:1 in all species and was negatively correlated to body length. Hepatic and renal Zn in subsistence-harvested gray whales was lower than concentrations for stranded whales. Se:THg molar ratios and tissue concentrations of Zn may show promise as potential indicators of immune status and animal health.

  12. Stable isotope and trace element status of subsistence-hunted bowhead and beluga whales in Alaska and gray whales in Chukotka

    International Nuclear Information System (INIS)

    Dehn, Larissa-A.; Follmann, Erich H.; Rosa, Cheryl; Duffy, Lawrence K.; Thomas, Dana L.; Bratton, Gerald R.; Taylor, Robert J.; O'Hara, Todd M.

    2006-01-01

    Tissues of bowhead, beluga, and gray whales were analyzed for Ag, Cd, Cu, Se, Zn, THg and MeHg (belugas only). δ 15 N and δ 13 C in muscle were used to estimate trophic position and feeding habitat, respectively. Trace element concentrations in tissues were significantly different among whale species. Hepatic Ag was higher in belugas than bowheads and gray whales. Gray whales had lower Cd concentrations in liver and kidney than bowhead and belugas and a sigmoid correlation of Cd with length was noted for all whales. Renal and hepatic Se and THg were higher in belugas than in baleen whales. The hepatic molar ratio of Se:THg exceeded 1:1 in all species and was negatively correlated to body length. Hepatic and renal Zn in subsistence-harvested gray whales was lower than concentrations for stranded whales. Se:THg molar ratios and tissue concentrations of Zn may show promise as potential indicators of immune status and animal health

  13. Prognostic value of noninvasive hemodynamic evaluation of the acute effect of levosimendan in advanced heart failure.

    Science.gov (United States)

    Malfatto, Gabriella; Della Rosa, Francesco; Rella, Valeria; Villani, Alessandra; Branzi, Giovanna; Blengino, Simonetta; Giglio, Alessia; Facchini, Mario; Parati, Gianfranco

    2014-04-01

    Optimization of inotropic treatment in worsening heart failure sometimes requires invasive hemodynamic assessment in selected patients. Impedance cardiography (ICG) may be useful for a noninvasive hemodynamic evaluation. ICG was performed in 40 patients (69 ± 8 years; left ventricular ejection fraction 27.5 ± 5.6%; New York Heart Association 3.18 ± 0.34; Interagency Registry for Mechanically Assisted Circulatory Support 5.48 ± 0.96, before and after infusion of Levosimendan (0.1–0.2 µg/kg per min for up to 24 h). Echocardiogram, ICG [measuring cardiac index (CI), total peripheral resistances (TPRs) and thoracic fluid content (TFC)] and plasma levels of brain natriuretic peptide (BNP) were obtained; in nine patients, right heart catheterization was also carried out. When right catheterization and ICG were performed simultaneously, a significant relationship was observed between values of CI and TPR, and between TFC and pulmonary wedge pressure. ICG detected the Levosimendan-induced recovery of the hemodynamic status, associated with improved systolic and diastolic function and reduction in BNP levels. One-year mortality was 4.4%. At multivariate analysis, independent predictors of mortality were: no improvement in the severity of mitral regurgitation, a persistent restrictive filling pattern (E/E’ > 15), a reduction of BNP levels below 30% and a change below 10% in CI, TPR and TFC. When combined, absence of hemodynamic improvement at ICG could predict 1-year mortality with better sensitivity (86%) and specificity (85%) than the combination of echocardiographic and BNP criteria only (sensitivity 80% and specificity 36%). Noninvasive hemodynamic evaluation of heart failure patients during infusion of inodilator drugs is reliable and may help in their prognostic stratification.

  14. Role and Effectiveness of Percutaneous Arterial Embolization in Hemodynamically Unstable Patients with Ruptured Splanchnic Artery Pseudoaneurysms

    International Nuclear Information System (INIS)

    Dohan, Anthony; Eveno, Clarisse; Dautry, Raphael; Guerrache, Youcef; Camus, Marine; Boudiaf, Mourad; Gayat, Etienne; Dref, Olivier Le; Sirol, Marc; Soyer, Philippe

    2015-01-01

    PurposeTo assess the role and effectiveness of percutaneous arterial embolization (TAE) in patients with hemodynamic instability due to hypovolemic shock secondary to ruptured splanchnic artery pseudoaneurysms (SAPA).Materials and MethodsSeventeen patients (11 men, 6 women; mean age, 53 years) with hemodynamic instability (systolic blood pressure <90 mmHg) due to hypovolemic shock secondary to ruptured SAPA were treated by TAE. Clinical files, multidetector row computed tomography angiography, and angiographic examinations along with procedure details were reviewed.ResultsSeventeen SAPAs were present, predominantly located on gastroduodenal or pancreatic arteries (9/17; 53 %). Angiography showed extravasation of contrast medium from SAPA in 15/17 patients (88 %). Technical success rate of TAE was 100 %. TAE was performed using metallic coils in all patients (100 %), in association with gelatin sponge in 5/17 patients (29 %). TAE allowed controlling the bleeding and returning to normal hemodynamic status in 16/17 patients (94 %). In 1/17 patient (6 %), surgery was needed to definitively control the bleeding. The mortality and morbidity rate of TAE at 30 days were 0 and 12 %, respectively. Morbidity consisted in coil migration in 1/17 patient (6 %) and transient serum liver enzyme elevation in 1/17 patient (6 %).ConclusionTAE is an effective and safe treatment option for ruptured SAPA in hemodynamically unstable patients, with a success rate of 94 %. Our results suggest that TAE should be the favored option in patients with hemodynamic instability due to ruptured SAPA

  15. Role and Effectiveness of Percutaneous Arterial Embolization in Hemodynamically Unstable Patients with Ruptured Splanchnic Artery Pseudoaneurysms

    Energy Technology Data Exchange (ETDEWEB)

    Dohan, Anthony, E-mail: anthony.dohan@lrb.aphp.fr [Hôpital Lariboisière, Assistance Publique-Hôpitaux de Paris, Department of Abdominal and Interventional Imaging (France); Eveno, Clarisse, E-mail: clarisse.eveno@lrb.aphp.fr [Université Paris-Diderot, Sorbonne Paris Cité (France); Dautry, Raphael, E-mail: raphael.dautry@lrb.aphp.fr; Guerrache, Youcef, E-mail: docyoucef05@yahoo.fr [Hôpital Lariboisière, Assistance Publique-Hôpitaux de Paris, Department of Abdominal and Interventional Imaging (France); Camus, Marine, E-mail: marine.camus@lrb.aphp.fr [Université Paris-Diderot, Sorbonne Paris Cité (France); Boudiaf, Mourad, E-mail: mourad.boudiaf@lrb.aphp.fr [Hôpital Lariboisière, Assistance Publique-Hôpitaux de Paris, Department of Abdominal and Interventional Imaging (France); Gayat, Etienne, E-mail: etienne.gayat@lrb.aphp.fr [Université Paris-Diderot, Sorbonne Paris Cité (France); Dref, Olivier Le, E-mail: olivier.ledref@lrb.aphp.fr; Sirol, Marc, E-mail: marc.sirol@lrb.aphp.fr; Soyer, Philippe, E-mail: philippe.soyer@lrb.aphp.fr [Hôpital Lariboisière, Assistance Publique-Hôpitaux de Paris, Department of Abdominal and Interventional Imaging (France)

    2015-08-15

    PurposeTo assess the role and effectiveness of percutaneous arterial embolization (TAE) in patients with hemodynamic instability due to hypovolemic shock secondary to ruptured splanchnic artery pseudoaneurysms (SAPA).Materials and MethodsSeventeen patients (11 men, 6 women; mean age, 53 years) with hemodynamic instability (systolic blood pressure <90 mmHg) due to hypovolemic shock secondary to ruptured SAPA were treated by TAE. Clinical files, multidetector row computed tomography angiography, and angiographic examinations along with procedure details were reviewed.ResultsSeventeen SAPAs were present, predominantly located on gastroduodenal or pancreatic arteries (9/17; 53 %). Angiography showed extravasation of contrast medium from SAPA in 15/17 patients (88 %). Technical success rate of TAE was 100 %. TAE was performed using metallic coils in all patients (100 %), in association with gelatin sponge in 5/17 patients (29 %). TAE allowed controlling the bleeding and returning to normal hemodynamic status in 16/17 patients (94 %). In 1/17 patient (6 %), surgery was needed to definitively control the bleeding. The mortality and morbidity rate of TAE at 30 days were 0 and 12 %, respectively. Morbidity consisted in coil migration in 1/17 patient (6 %) and transient serum liver enzyme elevation in 1/17 patient (6 %).ConclusionTAE is an effective and safe treatment option for ruptured SAPA in hemodynamically unstable patients, with a success rate of 94 %. Our results suggest that TAE should be the favored option in patients with hemodynamic instability due to ruptured SAPA.

  16. The relationship between Plasmodium infection, anaemia and nutritional status in asymptomatic children aged under five years living in stable transmission zones in Kinshasa, Democratic Republic of Congo.

    Science.gov (United States)

    Maketa, Vivi; Mavoko, Hypolite Muhindo; da Luz, Raquel Inocêncio; Zanga, Josué; Lubiba, Joachim; Kalonji, Albert; Lutumba, Pascal; Van Geertruyden, Jean-Pierre

    2015-02-18

    Malaria is preventable and treatable when recommended interventions are properly implemented. Thus, diagnosis and treatment focus on symptomatic individuals while asymptomatic Plasmodium infection (PI) plays a role in the sustainability of the transmission and may also have an impact on the morbidity of the disease in terms of anaemia, nutritional status and even cognitive development of children. The objective of this study was to assess PI prevalence and its relationship with known morbidity factors in a vulnerable but asymptomatic stratum of the population. A simple random sample, household survey in asymptomatic children under the age of five was conducted from April to September 2012 in two health areas of the health zone of Mont Ngafula 1, Kinshasa, Democratic Republic of Congo. The PI prevalence were 30.9% (95% CI: 26.5-35.9) and 14.3% (95% CI: 10.5-18.1) in Cité Pumbu and Kindele health areas, respectively, (OR: 2.7; p <0.001). All were Plasmodium falciparum infected and 4% were co-infected with Plasmodium malariae. In Cité Pumbu and Kindele, the prevalence of anaemia (haemoglobin <11 g/dL) was 61.6% (95% CI: 56.6-66.5) and 39.3% (95% CI: 34.0-44.6), respectively, (OR: 2.5; p <0.001). The health area of Cité Pumbu had 32% (95% CI: 27.5-37.0) of chronic malnutrition (HAZ score ≤ -2SD) compared to 5.1% (95% CI: 2.8-7.6) in Kindele. PI was predictor factor for anaemia (aOR: 3.5, p =0.01) and within infected children, there was an inverse relationship between parasite density and haemoglobin level (β = -5*10(-5), p <0.001). Age older than 12 months (aOR: 3.8, p = 0.01), presence of anaemia (aOR: 3.4, p =0.001), chronic malnutrition (aOR: 1.8, p = 0.01), having a single parent/guardian (aOR: 1.6, p =0.04), and the non-use of insecticide-treated nets (aOR: 1.7, p = 0.04) were all predictors for PI in the overall population. PI in asymptomatic children was correlated with anaemia and chronic malnutrition and was thus a harmful condition in the study

  17. 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

  18. The Effects of a Multiflavonoid Supplement on Vascular and Hemodynamic Parameters following Acute Exercise

    Directory of Open Access Journals (Sweden)

    Rebecca M. Kappus

    2011-01-01

    Full Text Available Antioxidants can decrease oxidative stress and combined with acute exercise they may lead to further decreases in blood pressure. The purpose of this study was to investigate the effects of 2 weeks of antioxidant supplementation on vascular distensibility and cardiovascular hemodynamics during postexercise hypotension. Methods. Twenty young subjects were randomized to placebo (=10 or antioxidant supplementation (=10 for two weeks. Antioxidant status, vascular distensibility, and hemodynamics were obtained before, immediately, and 30 minutes after an acute bout of aerobic exercise both before and after supplementation. Results. Two weeks of antioxidant supplementation resulted in a greater systolic blood pressure (SBP decrease during postexercise hypotension (PEH and significant decreases in augmentation index versus placebo (12.5% versus 3.5%, resp.. Also ferric-reducing ability of plasma (FRAP increased significantly (interaction P = 0.024 after supplementation. Conclusion. Supplementation showed an additive effect on PEH associated with increased FRAP values and decreases in systolic blood pressure and augmentation index.

  19. The effects of a multiflavonoid supplement on vascular and hemodynamic parameters following acute exercise.

    Science.gov (United States)

    Kappus, Rebecca M; Curry, Chelsea D; McAnulty, Steve; Welsh, Janice; Morris, David; Nieman, David C; Soukup, Jeffrey; Collier, Scott R

    2011-01-01

    Antioxidants can decrease oxidative stress and combined with acute exercise they may lead to further decreases in blood pressure. The purpose of this study was to investigate the effects of 2 weeks of antioxidant supplementation on vascular distensibility and cardiovascular hemodynamics during postexercise hypotension. Twenty young subjects were randomized to placebo (n = 10) or antioxidant supplementation (n = 10) for two weeks. Antioxidant status, vascular distensibility, and hemodynamics were obtained before, immediately, and 30 minutes after an acute bout of aerobic exercise both before and after supplementation. Two weeks of antioxidant supplementation resulted in a greater systolic blood pressure (SBP) decrease during postexercise hypotension (PEH) and significant decreases in augmentation index versus placebo (12.5% versus 3.5%, resp.). Also ferric-reducing ability of plasma (FRAP) increased significantly (interaction P = 0.024) after supplementation. Supplementation showed an additive effect on PEH associated with increased FRAP values and decreases in systolic blood pressure and augmentation index.

  20. Central and peripheral hemodynamics in exercising humans

    DEFF Research Database (Denmark)

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

    2015-01-01

    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...... 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....

  1. Pain and hemodynamic effects in aortofemoral angiography

    International Nuclear Information System (INIS)

    Nyman, U.; Nilsson, P.; Westergren, A.

    1982-01-01

    Two new contrast media, iohexol (non-ionic monomer) and ioxaglate (monoacidic dimer), were compared with the non-ionic metrizamide during aortofemoral angiography in a single blind randomized trial in 2 groups of patients with 20 in each. The degree of heat and pain produced by iohexol and ioxaglate did not differ significantly from that produced by metrizamide, while subsequent injections of metrizoate caused significantly more heat and pain. The hemodynamic effects recorded in 10 patients in each group showed that iohexol and ioxaglate induced a decrease in vascular resistance, decrease in blood pressure and increase in heart rate not differing significantly from that induced by metrizamide. (Auth.)

  2. Effect of hemodynamics on outcome of subtotally occluded paraclinoid aneurysms after stent-assisted coil embolization.

    Science.gov (United States)

    Liu, Jian; Jing, Linkai; Wang, Chao; Paliwal, Nikhil; Wang, Shengzhang; Zhang, Ying; Xiang, Jianping; Siddiqui, Adnan H; Meng, Hui; Yang, Xinjian

    2016-11-01

    Endovascular treatment of paraclinoid aneurysms is preferred in clinical practice. Flow alterations caused by stents and coils may affect treatment outcome. To assess hemodynamic changes following stent-assisted coil embolization (SACE) in subtotally embolized paraclinoid aneurysms with residual necks that were predisposed to recanalization. We studied 27 paraclinoid aneurysms (seven recanalized and 20 stable) treated with coils and Enterprise stents. Computational fluid dynamic simulations were performed on patient-specific aneurysm geometries using virtual stenting and porous media technology. After stent placement in 27 cases, aneurysm flow velocity decreased significantly, the reduction gradually increasing from the neck plane (11.9%), to the residual neck (12.3%), to the aneurysm dome (16.3%). Subsequent coil embolization was performed after stent placement and the hemodynamic factors decreased further and significantly at all aneurysm regions except the neck plane. In a comparison of recanalized and stable cases, univariate analysis showed no significant differences in any parameter before treatment. After stent-assisted coiling, only the reduction in area-averaged velocity at the neck plane differed significantly between recanalized (8.1%) and stable cases (20.5%) (p=0.016). Aneurysm flow velocity can be significantly decreased by stent placement and coil embolization. However, hemodynamics at the aneurysm neck plane is less sensitive to coils. Significant reduction in flow velocity at the neck plane may be an important factor in preventing recanalization of paraclinoid aneurysms after subtotal SACE. 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/.

  3. 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.

  4. 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.).

  5. 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.)

  6. 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.

  7. 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.

  8. 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....

  9. Development of BOLD signal hemodynamic responses in the human brain

    NARCIS (Netherlands)

    Arichi, T.; Varela, M.; Melendez-Calderon, A.; Allievi, A.; Merchant, N.; Tusor, N.; Counsell, S.J.; Burdet, E.; Beckmann, Christian; Edwards, A.D.

    2012-01-01

    In the rodent brain the hemodynamic response to a brief external stimulus changes significantly during development. Analogous changes in human infants would complicate the determination and use of the hemodynamic response function (HRF) for functional magnetic resonance imaging (fMRI) in developing

  10. 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...

  11. Severe carotid stenosis and impaired cerebral hemodynamics can influence cognitive deterioration.

    Science.gov (United States)

    Balestrini, Simona; Perozzi, Cecilia; Altamura, Claudia; Vernieri, Fabrizio; Luzzi, Simona; Bartolini, Marco; Provinciali, Leandro; Silvestrini, Mauro

    2013-06-04

    To evaluate whether severe carotid stenosis and related hemodynamics impairment may increase the risk of cognitive deterioration in asymptomatic subjects. A total of 210 subjects with unilateral asymptomatic severe carotid stenosis and 109 healthy controls were included and prospectively evaluated for a 36-month period. At entry, demographics, vascular risk profile, and pharmacologic treatments were defined. Cerebral hemodynamics was assessed by transcranial Doppler-based breath-holding index (BHI) test. Cognitive status was evaluated with the Mini-Mental State Examination (MMSE) at entry and at the end of the follow-up period. Cognitive deterioration was defined as a decrease in the MMSE score of 3 points or more during the overall follow-up period. Subjects with carotid stenosis showed an increased probability of developing cognitive deterioration compared with the group without stenosis (odds ratio [OR] 4.16 [95% confidence interval (CI) 1.89-9.11]; p < 0.001). The presence of an impaired BHI ipsilateral to the stenosis was associated with an increased incidence of reduction in cognitive performance (OR 14.66 [95% CI 7.51-28.59]; p < 0.001). Our findings show that the presence of a severe carotid stenosis influences cognitive deterioration over a 36-month period in asymptomatic subjects. An associated hemodynamic impairment significantly increases the risk. Evaluation of functional consequences of carotid stenosis may offer the opportunity to select a group with an increased risk of developing cognitive impairment from subjects with asymptomatic severe carotid stenosis.

  12. Collateral circulation alters downstream hemodynamic stress caused by intracranial atherosclerotic stenosis.

    Science.gov (United States)

    Liu, Xin; Dornbos, David; Pu, Yuehua; Leng, Xinyi; Song, Ligang; Jia, Baixue; Pan, Yuesong; Wang, David; Miao, Zhongrong; Wang, Yilong; Liu, Liping; Wang, Yongjun

    2017-06-01

    Fractional flow reserve (FFR) accurately predicts the degree of stenosis and is now widely used to identify clinically significant severe coronary artery lesions. In the current study, we utilized a similar indicator, fractional flow (FF), to determine the hemodynamic impact of symptomatic intracranial atherosclerotic stenosis (ICAS) and to assess the correlation of FF with the severity of stenosis and collateral circulation. Patients with symptomatic ICAS (70-99% stenosis) confirmed on digital subtraction angiography (DSA) were consecutively recruited. FF was obtained during DSA examination with the use of pressure sensors and was measured as a ratio, comparing measurements distal to an ICAS lesion (Pd) and within the aorta (Pa). The degree of leptomeningeal collateralization was graded from zero (absent) to four (complete compensatory). The correlation between FF, anatomical stenosis, and collateral status was then analyzed. Twenty-five patients with a mean age of 55.6 years were analyzed. The median percentage of stenosis and median FF were 82.3 and 0.68%, respectively. Eleven patients were found to have poor collateralization (grade 0-2), and fourteen patients were identified with good collateral circulation (grade 3-4). Overall, the hemodynamic impact of an atherosclerotic lesions worsened (decreased FF) as the percentage of stenosis increased, although this did not reach statistical significance (r = -0.398, p = 0.06). However, the status of collateralization significantly altered this correlation, worsening the hemodynamic impact in patients with poor collateral circulation (r = -0.677, p = 0.032). There was no difference in patients with good collateral circulation (r = -0.279, p = 0.356). An anatomically severe (70-99%) symptomatic ICAS lesion may generate significant hemodynamic stress downstream as assessed by the indicator FF, particularly in patients with poor collateral circulation. Further, good collateralization may mitigate this

  13. [Myocardial contractility and hemodynamics in hypothyroidism].

    Science.gov (United States)

    Selivonenko, V G

    1977-01-01

    The author determined the phasic structure of the systole of the left ventricle by the method of polycardiography and hemodynamics in 20 patients suffering from hypothyrodism. Blood plasma and erythrocyte electrolytes were examined at the same time. Patients with hypothyroidism displayed a phasic syndrome of hypodynamia and a marked correlation between the phase of the synchronous contraction, the period of ejection, the strength of contraction of the left ventricle and the electrolyte content. Sodium and magnesium produced the greatest influence on the phasic structure of the systole; potassium and calcium had a lesser effect. The heart stroke volume diminished; as to the cardiac index, expenditure of the energy of cardiac contractions directed to the maintenance of movement of 1 litre of the minute blood volume; the external work, and the peripheral vascular resistance displayed no significant change.

  14. Hemodynamic stress testing using pacing tachycardia

    International Nuclear Information System (INIS)

    McKay, R.G.; Grossman, W.

    1986-01-01

    A trial pacing was first introduced in 1967 by Sowton and co-workers as a stress test which could be used in the cardiac catheterization laboratory to evaluate patients with schemic heart disease. Sowton noted that artificially increasing the heart rate by pacing the right atrium could usually induce angina in patients with symptomatic coronary artery disease. Since Sowton's original description, numerous investigators have described characteristic pacing-induced electrocardiographic changes, derangements of myocardial lactate metabolism, hemodynamic abnormalities, regional wall abnormalities, and defects in thallium scintigraphy. Although agreement on the overall usefulness of atrial pacing has not been uniform, it is clear that the technique can safely and reliably induce ischemia in most patients with coronary artery disease and that information obtained during the pacing-induced ischemic state can often be helpful in the diagnosis and treatment of the patient's underlying disease

  15. 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)

  16. Hemodynamic effects of sodium bicarbonate administration.

    Science.gov (United States)

    Katheria, A C; Brown, M K; Hassan, K; Poeltler, D M; Patel, D A; Brown, V K; Sauberan, J B

    2017-05-01

    To describe the hemodynamic changes that occur with sodium bicarbonate (NaHCO 3 ) administration in premature neonates. This retrospective study included premature neonates 23 to 31+6 weeks of gestational age who underwent continuous cardiac and cerebral monitoring as participants in prospective trials at our institution, and who received NaHCO 3 infused over 30 min in the first 24 h of life. Blood pressure (BP), heart rate, cardiac output (CO), SpO 2 and cerebral oximetry (StO 2 ) were captured every 2 s. A baseline was established for all continuous data and averaged over the 10 min before NaHCO 3 administration. Baseline was compared with measurements over 10 min epochs until 80 min after administration. Arterial blood gases before and within 1 h of administration were also compared. Significance was set at P<0.05. A total of 36 subjects received NaHCO 3 (1.3±0.3 mEq kg -1 ) in the first 24 h (14±8.5 h) of life. NaHCO 3 administration increased pH (7.23 vs 7.28, P<0.01) and decreased base deficit (-8.9 vs -6.8, P<0.01) and PaCO 2 (45 vs 43 mm Hg, P<0.05). There was a transient but significant (P<0.05) decrease in systemic BP coinciding with an increase in cerebral oxygenation without an increase in oxygen extraction. CO did not change. Early postnatal NaHCO 3 administration does not acutely improve CO but does cause transient fluctuations in cerebral and cardiovascular hemodynamics in extremely premature infants.

  17. 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)

  18. Congenital heart malformations induced by hemodynamic altering surgical interventions

    Directory of Open Access Journals (Sweden)

    Madeline eMidgett

    2014-08-01

    Full Text Available Embryonic heart formation results from a dynamic interplay between genetic and environmental factors. Blood flow during early embryonic stages plays a critical role in heart development, as interactions between flow and cardiac tissues generate biomechanical forces that modulate cardiac growth and remodeling. Normal hemodynamic conditions are essential for proper cardiac development, while altered blood flow induced by surgical manipulations in animal models result in heart defects similar to those seen in humans with congenital heart disease. This review compares the altered hemodynamics, changes in tissue properties, and cardiac defects reported after common surgical interventions that alter hemodynamics in the early chick embryo, and shows that interventions produce a wide spectrum of cardiac defects. Vitelline vein ligation and left atrial ligation decrease blood pressure and flow; and outflow tract banding increases blood pressure and flow velocities. These three surgical interventions result in many of the same cardiac defects, which indicate that the altered hemodynamics interfere with common looping, septation and valve formation processes that occur after intervention and that shape the four-chambered heart. While many similar defects develop after the interventions, the varying degrees of hemodynamic load alteration among the three interventions also result in varying incidence and severity of cardiac defects, indicating that the hemodynamic modulation of cardiac developmental processes is strongly dependent on hemodynamic load.

  19. Hemodynamic Perturbations in Deep Brain Stimulation Surgery: First Detailed Description

    Directory of Open Access Journals (Sweden)

    Tumul Chowdhury

    2017-08-01

    Full Text Available Background: Hemodynamic perturbations can be anticipated in deep brain stimulation (DBS surgery and may be attributed to multiple factors. Acute changes in hemodynamics may produce rare but severe complications such as intracranial bleeding, transient ischemic stroke and myocardium infarction. Therefore, this retrospective study attempts to determine the incidence of hemodynamic perturbances (rate and related risk factors in patients undergoing DBS surgery.Materials and Methods: After institutional approval, all patients undergoing DBS surgery for the past 10 years were recruited for this study. Demographic characteristics, procedural characteristics and intraoperative hemodynamic changes were noted. Event rate was calculated and the effect of all the variables on hemodynamic perturbations was analyzed by regression model.Results: Total hemodynamic adverse events during DBS surgery was 10.8 (0–42 and treated in 57% of cases.Conclusion: Among all the perioperative variables, the baseline blood pressure including systolic, diastolic, and mean arterial pressure was found to have highly significant effect on these intraoperative hemodynamic perturbations.

  20. Stable Isotope Data

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Tissue samples (skin, bone, blood, muscle) are analyzed for stable carbon, stable nitrogen, and stable sulfur analysis. Many samples are used in their entirety for...

  1. 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

  2. Levosimendan reduces plasma B-type natriuretic peptide and interleukin 6, and improves central hemodynamics in severe heart failure patients.

    Science.gov (United States)

    Kyrzopoulos, Stamos; Adamopoulos, Stamatis; Parissis, John T; Rassias, John; Kostakis, George; Iliodromitis, Efstathios; Degiannis, Dimitrios; Kremastinos, Dimitrios Th

    2005-03-30

    Plasma B-type natriuretic peptide (BNP) and interleukin 6 (IL-6) levels have recently been demonstrated as significant neurohormonal markers associated with the progression of chronic heart failure (CHF). Additionally, clinical studies have shown that the calcium sensitizer, levosimendan, beneficially affects the central hemodynamics of CHF patients and improves their long-term prognosis. This study investigates whether levosimendan-induced hemodynamic improvement of CHF patients is related to the respective changes of NT-proBNP and IL-6 levels. Circulating levels of NT-pro BNP and IL-6 were measured by enzyme-linked immunosorbent assay (ELISA) in 12 patients with decompensated advanced CHF at baseline, immediately after the end of a 24-h levosimendan infusion and 72 h after the initiation of treatment. Hemodynamic parameters of patients (pulmonary wedge and pulmonary artery pressure (PAP), systemic and pulmonary vascular resistance (PVR), stroke volume, and cardiac output and index) were also monitored during the same period. NT-proBNP and IL-6 levels were significantly reduced in severe CHF patients within 72 h after the initiation of levosimendan treatment (pNT-proBNP levels and the respective reduction of pulmonary wedge pressure (r(s)=0.65, pBNP and IL-6 levels may be useful biochemical markers related with the levosimendan-induced improvement in central hemodynamics and the clinical status of decompensated advanced CHF patients.

  3. Echocardiographic Evaluation of Hemodynamic Changes in Left-Sided Heart Valves in Pregnant Women With Valvular Heart Disease.

    Science.gov (United States)

    Samiei, Niloufar; Amirsardari, Mandana; Rezaei, Yousef; Parsaee, Mozhgan; Kashfi, Fahimeh; Hantoosh Zadeh, Sedigheh; Beikmohamadi, Somayeh; Fouladi, Masoumeh; Hosseini, Saeid; Peighambari, Mohammad Mehdi; Mohebbi, Ahmad

    2016-10-01

    Physiologic changes during pregnancy can deteriorate or improve patients' hemodynamic status in the setting of valvular heart disease. There are sparse data regarding the effect of pregnancy on valve hemodynamics in normal pregnant women with known valvular heart disease. In a prospective study from July 2014 to January 2016, a total of 52 normal pregnant women who had mitral stenosis, aortic stenosis, or a history of mitral valve or aortic valve replacements were assessed. All patients underwent echocardiographic examinations and hemodynamic parameters were measured for both the mitral valve and aortic valve at first, second, and third trimesters. The parameters included mean gradient, peak gradient, mean gradient/heart rate, peak gradient/heart rate, pressure halftime, dimensionless velocity index, and valve area. Although most hemodynamic parameters (i.e., mean gradient, peak gradient, mean gradient/heart rate, and peak gradient/heart rate) increased approximately 50% from first to second trimester and first to third trimester (p 0.05). The ratio of changes between trimesters for valve area and dimensionless velocity index were comparable. No clinical decompensations were observed except for 3 and 7 cases of deterioration to functional class II at second and third trimesters, respectively. In conclusion, during a full-term and uncomplicated pregnancy, mitral and aortic valve gradients increase without significant changes in valve area that are more marked between the second and first trimester than between the third and second trimester. Copyright © 2016 Elsevier Inc. All rights reserved.

  4. 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

  5. Levosimendan for Hemodynamic Support after Cardiac Surgery.

    Science.gov (United States)

    Landoni, Giovanni; Lomivorotov, Vladimir V; Alvaro, Gabriele; Lobreglio, Rosetta; Pisano, Antonio; Guarracino, Fabio; Calabrò, Maria G; Grigoryev, Evgeny V; Likhvantsev, Valery V; Salgado-Filho, Marcello F; Bianchi, Alessandro; Pasyuga, Vadim V; Baiocchi, Massimo; Pappalardo, Federico; Monaco, Fabrizio; Boboshko, Vladimir A; Abubakirov, Marat N; Amantea, Bruno; Lembo, Rosalba; Brazzi, Luca; Verniero, Luigi; Bertini, Pietro; Scandroglio, Anna M; Bove, Tiziana; Belletti, Alessandro; Michienzi, Maria G; Shukevich, Dmitriy L; Zabelina, Tatiana S; Bellomo, Rinaldo; Zangrillo, Alberto

    2017-05-25

    Acute left ventricular dysfunction is a major complication of cardiac surgery and is associated with increased mortality. Meta-analyses of small trials suggest that levosimendan may result in a higher rate of survival among patients undergoing cardiac surgery. We conducted a multicenter, randomized, double-blind, placebo-controlled trial involving patients in whom perioperative hemodynamic support was indicated after cardiac surgery, according to prespecified criteria. Patients were randomly assigned to receive levosimendan (in a continuous infusion at a dose of 0.025 to 0.2 μg per kilogram of body weight per minute) or placebo, for up to 48 hours or until discharge from the intensive care unit (ICU), in addition to standard care. The primary outcome was 30-day mortality. The trial was stopped for futility after 506 patients were enrolled. A total of 248 patients were assigned to receive levosimendan and 258 to receive placebo. There was no significant difference in 30-day mortality between the levosimendan group and the placebo group (32 patients [12.9%] and 33 patients [12.8%], respectively; absolute risk difference, 0.1 percentage points; 95% confidence interval [CI], -5.7 to 5.9; P=0.97). There were no significant differences between the levosimendan group and the placebo group in the durations of mechanical ventilation (median, 19 hours and 21 hours, respectively; median difference, -2 hours; 95% CI, -5 to 1; P=0.48), ICU stay (median, 72 hours and 84 hours, respectively; median difference, -12 hours; 95% CI, -21 to 2; P=0.09), and hospital stay (median, 14 days and 14 days, respectively; median difference, 0 days; 95% CI, -1 to 2; P=0.39). There was no significant difference between the levosimendan group and the placebo group in rates of hypotension or cardiac arrhythmias. In patients who required perioperative hemodynamic support after cardiac surgery, low-dose levosimendan in addition to standard care did not result in lower 30-day mortality than placebo

  6. The hemodynamic repercussions of the autonomic modulations in ...

    African Journals Online (AJOL)

    Igor Victorovich Lakhno

    2017-01-16

    Jan 16, 2017 ... autonomic balance, arterial and venous hemodynamic Doppler indices and CTG variables in case of nor- mal fetal ... score of decelerations. Results: The .... puter electrocardiographic system ''Cardiolab Baby Card” (Scien-.

  7. Hemodynamic changes after levothyroxine treatment in subclinical hypothyroidism

    DEFF Research Database (Denmark)

    Faber, J; Petersen, L; Wiinberg, N

    2002-01-01

    by LT(4) (p treatment in SH results in changes in hemodynamic parameters of potentially beneficial character. SH and overt hypothyroidism should......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......) and T(3) estimates) LT(4) treatment resulted in 6% reduction in supine MAP (p treatment (p

  8. Reliability of oscillometric central hemodynamic responses to an orthostatic challenge

    OpenAIRE

    Stoner, Lee; Bonner, Chantel; Credeur, Daniel; Lambrick, Danielle; Faulkner, James; Wadsworth, Daniel; Williams, Michelle A.

    2015-01-01

    BackgroundMonitoring central hemodynamic responses to an orthostatic challenge may provide important insight into autonomic nervous system function. Oscillometric pulse wave analysis devices have recently emerged, presenting clinically viable options for investigating central hemodynamic properties. The purpose of the current study was to determine whether oscillometric pulse wave analysis can be used to reliably (between-day) assess central blood pressure and central pressure augmentation (a...

  9. Postural hemodynamic changes after turning to prone position

    Directory of Open Access Journals (Sweden)

    Микола Віталійович Лизогуб

    2015-03-01

    Full Text Available Background of study. Prone position is one of the most complex positions for anesthesiologist as it is accompanied by several physiological changes that can lead to specific complications. Hemodynamic changes are most controversial.Aim of study was to establish hemodynamic changes in non-anaesthetized patients in prone position depending on body mass index.Material and methods. We examined central hemodynamics in 40 patients the day before surgery using thoracic rheography in supine position, in prone position 5 min after turning and in prone position 20 min after turning. Patients were divided into 2 groups according to body mass index (18-25 and 26-35.Results. Patients with normal body weight did not have any hemodynamic changes after turning to prone position. Patients with increased body weight had higher cardiac index. After turning to prone position obese patients’ cardiac output and cardiac index reduced 22% comparing with supine position. After 20 min in prone position these hemodynamic parameters were found to be reduced to the same level.Conclusion. Significant hemodynamic changes after turning from supine to prone position were revealed only in patients with increased body mass index. In these patients cardiac index in prone position was reduced by 22% comparing to supine position

  10. CT of hemodynamically unstable abdominal trauma

    International Nuclear Information System (INIS)

    Petridis, A.; Pilavaki, M.; Vafiadis, E.; Palladas, P.; Finitsis, S.; Drevelegas, A.

    1999-01-01

    This article is an appraisal of the use of CT in the management of patients with unstable abdominal trauma. We examined 41 patients with abdominal trauma using noncontrast dynamic CT. In 17 patients a postcontrast dynamic CT was also carried out. On CT, 25 patients had hemoperitoneum. Thirteen patients had splenic, 12 hepatic, 6 pancreatic, 8 bowel and mesenteric, 12 renal and 2 vascular injuries. Seven patients had retroperitoneal and 2 patients adrenal hematomas. All but five lesions (three renal, one pancreatic, and one splenic) were hypodense when CT was performed earlier than 8 h following the injury. Postcontrast studies (n = 17), revealed 4 splenic, 3 hepatic, 1 pancreatic, 3 renal, and 2 bowel and mesenteric injuries beyond what was found on noncontrast CT. Surgical confirmation (n = 21) was obtained in 81.81 % of splenic, 66.66 % of hepatic, 83.33 % of pancreatic, 100 % of renal, 100 % of retroperitoneal, and 85.71 % of bowel and mesenteric injuries. The majority of false diagnoses was obtained with noncontrast studies. Computed tomography is a remarkable method for evaluation and management of patients with hemodynamically unstable abdominal trauma, but only if it is revealed in the emergency room. Contrast injection, when it could be done, revealed lesions that were not suspected on initial plain scans. (orig.)

  11. CT of hemodynamically unstable abdominal trauma

    Energy Technology Data Exchange (ETDEWEB)

    Petridis, A.; Pilavaki, M.; Vafiadis, E.; Palladas, P.; Finitsis, S.; Drevelegas, A. [Department of Radiology, General Hospital ``G. Papanikolaou,`` Thessaloniki (Greece)

    1999-03-01

    This article is an appraisal of the use of CT in the management of patients with unstable abdominal trauma. We examined 41 patients with abdominal trauma using noncontrast dynamic CT. In 17 patients a postcontrast dynamic CT was also carried out. On CT, 25 patients had hemoperitoneum. Thirteen patients had splenic, 12 hepatic, 6 pancreatic, 8 bowel and mesenteric, 12 renal and 2 vascular injuries. Seven patients had retroperitoneal and 2 patients adrenal hematomas. All but five lesions (three renal, one pancreatic, and one splenic) were hypodense when CT was performed earlier than 8 h following the injury. Postcontrast studies (n = 17), revealed 4 splenic, 3 hepatic, 1 pancreatic, 3 renal, and 2 bowel and mesenteric injuries beyond what was found on noncontrast CT. Surgical confirmation (n = 21) was obtained in 81.81 % of splenic, 66.66 % of hepatic, 83.33 % of pancreatic, 100 % of renal, 100 % of retroperitoneal, and 85.71 % of bowel and mesenteric injuries. The majority of false diagnoses was obtained with noncontrast studies. Computed tomography is a remarkable method for evaluation and management of patients with hemodynamically unstable abdominal trauma, but only if it is revealed in the emergency room. Contrast injection, when it could be done, revealed lesions that were not suspected on initial plain scans. (orig.) With 6 figs., 5 tabs., 20 refs.

  12. [Hemodynamic phenomena in retrobulhar and eyeball vessels].

    Science.gov (United States)

    Modrzejewska, Monika

    2011-01-01

    The purpose of this review was to evaluate factors connected with blood flow and indices regulating vascular diameter and some parameters influencing retrobulbar circulation such as type of vascular resistance, anatomical structure of vascular wall and vessel lumen. Neurogenic and angiogenic factors, rheological blood composition, presence of anatomical and pathological obstructions on blood flow pathway as well as degree of development of collateral circulation pathways--have influence on the volume and blood flow velocity in eyeball. There were discussed bulbar circulation hemodynamics, emphasizing the importance of perfusion pressure. The role of risk factors was underlined for pathological lesions in vessels supplying blood to eyeball and in ophthalmic artery (OA) and its collaterals, in central retinal artery (CRA) as well as posterior ciliary arteries (PCAs), and in venous system carrying away blood from eye. IN CONCLUSION--the results of many studies of retrobulbar blood flow in different types of ophthalmic diseases of the vascular etiopathogenesis indicate that registry of the mean values of blood flow parameters and vascular resistance indices parallel to measurement of blood flow spectrum in OA, CRA, PCAs arteries, might contribute much information to explain or to evaluate nature of pathological changes in retinal and choroidal circulation.

  13. Clinical, morphological, and hemodynamic independent characteristic factors for rupture of posterior communicating artery aneurysms.

    Science.gov (United States)

    Zhang, Ying; Jing, Linkai; Liu, Jian; Li, Chuanhui; Fan, Jixing; Wang, Shengzhang; Li, Haiyun; Yang, Xinjian

    2016-08-01

    To identify clinical, morphological, and hemodynamic independent characteristic factors that discriminate posterior communicating artery (PCoA) aneurysm rupture status. 173 patients with single PCoA aneurysms (108 ruptured, 65 unruptured) between January 2012 and June 2014 were retrospectively collected. Patient-specific models based on their three-dimensional digital subtraction angiography images were constructed and analyzed by a computational fluid dynamic method. All variables were analyzed by univariate analysis and multivariate logistic regression analysis. Two clinical factors (younger age and atherosclerosis), three morphological factors (higher aspect ratio, bifurcation type, and irregular shape), and six hemodynamic factors (lower mean and minimum wall shear stress, higher oscillatory shear index, a greater portion of area under low wall shear stress, unstable and complex flow pattern) were significantly associated with PCoA aneurysm rupture. Independent factors characterizing the rupture status were identified as age (OR 0.956, p=0.015), irregular shape (OR 6.709, pPCoA aneurysm rupture were younger age, irregular shape, and low minimum wall shear stress. This may be useful for guiding risk assessments and subsequent treatment decisions for PCoA aneurysms. 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/

  14. Effects of Propofol and Midazolam on Newborns’ Apgar Scores and Mothers’ Hemodynamic under Spinal Anesthesia

    Directory of Open Access Journals (Sweden)

    Navid Kalani

    2016-05-01

    Full Text Available At present, cesarean section is the most prevalent surgical procedure in women and the anesthesia performed for it has turned into a selective technique. This study compared the effects of midazolam and propofol on newborns’ Apgar scores and on the hemodynamic status of the mothers undergoing cesarean sections. This research, in the form of a double-blind clinical trial, was carried out on forty-two15 - 35 year-old of class ASAI and II pregnant women who underwent cesarean section. Using the simple random method, they were divided into two groups of equal members: 21 in the Propofol and 21 in the midazolam groups. The newborns’ Apgar scores were recorded 1 and 5 minutes after birth and the mothers’ hemodynamic status 3, 5, 10, 15, 30, 60 minutes into the surgical procedure. The data was analyzed using SPSS, the repeated measurement test, and the independent t-test. One and five minutes after birth, there were no significant differences between the newborns’ Apgar scores in the two groups (p=0.08, or between the two groups (p=0.33. Results showed there were no statistically significant differences between the Apgar scores of the newborns at low doses of midazolam and propofol.

  15. Stable convergence and stable limit theorems

    CERN Document Server

    Häusler, Erich

    2015-01-01

    The authors present a concise but complete exposition of the mathematical theory of stable convergence and give various applications in different areas of probability theory and mathematical statistics to illustrate the usefulness of this concept. Stable convergence holds in many limit theorems of probability theory and statistics – such as the classical central limit theorem – which are usually formulated in terms of convergence in distribution. Originated by Alfred Rényi, the notion of stable convergence is stronger than the classical weak convergence of probability measures. A variety of methods is described which can be used to establish this stronger stable convergence in many limit theorems which were originally formulated only in terms of weak convergence. Naturally, these stronger limit theorems have new and stronger consequences which should not be missed by neglecting the notion of stable convergence. The presentation will be accessible to researchers and advanced students at the master's level...

  16. stableGP

    Data.gov (United States)

    National Aeronautics and Space Administration — The code in the stableGP package implements Gaussian process calculations using efficient and numerically stable algorithms. Description of the algorithms is in the...

  17. Angina Pectoris (Stable Angina)

    Science.gov (United States)

    ... Peripheral Artery Disease Venous Thromboembolism Aortic Aneurysm More Angina Pectoris (Stable Angina) Updated:Aug 21,2017 You may have heard the term “angina pectoris” or “stable angina” in your doctor’s office, ...

  18. Hemodynamics Modeling and Simulation of Anterior Communicating Artery Aneurysms

    Directory of Open Access Journals (Sweden)

    Jianjun Li

    2014-07-01

    Full Text Available It is a general agreement that hemodynamics plays very important role in the initiation, growth, and rupture of cerebral aneurysms and hemodynamics in the anterior communicating artery aneurysms is considered the most complex in all cerebral aneurysms and it is difficult to find some reasonable relationship between the hemodynamics parameters and the rupture risk. In this paper, the 3D geometries of four anterior communicating artery aneurysms were generated from the CTA data and the computational models with bilateral feeding arteries for the four aneurysms were constructed. The blood flow was simulated by computational fluid dynamics software and the hemodynamics parameters such as velocity, wall shear stress, and oscillatory shear index were calculated. The following results were observed: one of the four models only needs the left feeding artery; the max normalized wall shear stress locates at the aneurysmal neck of the largest aneurysm; the max oscillatory shear index locates at the aneurysmal sac of the largest aneurysm. The conclusion was drawn that the anterior communicating artery aneurysm has higher rupture risk from the hemodynamics viewpoint if the max wall shear stress locates at the neck and the max oscillatory shear index locates at the dome.

  19. Unraveling the relationship between arterial flow and intra-aneurysmal hemodynamics.

    Science.gov (United States)

    Morales, Hernán G; Bonnefous, Odile

    2015-02-26

    Arterial flow rate affects intra-aneurysmal hemodynamics but it is not clear how their relationship is. This uncertainty hinders the comparison among studies, including clinical evaluations, like a pre- and post-treatment status, since arterial flow rates may differ at each time acquisition. The purposes of this work are as follows: (1) To study how intra-aneurysmal hemodynamics changes within the full physiological range of arterial flow rates. (2) To provide characteristic curves of intra-aneurysmal velocity, wall shear stress (WSS) and pressure as functions of the arterial flow rate. Fifteen image-based aneurysm models were studied using computational fluid dynamics (CFD) simulations. The full range of physiological arterial flow rates reported in the literature was covered by 11 pulsatile simulations. For each aneurysm, the spatiotemporal-averaged blood flow velocity, WSS and pressure were calculated. Spatiotemporal-averaged velocity inside the aneurysm linearly increases as a function of the mean arterial flow (minimum R(2)>0.963). Spatiotemporal-averaged WSS and pressure at the aneurysm wall can be represented by quadratic functions of the arterial flow rate (minimum R(2)>0.996). Quantitative characterizations of spatiotemporal-averaged velocity, WSS and pressure inside cerebral aneurysms can be obtained with respect to the arterial flow rate. These characteristic curves provide more information of the relationship between arterial flow and aneurysm hemodynamics since the full range of arterial flow rates is considered. Having these curves, it is possible to compare experimental studies and clinical evaluations when different flow conditions are used. Copyright © 2015 Elsevier Ltd. All rights reserved.

  20. Central Hemodynamic Features in Elderly Patients During General Anesthesia with Sevoflurane

    Directory of Open Access Journals (Sweden)

    O.I. Petrov

    2011-01-01

    Full Text Available Objective: to reduce the number of perioperative cardiovascular events in elderly patients during traditional cholecystectomy, by using anesthesia based on sevoflurane (SF and fentanyl (FL. Subjects and methods. Forty-eight patients aged 60 to 75 years, who were divided into 2 groups, operated on by a classical surgical technique for chronic calculous cholecystitis in the presence of concomitant coronary heart disease and essential hypertension, and had grade 3 surgical risk according to the classification of the Moscow Research Society of Anesthesiologists and Reanimatologists, were examined. Premedicaton was routine. The induction of anesthesia was as follows: intravenous propofol (PF (1.8±0.2 mg/kg and FL (2.2±0.4 mg/kg in Groups 1 and 2. General anesthesia (GA was maintained by SF (1.1±0.2 MAC and FL (2.4±0.4 jBg/kg/hr in Group 1 (n=25 and by PF (2.0—4.0 mg/kg/hr and FL (3.5±0.7 ^Bg/kg/hr in Group 2 (n=23. In both groups, mechanical ventilation was as follows: N2O:O2 = 2:1; air flow, 6 l/min. Myoplegia was rocuronium bromide (RB (0.075—0.1 mg/kg in Group 1 and RB (0.15 mg/kg in Group 2. Hemodynamics was studied during 5 stages of surgery. Results. Central hemodynamics (CH was rather stable in patients after GA with SF. Significant CH changes were noted only during the traumatic stage of surgery, which were less pronounced than those in patients following GA with PF. CH parameters returned gradually to the baseline values at the end of surgery and virtually to the background values after tracheal extubation. The patients under GA with PF showed significant CH changes at all stages of the study. Conclusion. Analysis of the systemic hemodynamic changes induced by the use of SF and PF suggests that GA with SF in elderly patients is more preferable than that in those with PF. Key words: sevoflurane, hemodynamics, elderly.

  1. The Effect of Human-Immunodeficiency Virus Status on Outcomes in Penetrating Abdominal Trauma: An Interim Analysis.

    Science.gov (United States)

    McPherson, Deidre; Neuhaus, Valentin; Dhar, Rohin; Edu, Sorin; Nicol, Andrew J; Navsaria, Pradeep H

    2018-01-31

    The purpose of this study was to determine whether the outcomes of hemodynamically stable patients undergoing exploratory laparotomy for penetrating abdominal trauma differed as a result of their HIV status. This was an observational, prospective study from February 2016 to May 2017. All hemodynamically stable patients with penetrating abdominal trauma requiring a laparotomy were included. The mechanism of injury, the HIV status, age, the penetrating abdominal trauma index (PATI), and the revised trauma score (RTS) were entered into a binary logistic regression model. Outcome parameters were in-hospital death, morbidity, admission to intensive care unit (ICU), relaparotomy within 30 days, and length of stay longer than 30 days. A total of 209 patients, 94% male, with a mean age of 29 ± 10 years were analysed. Twenty-eight patients (13%) were HIV positive. The two groups were comparable. Ten (4.8%) laparotomies were negative. There were two (0.96%) deaths, both in the HIV negative group. The complication rate was 34% (n = 72). Twenty-nine patients (14%) were admitted to the ICU. A higher PATI, older age, and a lower RTS were significant risk factors for ICU admission. After 30 days, 12 patients (5.7%) were still in hospital. Twenty-four patients (11%) underwent a second laparotomy. The PATI score was the single independent predictor for complications, relaparotomy, and hospital stay longer than 30 days. Preliminary results reveal that HIV status does not influence outcomes in patients with penetrating abdominal trauma.

  2. 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.

  3. Invasive and noninvasive hemodynamic monitoring of patients with cerebrovascular accidents.

    Science.gov (United States)

    Velmahos, G C; Wo, C C; Demetriades, D; Bishop, M H; Shoemaker, W C

    1998-01-01

    Seventeen patients with hemodynamic instability from acute cerebrovascular accidents were evaluated shortly after arrival at the emergency department of a university-run county hospital with both invasive Swan-Ganz pulmonary artery catheter placement and a new, noninvasive, thoracic electrical bioimpedance device. Values were recorded and temporal patterns of survivors and nonsurvivors were described. Cardiac indices obtained simultaneously by the 2 techniques were compared. Of the 17 patients, 11 (65%) died. Survivors had higher values than nonsurvivors for mean arterial pressure, cardiac index, and oxygen saturation, delivery, and consumption at comparable times. Cardiac index values, as measured by invasive and noninvasive methods, were correlated. We concluded that hemodynamic monitoring in an acute care setting may recognize temporal circulatory patterns associated with outcome. Noninvasive electrical bioimpedance technology offers a new method for early hemodynamic evaluation. Further research in this area is warranted. PMID:9682626

  4. [Unit of hemodynamics: the production of the knowledge].

    Science.gov (United States)

    Linch, Graciele Fernanda da Costa; Guido, Laura de Azevedo; Pitthan, Luiza de Oliveira; Umann, Juliane

    2009-12-01

    This study aimed at doing an integrative review that has as objective to investigate what has been published on nursing in hemodynamic in the following data bases: Scientific Electronic Library Online (SciELO), Medical Literature Analysis and Retrieval System Online (MEDLINE), Latin American and Caribbean Health Sciences (LILACS), and Nursing Database (BDENF); with the descriptors: Enfermagem and Hemodinâmica and Nursing and Hemodynamics. The data indicate that the studies in his majority were developed by nurses, and made a list to the presence of nursing, there were still boarded aspects made a list to the reprocess of catheters and health of the professionals of nursing. Nevertheless, it is noticeable that the publication of works connected with the thematic of hemodynamic is limited. However, they demonstrate the predominance of inquiries and reports making a list to the aspects of the presence of nursing in this sector which may represent the necessities and the problems that permeate the work.

  5. The nursing perspective on monitoring hemodynamics and oxygen transport.

    Science.gov (United States)

    Tucker, Dawn; Hazinski, Mary Fran

    2011-07-01

    Maintenance of adequate systemic oxygen delivery requires careful clinical assessment integrated with hemodynamic measurements and calculations to detect and treat conditions that may compromise oxygen delivery and lead to life-threatening shock, respiratory failure, or cardiac arrest. The bedside nurse constantly performs such assessments and measurements to detect subtle changes and trends in patient condition. The purpose of this editorial is to highlight nursing perspectives about the hemodynamic and oxygen transport monitoring systems summarized in the Pediatric Cardiac Intensive Care Society Evidence- Based Review and Consensus Statement on Monitoring of Hemodynamics and Oxygen Transport Balance. There is no substitute for the observations of a knowledgeable and experienced clinician who understands the patient's condition and potential causes of deterioration and is able to evaluate response to therapy.

  6. 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

  7. Implant experience with an implantable hemodynamic monitor for the management of symptomatic heart failure.

    Science.gov (United States)

    Steinhaus, David; Reynolds, Dwight W; Gadler, Fredrik; Kay, G Neal; Hess, Mike F; Bennett, Tom

    2005-08-01

    Management of congestive heart failure is a serious public health problem. The use of implantable hemodynamic monitors (IHMs) may assist in this management by providing continuous ambulatory filling pressure status for optimal volume management. The Chronicle system includes an implanted monitor, a pressure sensor lead with passive fixation, an external pressure reference (EPR), and data retrieval and viewing components. The tip of the lead is placed near the right ventricular outflow tract to minimize risk of sensor tissue encapsulation. Implant technique and lead placement is similar to that of a permanent pacemaker. After the system had been successfully implanted in 148 patients, the type and frequency of implant-related adverse events were similar to a single-chamber pacemaker implant. R-wave amplitude was 15.2 +/- 6.7 mV and the pressure waveform signal was acceptable in all but two patients in whom presence of artifacts required lead repositioning. Implant procedure time was not influenced by experience, remaining constant throughout the study. Based on this evaluation, permanent placement of an IHM in symptomatic heart failure patients is technically feasible. Further investigation is warranted to evaluate the use of the continuous hemodynamic data in management of heart failure patients.

  8. Hemodynamics and vasopressor support in therapeutic hypothermia after cardiac arrest

    DEFF Research Database (Denmark)

    Bro-Jeppesen, John; Kjaergaard, Jesper; Søholm, Helle

    2014-01-01

    AIM: Inducing therapeutic hypothermia (TH) in Out-of-Hospital Cardiac Arrest (OHCA) can be challenging due to its impact on central hemodynamics and vasopressors are frequently used to maintain adequate organ perfusion. The aim of this study was to assess the association between level of vasopres......AIM: Inducing therapeutic hypothermia (TH) in Out-of-Hospital Cardiac Arrest (OHCA) can be challenging due to its impact on central hemodynamics and vasopressors are frequently used to maintain adequate organ perfusion. The aim of this study was to assess the association between level...

  9. 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...... patients and controls respectively. CONCLUSION: SVI decreased significantly in Fontan patients near the end of maximal effort exercise. The low SVI at maximal exercise was the most important hemodynamic factor limiting exercise capacity in Fontan patients, whereas chronotropic impairment had a smaller...

  10. Development of stable isotope manufacturing in Russia

    International Nuclear Information System (INIS)

    Pokidychev, A.; Pokidycheva, M.

    1999-01-01

    For the past 25 years, Russia has relied heavily on the electromagnetic separation process for the production of middle and heavy mass stable isotopes. The separation of most light isotopes had been centered in Georgia which, after the collapse of the USSR, left Russia without this capability. In the mid-1970s, development of centrifuge technology for the separation of stable isotopes was begun. Alternative techniques such as laser separation, physical-chemical methods, and ion cyclotron resonance have also been investigated. Economic considerations have played a major role in the development and current status of the stable isotope enrichment capabilities of Russia

  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. 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...

  13. 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.

  14. 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

  15. Diagnostic possibilities of radionuclide investigation in patterns with stable and unstable angina pectoris

    International Nuclear Information System (INIS)

    Ponomareva, A.G.; Zudbinov, Yu.I.; Sokolov, O.K.; Kudinov, V.I.

    1986-01-01

    Myocardial radiocardiography and scintigraphy with 99m Tc-pyrophosphate was performed in 58 patients with stable angina and 60 patients with unstable angina. In patients with stable angina, positive scintigrams were mostly recorded after anginal attacks. Their central hemodynamic parameters deteriorated progressively as angina increased in severity. Patients with unstable angina typically showed myocardial accumulation of the label that was unrelated to anginal attacks and recordable by direct-projection scintigraphy. The assessment of myocardial radiocardiographic and scintigraphic data allows one to differentiate between stable and unstable angina

  16. Stable Boundary Layer Issues

    OpenAIRE

    Steeneveld, G.J.

    2012-01-01

    Understanding and prediction of the stable atmospheric boundary layer is a challenging task. Many physical processes are relevant in the stable boundary layer, i.e. turbulence, radiation, land surface coupling, orographic turbulent and gravity wave drag, and land surface heterogeneity. The development of robust stable boundary layer parameterizations for use in NWP and climate models is hampered by the multiplicity of processes and their unknown interactions. As a result, these models suffer ...

  17. Prospective evaluation of intraoperative hemodynamics in liver transplantation with whole, partial and DCD grafts

    NARCIS (Netherlands)

    Sainz-Barriga, M; Reyntjens, K; Costa, M G; Scudeller, L; Rogiers, X; Wouters, P; de Hemptinne, B; Troisi, R I

    The interaction of systemic hemodynamics with hepatic flows at the time of liver transplantation (LT) has not been studied in a prospective uniform way for different types of grafts. We prospectively evaluated intraoperative hemodynamics of 103 whole and partial LT. Liver graft hemodynamics were

  18. 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

  19. 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.

  20. White-collar workers' hemodynamic responses during working hours.

    Science.gov (United States)

    Liu, Xinxin; Iwakiri, Kazuyuki; Sotoyama, Midori

    2017-08-08

    In the present study, two investigations were conducted at a communication center, to examine white-collar workers' hemodynamic responses during working hours. In investigation I, hemodynamic responses were measured on a working day; and in investigation II, cardiovascular responses were verified on both working and non-working days. In investigation I, blood pressure, cardiac output, heart rate, stroke volume, and total peripheral resistance were measured in 15 workers during working hours (from 9:00 am to 18:00 pm) on one working day. Another 40 workers from the same workplace participated in investigation II, in which blood pressure and heart rate were measured between the time workers arose in the morning until they went to bed on 5 working days and 2 non-working days. The results showed that blood pressure increased and remained at the same level during working hours. The underlying hemodynamics of maintaining blood pressure, however, changed between the morning and the afternoon on working days. Cardiac responses increased in the afternoon, suggesting that cardiac burdens increase in the afternoon on working days. The present study suggested that taking underlying hemodynamic response into consideration is important for managing the work-related cardiovascular burden of white-collar workers.

  1. 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

  2. Clinical review: Update on hemodynamic monitoring - a consensus of 16.

    NARCIS (Netherlands)

    Vincent, J.L.; Rhodes, A.; Perel, A.; Martin, G.S.; Rocca, G.D.; Vallet, B.; Pinsky, M.R.; Hofer, C.K.; Teboul, J.L.; Boode, W.P. de; Scolletta, S.; Viellard-Baron, A.; Backer, D. de; Walley, K.R.; Maggiorini, M.; Singer, M.

    2011-01-01

    Hemodynamic monitoring plays a fundamental role in the management of acutely ill patients. With increased concerns about the use of invasive techniques, notably the pulmonary artery catheter, to measure cardiac output, recent years have seen an influx of new, less-invasive means of measuring

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

    Directory of Open Access Journals (Sweden)

    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. 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.

  5. Neonatal Hemodynamics: From Developmental Physiology to Comprehensive Monitoring

    Directory of Open Access Journals (Sweden)

    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.

  6. 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.

  7. 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...

  8. 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 this appro...

  9. 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.

  10. 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.

  11. Intraosseous anesthesia in hemodynamic studies in children with cardiopathy.

    Science.gov (United States)

    Aliman, Ana Cristina; Piccioni, Marilde de Albuquerque; Piccioni, João Luiz; Oliva, José Luiz; Auler Júnior, José Otávio Costa

    2011-01-01

    Intraosseous (IO) access has been used with good results in emergency situations, when venous access is not available for fluids and drugs infusion. The objective of this study was to evaluate IO a useful technique for anesthesia and fluids infusion during hemodynamic studies and when peripheral intravascular access is unobtainable. The setting was an university hospital hemodynamics unit, and the subjects were twenty one infants with congenital heart disease enrolled for elective hemodynamic study diagnosis. This study compared the effectiveness of IO access in relation to IV access for infusion of anesthetics agents (ketamine, midazolam, and fentanyl) and fluids during hemodynamic studies. The anesthetic induction time, procedure duration, anesthesia recovery time, adequate hydration, and IV and IO puncture complications were compared between groups. The puncture time was significantly smaller in IO group (3.6 min) that in IV group (9.6 min). The anesthetic onset time (56.3 second) for the IV group was faster than IO group (71.3 second). No significant difference between groups were found in relation to hydration (IV group, 315.5 mL vs IO group, 293.2 mL), and anesthesia recovery time (IO group, 65.2 min vs IV group, 55.0 min). The puncture site was reevaluated after 7 and 15 days without signs of infection or other complications. Results showed superiority for IO infusion when considering the puncture time of the procedure. Due to its easy manipulation and efficiency, hydration and anesthesia by IO access was satisfactory for hemodynamic studies without the necessity of other infusion access. Copyright © 2011 Elsevier Editora Ltda. All rights reserved.

  12. Reliability of oscillometric central hemodynamic responses to an orthostatic challenge.

    Science.gov (United States)

    Stoner, Lee; Bonner, Chantel; Credeur, Daniel; Lambrick, Danielle; Faulkner, James; Wadsworth, Daniel; Williams, Michelle A

    2015-08-01

    Monitoring central hemodynamic responses to an orthostatic challenge may provide important insight into autonomic nervous system function. Oscillometric pulse wave analysis devices have recently emerged, presenting clinically viable options for investigating central hemodynamic properties. The purpose of the current study was to determine whether oscillometric pulse wave analysis can be used to reliably (between-day) assess central blood pressure and central pressure augmentation (augmentation index) responses to a 5 min orthostatic challenge (modified tilt-table). Twenty healthy adults (26.4 y (SD 5.2), 55% F, 24.7 kg/m(2) (SD 3.8)) were tested on 3 different mornings in the fasted state, separated by a maximum of 7 days. Central hemodynamic variables were assessed on the left arm using an oscillometric device. Repeated measures analysis of variance indicated a significant main effect of the modified tilt-table for all central hemodynamic variables (P response to the tilt, central diastolic pressure increased by 4.5 mmHg (CI: 2.6, 6.4), central systolic blood pressure increased by 2.3 (CI: 4.4, 0.16) mmHg, and augmentation index decreased by an absolute - 5.3%, (CI: -2.7, -7.9%). The intra-class correlation coefficient values for central diastolic pressure (0.83-0.86), central systolic blood pressure (0.80-0.87) and AIx (0.79-0.82) were above the 0.75 criterion in both the supine and tilted positions, indicating excellent between-day reliability. Central hemodynamic responses to an orthostatic challenge can be assessed with acceptable between-day reliability using oscillometric pulse wave analysis. Copyright © 2015 Elsevier Ireland Ltd. All rights reserved.

  13. Stable isotopes labelled compounds

    International Nuclear Information System (INIS)

    1982-09-01

    The catalogue on stable isotopes labelled compounds offers deuterium, nitrogen-15, and multiply labelled compounds. It includes: (1) conditions of sale and delivery, (2) the application of stable isotopes, (3) technical information, (4) product specifications, and (5) the complete delivery programme

  14. Evolutionary Stable Strategy

    Indian Academy of Sciences (India)

    Home; Journals; Resonance – Journal of Science Education; Volume 21; Issue 9. Evolutionary Stable Strategy: Application of Nash Equilibrium in Biology. General Article Volume 21 Issue 9 September 2016 pp 803- ... Keywords. Evolutionary game theory, evolutionary stable state, conflict, cooperation, biological games.

  15. Stable Boundary Layer Issues

    NARCIS (Netherlands)

    Steeneveld, G.J.

    2012-01-01

    Understanding and prediction of the stable atmospheric boundary layer is a challenging task. Many physical processes are relevant in the stable boundary layer, i.e. turbulence, radiation, land surface coupling, orographic turbulent and gravity wave drag, and land surface heterogeneity. The

  16. Hemodynamic stability ensured by a low dose, low volume, unilateral hypobaric spinal block: modification of a technique.

    Science.gov (United States)

    Elzinga, L; Marcus, M; Peek, D; Borg, P; Jansen, J; Koster, J; Enk, D

    2009-01-01

    We report the case of an 89-year-old female with a history of arterial hypertension, intermittent rapid atrial fibrillation and severe aortic valve stenosis, suffering from femoral neck fracture. Hyperbaric unilateral spinal anesthesia is a known technique to obtain stable hemodynamics combined with the possibility of continuous neurologic evaluation and preservation of cognitive functions. Because a hyperbaric unilateral technique can be very painful in case of traumatic hip fracture, a low dose, low volume, unilateral hypobaric spinal block may be an adequate alternative. In the present case report, a unilateral hypobaric spinal anesthesia was performed using 5 mg of bupivacaine in a 1.5 mL volume and a slow and steady, "air-buffered", directed injection technique, to allow an urgent hip arthroplasty. During surgery the patient was kept in the lateral recumbent position. Hemodynamics remained stable throughout the entire procedure without any need for vasoconstrictors. The impact of aortic valve stenosis combined with atrial fibrillation on anesthetic management and our considerations to opt for a unilateral hypobaric spinal anesthesia are discussed.

  17. SUCCESSFUL APPLICATION OF PERIPHERAL VENO-ARTERIAL EXTRACORPOREAL MEMBRANE OXYGENATION FOR CARDIAC ALLOGRAFT ANTIBODY-MEDIATED REJECTION WITH SEVERE HEMODYNAMIC COMPROMISE

    Directory of Open Access Journals (Sweden)

    V. N. Poptsov

    2015-01-01

    Hg, PAP 31/21/12 mm Hg, PCWP 12 mm Hg, CI 3,4 l/min/м2, HR 85 in min, LVEF 53%, IVS 1.3 cm, mitral valve regurgitation <1 degree, inotropic support was discontinued. Control EMB showed resolution of AMR. Duration of VA ECMO was 7 days. Patient was discharged from ICU on the 2nd and 26th day after VA ECMO in stable clinical status. Conclusion. VA ECMO should be crucial component of treatment of cardiac allogaft antibody-mediated rejection with severe hemodynamic compromise. 

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

    International Nuclear Information System (INIS)

    Choe, Ku Ok; Suh, Jung Ho; Park, Chang Yun; Choi, Byung So

    1973-01-01

    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

  19. 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

  20. Normal modified stable processes

    DEFF Research Database (Denmark)

    Barndorff-Nielsen, Ole Eiler; Shephard, N.

    2002-01-01

    Gaussian (NGIG) laws. The wider framework thus established provides, in particular, for added flexibility in the modelling of the dynamics of financial time series, of importance especially as regards OU based stochastic volatility models for equities. In the special case of the tempered stable OU process......This paper discusses two classes of distributions, and stochastic processes derived from them: modified stable (MS) laws and normal modified stable (NMS) laws. This extends corresponding results for the generalised inverse Gaussian (GIG) and generalised hyperbolic (GH) or normal generalised inverse...

  1. Applications of stable isotopes

    International Nuclear Information System (INIS)

    Letolle, R.; Mariotti, A.; Bariac, T.

    1991-06-01

    This report reviews the historical background and the properties of stable isotopes, the methods used for their measurement (mass spectrometry and others), the present technics for isotope enrichment and separation, and at last the various present and foreseeable application (in nuclear energy, physical and chemical research, materials industry and research; tracing in industrial, medical and agronomical tests; the use of natural isotope variations for environmental studies, agronomy, natural resources appraising: water, minerals, energy). Some new possibilities in the use of stable isotope are offered. A last chapter gives the present state and forecast development of stable isotope uses in France and Europe

  2. ECG Markers of Hemodynamic Improvement in Patients with Pulmonary Hypertension

    Directory of Open Access Journals (Sweden)

    Marcin Waligóra

    2018-01-01

    Full Text Available Introduction. Several diagnostic tests have been recommended for risk assessment in pulmonary hypertension (PH, but the role of electrocardiography (ECG in monitoring of PH patients has not been yet established. Therefore the aim of the study was to evaluate which ECG patterns characteristic for pulmonary hypertension can predict hemodynamic improvement in patients treated with targeted therapies. Methods. Consecutive patients with pulmonary arterial hypertension (PAH or chronic thromboembolic pulmonary hypertension (CTEPH were eligible to be included if they had had performed two consecutive right heart catheterization (RHC procedures before and after starting of targeted therapies. Patients were followed up from June 2009 to July 2017. ECG patterns of right ventricular hypertrophy according to American College of Cardiology Foundation were assessed. Results. We enrolled 80 patients with PAH and 11 patients with inoperable CTEPH. The follow-up RHC was performed within 12.6±10.0 months after starting therapy. Based on median change of pulmonary vascular resistance, we divided our patients into two subgroups: with and without significant hemodynamic improvement. RV1, max⁡RV1,2 + max⁡SI,aVL-SV1, and PII improved along with the improvement of hemodynamic parameters including PVR. They predicted hemodynamic improvement with similarly good accuracy as shown in ROC analysis: RV1 (AUC: 0.75; 95% CI: 0.63–0.84, PII (AUC: 0.67, 95% CI: 0.56–0.77, and max⁡RV1,2+max⁡SI,aVL-SV1 (0.73; 95% CI: 0.63–0.82. In Cox regression only change in RV1 remained significant mortality predictor (HR: 1.12, 95% CI: 1.01–1.24. Conclusion. Electrocardiogram may be useful in predicting hemodynamic effects of targeted therapy in precapillary pulmonary hypertension. Decrease of RV1, max⁡RV1,2+max⁡SI,aVL-SV1, and PII corresponds with hemodynamic improvement after treatment. Of these changes a decrease of R wave amplitude in V1 is associated with better

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

    Directory of Open Access Journals (Sweden)

    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

  4. Analysing Stable Time Series

    National Research Council Canada - National Science Library

    Adler, Robert

    1997-01-01

    We describe how to take a stable, ARMA, time series through the various stages of model identification, parameter estimation, and diagnostic checking, and accompany the discussion with a goodly number...

  5. The effect of combined conventional and modified ultrafiltration on mechanical ventilation and hemodynamic changes in congenital heart surgery

    Directory of Open Access Journals (Sweden)

    Mohsen Ziyaeifard

    2016-01-01

    Full Text Available Background: Cardiopulmonary bypass is associated with increased fluid accumulation around the heart which influences pulmonary and cardiac diastolic function. The aim of this study was to compare the effects of modified ultrafiltration (MUF versus conventional ultrafiltration (CUF on duration of mechanical ventilation and hemodynamic status in children undergoing congenital heart surgery. Materials and Methods: A randomized clinical trial was conducted on 46 pediatric patients undergoing cardiopulmonary bypass throughout their congenital heart surgery. Arteriovenous MUF plus CUF was performed in 23 patients (intervention group and sole CUF was performed for other 23 patients (control group. In MUF group, arterial cannula was linked to the filter inlet through the arterial line, and for 10 min, 10 ml/kg/min of blood was filtered and returned via cardioplegia line to the right atrium. Different parameters including hemodynamic variables, length of mechanical ventilation, Intensive Care Unit (ICU stay, and inotrope requirement were compared between the two groups. Results: At immediate post-MUF phase, there was a statistically significant increase in the mean arterial pressure, systolic blood pressure, and diastolic blood pressure (P < 0.05 only in the study group. Furthermore, there was a significant difference in time of mechanical ventilation (P = 0.004 and ICU stay (P = 0.007 between the two groups. Inotropes including milrinone (P = 0.04, epinephrine (P = 0.001, and dobutamine (P = 0.002 were used significantly less frequently for patients in the intervention than the control group. Conclusion: Administration of MUF following surgery improves hemodynamic status of patients and also significantly decreases the duration of mechanical ventilation and inotrope requirement within 48 h after surgery.

  6. Chronologic Evaluation of Cerebral Hemodynamics by Dynamic Susceptibility Contrast Magnetic Resonance Imaging After Indirect Bypass Surgery for Moyamoya Disease.

    Science.gov (United States)

    Ishii, Yosuke; Tanaka, Yoji; Momose, Toshiya; Yamashina, Motoshige; Sato, Akihito; Wakabayashi, Shinichi; Maehara, Taketoshi; Nariai, Tadashi

    2017-12-01

    Although indirect bypass surgery is an effective treatment option for patients with ischemic-onset moyamoya disease (MMD), the time point after surgery at which the patient's hemodynamic status starts to improve and the time point at which the improvement reaches a maximum have not been known. The objective of the present study is to evaluate the hemodynamic status time course after indirect bypass surgery for MMD, using dynamic susceptibility contrast-magnetic resonance imaging (DSC-MRI). We retrospectively analyzed the cases of 25 patients with MMD (37 sides; mean age, 14.7 years; range, 3-36 years) who underwent indirect bypass surgery and repeated DSC-MRI measurement within 6 months after the operation. The difference in the mean transit time (MTT) between the target regions and the control region (cerebellum) was termed the MTT delay, and we measured the MTT delay's chronologic changes after surgery. The postoperative MTT delay was 1.81 ± 1.16 seconds within 1 week after surgery, 1.57 ± 1.01 at weeks 1-2, 1.55 ± 0.68 at weeks 2-4, 1.32 ± 0.68 at months 1-2, 0.95 ± 0.32 at months 2-3, and 0.77 ± 0.33 at months 3-6. Compared with the preoperative value (2.11 ± 0.98 seconds), the MTT delay decreased significantly from 2 to 4 weeks after surgery (P surgery began soon after surgery and gradually reached a maximum at 3 months after surgery. DSC-MRI detected small changes in hemodynamic improvement, which are suspected to be caused by the initiation of angiogenesis and arteriogenesis in the early postoperative period. Copyright © 2017. Published by Elsevier Inc.

  7. Differentiation of Constriction and Restriction: Complex Cardiovascular Hemodynamics.

    Science.gov (United States)

    Geske, Jeffrey B; Anavekar, Nandan S; Nishimura, Rick A; Oh, Jae K; Gersh, Bernard J

    2016-11-29

    Differentiation of constrictive pericarditis (CP) from restrictive cardiomyopathy (RCM) is a complex and often challenging process. Because CP is a potentially curable cause of heart failure and therapeutic options for RCM are limited, distinction of these 2 conditions is critical. Although different in regard to etiology, prognosis, and treatment, CP and RCM share a common clinical presentation of predominantly right-sided heart failure, in the absence of significant left ventricular systolic dysfunction or valve disease, due to impaired ventricular diastolic filling. Fundamental to the diagnosis of either condition is a clear understanding of the underlying hemodynamic principles and pathophysiology. We present a contemporary review of the pathophysiology, hemodynamics, diagnostic assessment, and therapeutic approach to patients presenting with CP and RCM. Copyright © 2016 American College of Cardiology Foundation. Published by Elsevier Inc. All rights reserved.

  8. 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

    ≥3 TR underwent high-fidelity invasive hemodynamic exercise testing with simultaneous expired gas analysis and were compared with 13 age- and sex-matched controls. At rest, TR subjects had lower pulmonary blood flow (3.6±0.4 versus 5.1±1.9 L/min; P=0.01), increased right atrial pressure (12±5 versus.......001). TR subjects displayed higher pulmonary capillary wedge pressure with exercise, but this was solely because of RA hypertension (27±9 versus 8±3 mm Hg; P......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 grade...

  9. 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.

  10. Systemic and intracardiac hemodynamic disturbance in complicated forms of hepatocirrhosis

    International Nuclear Information System (INIS)

    Mjasnik, B.N.; Chodzibekov, M.C.; Achmedzanova, S.S.

    1990-01-01

    On the base of radionuclide investigation of systemic and intracardiac hemodynamics was shown that the rate of kinetic variants of hemocirculation does not depend on the stage of portal hypertension in complicated forms of hepatocirrhosis. Blood redistribution in these patients creates volumentrical overload of cardiac ventricles and pulmonary circulation, that is conditioned of additional tension of cardiac muscle and especially of right ventricle myocardium, which reserve rapidly ran out. Operations which increase blood shunt from portal system to superior vena cava raise preload of myocardium that makes the high risk in appearance of cardiac insufficiency, especially of right ventricle in early post operative period. The received data indicated on necessity to take into account the state of intracardiac hemodynamics in selection of surgical approach in patients with complicated forms of hepatocirrhosis. (orig.) [de

  11. Use of active dosemeters as a optimization tool in hemodynamics

    International Nuclear Information System (INIS)

    Nunes, Rafael; Pereira, Dirceu D.; Rodrigues, Barbara B.D.; Ferreira, Esmeralci

    2016-01-01

    Interventional cardiology procedures are, in general, associated with high doses in patients and professionals. The objective of this study is to measure the radiation levels received by professionals .The professional dosimetry was performed in a department of Hemodynamics of University Hospital in Rio de Janeiro. were followed 331 coronary angiography (CA) and 26 percutaneous transluminal coronary angioplasty (PTCA) procedures. For this, were used active dosemeters to measure the radiation levels at the chest of interventional professionals. The results show that average personal equivalent dose of doctors, per procedure was 100 e 154 μSv. On average, nursing technicians and radiologist receive 12 and 10% of doses of physicians, respectively, during CA procedures. From the results, it appears that the doses of hemodynamics exceed the annual dose limit of the standards. The use of lead shielding is presented as an effective action to reduce doses in these workers. (author)

  12. 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.

  13. Continuous Hemodynamic Monitoring in Acute Stroke: An Exploratory Analysis

    Directory of Open Access Journals (Sweden)

    Ayan Sen

    2014-07-01

    Full Text Available Introduction: Non-invasive, continuous hemodynamic monitoring is entering the clinical arena. The primary objective of this study was to test the feasibility of such monitoring in a pilot sample of Emergency Department (ED stroke patients. Secondary objectives included analysis of hemodynamic variability and correlation of continuous blood pressure measurements with standard measurements. Methods: This study was a secondary analysis of 7 stroke patients from a prospectively collected data set of patients that received 2 hours of hemodynamic monitoring in the ED. Stroke patients were included if hemorrhagic or ischemic stroke was confirmed by neuroimaging, and symptom onset was within 24 hours. They were excluded for the presence of a stroke mimic or transient ischemic attack. Monitoring was performed using the Nexfin device (Edwards Lifesciences, Irvine CA. Results: The mean age of the cohort was 71 ± 17 years, 43% were male, and the mean National Institute of Health Stroke Scale (NIHSS was 6.9 ± 5.5. Two patients had hemorrhagic stroke. We obtained 42,456 hemodynamic data points, including beat-to-beat blood pressure measurements with variability of 18 mmHg and cardiac indices ranging from 1.8 to 3.6 l/min/m2. The correlation coefficient between continuous blood pressure measurements with the Nexfin device and standard ED readings was 0.83. Conclusion: This exploratory investigation revealed that continuous, noninvasive monitoring in the ED is feasible in acute stroke. Further research is currently underway to determine how such monitoring may impact outcomes in stroke or replace the need for invasive monitoring. [West J Emerg Med. 2014;15(4:–0.

  14. 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.

  15. Hemodynamics alter arterial low-density lipoprotein metabolism

    International Nuclear Information System (INIS)

    Warty, V.S.; Calvo, W.J.; Berceli, S.A.; Pham, S.M.; Durham, S.J.; Tanksale, S.K.; Klein, E.C.; Herman, I.M.; Borovetz, H.S.

    1989-01-01

    We have investigated the role of hemodynamic factors on low-density lipoprotein transport and metabolism in the intact arterial wall. Freshly excised canine carotid blood vessels were exposed to well-defined pulsatile flow in vitro for continuous periods up to 20 hours. We chose to impose the following hemodynamic conditions on our test carotid arteries: normotension, hypertension (at physiologic flow conditions), and hypertension coupled with elevated flow of canine serum perfusate. In several experiments the effect of endothelial denudation was examined in carotid arteries exposed to normotensive pulsatile flow. A trapped ligand method was used for quantitating low-density lipoprotein uptake and metabolism in the arterial wall. The distribution of both intact and degraded low-density lipoprotein fractions was determined from measurements of radiolabelled low-density lipoprotein activity within thin radial sections of perfused arteries. Our results suggest that both hypertensive hemodynamic simulations exacerbate the uptake of low-density lipoprotein within the arterial wall (by a factor of three to nine). The percentage of low-density lipoprotein that undergoes irreversible degradation falls from 41% under normotensive conditions to below 30% when hypertensive conditions are imposed, indicating that degradative processes are not proportionally elevated with the accelerated influx. A similar pattern is observed for deendothelialized vessels

  16. 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.

  17. 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.

  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. 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.

  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. 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. 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.

  3. 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.

  4. Stable massive particles at colliders

    Energy Technology Data Exchange (ETDEWEB)

    Fairbairn, M.; /Stockholm U.; Kraan, A.C.; /Pennsylvania U.; Milstead, D.A.; /Stockholm U.; Sjostrand, T.; /Lund U.; Skands, P.; /Fermilab; Sloan, T.; /Lancaster U.

    2006-11-01

    We review the theoretical motivations and experimental status of searches for stable massive particles (SMPs) which could be sufficiently long-lived as to be directly detected at collider experiments. The discovery of such particles would address a number of important questions in modern physics including the origin and composition of dark matter in the universe and the unification of the fundamental forces. This review describes the techniques used in SMP-searches at collider experiments and the limits so far obtained on the production of SMPs which possess various colour, electric and magnetic charge quantum numbers. We also describe theoretical scenarios which predict SMPs, the phenomenology needed to model their production at colliders and interactions with matter. In addition, the interplay between collider searches and open questions in cosmology such as dark matter composition are addressed.

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

    Directory of Open Access Journals (Sweden)

    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

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

    Science.gov (United States)

    Caicedo, Alexander; Varon, Carolina; Hunyadi, Borbala; Papademetriou, Maria; Tachtsidis, Ilias; Van Huffel, Sabine

    2016-01-01

    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 + ϵ . 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 3 days of life was used, here SIDE-ObSP decoupled the influence of changes in arterial oxygen saturation from the

  7. Acute Responses of a Physical Training Session with a Nintendo Wii on Hemodynamic Variables of an Individual with Multiple Sclerosis.

    Science.gov (United States)

    Monteiro Junior, Renato Sobral; Dantas, Aretha; de Souza, Cíntia Pereira; da Silva, Elirez Bezerra

    2012-12-01

    Multiple sclerosis is a neurological illness that decreases motor functions. This disease can cause weakness of cardiorespiratory muscles and impaired functional capacity and quality of life. Therefore it requires preventive treatments. This study investigated the acute responses of a virtual physical training session with the Nintendo(®) (Kyoto, Japan) Wii™ on hemodynamic variables of an individual with multiple sclerosis (relapsing-remitting). A 34-year-old man with multiple sclerosis with previous experience in aerobic, strength, and functional training (2 years) was tested. His Expanded Disability Status Scale was 2.5. We compared the heart rate, blood pressure, and double product obtained at rest and during (heart rate) and after the Nintendo Wii games "Boxing" and "Sword Play." In rest, the variables were measured in the supine position. Our results showed positive hemodynamic alterations after execution of both games. The peak of heart rate was 121 beats per minute (65% of maximal heart rate) and 104 beats per minute (56% of maximal heart rate) for "Boxing" and "Sword Play," respectively. The training session with "Boxing" was able to stimulate the heart rate to achieve the recommended values for the maintenance of physical fitness in accordance with the American College of Sports Medicine guidelines. We conclude that an exercise training program with the Nintendo Wii may improve physical fitness in people with multiple sclerosis. Moreover, these activities could improve affective status and perhaps maintain the individual engaged at treatment program.

  8. Uses of stable isotopes

    International Nuclear Information System (INIS)

    Axente, Damian

    1998-01-01

    The most important fields of stable isotope use with examples are presented. These are: 1. Isotope dilution analysis: trace analysis, measurements of volumes and masses; 2. Stable isotopes as tracers: transport phenomena, environmental studies, agricultural research, authentication of products and objects, archaeometry, studies of reaction mechanisms, structure and function determination of complex biological entities, studies of metabolism, breath test for diagnostic; 3. Isotope equilibrium effects: measurement of equilibrium effects, investigation of equilibrium conditions, mechanism of drug action, study of natural processes, water cycle, temperature measurements; 4. Stable isotope for advanced nuclear reactors: uranium nitride with 15 N as nuclear fuel, 157 Gd for reactor control. In spite of some difficulties of stable isotope use, particularly related to the analytical techniques, which are slow and expensive, the number of papers reporting on this subject is steadily growing as well as the number of scientific meetings organized by International Isotope Section and IAEA, Gordon Conferences, and regional meeting in Germany, France, etc. Stable isotope application development on large scale is determined by improving their production technologies as well as those of labeled compound and the analytical techniques. (author)

  9. Hemodynamic and clinical impact of prosthesis-patient mismatch after transcatheter aortic valve implantation.

    Science.gov (United States)

    Ewe, See Hooi; Muratori, Manuela; Delgado, Victoria; Pepi, Mauro; Tamborini, Gloria; Fusini, Laura; Klautz, Robert J M; Gripari, Paola; Bax, Jeroen J; Fusari, Melissa; Schalij, Martin J; Marsan, Nina Ajmone

    2011-10-25

    This study examined the mid-term hemodynamic and clinical impact of prosthesis-patient mismatch (PPM) in patients undergoing transcatheter aortic valve implantation (TAVI) with balloon-expandable valves. PPM can be observed after aortic valve surgery. However, little is known about the incidence of PPM in patients undergoing TAVI. Echocardiography and clinical assessment were performed in 165 patients at baseline, before hospital discharge, and at 6 months after TAVI. PPM was defined as an indexed effective orifice area ≤0.85 cm(2)/m(2). Thirty patients (18.2%) showed PPM before hospital discharge. At baseline, patients with PPM had a larger body surface area (1.84 ± 0.18 m(2) vs. 1.73 ± 0.18 m(2), p = 0.003) and a greater severity of aortic stenosis (indexed valve area 0.35 ± 0.09 cm(2)/m(2) vs. 0.40 ± 0.10 cm(2)/m(2), p = 0.005) than patients without PPM. Patients with PPM demonstrated a slower and smaller reduction in mean transaortic gradient, limited left ventricular (LV) mass regression, and left atrial volume reduction over 6 months compared with patients without PPM. LV filling pressure, measured by E/e', tended to remain elevated in patients with PPM. Importantly, a higher proportion of patients with PPM did not improve in New York Heart Association functional class compared with patients without PPM (36.7% vs. 1.5%, p < 0.001), although major adverse valve-related and cardiovascular events did not differ between the 2 groups. PPM may be observed after TAVI and when present may be accompanied by less favorable changes in transvalvular hemodynamics, limited LV mass regression, persistent elevated LV filling pressure, and less improvement in clinical functional status. Copyright © 2011 American College of Cardiology Foundation. Published by Elsevier Inc. All rights reserved.

  10. Calcium stable isotope geochemistry

    Energy Technology Data Exchange (ETDEWEB)

    Gausonne, Nikolaus [Muenster Univ. (Germany). Inst. fuer Mineralogie; Schmitt, Anne-Desiree [Strasbourg Univ. (France). LHyGeS/EOST; Heuser, Alexander [Bonn Univ. (Germany). Steinmann-Inst. fuer Geologie, Mineralogie und Palaeontologie; Wombacher, Frank [Koeln Univ. (Germany). Inst. fuer Geologie und Mineralogie; Dietzel, Martin [Technische Univ. Graz (Austria). Inst. fuer Angewandte Geowissenschaften; Tipper, Edward [Cambridge Univ. (United Kingdom). Dept. of Earth Sciences; Schiller, Martin [Copenhagen Univ. (Denmark). Natural History Museum of Denmark

    2016-08-01

    This book provides an overview of the fundamentals and reference values for Ca stable isotope research, as well as current analytical methodologies including detailed instructions for sample preparation and isotope analysis. As such, it introduces readers to the different fields of application, including low-temperature mineral precipitation and biomineralisation, Earth surface processes and global cycling, high-temperature processes and cosmochemistry, and lastly human studies and biomedical applications. The current state of the art in these major areas is discussed, and open questions and possible future directions are identified. In terms of its depth and coverage, the current work extends and complements the previous reviews of Ca stable isotope geochemistry, addressing the needs of graduate students and advanced researchers who want to familiarize themselves with Ca stable isotope research.

  11. Calcium stable isotope geochemistry

    International Nuclear Information System (INIS)

    Gausonne, Nikolaus; Schmitt, Anne-Desiree; Heuser, Alexander; Wombacher, Frank; Dietzel, Martin; Tipper, Edward; Schiller, Martin

    2016-01-01

    This book provides an overview of the fundamentals and reference values for Ca stable isotope research, as well as current analytical methodologies including detailed instructions for sample preparation and isotope analysis. As such, it introduces readers to the different fields of application, including low-temperature mineral precipitation and biomineralisation, Earth surface processes and global cycling, high-temperature processes and cosmochemistry, and lastly human studies and biomedical applications. The current state of the art in these major areas is discussed, and open questions and possible future directions are identified. In terms of its depth and coverage, the current work extends and complements the previous reviews of Ca stable isotope geochemistry, addressing the needs of graduate students and advanced researchers who want to familiarize themselves with Ca stable isotope research.

  12. Stable isotope studies

    International Nuclear Information System (INIS)

    Ishida, T.

    1992-01-01

    The research has been in four general areas: (1) correlation of isotope effects with molecular forces and molecular structures, (2) correlation of zero-point energy and its isotope effects with molecular structure and molecular forces, (3) vapor pressure isotope effects, and (4) fractionation of stable isotopes. 73 refs, 38 figs, 29 tabs

  13. Interactive Stable Ray Tracing

    DEFF Research Database (Denmark)

    Dal Corso, Alessandro; Salvi, Marco; Kolb, Craig

    2017-01-01

    Interactive ray tracing applications running on commodity hardware can suffer from objectionable temporal artifacts due to a low sample count. We introduce stable ray tracing, a technique that improves temporal stability without the over-blurring and ghosting artifacts typical of temporal post-pr...

  14. The Stable Concordance Genus

    OpenAIRE

    Kearney, M. Kate

    2013-01-01

    The concordance genus of a knot is the least genus of any knot in its concordance class. Although difficult to compute, it is a useful invariant that highlights the distinction between the three-genus and four-genus. In this paper we define and discuss the stable concordance genus of a knot, which describes the behavior of the concordance genus under connected sum.

  15. Stable radiographic scanning agents

    International Nuclear Information System (INIS)

    1976-01-01

    Stable compositions which are useful in the preparation of Technetium-99m-based scintigraphic agents are discussed. They are comprised of ascorbic acid or a pharmaceutically acceptable salt or ester thereof in combination with a pertechnetate reducing agent or dissolved in oxidized pertechnetate-99m (sup(99m)TcO 4 - ) solution

  16. Some stable hydromagnetic equilibria

    Energy Technology Data Exchange (ETDEWEB)

    Johnson, J L; Oberman, C R; Kulsrud, R M; Frieman, E A [Project Matterhorn, Princeton University, Princeton, NJ (United States)

    1958-07-01

    We have been able to find and investigate the properties of equilibria which are hydromagnetically stable. These equilibria can be obtained, for example, by wrapping conductors helically around the stellarator tube. Systems with I = 3 or 4 are indicated to be optimum for stability purposes. In some cases an admixture of I = 2 fields can be advantageous for achieving equilibrium. (author)

  17. Ruptured congenital aneurysm of the right sinus of Valsalva into the right ventricle: with special reference to pathoanatomic and hemodynamic characteristics in symptomless cases.

    Science.gov (United States)

    Chen, J J; Lien, W P; Chang, F Z; Lee, Y S; Hung, C R; Chu, S S; Wu, T L

    1980-02-01

    Clinical features of 19 cases with congenital aneurysm of the right sinus of Valsalva rupturing into the right ventricular outflow region (Type 1) were analysed in relation to their pathoanatomic lesions and hemodynamic alterations. Sixteen cases were operated with one surgical death. All were catheterized together with ascending aortographic study. Rupture of the aneurysm in many cases was silent or symptomless and progressive heart failure was not quite common. Symptomatology of the patients did not seem to be related entirely to status of the pathoanatomical lesions or hemodynamic alterations. Time of the rupture, and inherent right ventricular characteristics, tolerating volume overload rather well, might be, in part, responsible for its better prognosis in some cases. However, all patients with ruptured aneurysm of the sinus of Valsalva should be treated surgically. Bacterial endocarditis is a serious complication leading to death.

  18. Advanced hemodynamic monitoring in intensive care medicine : A German web-based survey study.

    Science.gov (United States)

    Saugel, B; Reese, P C; Wagner, J Y; Buerke, M; Huber, W; Kluge, S; Prondzinsky, R

    2018-04-01

    Advanced hemodynamic monitoring is recommended in patients with complex circulatory shock. To evaluate the current attitudes and beliefs among German intensivists, regarding advanced hemodynamic monitoring, the actual hemodynamic management in clinical practice, and the barriers to using it. Web-based survey among members of the German Society of Medical Intensive Care and Emergency Medicine. Of 284 respondents, 249 (87%) agreed that further hemodynamic assessment is needed to determine the type of circulatory shock if no clear clinical diagnosis can be made. In all, 281 (99%) agreed that echocardiography is helpful for this purpose (transpulmonary thermodilution: 225 [79%]; pulmonary artery catheterization: 126 [45%]). More than 70% of respondents agreed that blood flow variables (cardiac output, stroke volume) should be measured in patients with hemodynamic instability. The parameters most respondents agreed should be assessed in a patient with hemodynamic instability were mean arterial pressure, cardiac output, and serum lactate. Echocardiography is available in 99% of ICUs (transpulmonary thermodilution: 91%; pulmonary artery catheter: 63%). The respondents stated that, in clinical practice, invasive arterial pressure measurements and serum lactate measurements are performed in more than 90% of patients with hemodynamic instability (cardiac output monitoring in about 50%; transpulmonary thermodilution in about 40%). The respondents did not feel strong barriers to the use of advanced hemodynamic monitoring in clinical practice. This survey study shows that German intensivists deem advanced hemodynamic assessment necessary for the differential diagnosis of circulatory shock and to guide therapy with fluids, vasopressors, and inotropes in ICU patients.

  19. CT myocardial perfusion imaging: current status and future perspectives.

    Science.gov (United States)

    Yang, Dong Hyun; Kim, Young-Hak

    2017-07-01

    Computed tomography myocardial perfusion (CTP) combined with coronary computed tomography angiography (CCTA) may constitute a "1-stop shop" for the noninvasive diagnosis of hemodynamically significant coronary stenosis during a single CT examination. CTP shows high diagnostic performance and provides incremental value over CCTA for the detection of hemodynamically significant coronary stenosis in patients with a high Agatston calcium score or coronary artery stents. Future studies should determine the optimal protocol and clinical value of CTP for guiding revascularization strategy and prognostication. In this article, we review the current status and future perspectives of CTP, focusing on technical considerations, clinical applications, and future research topics.

  20. 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.

  1. 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.

  2. 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

  3. 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)

  4. Hemodynamic study of cervical carotid arteries using DSA

    International Nuclear Information System (INIS)

    Kumashiro, Masayuki; Araki, Osamu; Matsunaga, Morio; Shigeyasu, Makio

    1986-01-01

    Although intravenous digital subtraction angiography (IVDSA) has been widely utilized as a means of morphological examination for the detection of intracranial or extracranial vascular lesions, it has thus for contributed little to quantitative assessment in hemodynamics. In the present study, a fundamental analysis of the hemodynamics on the cervical carotid artery was performed with a relative perfusion efficiency (Rath et al., 1979). This was not related to the measurement of time, such as the mean transit time, but was based on Sapirstein's principle. After the intravenous administration of the contrast material, dynamic DSA was performed using our equipment, Shimadzu DAR-100. After setting the region of interest in common carotid arteries on DSA images by means of a microdensitometer (Sakura PDS-15) combined with a computer (NEC ACOS-460), time-density curves were obtained on both sides. Thereafter, the RPE was calculated as a ratio of two integrals from the zero time to the earlier peak time of the time-density curves with respect to the time. The flow model with the hydro-dynamic system was used to detect the relationship between the RPEs and the ratios of the actual flows in the system. The results of this experiment showed a high correlation between the RPEs and the flows (r = 0.85, p < 0.001). In normal subjects (n = 28), the mean of the RPEs was 1.07 ± 0.27 (S.D.). The RPEs showed significantly lower values in the 5 patients with severe stenosis of the internal carotid artery (0.76 ± 0.15, p < 0.02), as well as even more significantly lower values in the 9 patients with a complete occlusion of the internal carotid artery (0.64 ± 0.19, p < 0.001). The RPE measurement with IVDSA has been shown to be useful for recognizing the cervical hemodynamic changes in patients with occlusive cervicovascular disease. (author)

  5. Separating genetic and hemodynamic defects in neuropilin 1 knockout embryos.

    Science.gov (United States)

    Jones, Elizabeth A V; Yuan, Li; Breant, Christine; Watts, Ryan J; Eichmann, Anne

    2008-08-01

    Targeted inactivation of genes involved in murine cardiovascular development frequently leads to abnormalities in blood flow. As blood fluid dynamics play a crucial role in shaping vessel morphology, the presence of flow defects generally prohibits the precise assignment of the role of the mutated gene product in the vasculature. In this study, we show how to distinguish between genetic defects caused by targeted inactivation of the neuropilin 1 (Nrp1) receptor and hemodynamic defects occurring in homozygous knockout embryos. Our analysis of a Nrp1 null allele bred onto a C57BL/6 background shows that vessel remodeling defects occur concomitantly with the onset of blood flow and cause death of homozygous mutants at E10.5. Using mouse embryo culture, we establish that hemodynamic defects are already present at E8.5 and continuous circulation is never established in homozygous mutants. The geometry of yolk sac blood vessels is altered and remodeling into yolk sac arteries and veins does not occur. To separate flow-induced deficiencies from those caused by the Nrp1 mutation, we arrested blood flow in cultured wild-type and mutant embryos and followed their vascular development. We find that loss of Nrp1 function rather than flow induces the altered geometry of the capillary plexus. Endothelial cell migration, but not replication, is altered in Nrp1 mutants. Gene expression analysis of endothelial cells isolated from freshly dissected wild-type and mutants and after culture in no-flow conditions showed down-regulation of the arterial marker genes connexin 40 and ephrin B2 related to the loss of Nrp1 function. This method allows genetic defects caused by loss-of-function of a gene important for cardiovascular development to be isolated even in the presence of hemodynamic defects.

  6. Effect of dialysate temperature on hemodynamic stability among hemodialysis patients

    International Nuclear Information System (INIS)

    Azar, Ahmad Taher

    2009-01-01

    Cooling the dialysate below 36.5 degree C is an important factor that contributes to hemody-namic stability in patients during hemodialysis (HD). In this study, the effect of dialysate tempe-rature on hemodynamic stability, patients' perception of dialysis discomfort and post dialysis fatigue were assessed in a group of patients on HD. A total of 50 patients, all of whom were on 3-times-perweek dialysis regimen, were studied. Patients were assessed during six dialysis sessions; in three sessions, the dialysate temperature was normal (37 degree C) and in three other sessions, the dialysate temperature was low (35 degree C). Specific scale questionnaires were used in each dialysis session, to evaluate the symptoms during the dialysis procedure as well as post-dialysis fatigue, and respective scores were noted. The results showed that usage of low dialysate temperature was associated with the following: higher post dialysis systolic blood pressure (P< 0.05) and lower post dialysis heart rate (P<0.01), with similar ultrafiltration rates, better intra-dialysis symptoms score and post-dialysis fatigue scores (P< 0.001, and P<0.001, respectively), shorter post-dialysis fatigue period (P<0.001) as well as higher urea removal (P< 00001) and Kt/V (P< 0.0001). Patients' perceptions were measured by a questionnaire, which showed that 76% of them felt more energetic after dialysis with cool dialysate and requested to be always dialyzed with cool dialysate. Low temperature dialysate is particularly beneficial for highly symptomatic patients, improves tolerance to dialysis in hypotensive patients and helps increase ultrafiltration while maintaining hemodynamic stability during and after dialysis. (author)

  7. Diffuse optical measurements of head and neck tumor hemodynamics for early prediction of radiation therapy (Conference Presentation)

    Science.gov (United States)

    Dong, Lixin; Kudrimoti, Mahesh; Irwin, Daniel; Chen, Li; Shang, Yu; Li, Xingzhe; Stevens, Scott D.; Shelton, Brent J.; Yu, Guoqiang

    2016-03-01

    Radiation therapy is a principal modality for head and neck cancers and its efficacy depends on tumor hemodynamics. Our laboratory developed a hybrid diffuse optical instrument allowing for simultaneous measurements of tumor blood flow and oxygenation. In this study, the clinically involved cervical lymph node was monitored by the hybrid instrument once a week over the treatment period of seven weeks. Based on treatment outcomes within one year, patients were classified into a complete response group (CR) and an incomplete response group (IR) with remote metastasis and/or local recurrence. A linear mixed models was used to compare tumor hemodynamic responses to the treatment between the two groups. Interestingly, we found that human papilloma virus (HPV-16) status largely affected tumor hemodynamic responses. For HPV-16 negative tumors, significant differences in blood flow index (BFI, p = 0.007) and reduced scattering coefficient (μs', p = 0.0005) were observed between the two groups; IR tumors exhibited higher μs' values and a continuous increase in BFI over the treatment period. For HPV-16 positive tumors, oxygenated hemoglobin concentration ([HbO2]) and blood oxygen saturation (StO2) were significant different (p = 0.003 and 0.01, respectively); IR group showed lower [HbO2] and StO2. Our results imply HPV-16 negative tumors with higher density of vasculature (μs') and higher blood flow show poor responses to radiotherapy and HPV-16 positive tumors with lower tissue oxygenation level (lower StO2 and [HbO2]) exhibit poor treatment outcomes. Our diffuse optical measurements show the great potential for early prediction of radiotherapy in head and neck cancers.

  8. Comparison of hemodynamic and nutritional parameters between older persons practicing regular physical activity, nonsmokers and ex-smokers

    Directory of Open Access Journals (Sweden)

    Rebelatto Marcelo N

    2010-11-01

    Full Text Available Abstract Background Sedentary lifestyle combined with smoking, contributes to the development of a set of chronic diseases and to accelerating the course of aging. The aim of the study was to compare the hemodynamic and nutritional parameters between elderly persons practicing regular physical activity, nonsmokers and ex-smokers. Methods The sample was comprised of 40 elderly people practicing regular physical activity for 12 months, divided into a Nonsmoker Group and an Ex-smoker Group. During a year four trimestrial evaluations were performed, in which the hemodynamic (blood pressure, heart rate- HR and VO2 and nutritional status (measured by body mass index data were collected. The paired t-test and t-test for independent samples were applied in the intragroup and intergroup analysis, respectively. Results The mean age of the groups was 68.35 years, with the majority of individuals in the Nonsmoker Group being women (n = 15 and the Ex-smoker Group composed of men (n = 11. In both groups the variables studied were within the limits of normality for the age. HR was diminished in the Nonsmoker Group in comparison with the Ex-smoker Group (p = 0.045 between the first and last evaluation. In the intragroup analysis it was verified that after one year of exercise, there was significant reduction in the HR in the Nonsmoker Group (p = 0.002 and a significant increase in VO2 for the Ex-smoker Group (p = 0.010. There are no significant differences between the hemodynamic and nutritional conditions in both groups. Conclusion In elderly persons practicing regular physical activity, it was observed that the studied variables were maintained over the course of a year, and there was no association with the history of smoking, except for HR and VO2.

  9. 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.

  10. Effects of Dietary Nitrates on Systemic and Cerebrovascular Hemodynamics

    Directory of Open Access Journals (Sweden)

    Vernon Bond

    2013-01-01

    Full Text Available 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.

  11. 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.

  12. Automated analysis of plethysmograms for functional studies of hemodynamics

    Science.gov (United States)

    Zatrudina, R. Sh.; Isupov, I. B.; Gribkov, V. Yu.

    2018-04-01

    The most promising method for the quantitative determination of cardiovascular tone indicators and of cerebral hemodynamics indicators is the method of impedance plethysmography. The accurate determination of these indicators requires the correct identification of the characteristic points in the thoracic impedance plethysmogram and the cranial impedance plethysmogram respectively. An algorithm for automatic analysis of these plethysmogram is presented. The algorithm is based on the hard temporal relationships between the phases of the cardiac cycle and the characteristic points of the plethysmogram. The proposed algorithm does not require estimation of initial data and selection of processing parameters. Use of the method on healthy subjects showed a very low detection error of characteristic points.

  13. Portal hemodynamics in chronic portal-systemic encephalopathy

    International Nuclear Information System (INIS)

    Takashi, Motohide; Igarashi, Masahiko; Hino, Shinichi; Takayasu, Kenichi; Goto, Nobuaki; Musha, Hirotaka; Ohnishi, Kunihiko; Okuda, Kunio

    1985-01-01

    A portal hemodynamic study was made in 7 consecutive patients with chronic portal-systemic encephalopathy by percutaneous transhepatic catheterization of the portal vein and injecting contrast medium into the superior mesenteric vein or by superior mesenteric arterial portography in comparison with patients without encephalopathy studied by percutaneous catheterization of these veins. It is suggested that chronic portal-systemic encephalopathy is a result of a large collateral route shunting a large proportion of the superior mesenteric venous blood into systemic circulation, and that development of such collaterals precludes formation of large esophageal varices. (Auth.)

  14. Hemodynamic mechanisms underlying the incomplete tolerance to caffeine's pressor effects.

    Science.gov (United States)

    Farag, Noha H; Vincent, Andrea S; McKey, Barbara S; Whitsett, Thomas L; Lovallo, William R

    2005-06-01

    Blood pressure (BP) and cardiovascular hemodynamics were assessed at baseline and after caffeine administration in a 4-week, placebo-controlled, double-blind, randomized, crossover trial of caffeine tolerance formation. Half of the subjects developed tolerance to the pressor effect of caffeine, whereas the other half continued to show increases in BP after caffeine ingestion (F = 16.7, p <0.0001). In the subjects who did not develop tolerance, peripheral resistance increased incrementally as the daily dose of caffeine increased (F = 2.8, p = 0.05).

  15. 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.

  16. 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

  17. Stable isotope analysis

    International Nuclear Information System (INIS)

    Tibari, Elghali; Taous, Fouad; Marah, Hamid

    2014-01-01

    This report presents results related to stable isotopes analysis carried out at the CNESTEN DASTE in Rabat (Morocco), on behalf of Senegal. These analyzes cover 127 samples. These results demonstrate that Oxygen-18 and Deuterium in water analysis were performed by infrared Laser spectroscopy using a LGR / DLT-100 with Autosampler. Also, the results are expressed in δ values (‰) relative to V-SMOW to ± 0.3 ‰ for oxygen-18 and ± 1 ‰ for deuterium.

  18. Influence of lateral decubitus positioning after combined use of hyperbaric and hypobaric ropivacaine on hemodynamic characteristics in spinal anesthesia for caesarean section.

    Science.gov (United States)

    Quan, Zhe-Feng; He, Hai-Li; Tian, Ming; Chi, Ping; Li, Xin

    2014-01-01

    Positioning of the patient during and after surgery can have significant implications on recovery. Therefore, the purpose of the present study was to determine the influence of placing patients in a lateral decubitus position for 15 min after combined use of hyperbaric and hypobaric ropivacaine and assess hemodynamic characteristics during spinal anesthesia for caesarean section. One hundred-forty patients undergoing elective cesarean delivery with combined use of hyperbaric and hypobaric ropivacaine were included in the present study. Patients meeting inclusion criteria (134) were randomly allocated into Group A: immediately turned to the supine position after induction of spinal anesthesia (n = 67) or Group B: maintained in a lateral decubitus position for 15 min before being turned to the supine position (n = 67). Primary endpoints of the study were to compare hemodynamic characteristics and sensory blockade levels in the two groups, while a secondary endpoint was to observe the incidence of complications. Both groups showed similar effects of the combined anesthetic treatment. Incidence of hypotension (43% vs 18%, P = 0.001), systolic AP hyperbaric and hypobaric ropivacaine had satisfactory anesthetic effects and a more stable hemodynamic characteristic than either drug used alone. Maintaining the patient in a lateral decubitus position for 15 min can significantly decrease the incidence of hypotension.

  19. Forensic Stable Isotope Biogeochemistry

    Science.gov (United States)

    Cerling, Thure E.; Barnette, Janet E.; Bowen, Gabriel J.; Chesson, Lesley A.; Ehleringer, James R.; Remien, Christopher H.; Shea, Patrick; Tipple, Brett J.; West, Jason B.

    2016-06-01

    Stable isotopes are being used for forensic science studies, with applications to both natural and manufactured products. In this review we discuss how scientific evidence can be used in the legal context and where the scientific progress of hypothesis revisions can be in tension with the legal expectations of widely used methods for measurements. Although this review is written in the context of US law, many of the considerations of scientific reproducibility and acceptance of relevant scientific data span other legal systems that might apply different legal principles and therefore reach different conclusions. Stable isotopes are used in legal situations for comparing samples for authenticity or evidentiary considerations, in understanding trade patterns of illegal materials, and in understanding the origins of unknown decedents. Isotope evidence is particularly useful when considered in the broad framework of physiochemical processes and in recognizing regional to global patterns found in many materials, including foods and food products, drugs, and humans. Stable isotopes considered in the larger spatial context add an important dimension to forensic science.

  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. 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.

  2. Brain Electrodynamic and Hemodynamic Signatures Against Fatigue During Driving

    Directory of Open Access Journals (Sweden)

    Chun-Hsiang Chuang

    2018-03-01

    Full Text Available Fatigue is likely to be gradually cumulated in a prolonged and attention-demanding task that may adversely affect task performance. To address the brain dynamics during a driving task, this study recruited 16 subjects to participate in an event-related lane-departure driving experiment. Each subject was instructed to maintain attention and task performance throughout an hour-long driving experiment. The subjects' brain electrodynamics and hemodynamics were simultaneously recorded via 32-channel electroencephalography (EEG and 8-source/16-detector functional near-infrared spectroscopy (fNIRS. The behavior performance demonstrated that all subjects were able to promptly respond to lane-deviation events, even if the sign of fatigue arose in the brain, which suggests that the subjects were fighting fatigue during the driving experiment. The EEG event-related analysis showed strengthening alpha suppression in the occipital cortex, a common brain region of fatigue. Furthermore, we noted increasing oxygenated hemoglobin (HbO of the brain to fight driving fatigue in the frontal cortex, primary motor cortex, parieto-occipital cortex and supplementary motor area. In conclusion, the increasing neural activity and cortical activations were aimed at maintaining driving performance when fatigue emerged. The electrodynamic and hemodynamic signatures of fatigue fighting contribute to our understanding of the brain dynamics of driving fatigue and address driving safety issues through the maintenance of attention and behavioral performance.

  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. 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.

  5. Study of retrobulbar hemodynamics in diabetes via color doppler ultrasound

    Directory of Open Access Journals (Sweden)

    Wei Chen

    2014-09-01

    Full Text Available AIM: To explore the changes of retrobulbar hemodynamics in diabetes via color doppler ultrasound. METHODS: Totally 80 patients(160 eyeswith eye diseases in type 2 diabetes from June 2010 to May 2013 in our hospital were enrolled as research group. By fundus photography and direct ophthalmoscopy, patients were assigned to diabetes without retinopathy group(DNR subgroup, non-proliferative diabetic retinopathy group(NPDR subgroupand proliferative diabetic retinopathy group(PDR subgroup. Of 60 healthy patients(120 eyesover the same period were chosen as control group. The doppler parameters of central retinal artery(CRA, posterior ciliary artery(PCAand ophthalmic artery(OAwere measured.RESULTS: There were significant differences on circulatory parameters of CRA, PCA and OA between both groups(PPPCONCLUSION: The monitoring of retinal blood flow and analysis of blood spectrum morphology via color doppler ultrasound can effectively evaluate the degree of diabetic retinopathy lesions, especially before DR vascular disease. Early detection can reveal the hemodynamic change pattern of DR, facilitating the prevention of diabetic eye complications and improvement of the quality of life.

  6. 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.

  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. Hemodynamic transition driven by stent porosity in sidewall aneurysms.

    Science.gov (United States)

    Bouillot, Pierre; Brina, Olivier; Ouared, Rafik; Lovblad, Karl-Olof; Farhat, Mohamed; Pereira, Vitor Mendes

    2015-05-01

    The healing process of intracranial aneurysms (IAs) treated with flow diverter stents (FDSs) depends on the IA flow modifications and on the epithelization process over the neck. In sidewall IA models with straight parent artery, two main hemodynamic regimes with different flow patterns and IA flow magnitude were broadly observed for unstented and high porosity stented IA on one side, and low porosity stented IA on the other side. The hemodynamic transition between these two regimes is potentially involved in thrombosis formation. In the present study, CFD simulations and multi-time lag (MTL) particle imaging velocimetry (PIV) measurements were combined to investigate the physical nature of this transition. Measurable velocity fields and non-measurable shear stress and pressure fields were assessed experimentally and numerically in the aneurysm volume in the presence of stents with various porosities. The two main regimes observed in both PIV and CFD showed typical flow features of shear and pressure driven regimes. In particular, the waveform of the averaged IA velocities was matching both the shear stress waveform at IA neck or the pressure gradient waveform in parent artery. Moreover, the transition between the two regimes was controlled by stent porosity: a decrease of stent porosity leads to an increase (decrease) of pressure differential (shear stress) through IA neck. Finally, a good PIV-CFD agreement was found except in transitional regimes and low motion eddies due to small mismatch of PIV-CFD running conditions. Copyright © 2015 Elsevier Ltd. All rights reserved.

  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. 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

  11. Influence of an acetate- and a lactate-based balanced infusion solution on acid base physiology and hemodynamics: an observational pilot study.

    Science.gov (United States)

    Hofmann-Kiefer, Klaus F; Chappell, Daniel; Kammerer, Tobias; Jacob, Matthias; Paptistella, Michaela; Conzen, Peter; Rehm, Markus

    2012-07-06

    The current pilot study compares the impact of an intravenous infusion of Ringer's lactate to an acetate-based solution with regard to acid-base balance. The study design included the variables of the Stewart approach and focused on the effective strong ion difference. Because adverse hemodynamic effects have been reported when using acetate buffered solutions in hemodialysis, hemodynamics were also evaluated. Twenty-four women who had undergone abdominal gynecologic surgery and who had received either Ringer's lactate (Strong Ion Difference 28 mmol/L; n = 12) or an acetate-based solution (Strong Ion Difference 36.8 mmol/L; n = 12) according to an established clinical protocol and its precursor were included in the investigation. After induction of general anesthesia, a set of acid-base variables, hemodynamic values and serum electrolytes was measured three times during the next 120 minutes. Patients received a mean dose of 4,054 ± 450 ml of either one or the other of the solutions. In terms of mean arterial blood pressure and norepinephrine requirements there were no differences to observe between the study groups. pH and serum HCO3- concentration decreased slightly but significantly only with Ringer's lactate. In addition, the acetate-based solution kept the plasma effective strong ion difference more stable than Ringer's lactate. Both of the solutions provided hemodynamic stability. Concerning consistency of acid base parameters none of the solutions seemed to be inferior, either. Whether the slight advantages observed for the acetate-buffered solution in terms of stability of pH and plasma HCO3- are clinically relevant, needs to be investigated in a larger randomized controlled trial.

  12. Hemodynamic control of in patients with concomitant hypertensive disease during brain aneurysm clipping

    OpenAIRE

    Dzyuba, D.O.; Melnik, A.F.; Yavorsky, F.A.

    2018-01-01

    The article describes the state of the problem of hemodynamic control during brain aneurysm clipping in concomitant hypertensive disease. Author studies hemodynamic control by using magnesia therapy with the addition of clonidine solution and infusion of urapidil solution. Based on the results of the study, the advantages of urapidil infusion are given.

  13. 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...

  14. 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...

  15. 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

  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. Encephalic hemodynamic phases in subarachnoid hemorrhage: how to improve the protective effect in patient prognoses

    Directory of Open Access Journals (Sweden)

    Marcelo de Lima Oliveira

    2015-01-01

    Full Text Available Subarachnoid hemorrhage is frequently associated with poor prognoses. Three different hemodynamic phases were identified during subarachnoid hemorrhage: oligemia, hyperemia, and vasospasm. Each phase is associated with brain metabolic changes. In this review, we correlated the hemodynamic phases with brain metabolism and potential treatment options in the hopes of improving patient prognoses.

  18. Fermented ginseng, GBCK25, ameliorates hemodynamic function on experimentally induced myocardial injury

    Directory of Open Access Journals (Sweden)

    Adithan Aravinthan

    2016-10-01

    Full Text Available In the present study, we investigated whether treatment with GBCK25 facilitated the recovery of hemodynamic parameters, left ventricle systolic pressure, left ventricular developed pressure, and electrocardiographic changes. GBCK25 significantly prevented the decrease in hemodynamic parameters and ameliorated the electrocardiographic abnormality. These results indicate that GBCK25 has distinct cardioprotective effects in rat heart.

  19. Short-term vascular hemodynamic responses to isometric exercise in young adults and in the elderly

    NARCIS (Netherlands)

    Hartog, R. (Renee); D. Bolignano (Davide); E.J.G. Sijbrands (Eric); Pucci, G. (Giacomo); F.U.S. Mattace Raso (Francesco)

    2018-01-01

    textabstractBackground: Vascular aging is known to induce progressive stiffening of the large elastic arteries, altering vascular hemodynamics under both rest and stress conditions. In this study, we aimed to investigate changes in vascular hemodynamics in response to isometric handgrip exercise

  20. Some hemodynamic changes in the organism following exposure to X-and gamma-radiation

    Energy Technology Data Exchange (ETDEWEB)

    Bliznakov, V; Mikhailov, A [Meditsinska Akademiya, Sofia (Bulgaria). Nauchen Inst. po Rentgenologiya i Radiobiologiya

    1982-01-01

    The hemodynamic response to dosed exercise of 705 physicians, nurses, roentgen technicians and hospital attendants, working with X-ray diagnostic and therapeutic devices, was studied. The doses received on professional irradiation proved to be below the threshold ones. A significantly increased incidence was recorded in cases of atonic hemodynamic response, mainly in medical workers, employed in X-ray departments.

  1. 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.

  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. Stable isotopes in Lithuanian bioarcheological material

    Science.gov (United States)

    Skipityte, Raminta; Jankauskas, Rimantas; Remeikis, Vidmantas

    2015-04-01

    Schutkowski. "Diet and social status during the La Tène period in Bohemia: carbon and nitrogen stable isotope analysis of bone collagen from Kutná Hora-Karlov and Radovesice." Journal of Anthropological Archaeology 24.2 (2005): 135-147. Schutkowski, Holger, et al. "Diet, status and decomposition at Weingarten: trace element and isotope analyses on early mediaeval skeletal material." Journal of Archaeological Science 26.6 (1999): 675-685. Zernitskaya, Valentina, et al. "Vegetation pattern and sedimentation changes in the context of the Lateglacial climatic events: Case study of Staroje Lake (Eastern Belarus)." Quaternary International (2014).

  4. Quantitative assessment of cerebral hemodynamic parameters by QUASAR arterial spin labeling in Alzheimer's disease and cognitively normal Elderly adults at 3-tesla.

    Science.gov (United States)

    Mak, Henry K F; Chan, Queenie; Zhang, Zhipeng; Petersen, Esben T; Qiu, Deqiang; Zhang, Linda; Yau, Kelvin K W; Chu, Leung-Wing; Golay, Xavier

    2012-01-01

    QUASAR arterial spin labeling (ASL) was used to investigate the role of vascular impairment in Alzheimer's disease (AD). We hypothesized that the hemodynamic parameters monitoring cerebrovascular integrity, i.e., cerebral blood flow (CBF), arterial blood volume (aBV), and arterial transit time (aTT), would be affected. 13 AD patients and 15 healthy control (HC) subjects underwent 3T MRI scanning. Two separate blood flow acquisitions were obtained with 1 slice overlap for whole brain coverage. CBF, aBV, and aTT maps were calculated using in-house software. Preprocessing and statistical analyses were performed on SPM5. Region-of-interest (ROI) studies of ten selected cerebral regions were also conducted. There were significant differences in mini mental status exam (MMSE) (AD: 16.3 ± 4.55, HC: 28.5 ± 2.00) and Alzheimer's disease assessment scale-cognitive subscale (ADAS-cog) scores (AD: 25.25 ± 9.64, HC: 5.51 ± 2.62) between the 2 groups (p QUASAR ASL, we found patterns of regional hemodynamic impairment typical of moderate AD, suggesting underlying vascular abnormality. As potential biomarkers, these hemodynamic parameters could differentiate patients from volunteers, and possibly indicate the conversion from healthy aging to mild cognitive impairment to AD.

  5. Studies on the Hemodynamic Change in Cirrhosis of the Liver

    International Nuclear Information System (INIS)

    Kim, Jung Il; Lee, Jung Sang; Koh, Chang Soon

    1970-01-01

    Cardiac output, plasma volume and renal plasma flow were determined to evaluate hemodynamic changes in 29 patients with cirrhosis of the liver. The results obtained were as follows. 1) The mean plasma volume was 3793±895 ml and it was significantly higher than the normal controls. The mean blood volume (5266±1222 ml) and blood volume per kg body weight (95.7±23.41 ml) were also increased significantly. The mean plasma volume per kg body weight (69.1±19.1 ml) showed increased tendency and the mean difference between blood volume and plasma volume per kg body weight (26.4±7.05 ml) was in lower limit of normal range. 2) The mean cardiac output was 7708±2652 ml/min and it was significantly increased. The mean cardiac index (4924±1998 ml/min/M 2 ), stroke volume (96.2±34.2 ml/beat), stroke index (62.3±27.34 ml/beat/M 2 ) and fractional cardiac index (1.54±0.577) were also increased significantly. The mean total peripheral resistance was 1664±753.8 dynes sec cm -5 M 2 and it was significantly lower than the normal controls. 3) The mean renal plasma flow was 537±146.8 ml/min/1.73M 2 and it was normal to decreased tendency. The mean endogenous creatinine clearance (66.7±23.0 ml/min/1.73M 2 ) was significantly decreased. Filtration fraction was variable, but it was slightly lower than normal in most cases. The mean renal fraction of cardiac output (11.4±6.27%) was relatively decreased. 4) Although renal plasma flow was normal or decreased in general, it was definitely diminished in patients with creatinine clearance less than 60 ml/min/1.73M 2 , resistant ascites, and signs of azotemia (elevated BUN and serum creatinine). 5) Diminished glomerular filtration rate with low filtration fraction and decreased renal fraction of cardiac output observed strongly supported increased renal afferent arteriolar resistance. 6) Renal circulatory impairment preceded azotemia or oroliguria in cirrhosis. 7) Clinical findings and liver function were not correlated with

  6. Estimating Hemodynamic Responses to the Wingate Test Using Thoracic Impedance

    Directory of Open Access Journals (Sweden)

    Todd A. Astorino, Curtis Bovee, Ashley DeBoe

    2015-12-01

    Full Text Available Techniques including direct Fick and Doppler echocardiography are frequently used to assess hemodynamic responses to exercise. Thoracic impedance has been shown to be a noninvasive alternative to these methods for assessing these responses during graded exercise to exhaustion, yet its feasibility during supramaximal bouts of exercise is relatively unknown. We used thoracic impedance to estimate stroke volume (SV and cardiac output (CO during the Wingate test (WAnT and compared these values to those from graded exercise testing (GXT. Active men (n = 9 and women (n = 7 (mean age = 24.8 ± 5.9 yr completed two Wingate tests and two graded exercise tests on a cycle ergometer. During exercise, heart rate (HR, SV, and CO were continuously estimated using thoracic impedance. Repeated measures analysis of variance was used to identify potential differences in hemodynamic responses across protocols. Results: Maximal SV (138.6 ± 37.4 mL vs. 135.6 ± 26.9 mL and CO (24.5 ± 6.1 L·min-1 vs. 23.7 ± 5.1 L·min-1 were similar (p > 0.05 between repeated Wingate tests. Mean maximal HR was higher (p < 0.01 for GXT (185 ± 7 b·min-1 versus WAnT (177 ± 11 b·min-1, and mean SV was higher in response to WAnT (137.1 ± 32.1 mL versus GXT (123.0 ± 32.0 mL, leading to similar maximal cardiac output between WAnT and GXT (23.9 ± 5.6 L·min-1 vs. 22.5 ± 6.0 L·min-1. Our data show no difference in hemodynamic responses in response to repeated administrations of the Wingate test. In addition, the Wingate test elicits similar cardiac output compared to progressive cycling to VO2max.

  7. Divergent effects of laughter and mental stress on arterial stiffness and central hemodynamics.

    Science.gov (United States)

    Vlachopoulos, Charalambos; Xaplanteris, Panagiotis; Alexopoulos, Nikolaos; Aznaouridis, Konstantinos; Vasiliadou, Carmen; Baou, Katerina; Stefanadi, Elli; Stefanadis, Christodoulos

    2009-05-01

    To investigate the effect of laughter and mental stress on arterial stiffness and central hemodynamics. Arterial stiffness and wave reflections are independent predictors of cardiovascular risk. Chronic psychological stress is an independent risk factor for cardiovascular events, whereas acute stress deteriorates vascular function. Eighteen healthy individuals were studied on three occasions, according to a randomized, single-blind, crossover, sham procedure-controlled design. The effects of viewing a 30-minute segment of two films inducing laughter or stress were assessed. Carotid-femoral pulse wave velocity was used as an index of arterial stiffness; augmentation index was used as a measure of wave reflections. Laughter decreased pulse wave velocity (by 0.30 m/sec, p = .01), and augmentation index (by 2.72%, p = .05). Conversely, stress increased pulse wave velocity (by 0.29 m/sec, p = .05) and augmentation index (by 5.1%, p = .005). Laughter decreased cortisol levels by 1.67 microg/dl (p = .02), soluble P-selectin by 26 ng/ml (p = .02) and marginally von Willebrand factor (by 2.4%, p = .07) and increased total oxidative status (by 61 micromol/L, p laughter) and negative (stress) behavioral interventions have divergent acute effects on arterial stiffness and wave reflections. These findings have important clinical implications extending the spectrum of lifestyle modifications that can ameliorate arterial function.

  8. Efficient hemodynamic event detection utilizing relational databases and wavelet analysis

    Science.gov (United States)

    Saeed, M.; Mark, R. G.

    2001-01-01

    Development of a temporal query framework for time-oriented medical databases has hitherto been a challenging problem. We describe a novel method for the detection of hemodynamic events in multiparameter trends utilizing wavelet coefficients in a MySQL relational database. Storage of the wavelet coefficients allowed for a compact representation of the trends, and provided robust descriptors for the dynamics of the parameter time series. A data model was developed to allow for simplified queries along several dimensions and time scales. Of particular importance, the data model and wavelet framework allowed for queries to be processed with minimal table-join operations. A web-based search engine was developed to allow for user-defined queries. Typical queries required between 0.01 and 0.02 seconds, with at least two orders of magnitude improvement in speed over conventional queries. This powerful and innovative structure will facilitate research on large-scale time-oriented medical databases.

  9. 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

  10. Milrinone use for hemodynamic instability in patent ductus arteriosus ligation.

    Science.gov (United States)

    Halliday, Matthew; Kavarana, Minoo; Ebeling, Myla; Kiger, James

    2017-03-01

    Determine if prophylactic milrinone improves cardiovascular or long-term clinical outcomes in preterm neonates who receive surgical patent ductus arteriosus (PDA) ligation. Retrospective review of 45 infants over a 4-year period that received a PDA ligation at one institution. Data were collected on morbidity and mortality outcomes for all infants as well as milrinone therapy perioperatively. Of the 45 infants that were studied 15 received milrinone in the perioperative period of PDA ligation and the remaining 30 infants did not receive milrinone. The use of milrinone showed no statistically significant improvement in acute markers of hemodynamic stability. There was also no statistically significant difference in morbidity and mortality outcomes in milrinone group compared to the non-milrinone group. Prophylactic milrinone use for premature infants following PDA ligation does not show a significant cardiovascular or long-term clinical benefit.

  11. Hemodynamic signals of mixed messages during a social exchange.

    Science.gov (United States)

    Zucker, Nancy L; Green, Steven; Morris, James P; Kragel, Philip; Pelphrey, Kevin A; Bulik, Cynthia M; LaBar, Kevin S

    2011-06-22

    This study used functional magnetic resonance imaging to characterize hemodynamic activation patterns recruited when the participants viewed mixed social communicative messages during a common interpersonal exchange. Mixed messages were defined as conflicting sequences of biological motion and facial affect signals that are unexpected within a particular social context (e.g. observing the reception of a gift). Across four social vignettes, valenced facial expressions were crossed with rejecting and accepting gestures in a virtual avatar responding to presentation of a gift from the participant. The results indicate that conflicting facial affect and gesture activated superior temporal sulcus, a region implicated in expectancy violations, as well as inferior frontal gyrus and putamen. Scenarios conveying rejection differentially activated the insula and putamen, regions implicated in embodied cognition, and motivated learning, as well as frontoparietal cortex. Characterizing how meaning is inferred from integration of conflicting nonverbal communicative cues is essential to understand nuances and complexities of human exchange.

  12. 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.

  13. [Damage control in trauma patients with hemodynamic instability].

    Science.gov (United States)

    Müller, Thorben; Doll, Dietrich; Kliebe, Frank; Ruchholtz, Steffen; Kühne, Christian

    2010-10-01

    The term "Damage-control" is borrowed from naval terminology. It means the initial control of a damaged ship. Because of the lethal triad in multiple injured patients the classical concept of definitive surgically therapy in the acute phase of the injury has a high rate of complications such as exsanguination, sepsis, heart failure and multiple organ failure. The core idea of the damage control concept was to minimize the additional trauma by surgical operations in these critical patients in the first phase. This means temporary control of a hemorrhage and measures for stopping abdominal contamination. After 24 - 48 hours in the intensive care unit and correction of physiological disturbances further interventions are performed for definitively treatment of the injuries. Summarized, the damage control strategy comprises an abbreviated operation, intensive care unit resuscitation, and a return to the operating room for the definitive operation after hemodynamic stabilisation of the patient. © Georg Thieme Verlag Stuttgart · New York.

  14. Theory of stable allocations

    Directory of Open Access Journals (Sweden)

    Pantelić Svetlana

    2014-01-01

    Full Text Available The Swedish Royal Academy awarded the 2012 Nobel Prize in Economics to Lloyd Shapley and Alvin Roth, for the theory of stable allocations and the practice of market design. These two American researchers worked independently from each other, combining basic theory and empirical investigations. Through their experiments and practical design they generated a flourishing field of research and improved the performance of many markets. Born in 1923 in Cambridge, Massachusetts, Shapley defended his doctoral thesis at Princeton University in 1953. For many years he worked at RAND, and for more than thirty years he was a professor at UCLA University. He published numerous scientific papers, either by himself or in cooperation with other economists.

  15. 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

  16. 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.

  17. 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.

  18. 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).

  19. 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.

  20. Hemodynamic parameters change earlier than tissue oxygen tension in hemorrhage.

    Science.gov (United States)

    Pestel, Gunther J; Fukui, Kimiko; Kimberger, Oliver; Hager, Helmut; Kurz, Andrea; Hiltebrand, Luzius B

    2010-05-15

    Untreated hypovolemia results in impaired outcome. This study tests our hypothesis whether general hemodynamic parameters detect acute blood loss earlier than monitoring parameters of regional tissue beds. Eight pigs (23-25 kg) were anesthetized and mechanically ventilated. A pulmonary artery catheter and an arterial catheter were inserted. Tissue oxygen tension was measured with Clark-type electrodes in the jejunal and colonic wall, in the liver, and subcutaneously. Jejunal microcirculation was assessed by laser Doppler flowmetry (LDF). Intravascular volume was optimized using difference in pulse pressure (dPP) to keep dPP below 13%. Sixty minutes after preparation, baseline measurements were taken. At first, 5% of total blood volume was withdrawn, followed by another 5% increment, and then in 10% increments until death. After withdrawal of 5% of estimated blood volume, dPP increased from 6.1% +/- 3.0% to 20.8% +/- 2.7% (P < 0.01). Mean arterial pressure (MAP), mean pulmonary artery pressure (PAP) and pulmonary artery occlusion pressure (PAOP) decreased with a blood loss of 10% (P < 0.01). Cardiac output (CO) changed after a blood loss of 20% (P < 0.05). Tissue oxygen tension in central organs, and blood flow in the jejunal muscularis decreased (P < 0.05) after a blood loss of 20%. Tissue oxygen tension in the skin, and jejunal mucosa blood flow decreased (P < 0.05) after a blood loss of 40% and 50%, respectively. In this hemorrhagic pig model systemic hemodynamic parameters were more sensitive to detect acute hypovolemia than tissue oxygen tension measurements or jejunal LDF measurements. Acute blood loss was detected first by dPP. Copyright (c) 2010 Elsevier Inc. All rights reserved.

  1. 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.

  2. Arterial stiffness, central hemodynamics, and cardiovascular risk in hypertension

    Science.gov (United States)

    Palatini, Paolo; Casiglia, Edoardo; Gąsowski, Jerzy; Głuszek, Jerzy; Jankowski, Piotr; Narkiewicz, Krzysztof; Saladini, Francesca; Stolarz-Skrzypek, Katarzyna; Tikhonoff, Valérie; Van Bortel, Luc; Wojciechowska, Wiktoria; Kawecka-Jaszcz, Kalina

    2011-01-01

    This review summarizes several scientific contributions at the recent Satellite Symposium of the European Society of Hypertension, held in Milan, Italy. Arterial stiffening and its hemodynamic consequences can be easily and reliably measured using a range of noninvasive techniques. However, like blood pressure (BP) measurements, arterial stiffness should be measured carefully under standardized patient conditions. Carotid-femoral pulse wave velocity has been proposed as the gold standard for arterial stiffness measurement and is a well recognized predictor of adverse cardiovascular outcome. Systolic BP and pulse pressure in the ascending aorta may be lower than pressures measured in the upper limb, especially in young individuals. A number of studies suggest closer correlation of end-organ damage with central BP than with peripheral BP, and central BP may provide additional prognostic information regarding cardiovascular risk. Moreover, BP-lowering drugs can have differential effects on central aortic pressures and hemodynamics compared with brachial BP. This may explain the greater beneficial effect provided by newer antihypertensive drugs beyond peripheral BP reduction. Although many methodological problems still hinder the wide clinical application of parameters of arterial stiffness, these will likely contribute to cardiovascular assessment and management in future clinical practice. Each of the abovementioned parameters reflects a different characteristic of the atherosclerotic process, involving functional and/or morphological changes in the vessel wall. Therefore, acquiring simultaneous measurements of different parameters of vascular function and structure could theoretically enhance the power to improve risk stratification. Continuous technological effort is necessary to refine our methods of investigation in order to detect early arterial abnormalities. Arterial stiffness and its consequences represent the great challenge of the twenty-first century for

  3. 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.

  4. 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.

  5. 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.

  6. Bi-stable optical actuator

    Science.gov (United States)

    Holdener, Fred R.; Boyd, Robert D.

    2000-01-01

    The present invention is a bi-stable optical actuator device that is depowered in both stable positions. A bearing is used to transfer motion and smoothly transition from one state to another. The optical actuator device may be maintained in a stable position either by gravity or a restraining device.

  7. Clinical and Hemodynamic Effects of CPAP-Therapy in Patients with Cardiogenic Pulmonary Edema

    Directory of Open Access Journals (Sweden)

    M. V. Gorbunova

    2007-01-01

    Full Text Available Objective: to evaluate the clinical and hemodynamic effects of CPAP-therapy in the treatment of alveolar cardiogenic pulmonary edema (CPE in patients with acute myocardial infarction (AMI.Subjects and methods. The open-labeled prospective study included 22 patients (19 males; mean age, 59.2±5.8 years with CPE that had complicated the course of AMI. Despite the drug and oxygen therapies of CPE for 30 minutes, progressive respiratory and left ventricular failures were an indication for the initiation of CPAP-therapy (7.3±1.2 cm H2O that was performed, by employing REM-Star apparatuses (Respironics, USA and Ultra Mirage facial masks (ResMed, Australia. Oxygen, 2 l/min (FiO2 = 40%, was delivered through the mask circuit. Central hemodynamic parameters were measured before and 60 and 180 minutes after the initiation of CPAP-therapy, by using a Swan-Ganz thermodilution cathether (HANDS OFF, model AH-05000-H, ARROW, USA. Arterial and mixed venous blood gas composition was rapidly determined on an automatic gas analyzer (Rapidlab 348, Bayer, USA.Results. Cyanosis and acrocyanosis disappeared and the number of congestive moist rales reduced in the lung in 19 (86.4% patients during 30-min CPAP-therapy. The patients’ oxygen status changed: the value of PaO2 significantly increased (82.5±2.5 versus 57.4±4.2 mm Hg at the baseline;p<0.05; SaO2 reached the normal values 60 minutes following CPAP-therapy. There was an increase in the cardiac index (3.1±0.2 versus 2.3±0.1 l/min/m2 at the baseline; p<0.05, a decrease in pulmonary wedge pressure (14.4±21 versus 23.6±2.1 mm Hg at the baseline; p<0.05, and synchronism of right and left cardiac performance.Conclusion. CPAP-therapy optimizes treatment of patients with CPE-complicated AMI, results in the normalization of the arterial blood gas composition, significantly diminishes hydrostatic pulmonary capillary pressure, and promotes the synchronism of the right and left hearts. 

  8. Avaliação hemodinâmica em paciente criticamente enfermo Hemodynamic assessment in the critically ill patient

    Directory of Open Access Journals (Sweden)

    Paulo Novis Rocha

    2010-06-01

    Full Text Available Uma fração crescente das atividades clínicas dos nefrologistas é exercida nas unidades de terapia intensiva (UTIs. Ao avaliar pacientes com insuficiência renal aguda no contexto de choque circulatório, que também apresentam anasarca e/ou trocas gasosas ruins, o nefrologista precisa decidir entre duas condutas antagônicas: 1 remover volume através de diálise ou diureticoterapia para melhorar o quadro edematoso; 2 administrar volume para melhorar a hemodinâmica. Para minimizar a chance de decisões incorretas, é imperativo que o nefrologista conheça as ferramentas disponíveis para avaliação hemodinâmica invasiva e de estimativa de adequação da volemia no paciente com doença crítica. Neste artigo, fazemos uma breve revisão da fisiologia da regulação do volume do líquido extracelular e, em seguida, abordamos o diagnóstico de volemia, com base em critérios clínicos e hemodinâmicos.A growing fraction of the clinical duties of Nephrologists is undertaken inside intensive care units. While assessing patients with acute renal failure in the context of circulatory collapse, which are also edematous and/or with impaired gas exchanges, the Nephrologist must decide between two opposing therapies: 1 remove volume with the aid of dialysis or diuretics to improve the edematous state; 2 volume expand to improve hemodynamics. To minimize the odds of making incorrect choices, the Nephrologist must be familiar with the tools available for determining the adequacy of volume status and for invasive hemodynamic monitoring in the critically ill patient. In this manuscript, we will briefly review the physiology of extra cellular fluid volume regulation and then tackle the issue of volume status assessment, based on clinical and hemodynamic criteria.

  9. Correlation between electrical and hemodynamic responses during visual stimulation with graded contrasts

    Science.gov (United States)

    Si, Juanning; Zhang, Xin; Li, Yuejun; Zhang, Yujin; Zuo, Nianming; Jiang, Tianzi

    2016-09-01

    Brain functional activity involves complex cellular, metabolic, and vascular chain reactions, making it difficult to comprehend. Electroencephalography (EEG) and functional near infrared spectroscopy (fNIRS) have been combined into a multimodal neuroimaging method that captures both electrophysiological and hemodynamic information to explore the spatiotemporal characteristics of brain activity. Because of the significance of visually evoked functional activity in clinical applications, numerous studies have explored the amplitude of the visual evoked potential (VEP) to clarify its relationship with the hemodynamic response. However, relatively few studies have investigated the influence of latency, which has been frequently used to diagnose visual diseases, on the hemodynamic response. Moreover, because the latency and the amplitude of VEPs have different roles in coding visual information, investigating the relationship between latency and the hemodynamic response should be helpful. In this study, checkerboard reversal tasks with graded contrasts were used to evoke visual functional activity. Both EEG and fNIRS were employed to investigate the relationship between neuronal electrophysiological activities and the hemodynamic responses. The VEP amplitudes were linearly correlated with the hemodynamic response, but the VEP latency showed a negative linear correlation with the hemodynamic response.

  10. Stable isotope enrichment: Current and future potential

    International Nuclear Information System (INIS)

    Tracy, J.G.; Aaron, W.S.

    1992-01-01

    Oak Ridge National Laboratory (ORNL) operates the Isotope Enrichment Facility for the purpose of providing enriched stable isotopes, selected radioactive isotopes (including the actinides), and isotope-related materials and services for use in various research applications. ORNL is responsible for isotope enrichment and the distribution of approximately 225 nongaseous stable isotopes from 50 multi-isotopic elements. Many enriched isotope products are of prime importance in the fabrication of nuclear targets and the subsequent production of special radionuclides. State-of-the-art techniques to achieve special isotopic, chemical, and physical requirements are performed at ORNL This report describes the status and capabilities of the Isotope Enrichment Facility and the Isotope Research Materials Laboratory as well as emphasizing potential advancements in enrichment capabilities

  11. Stable isotope enrichment - current and future potential

    International Nuclear Information System (INIS)

    Tracy, J.G.; Aaron, W.S.

    1993-01-01

    Oak Ridge National Laboratory (ORNL) operates the Isotope Enrichment Facility for the purpose of providing enriched stable isotopes, selected radioactive isotopes (including the actinides), and isotope-related materials and services for use in various research applications. ORNL is responsible for isotope enrichment and the distribution of approximately 225 nongaseous stable isotopes from 50 multi-isotopic elements. Many enriched isotope products are of prime importance in the fabrication of nuclear targets and the subsequent production of special radionuclides. State-of-the-art techniques to achieve special isotopic, chemical, and physical requirements are performed at ORNL. This report describes the status and capabilities of the Isotope Enrichment Facility and the Isotope Research Materials Laboratory as well as emphasizing potential advancements in enrichment capabilities. (orig.)

  12. Resting-state hemodynamics are spatiotemporally coupled to synchronized and symmetric neural activity in excitatory neurons

    Science.gov (United States)

    Ma, Ying; Shaik, Mohammed A.; Kozberg, Mariel G.; Portes, Jacob P.; Timerman, Dmitriy

    2016-01-01

    Brain hemodynamics serve as a proxy for neural activity in a range of noninvasive neuroimaging techniques including functional magnetic resonance imaging (fMRI). In resting-state fMRI, hemodynamic fluctuations have been found to exhibit patterns of bilateral synchrony, with correlated regions inferred to have functional connectivity. However, the relationship between resting-state hemodynamics and underlying neural activity has not been well established, making the neural underpinnings of functional connectivity networks unclear. In this study, neural activity and hemodynamics were recorded simultaneously over the bilateral cortex of awake and anesthetized Thy1-GCaMP mice using wide-field optical mapping. Neural activity was visualized via selective expression of the calcium-sensitive fluorophore GCaMP in layer 2/3 and 5 excitatory neurons. Characteristic patterns of resting-state hemodynamics were accompanied by more rapidly changing bilateral patterns of resting-state neural activity. Spatiotemporal hemodynamics could be modeled by convolving this neural activity with hemodynamic response functions derived through both deconvolution and gamma-variate fitting. Simultaneous imaging and electrophysiology confirmed that Thy1-GCaMP signals are well-predicted by multiunit activity. Neurovascular coupling between resting-state neural activity and hemodynamics was robust and fast in awake animals, whereas coupling in urethane-anesthetized animals was slower, and in some cases included lower-frequency (resting-state hemodynamics in the awake and anesthetized brain are coupled to underlying patterns of excitatory neural activity. The patterns of bilaterally-symmetric spontaneous neural activity revealed by wide-field Thy1-GCaMP imaging may depict the neural foundation of functional connectivity networks detected in resting-state fMRI. PMID:27974609

  13. 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

  14. [Indicators of general, cerebral, and regional hemodynamics in myopic schoolchildren aged 13-15 years].

    Science.gov (United States)

    Iastrebtseva, T A; Chuprov, A D; Plotnikova, Iu A

    2002-01-01

    110 schoolchildren aged 13-15 years were examined. 24 of them had pseudomyopia and 6 patients myopia of various forms. A control group consisted of 38 children. Central hemodynamics was estimated by average dynamic pressure, cerebral hemodynamics--by rheoencephalography, regional hemodynamics--by dopplerography of the internal carotid and suprapubic arteries. It was found that with myopia progression, the average dynamic pressure positively comes down with reduction of reographic waves amplitude in rheogram. The blood flow rate in internal carotid and suprapubic arteries has no substantial impact on myopia course. Predisposition to arterial hypotension is a risk factor for myopia development and progression.

  15. 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

    2017-06-01

    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 knowledge concerning physiology were examined with a pre-and posttest. Simply by observation of one's own hemodynamic variables, the understanding of complex physiological concepts was significantly enhanced. Copyright © 2017 the American Physiological Society.

  16. Hemodynamic determinants of dyspnea improvement in acute decompensated heart failure.

    Science.gov (United States)

    Solomonica, Amir; Burger, Andrew J; Aronson, Doron

    2013-01-01

    Dyspnea relief constitutes a major treatment goal and a key measure of treatment efficacy in decompensated heart failure. However, there are no data with regard to the relationship between hemodynamic measurements during treatment and dyspnea improvement. We studied 233 patients assigned to right heart catheterization in the Vasodilation in the Management of Acute Congestive Heart Failure trial. Dyspnea (assessed using a 7-point Likert scale) and hemodynamic parameters were measured simultaneously at 15 and 30 minutes and 1, 2, 3, 6, and 24 hours. Dyspnea relief was defined as moderate or marked improvement. There was a time-dependent association between the reductions in pulmonary capillary wedge pressure (PCWP; 25.4, 24.6, 24.0, 23.5, 23.4, 21.5, and 19.9 mm Hg) and the percentage of patients achieving dyspnea relief (17.7%, 24.6%, 32.2%, 36.2%, 37.8%, 47.4%, and 66.1%, in the respective time points). Multivariable logistic generalized estimating equations modeling demonstrated that reductions of both PCWP and mean pulmonary artery pressure were independently associated with dyspnea relief. Compared with the highest PCWP quartile, the adjusted odds ratios for dyspnea relief were 0.92 (95% confidence interval [CI], 0.67-1.29), 1.07 (95% CI, 0.75-1.55), and 1.80 (95% CI, 1.22-2.65) in the third, second, and first PCWP quartiles, respectively (P(trend)=0.003). Compared with the highest mean pulmonary artery pressure quartile, the adjusted odds ratios for dyspnea relief were 2.0 (95% CI, 1.41-2.82), 2.23 (95% CI, 1.52-3.27), and 2.98 (95% CI, 1.91-4.66) in the third, second, and first mean pulmonary artery pressure quartiles, respectively (P(trend)<0.0001). A clinically significant improvement in dyspnea is associated with a reduction in both PCWP and mean pulmonary artery pressure.

  17. 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....... METHODS: Sixty-two healthy participants, evenly distributed with respect to age (20 to 80 years) and sex (32 women/30 men), were prospectively enrolled in the study. Participants were all deemed healthy by medical history, echocardiography, exercise test, spirometry, blood tests, and electrocardiogram....... Participants had hemodynamic parameters measured using right heart catheterization during rest, passive leg raise, and incremental exercise. RESULTS: During rest, all hemodynamic parameters were similar between age groups, apart from blood pressure. During leg raise and incremental exercise...

  18. 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

  19. Hemodynamic pattern in myocardial infarction patients at the common stages of rehabilitation

    International Nuclear Information System (INIS)

    Perepech, N.B.

    1986-01-01

    Integrated body rheography, radiocardiography and radionuclide ventriculography were used to investigate hemodynamic changes in 101 myocardial infarction patients during the hospital stage of the disease. Changes in major hemodynamic parameters were demonstrated by the end of the 1st week and when walking was resumed. At the resumed-walking stage, the mechanism of declining stroke and cardiac indices was shown to depend on physical activation rates. Hemodynamic response is mostly conditioned by myocardial insufficiency when walking is resumed rapidly during the 2nd week, and by smaller venous return due to hypovolemia where it is resumed slowly during the 4th week. Expanding motion regimens at slow rates results in persistent hemodynamic disturbances in myocardial infarction patients

  20. Hemodynamic comparison of mild and severe preeclampsia: concept of stroke systemic vascular resistance index.

    Science.gov (United States)

    Scardo, J; Kiser, R; Dillon, A; Brost, B; Newman, R

    1996-01-01

    Our purpose was to compare baseline hemodynamic parameters of mild and severe preeclampsia. Patients admitted to the Medical University Labor and Delivery Unit with the diagnosis of preeclampsia who had not received prior antihypertensive or magnesium sulfate therapy were recruited for noninvasive hemodynamic monitoring with thoracic electrical bioimpedance. After stabilization in the lateral recumbent position, hemodynamic monitoring was begun. Baseline hemodynamic parameters, mean arterial pressure (MAP), heart rate (HR), systemic vascular resistance index (SVRI), cardiac index (CI), and stroke index (SI) were recorded. Stroke systemic vascular resistance index (SSVRI), the resistance imposed by vasculature on each beat of the heart, was calculated for each patient by multiplying SVRI by HR. For statistical analysis, unpaired Student's t-tests (two-tailed) were utilized (P preclampsia appears to be a more intensely vasoconstricted state than mild preeclampsia. Although CI is inversely proportional to SVRI, increased HR in severe preeclampsia prevents this expected decrease in cardiac output.

  1. Hemodynamic deterioration precedes onset of ventricular tachyarrhythmia after Heartmate II implantation.

    Science.gov (United States)

    Yaksh, Ameeta; Kik, Charles; Knops, Paul; Zwiers, Korinne; van Ettinger, Maarten J B; Manintveld, Olivier C; de Wijs, Marcel C J; van der Kemp, Peter; Bogers, Ad J J C; de Groot, Natasja M S

    2016-07-08

    Early postoperative ventricular tachyarrhythmia (PoVT) after left ventricular assist device (LVAD) implantation are common and associated with higher mortality-rates. At present, there is no data on initiation of these PoVT and the role of alterations in cardiac hemodynamics. A LVAD was implanted in a patient with end-stage heart failure due to a ischemic cardiomyopathy. Alterations in cardiac rhythm and hemodynamics preceding PoVT-episodes during the first five postoperative days were examined by using continuous recordings of cardiac rhythm and various hemodynamic parameters. All PoVT (N=120) were monomorphic, most often preceded by short-long-short-sequences or regular SR and initiated by ventricular runs. Prior to PoVT, mean arterial pressure decreased; heart rate and ST-segments deviations increased. PoVT are caused by different underlying electrophysiological mechanisms. Yet, they are all monomorphic and preceded by hemodynamic deterioration due to myocardial ischemia.

  2. A review of the hemodynamic effects of external leg and lower body compression.

    Science.gov (United States)

    Helmi, M; Gommers, D; Groeneveld, A B J

    2014-03-01

    External leg and lower body compression (ELC) has been used for decades in the prevention of deep vein thrombosis and the treatment of leg ischemia. Because of systemic effects, the methods have regained interest in anesthesia, surgery and critical care. This review intends to summarize hemodynamic effects and their mechanisms. Compilation of relevant literature published in English as full paper and retrieved from Medline. By compressing veins, venous stasis is diminished and venous return and arterial blood flow are increased. ELC has been suggested to improve systemic hemodynamics, in different clinical settings, such as postural hypotension, anesthesia, surgery, shock, cardiopulmonary resuscitation and mechanical ventilation. However, the hemodynamic alterations depend upon the magnitude, extent, cycle, duration and thus the modality of ELC, when applied in a static or intermittent fashion (by pneumatic inflation), respectively. ELC may help future research and optimizing treatment of hemodynamically unstable, surgical or critically ill patients, independent of plasma volume expansion.

  3. Comparison of the hemodynamic effects of etomidate between hypertensive and normotensive patients

    Directory of Open Access Journals (Sweden)

    Hayrettin Daşkaya

    2014-06-01

    Full Text Available Objective: Comparison of the hemodynamic effect of ethomidate induction in normotensive and hypertensive patients. Methods: Forty ASA 1-2 patients were included. After informed consent were obtained, patients were divided into two group; Group H: Hypertensive patients, Group N: Normotensive patients. Fentanile and midazolam were administrated for premedication. Anesthesia induction was performed by etomidate 0.3 mg/kg and rocuronium 0.6 mg/kg. Arterial pressures and heart rates were measured at certain intervals: control, pre-intubation and 1, 3 and 5 min post-intubation. Myoclonic movements and hemodynamic parameters were noted by an anesthetist who was masked to the groups. Results: Hemodynamic parameters were higher in hypertensive patients but were in clinically tolerable limits. Conclusion: No hemodynamic instability was observed in anesthesia induction with ethomidate in neither hypertensive nor normotensive patients. J Clin Exp Invest 2014; 5 (2: 164-168

  4. 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.

  5. 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

  6. 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...

  7. 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...

  8. One-dimensional stable distributions

    CERN Document Server

    Zolotarev, V M

    1986-01-01

    This is the first book specifically devoted to a systematic exposition of the essential facts known about the properties of stable distributions. In addition to its main focus on the analytic properties of stable laws, the book also includes examples of the occurrence of stable distributions in applied problems and a chapter on the problem of statistical estimation of the parameters determining stable laws. A valuable feature of the book is the author's use of several formally different ways of expressing characteristic functions corresponding to these laws.

  9. 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.

  10. 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.

  11. [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.

  12. Hemodynamic forces regulate developmental patterning of atrial conduction.

    Directory of Open Access Journals (Sweden)

    Michael C Bressan

    Full Text Available Anomalous action potential conduction through the atrial chambers of the heart can lead to severe cardiac arrhythmia. To date, however, little is known regarding the mechanisms that pattern proper atrial conduction during development. Here we demonstrate that atrial muscle functionally diversifies into at least two heterogeneous subtypes, thin-walled myocardium and rapidly conducting muscle bundles, during a developmental window just following cardiac looping. During this process, atrial muscle bundles become enriched for the fast conduction markers Cx40 and Nav1.5, similar to the precursors of the fast conduction Purkinje fiber network located within the trabeculae of the ventricles. In contrast to the ventricular trabeculae, however, atrial muscle bundles display an increased proliferation rate when compared to the surrounding myocardium. Interestingly, mechanical loading of the embryonic atrial muscle resulted in an induction of Cx40, Nav1.5 and the cell cycle marker Cyclin D1, while decreasing atrial pressure via in vivo ligation of the vitelline blood vessels results in decreased atrial conduction velocity. Taken together, these data establish a novel model for atrial conduction patterning, whereby hemodynamic stretch coordinately induces proliferation and fast conduction marker expression, which in turn promotes the formation of large diameter muscle bundles to serve as preferential routes of conduction.

  13. Effect of Aspirin Supplementation on Hemodynamics in Older Firefighters.

    Science.gov (United States)

    Lane-Cordova, Abbi D; Ranadive, Sushant M; Yan, Huimin; Kappus, Rebecca M; Sun, Peng; Bunsawat, Kanokwan; Smith, Denise L; Horn, Gavin P; Ploutz-Snyder, Robert; Fernhall, B O

    2015-12-01

    Cardiovascular events are the leading cause of line-of-duty fatality for firefighters. Aspirin reduces the risk of cardiovascular events in men and may reduce fatalities in older (>40 yr) firefighters. We hypothesized that both chronic and acute aspirin supplementation would improve vascular function after live firefighting but that chronic supplementation would also improve resting hemodynamics. Twenty-four firefighters (40-60 yr) were randomly assigned to acute or chronic aspirin supplementation or placebo in a balanced, crossover design. Arterial stiffness, brachial and central blood pressures, as well as forearm vasodilatory capacity and blood flow were measured at rest and immediately after live firefighting. Total hyperemic blood flow (area under the curve (AUC)) was increased (P 0.05 for interaction). Arterial stiffness/central blood pressure increased (P < 0.04) with no effect of aspirin (from 0.0811 ± 0.001 to 0.0844 ± 0.003 m·s·mm⁻¹ Hg⁻¹ in aspirin condition versus 0.0802 ± 0.002 to 0.0858 ± 0.002 m·s⁻¹·mm Hg⁻¹ in placebo condition), whereas peripheral and central systolic and pulse pressures decreased after firefighting across conditions (P < 0.05). Live firefighting resulted in increased AUC and pressure-controlled arterial stiffness and decreased blood pressure in older firefighters, but aspirin supplementation did not affect macro- or microvascular responsiveness at rest or after firefighting.

  14. Remote Left Ventricular Hemodynamic Monitoring Using a Novel Intracardiac Sensor.

    Science.gov (United States)

    Mondritzki, Thomas; Boehme, Philip; White, Jason; Park, Jin Woo; Hoffmann, Jessica; Vogel, Julia; Kolkhof, Peter; Walsh, Stuart; Sandner, Peter; Bischoff, Erwin; Dinh, Wilfried; Hüser, Jörg; Truebel, Hubert

    2018-05-01

    Heart failure (HF) remains the most common reason for hospital admission in patients aged >65 years. Despite modern drug therapy, mortality and readmission rates for patients hospitalized with HF remain high. This necessitates further research to identify early patients at risk for readmission to limit hospitalization by timely adjustment of medical therapy. Implantable devices can monitor left ventricular (LV) hemodynamics and remotely and continuously detect the early signs of decompensation to trigger interventions and reduce the risk of hospitalization for HF. Here, we report the first preclinical study validating a new batteryless and easy to implant LV-microelectromechanical system to assess LV performance. A miniaturized implantable wireless pressure sensor was adapted for implantation in the LV apex. The LV-microelectromechanical system sensor was tested in a canine model of HF. The wireless pressure sensor measurements were compared with invasive left heart catheter-derived measurements at several time points. During different pharmacological challenge studies with dobutamine or vasopressin, the device was equally sensitive compared with invasive standard procedures. No adverse events or any observable reaction related to the implantation and application of the device for a period of 35 days was observed. Our miniaturized wireless pressure sensor placed in the LV (LV-microelectromechanical system) has the potential to become a new telemetric tool to earlier identify patients at risk for HF decompensation and to guide the treatment of patients with HF. © 2018 American Heart Association, Inc.

  15. 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

  16. 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.

  17. 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.

  18. 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.

  19. 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.

  20. 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.

  1. Occupational doses in medical staff during hemodynamic procedures

    International Nuclear Information System (INIS)

    Alonso, Thessa C.; Silva, Teogenes A. da

    2008-01-01

    The main objective of an occupational radiation program for workers is to keep radiation exposures under control and to assure that radiation protection principles are followed. Due to different types of interventionist medical exams, usually the medical staffs are highly exposed to radiation, which it emphasizes that it is required safety procedures for dose reduction. In this work, studies were concerned with individual doses of medical staff that are directly engaged to interventionist procedures at hemodynamic services. Dose values from a data bank of the CDTN Individual Monitoring Service (IMS) were analyzed and measurements with film type and thermoluminescent (TL) dosimeters were performed for comparison purposes. Additionally, the influence of the use of a lead apron on the individual dose was investigated. Results suggested that the medical staff does not care about wearing the routine personal dosimeter and that the registered doses may not be representative to the actual annual effective doses. They also showed that effective doses are highly dependent on the characteristics and conditions of the lead apron that is worn by the medical staff. It is concluded that it is important to have personal dosimetric system up-graded for reliable measurements, to define an adequate algorithm for determining the effective dose and to train the medical staff to follow the basic radiation protection principle of optimization. (author)

  2. Prevalence and hemodynamic effects of leaning during CPR

    Science.gov (United States)

    Niles, Dana E.; Sutton, Robert M.; Nadkarni, Vinay M.; Glatz, Andrew; Zuercher, Mathias; Maltese, Matthew R.; Eilevstjønn, Joar; Abella, Benjamin S.; Becker, Lance B.; Berg, Robert A.

    2013-01-01

    Background Cardiopulmonary resuscitation (CPR) guidelines recommend complete release between chest compressions (CC). Objective Evaluate the hemodynamic effects of leaning (incomplete chest wall release) during CPR and the prevalence of leaning during CPR. Results In piglet ventricular fibrillation cardiac arrests, 10% and 20% (1.8 kg and 3.6 kg, respectively), leaning during CPR increased right atrial pressures, decreased coronary perfusion pressures, and decreased cardiac index and left ventricular myocardial blood flow by nearly 50%. In contrast, residual leaning of a 260 g accelerometer/ force feedback device did not adversely affect cardiac index or myocardial blood flow. Among 108 adult in-hospital CPR events, leaning ≥2.5 kg was demonstrable in 91% of the events and 12% of the evaluated CC. For 12 children with in-hospital CPR, 28% of CC had residual leaning ≥2.5 kg and 89% had residual leaning ≥0.5 kg. Conclusions Leaning during CPR increases intrathoracic pressure, decreases coronary perfusion pressure, and decreases cardiac output and myocardial blood flow. Leaning is common during CPR. PMID:22208173

  3. 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.

  4. 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.

  5. 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

  6. 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.

  7. Evaluation of the occupational dose in hemodynamic procedures

    International Nuclear Information System (INIS)

    Silva, Amanda J. da; Fernandes, Ivani M.; Sordi, Gian Maria A.A.; Carneiro, Janete C. Gaburo

    2010-01-01

    The purpose of this study was to evaluate the dose received by health professionals in a hemodynamic service. It was necessary to know the profile of these professional, to carry out a survey the occupational external doses during the years 2000 to 2009 and to evaluate the distribution of the effective dose from the special procedures guided by fluoroscopy. A self-applied questionnaire was used to delineate the profile of health professionals, taking into account variables such as gender, age, individual monitoring time, number of jobs and tasks performed in the sector. In addition, it was performed an examination of the external individual monitoring doses from the records of the institution. The sample was composed of 35 professionals, 11 males and 24 females, with mean age of (43.0 +- 10.4) years. The average monitoring time of individuals analyzed within the institution was (11.3 +- 9.1) years, considering the period before the study. The minimum record dose level was 0.2 mSv and the maximum dose was 22.7 mSv. Doctors and nursing assistants were the professionals more exposed to radiation, due probably remaining closer to the examination table and X-ray tube during the interventional procedure. (author)

  8. 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

  9. The effect of verapamil as an adjuvant agent with local anesthetic on sensory block level, hemodynamic and postoperative pain

    International Nuclear Information System (INIS)

    Tabaeizavareh, M.H.; Omranifard, M.

    2012-01-01

    Objective: Coadministration of verapamil with local anesthetics could potentiate the sensory block of peripheral nerve, increase the duration of sensory nerve block and reduce postoperative pain and analgesic consumption. The aim of this study was to investigate the effect of verapamil as an adjuvant with bupivacaine on level of sensory block, post-operative pain and analgesic consumption among patients undergone elective surgery in Isfahan. Methodology: In this prospective randomized interventional clinical double-blind study ASA physical status I or II male patients referred for elective lower abdominal surgery were enrolled. They randomized in group A (20 cc of 0.5% bupivacaine plus 5 mg verapamil) and B(20 cc of 0.5% bupivacaine plus 2 cc normal saline). The sensory level block, postoperative pain, opioid consumption and vomiting and nausa and hemodynamic state was recorded and compared in two groups. Results: Sixty two patients were studied. Mean of the sensory level block 20 minutes after stating epidural anesthesia and immediately after surgery, postoperative pain score, opioid consumption and nausea and vomiting and fluid intake was not significantly different in two groups (P>0.05). Mean of systolic and diastolic blood pressure and pulse rate changes was not significantly different in two groups (P>0.05). Conclusion: Verapamil as an adjuvant with bupivacaine could not significantly increase the level of sensory block and attenuate post-operative pain and analgesic consumption and hemodynamic condition of the patients. For more accurate results it is recommended to determine the effect of different dose of verapamil in larger sample size of the patients. Studying the effect of other Ca channel blockers would be favorable in this regard. (author)

  10. Stable isotope research pool inventory

    International Nuclear Information System (INIS)

    1980-12-01

    This report contains a listing of electromagnetically separated stable isotopes which are available for distribution within the United States for non-destructive research use from the Oak Ridge National Laboratory on a loan basis. This inventory includes all samples of stable isotopes in the Materials Research Collection and does not designate whether a sample is out on loan or in reprocessing

  11. Regional variation in interhemispheric coordination of intrinsic hemodynamic fluctuations.

    Science.gov (United States)

    Stark, David E; Margulies, Daniel S; Shehzad, Zarrar E; Reiss, Philip; Kelly, A M Clare; Uddin, Lucina Q; Gee, Dylan G; Roy, Amy K; Banich, Marie T; Castellanos, F Xavier; Milham, Michael P

    2008-12-17

    Electrophysiological studies have long demonstrated a high degree of correlated activity between the left and right hemispheres, however little is known about regional variation in this interhemispheric coordination. Whereas cognitive models and neuroanatomical evidence suggest differences in coordination across primary sensory-motor cortices versus higher-order association areas, these have not been characterized. Here, we used resting-state functional magnetic resonance imaging data acquired from 62 healthy volunteers to examine interregional correlation in spontaneous low-frequency hemodynamic fluctuations. Using a probabilistic atlas, we correlated probability-weighted time series from 112 regions comprising the entire cerebrum. We then examined regional variation in correlated activity between homotopic regions, contrasting primary sensory-motor cortices, unimodal association areas, and heteromodal association areas. Consistent with previous studies, robustly correlated spontaneous activity was noted between all homotopic regions, which was significantly higher than that between nonhomotopic (heterotopic and intrahemispheric) regions. We further demonstrated substantial regional variation in homotopic interhemispheric correlations that was highly consistent across subjects. Specifically, there was a gradient of interhemispheric correlation, with highest correlations across primary sensory-motor cortices (0.758, SD=0.152), significantly lower correlations across unimodal association areas (0.597, SD=0.230) and still lower correlations across heteromodal association areas (0.517, SD=0.226). These results demonstrate functional differences in interhemispheric coordination related to the brain's hierarchical subdivisions. Synchrony across primary cortices may reflect networks engaged in bilateral sensory integration and motor coordination, whereas lower coordination across heteromodal association areas is consistent with functional lateralization of these regions

  12. 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.)

  13. Hemodynamic and permeability characteristics of acute experimental necrotizing enterocolitis

    International Nuclear Information System (INIS)

    Miller, M.J.; Adams, J.; Gu, X.A.; Zhang, X.J.; Clark, D.A.

    1990-01-01

    We examined the local hemodynamic response of intestinal loops during acute necrotizing enterocolitis (NEC) in anesthetized rabbits. NEC was induced in ileal loops by transmural injection of a solution containing casein (10 mg/ml) and calcium gluconate (50 mg/ml) acidified to pH 4.0 with propionic or acetic acid. Control loops received casein only (pH 5.0). Mucosal damage was quantified by the blood-to-lumen movement of [51Cr]EDTA, fluid shifts into the lumen, and histology. Mean arterial pressure and loop blood flow were steady over the 3-hr period, loop fluid volume decreased, and there was no evidence of necrosis or epithelial damage. In loops receiving acidified casein and calcium gluconate, there was an immediate dramatic increase in loop blood flow that returned to baseline by 50 min. In addition, loop fluid volume was dramatically increased, necrosis was noted in the form of blunting and loss of villi, and sevenfold increase in [51Cr]EDTA permeability was evident. Administration of CV 1808 (30 mg/kg/hr), a selective adenosine2 agonist, which maintained and elevated loop blood flow throughout the 3 hr protocol, failed to alter the changes in loop fluid volume or prevent necrosis. Histamine levels in loop fluid levels were significantly elevated 20-30 min after NEC induction when compared to saline controls, indicating an early activation of mucosal defenses with this luminal insult. Thus, this model of NEC is characterized by a transient, acute hyperemia, increased intestinal permeability, and histamine release. As mucosal damage was independent of ischemia and could not be prevented by vasodilatory therapy, this model supports the clinical findings that NEC is correlated with luminal factors related to feeding and independent of cardiovascular stress

  14. Ambient Temperature and Cerebrovascular Hemodynamics in the Elderly.

    Science.gov (United States)

    Pan, Wen-Chi; Eliot, Melissa N; Koutrakis, Petros; Coull, Brent A; Sorond, Farzaneh A; Wellenius, Gregory A

    2015-01-01

    Some prior studies have linked ambient temperature with risk of cerebrovascular events. If causal, the pathophysiologic mechanisms underlying this putative association remain unknown. Temperature-related changes in cerebral vascular function may play a role, but this hypothesis has not been previously evaluated. We evaluated the association between ambient temperature and cerebral vascular function among 432 participants ≥65 years old from the MOBILIZE Boston Study with data on cerebrovascular blood flow, cerebrovascular resistance, and cerebrovascular reactivity in the middle cerebral artery. We used linear regression models to assess the association of mean ambient temperature in the previous 1 to 28 days with cerebrovascular hemodynamics adjusting for potential confounding factors. A 10°C increase in the 21-day moving average of ambient temperature was associated with a 10.1% (95% confidence interval [CI], 2.2%, 17.3%) lower blood flow velocity, a 9.0% (95% CI, 0.7%, 18.0%) higher cerebrovascular resistance, and a 15.3% (95%CI, 2.7%, 26.4%) lower cerebral vasoreactivity. Further adjustment for ozone and fine particulate matter (PM2.5) did not materially alter the results. However, we found statistically significant interactions between ambient temperature and PM2.5 such that the association between temperature and blood flow velocity was attenuated at higher levels of PM2.5. In this elderly population, we found that ambient temperature was negatively associated with cerebral blood flow velocity and cerebrovascular vasoreactivity and positively associated with cerebrovascular resistance. Changes in vascular function may partly underlie the observed associations between ambient temperature and risk of cerebrovascular events.

  15. Central Hemodynamics and Arterial Stiffness in Systemic Sclerosis.

    Science.gov (United States)

    Bartoloni, Elena; Pucci, Giacomo; Cannarile, Francesca; Battista, Francesca; Alunno, Alessia; Giuliani, Marco; Cafaro, Giacomo; Gerli, Roberto; Schillaci, Giuseppe

    2016-12-01

    Although microvascular disease is a hallmark of systemic sclerosis (SSc), a higher prevalence of macrovascular disease and a poorer related prognosis have been reported in SSc than in the general population. The simultaneous assessment of prognostically relevant functional properties of larger and smaller arteries, and their effects on central hemodynamics, has never been performed in SSc using the state-of-the-art techniques. Thirty-four women with SSc (aged 61±15 years, disease duration 17±12 years, and blood pressure 123/70±18/11 mm Hg) and 34 healthy women individually matched by age and mean arterial pressure underwent the determination of carotid-femoral (aortic) and carotid-radial (upper limb) pulse wave velocity (a direct measure of arterial stiffness), aortic augmentation (a measure of the contribution of reflected wave to central pulse pressure), and aortobrachial pulse pressure amplification (brachial/aortic pulse pressure) through applanation tonometry (SphygmoCor). Patients and controls did not differ by carotid-femoral or carotid-radial pulse wave velocity. Aortic augmentation index corrected for a heart rate of 75 bpm (AIx@75) was higher in women with SSc (30.9±16% versus 22.2±12%; P=0.012). Patients also had a lower aortobrachial amplification of pulse pressure (1.22±0.18 versus 1.33±0.25; P=0.041). SSc was an independent predictor of AIx@75 (direct) and pulse pressure amplification (inverse). Among patients, age, mean arterial pressure, and C-reactive protein independently predicted carotid-femoral pulse wave velocity. Age and mean arterial pressure were the only predictors of AIx@75. Women with SSc have increased aortic augmentation and decreased pulse pressure amplification (both measures of the contribution of reflected wave to central waveform) but no changes in aortic or upper limb arterial stiffness. Microvascular involvement occurs earlier than large artery stiffening in SSc. © 2016 American Heart Association, Inc.

  16. Hemodynamic Characteristics Including Pulmonary Hypertension at Rest and During Exercise Before and After Heart Transplantation

    Science.gov (United States)

    Lundgren, Jakob; Rådegran, Göran

    2015-01-01

    Background Little is known about the hemodynamic response to exercise in heart failure patients at various ages before and after heart transplantation (HT). This information is important because postoperative hemodynamics may be a predictor of survival. To investigate the hemodynamic response to HT and exercise, we grouped our patients based on preoperative age and examined their hemodynamics at rest and during exercise before and after HT. Methods and Results Ninety-four patients were evaluated at rest prior to HT with right heart catheterization at our laboratory. Of these patients, 32 were evaluated during slight supine exercise before and 1 year after HT. Postoperative evaluations were performed at rest 1 week after HT and at rest and during exercise at 4 weeks, 3 months, 6 months, and 1 year after HT. The exercise patients were divided into 2 groups based on preoperative age of ≤50 or >50 years. There were no age-dependent differences in the preoperative hemodynamic exercise responses. Hemodynamics markedly improved at rest and during exercise at 1 and 4 weeks, respectively, after HT; however, pulmonary and, in particular, ventricular filling pressures remained high during exercise at 1 year after HT, resulting in normalized pulmonary vascular resistance response but deranged total pulmonary vascular resistance response. Conclusions Our findings suggest that, (1) in patients with heart failure age ≤50 or >50 years may not affect the hemodynamic response to exercise to the same extent as in healthy persons, and (2) total pulmonary vascular resistance may be more adequate than pulmonary vascular resistance for evaluating the exercise response after HT. PMID:26199230

  17. Stable configurations in social networks

    Science.gov (United States)

    Bronski, Jared C.; DeVille, Lee; Ferguson, Timothy; Livesay, Michael

    2018-06-01

    We present and analyze a model of opinion formation on an arbitrary network whose dynamics comes from a global energy function. We study the global and local minimizers of this energy, which we call stable opinion configurations, and describe the global minimizers under certain assumptions on the friendship graph. We show a surprising result that the number of stable configurations is not necessarily monotone in the strength of connection in the social network, i.e. the model sometimes supports more stable configurations when the interpersonal connections are made stronger.

  18. Development of Stable Isotope Technology

    International Nuclear Information System (INIS)

    Jeong, Do Young; Kim, Cheol Jung; Han, Jae Min

    2009-03-01

    KAERI has obtained an advanced technology with singular originality for laser stable isotope separation. Objectives for this project are to get production technology of Tl-203 stable isotope used for medical application and are to establish the foundation of the pilot system, while we are taking aim at 'Laser Isotope Separation Technology to make resistance to the nuclear proliferation'. And we will contribute to ensuring a nuclear transparency in the world society by taking part in a practical group of NSG and being collaboration with various international groups related to stable isotope separation technology

  19. Cognitive function in patients with stable coronary heart disease: Related cerebrovascular and cardiovascular responses.

    Science.gov (United States)

    Gayda, Mathieu; Gremeaux, Vincent; Bherer, Louis; Juneau, Martin; Drigny, Joffrey; Dupuy, Olivier; Lapierre, Gabriel; Labelle, Véronique; Fortier, Annik; Nigam, Anil

    2017-01-01

    Chronic exercise has been shown to prevent or slow age-related decline in cognitive functions in otherwise healthy, asymptomatic individuals. We sought to assess cognitive function in a stable coronary heart disease (CHD) sample and its relationship to cerebral oxygenation-perfusion, cardiac hemodynamic responses, and [Formula: see text] peak compared to age-matched and young healthy control subjects. Twenty-two young healthy controls (YHC), 20 age-matched old healthy controls (OHC) and 25 patients with stable CHD were recruited. Cognitive function assessment included short term-working memory, perceptual abilities, processing speed, cognitive inhibition and flexibility and long-term verbal memory. Maximal cardiopulmonary function (gas exchange analysis), cardiac hemodynamic (impedance cardiography) and left frontal cerebral oxygenation-perfusion (near-infra red spectroscopy) were measured during and after a maximal incremental ergocycle test. Compared to OHC and CHD, YHC had higher [Formula: see text] peak, maximal cardiac index (CI max), cerebral oxygenation-perfusion (ΔO2 Hb, ΔtHb: exercise and recovery) and cognitive function (for all items) (Pcognitive inhibition and flexibility and long-term verbal memory (Pcognitive function (Pcognitive function (Pcognitive function, a similar cerebral oxygenation/perfusion during exercise but reduced one during recovery vs. their aged-matched healthy counterparts. In the all sample, cognitive functions correlated with [Formula: see text] peak, CI max and cerebral oxygenation-perfusion.

  20. Stable isotope research pool inventory

    International Nuclear Information System (INIS)

    1984-03-01

    This report contains a listing of electromagnetically separated stable isotopes which are available at the Oak Ridge National Laboratory for distribution for nondestructive research use on a loan basis. This inventory includes all samples of stable isotopes in the Research Materials Collection and does not designate whether a sample is out on loan or is in reprocessing. For some of the high abundance naturally occurring isotopes, larger amounts can be made available; for example, Ca-40 and Fe-56

  1. French days on stable isotopes

    International Nuclear Information System (INIS)

    2000-01-01

    These first French days on stable isotopes took place in parallel with the 1. French days of environmental chemistry. Both conferences had common plenary sessions. The conference covers all aspects of the use of stable isotopes in the following domains: medicine, biology, environment, tracer techniques, agronomy, food industry, geology, petroleum geochemistry, cosmo-geochemistry, archaeology, bio-geochemistry, hydrology, climatology, nuclear and particle physics, astrophysics, isotope separations etc.. Abstracts available on CD-Rom only. (J.S.)

  2. Stable isotope research pool inventory

    International Nuclear Information System (INIS)

    1982-01-01

    This report contains a listing of electromagnetically separated stable isotopes which are available for distribution within the United States for nondestructive research use from the Oak Ridge National Laboratory on a loan basis. This inventory includes all samples of stable isotopes in the Material Research Collection and does not designate whether a sample is out on loan or in reprocessing. For some of the high abundance naturally occurring isotopes, larger amounts can be made available; for example, Ca-40 and Fe-56

  3. Pharmaceuticals labelled with stable isotopes

    International Nuclear Information System (INIS)

    Krumbiegel, P.

    1986-11-01

    The relatively new field of pharmaceuticals labelled with stable isotopes is reviewed. Scientific, juridical, and ethical questions are discussed concerning the application of these pharmaceuticals in human medicine. 13 C, 15 N, and 2 H are the stable isotopes mainly utilized in metabolic function tests. Methodical contributions are given to the application of 2 H, 13 C, and 15 N pharmaceuticals showing new aspects and different states of development in the field under discussion. (author)

  4. Intraoperative brain hemodynamic response assessment with real-time hyperspectral optical imaging (Conference Presentation)

    Science.gov (United States)

    Laurence, Audrey; Pichette, Julien; Angulo-Rodríguez, Leticia M.; Saint Pierre, Catherine; Lesage, Frédéric; Bouthillier, Alain; Nguyen, Dang Khoa; Leblond, Frédéric

    2016-03-01

    Following normal neuronal activity, there is an increase in cerebral blood flow and cerebral blood volume to provide oxygenated hemoglobin to active neurons. For abnormal activity such as epileptiform discharges, this hemodynamic response may be inadequate to meet the high metabolic demands. To verify this hypothesis, we developed a novel hyperspectral imaging system able to monitor real-time cortical hemodynamic changes during brain surgery. The imaging system is directly integrated into a surgical microscope, using the white-light source for illumination. A snapshot hyperspectral camera is used for detection (4x4 mosaic filter array detecting 16 wavelengths simultaneously). We present calibration experiments where phantoms made of intralipid and food dyes were imaged. Relative concentrations of three dyes were recovered at a video rate of 30 frames per second. We also present hyperspectral recordings during brain surgery of epileptic patients with concurrent electrocorticography recordings. Relative concentration maps of oxygenated and deoxygenated hemoglobin were extracted from the data, allowing real-time studies of hemodynamic changes with a good spatial resolution. Finally, we present preliminary results on phantoms obtained with an integrated spatial frequency domain imaging system to recover tissue optical properties. This additional module, used together with the hyperspectral imaging system, will allow quantification of hemoglobin concentrations maps. Our hyperspectral imaging system offers a new tool to analyze hemodynamic changes, especially in the case of epileptiform discharges. It also offers an opportunity to study brain connectivity by analyzing correlations between hemodynamic responses of different tissue regions.

  5. 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 procedure of vertebral artery ostial stenosis (VAOS). The purpose of the present study is to investigate the influence of stent protrusion length in implantation strategy on the local hemodynamics of the VAOS. CTA images of a 58-year-old female patient with posterior circulation transient ischemic attack were used to perform a 3D reconstruction of the vertebral artery. Five models of the vertebral artery before and after the stent implantation were established. Model 1 was without stent implantation, Model 2-5 was with stent protruding into the subclavian artery for 0, 1, 2, 3 mm, respectively. Computational fluid dynamics simulations based on finite element analysis were employed to mimic the blood flow in arteries and to assess hemodynamic conditions, particularly the blood flow velocity and wall shear stress (WSS). The WSS and the blood flow velocity at the vertebral artery ostium were reduced by 85.33 and 35.36% respectively after stents implantation. The phenomenon of helical flow disappeared. Hemodynamics comparison showed that stent struts that protruded 1 mm into the subclavian artery induced the least decrease in blood speed and WSS. The results suggest that stent implantation can improve the hemodynamics of VAOS, while stent struts that had protruded 1 mm into the subclavian artery would result in less thrombogenesis and neointimal hyperplasia and most likely decrease the risk of ISR.

  6. Quantitative perfusion computed tomography measurements of cerebral hemodynamics: Correlation with digital subtraction angiography identified primary and secondary cerebral collaterals in internal carotid artery occlusive disease

    International Nuclear Information System (INIS)

    Cheng Xiaoqing; Tian Jianming; Zuo Changjing; Liu Jia; Zhang Qi; Lu Guangming

    2012-01-01

    Background: The aim of the present study was to assess hemodynamic variations in symptomatic unilateral internal carotid artery occlusion (ICAO) patients with primary collateral flow via circle of Willis or secondary collateral flow via ophthalmic artery and/or leptomeningeal collaterals. Methods: Thirty-eight patients with a symptomatic unilateral ICAO were enrolled in the study. Based on digital subtraction angiography (DSA) findings, patients were classified into 2 groups: primary collateral (n = 14) and secondary collateral (n = 24) groups. Collateral flow hemodynamics were investigated with perfusion computed tomography (PCT) by measuring the cerebral blood flow (CBF), cerebral blood volume (CBV) and time to peak (TTP) in the hemispheres ipsilateral and contralateral to ICAO. Based on the measurements, the ipsilateral to contralateral ratio for each parameter was calculated and compared. Results: Irrespective of the collateral patterns, ipsilateral CBF was not significantly different from that of the contralateral hemisphere (P = 0.285); ipsilateral CBV and TTP was significantly increased compared with those of the contralateral hemisphere (P = 0.000 and P = 0.000 for CBV and TTP, respectively). Furthermore, patients with secondary collaterals had significantly larger ipsilateral-to-contralateral ratios for both CBV (rCBV, P = 0.0197) and TTP (rTTP, P = 0.000) than those of patients with only primary collaterals. These two groups showed no difference in ipsilateral-to-contralateral ratio for CBF (rCBF, P = 0.312). Conclusion: Patients with symptomatic unilateral ICAO in our study were in an autoregulatory vasodilatation status. Moreover, secondary collaterals in ICAO patients were correlated with ipsilateral CBV and delayed TTP that suggested severe hemodynamic impairment, presumably increasing the risk of ischemic events.

  7. Effects of Lignocaine Administered Intravenously or Intratracheally on Airway and Hemodynamic Responses during Emergence and Extubation in Patients Undergoing Elective Craniotomies in Supine Position.

    Science.gov (United States)

    Shabnum, Tabasum; Ali, Zulfiqar; Naqash, Imtiaz Ahmad; Mir, Aabid Hussain; Azhar, Khan; Zahoor, Syed Amer; Mir, Abdul Waheed

    2017-01-01

    Sympathoadrenergic responses during emergence and extubation can lead to an increase in heart rate (HR) and blood pressure whereas increased airway responses may lead to coughing and laryngospasm. The aim of our study was to compare the effects of lignocaine administered intravenously (IV) or intratracheally on airway and hemodynamic responses during emergence and extubation in patients undergoing elective craniotomies. Sixty patients with physical status American Society of Anaesthesiologists Classes I and II aged 18-70 years, scheduled to undergo elective craniotomies were included. The patients were randomly divided into three groups of twenty patients; Group 1 receiving IV lignocaine and intratracheal placebo (IV group), Group 2 receiving intratracheal lignocaine and IV placebo (I/T group), and Group 3 receiving IV and intratracheal placebo (placebo group). The tolerance to the endotracheal tube was monitored, and number of episodes of cough was recorded during emergence and at the time of extubation. Hemodynamic parameters such as HR and blood pressure (systolic, diastolic, mean arterial pressure) were also recorded. There was a decrease of HR in both IV and intratracheal groups in comparison with placebo group ( P < 0.005). Rise in blood pressure (systolic blood pressure, diastolic blood pressure and mean arterial pressure) was comparable in both Groups 1 and 2 but was lower in comparison with placebo group ( P < 0.005). Cough suppression was comparable in all the three groups. Grade III cough (15%) was documented only in placebo group. Both IV and intratracheal lignocaine are effective in attenuation of hemodynamic response if given within 20 min from skull pin removal to extubation. There was comparable cough suppression through intratracheal route and IV routes than the placebo group.

  8. Renal functional reserve and renal hemodynamics in hypertensive patients.

    Science.gov (United States)

    Gaipov, Abduzhappar; Solak, Yalcin; Zhampeissov, Nurlan; Dzholdasbekova, Aliya; Popova, Nadezhda; Molnar, Miklos Z; Tuganbekova, Saltanat; Iskandirova, Elmira

    2016-10-01

    The renal functional reserve (RFR) is the ability of the kidneys to increase renal plasma flow and glomerular filtration rate (GFR) in response to protein intake. It is a measure of functional and anatomic integrity of nephrons. It is not known what relation between RFR and kidney Doppler parameters. We aimed to study the relation between the RFR and renal hemodynamic parameters in hypertensive patients with and without nephropathy who had normal kidney function. Twenty-four hypertensive subjects with nephropathy (HTN-n, n = 10) and hypertension without nephropathy (HTN, n = 14) were included in the study. Control group included 11 healthy subjects. Baseline GFR (GFR1) and GFR after intake of egg protein 1 mg/kg of body weight were determined (GFR2). RFR was calculated by the following formula: (GFR2-GFR1)/GFR1 × 100%. Doppler ultrasonography was performed. Arterial blood pressure (BP), body mass index (BMI), and estimated GFR were also recorded. HTN and HTN-n groups had impaired levels of RFR compared with controls (p < 0.05), significantly decreased value of flow velocity parameters (Vmax, Vmin), and increased RRI compared with controls. There was significant negative correlation of RFR with blood pressure levels (sBP, r = -0.435, p = 0.009; dBP, r = -0.504, p = 0.002), RRI (r = -0.456, p = 0.008), micro albuminuria (MAU, r = -0.366, p = 0.031) and positive correlation with Vmax and Vmin (r = 0.556, p = 0.001 and r = 0.643, respectively, p < 0.001). Linear regression showed that RRI and MAU were independent predictors of decreased RFR. RFR is lower in hypertensive patients despite near-normal level of kidney function and is related to particular level of BP. RRI and MAU were independent predictors of decreased RFR.

  9. Utility of Angle Correction for Hemodynamic Measurements with Doppler Echocardiography.

    Science.gov (United States)

    Sigurdsson, Martin I; Eoh, Eun J; Chow, Vinca W; Waldron, Nathan H; Cleve, Jayne; Nicoara, Alina; Swaminathan, Madhav

    2018-04-06

    The routine application angle correction (AnC) in hemodynamic measurements with transesophageal echocardiography currently is not recommended but potentially could be beneficial. The authors hypothesized that AnC can be applied reliably and may change grading of aortic stenosis (AS). Retrospective analysis. Single institution, university hospital. During phase I, use of AnC was assessed in 60 consecutive patients with intraoperative transesophageal echocardiography. During phase II, 129 images from a retrospective cohort of 117 cases were used to quantify AS by mean pressure gradient. A panel of observers used custom-written software in Java to measure intra-individual and inter-individual correlation in AnC application, correlation with preoperative transthoracic echocardiography gradients, and regrading of AS after AnC. For phase I, the median AnC was 21 (16-35) degrees, and 17% of patients required no AnC. For phase II, the median AnC was 7 (0-15) degrees, and 37% of assessed images required no AnC. The mean inter-individual and intra-individual correlation for AnC was 0.50 (95% confidence interval [CI] 0.49-0.52) and 0.87 (95% CI 0.82-0.92), respectively. AnC did not improve agreement with the transthoracic echocardiography mean pressure gradient. The mean inter-rater and intra-rater agreement for grading AS severity was 0.82 (95% CI 0.81-0.83) and 0.95 (95% CI 0.91-0.95), respectively. A total of 241 (7%) AS gradings were reclassified after AnC was applied, mostly when the uncorrected mean gradient was within 5 mmHg of the severity classification cutoff. AnC can be performed with a modest inter-rater and intra-rater correlation and high degree of inter-rater and intra-rater agreement for AS severity grading. Copyright © 2018 Elsevier Inc. All rights reserved.

  10. Hemodynamic modelling of BOLD fMRI - A machine learning approach

    DEFF Research Database (Denmark)

    Jacobsen, Danjal Jakup

    2007-01-01

    This Ph.D. thesis concerns the application of machine learning methods to hemodynamic models for BOLD fMRI data. Several such models have been proposed by different researchers, and they have in common a basis in physiological knowledge of the hemodynamic processes involved in the generation...... of the BOLD signal. The BOLD signal is modelled as a non-linear function of underlying, hidden (non-measurable) hemodynamic state variables. The focus of this thesis work has been to develop methods for learning the parameters of such models, both in their traditional formulation, and in a state space...... formulation. In the latter, noise enters at the level of the hidden states, as well as in the BOLD measurements themselves. A framework has been developed to allow approximate posterior distributions of model parameters to be learned from real fMRI data. This is accomplished with Markov chain Monte Carlo...

  11. Estimation of equivalent dose on the ends of hemodynamic physicians during neurological procedures

    International Nuclear Information System (INIS)

    Squair, Peterson L.; Souza, Luiz C. de; Oliveira, Paulo Marcio C. de

    2005-01-01

    The estimation of doses in the hands of physicists during hemodynamic procedures is important to verify the application of radiation protection related to the optimization and limit of dose, principles required by the Portaria 453/98 of Ministry of Health/ANVISA, Brazil. It was checked the levels of exposure of the hands of doctors during the use of the equipment in hemodynamic neurological procedures through dosimetric rings with thermoluminescent dosemeters detectors of LiF: Mg, Ti (TLD-100), calibrated in personal Dose equivalent HP (0.07). The average equivalent dose in the end obtained was 41.12. μSv per scan with an expanded uncertainty of 20% for k = 2. This value is relative to the hemodynamic Neurology procedure using radiological protection procedures accessible to minimize the dose

  12. Ultrasound investigation central hemodynamics as a method of assessment effective analgesia in children

    Directory of Open Access Journals (Sweden)

    K. Y. Dmytriieva

    2016-06-01

    Vinnitsa National Medical University M.I. Pirogov   Summary: The study was include in 23 children (12,4±1,2 years operated on for tumors of the retroperitoneal space (14 children, 61%, renal tumors (6 children, 26%, ovarian cancer (3 children, 13% showed that a comprehensive study of the reactions of pain behavior and central hemodynamics by ultrasonography showed that the use of the scheme KSME bupivacaine 0.3-0.4 mg / kg and a continuous infusion of drugs (fentanyl in a dose of 10 mcg/kg/h for postoperative pain relief leads to effective analgesia after traumatic operations and comprehensive ultrasound including color and spectral Doppler studies, is the main tool by enabling timely and accurately assess the condition of the central hemodynamics at different methods of analgesia.   Key words: central hemodynamics, ultrasound, anesthesia.

  13. Hemodynamic disturbances in cerebral ischemia; Correlation between positron emission tomographic and angiographic findings

    Energy Technology Data Exchange (ETDEWEB)

    Tenjin, Hiroshi; Ueda, Satoshi; Mizukawa, Norihiko; Imahori, Yoshio; Hino, Akihiko; Ohmori, Yoshio [Kyoto Prefectural Univ. of Medicine (Japan); Nakahashi, Hisamitsu

    1993-04-01

    Proper treatment of ischemic stroke requires better understanding of cerebral hemodynamic changes. The hemodynamic changes associated with ischemia were measured using positron emission tomography and related to angiographic findings in the subacute and chronic stages of 17 ischemia patients who showed symptoms of main trunk stenosis of the internal carotid artery system. The hemodynamic factors, cerebral blood flow, cerebral blood volume, cerebral metabolic rate for oxygen, oxygen extraction fraction, and flow/volume ratio, were measured in regions of interest determined from the angiographic stenosis (over 50%) and compared in each stage. The cerebral blood flow and flow/volume ratio in the territory downstream of the main trunk stenosis and cerebral metabolic rate for oxygen in the whole cortex were decreased in the subacute stage. In the chronic stage, cerebral blood flow and flow/volume ratio decreased mainly in borderzone areas. (author).

  14. Automatd assessment of the state of central hemodynamics using a radiocardioanalyser RCA 3-01

    International Nuclear Information System (INIS)

    Sivachenko, T.P.; Zozulya, A.A.; Sribnaya, A.F.; Ratmanskij, A.Yu.; Tishchenko, F.M.; Kurenya, A.G.; Krupka, I.N.; Kulagin, S.N.; Protsenko, A.S.

    1987-01-01

    The authors presented the results of a clinical use of a new radiocardioanalyzer RCA 3-01 (manufactured in the USSR) providing for automated measurements and computations of indices of the central hemodynamics during studies using a method of dilution of radioactive nuclides. The main technical potentialities of the device designed on the basis of microprocessor technology, were described. The authors also provided the results of automated computation of the circulating blood volume and the main hemodynamic indices in a group of patients. Values of the hemodynamic indices were shown to correspond to actual ones and comparable to control ones and clinical evidence. The comparison of automated processing with a manual method of calculation indicated a significant coincidence of index values. The clinical use of the radiocardioanalyzer RGA 3-01 for automated assessment of the indices of the cardiovascular system was shown to hold promise among various groups of patients

  15. Hemodynamic characterization of chronic bile duct-ligated rats: effect of pentobarbital sodium

    International Nuclear Information System (INIS)

    Lee, S.S.; Girod, C.; Braillon, A.; Hadengue, A.; Lebrec, D.

    1986-01-01

    Systemic and splanchnic hemodynamics of the chronic bile duct-ligated rat were characterized by radioactive microspheres. Conscious and pentobarbital sodium-anesthetized, bile duct-ligated and sham-operated rats had cardiac output and regional organ blood flows determined. The conscious bile duct-ligated rat compared with the sham-operated showed a hyperdynamic circulation with an increased cardiac output and portal tributary blood flow. Pentobarbital sodium anesthesia induced marked hemodynamic changes in both sham-operated and bile duct-ligated rats. The latter group was especially sensitive to its effects; thus, comparison of cardiac output and portal tributary blood flow between anesthetized bile duct-ligated and sham-operated rats showed no significant differences. The authors conclude that the rat with cirrhosis due to chronic bile duct ligation is an excellent model for hemodynamic investigations but should be studied in the conscious state, since pentobarbital sodium anesthesia eliminated the hyperdynamic circulation

  16. The numerical simulation study of hemodynamics of the new dense-mesh stent

    Science.gov (United States)

    Ma, Jiali; Yuan, Zhishan; Yu, Xuebao; Feng, Zhaowei; Miao, Weidong; Xu, Xueli; Li, Juntao

    2017-09-01

    The treatment of aortic aneurysm in new dense mesh stent is based on the principle of hemodynamic changes. But the mechanism is not yet very clear. This paper analyzed and calculated the hemodynamic situation before and after the new dense mesh stent implanting by the method of numerical simulation. The results show the dense mesh stent changed and impacted the blood flow in the aortic aneurysm. The changes include significant decrement of blood velocity, pressure and shear forces, while ensuring blood can supply branches, which means the new dense mesh stent's hemodynamic mechanism in the treatment of aortic aneurysm is clearer. It has very important significance in developing new dense mesh stent in order to cure aortic aneurysm.

  17. Weak correlations between hemodynamic signals and ongoing neural activity during the resting state

    Science.gov (United States)

    Winder, Aaron T.; Echagarruga, Christina; Zhang, Qingguang; Drew, Patrick J.

    2017-01-01

    Spontaneous fluctuations in hemodynamic signals in the absence of a task or overt stimulation are used to infer neural activity. We tested this coupling by simultaneously measuring neural activity and changes in cerebral blood volume (CBV) in the somatosensory cortex of awake, head-fixed mice during periods of true rest, and during whisker stimulation and volitional whisking. Here we show that neurovascular coupling was similar across states, and large spontaneous CBV changes in the absence of sensory input were driven by volitional whisker and body movements. Hemodynamic signals during periods of rest were weakly correlated with neural activity. Spontaneous fluctuations in CBV and vessel diameter persisted when local neural spiking and glutamatergic input was blocked, and during blockade of noradrenergic receptors, suggesting a non-neuronal origin for spontaneous CBV fluctuations. Spontaneous hemodynamic signals reflect a combination of behavior, local neural activity, and putatively non-neural processes. PMID:29184204

  18. Hemodynamic instability after pulmonary veins isolation in a patient with dual chamber pacemaker

    Science.gov (United States)

    Kiuchi, Márcio Galindo; Lobato, Guilherme Miglioli; Chen, Shaojie

    2017-01-01

    Abstract Introduction: The standard treatment of sinus node dysfunction (SND) is the pacemaker implantation, and the ideal methodology for the management of atrial fibrillation (AF) is rhythm control, but this is sometimes very hard to accomplish. For such actions, complete isolation of all pulmonary veins (PVI) is currently widely accepted as the best endpoint. Case Presentation: In this case, we report a female patient, 81 years old, with controlled hypertension, without coronary artery disease, bearer of bilateral knee replacement, and dual chamber pacemaker implanted 1.5 years ago owing to sinus node disease, presenting the following symptoms: presyncope episodes associated with sustained irregular palpitation tachycardia. The evaluation of the pacemaker-recorded episodes of atrial fibrillation, the echocardiogram-presented normal systolic function and measurements, as well as the resting myocardial scintigraphy and with drug use did not demonstrate ischemia and/or fibrosis. The patient was in use of valsartan 320 mg daily, amlodipine 10 mg daily, sotalol hydrochloride 120 mg 2 times daily, and dabigatran 110 mg 2 times daily. At the end of the PVI, the patient presented hemodynamic instability, with a decrease in heart rate to 30 bpm and invasive arterial blood pressure to 60/30 mmHg. The pericardial puncture was quickly carried out with the possibility of cardiac tamponade as the first hypothesis, but no pericardial effusion was found. Next, we detected acute capture loss from the ventricular pacemaker lead, unvarying with high voltage and pulse width, even with stable impedance, sense and keeping the same position visualized by fluoroscopy. And there was soon afterwards induction of sustained ventricular tachycardia degenerating to spontaneous ventricular fibrillation. Electrical cardioversion-defibrillation was performed with 200J, and the sinus rhythm was reestablished, but there was a dead short, and the pacemaker generator was burned and

  19. Evaluation of the hemodynamic effects of intravenous administration of ionic and nonionic contrast materials: implications for deriving physiologic measurements from computed tomography and digital cardiovascular imaging

    International Nuclear Information System (INIS)

    Higgins, C.B.; Berber, K.H.; Mattrey, R.F.; Slutsky, R.A.

    1982-01-01

    The effects of intravenous injection of an ionic contrast material (Renografin-76 [meglumine sodium diatrizoate]) on left ventricular pressure, internal diameter, and wall thickness, and on coronary and femoral hemodynamics were compared with those of a hydrolytically stable nonionic contrast material (iohexol). Renografin-76 caused drastic biphasic changes in left ventricular pressure and dp/dt (rate of change of left ventricular pressure), and moderate changes in end systolic dimension. Iohexol caused little or no change in left ventricular pressure and dimensions. In addition, Renografin-76 caused marked arterial hypotension and large increases in coronary and femoral blood lows, while iohexol caused no significant change in arterial pressure and coronary blood flow, and a mild increase in femoral blood flow. Based on these findings, it is concluded that iohexol is preferable to standard ionic contrast material for deriving basal physiologic information from computed tomographic and digital vascular studies

  20. Advisory group meeting on stable isotope labelled compounds in biomedical studies

    International Nuclear Information System (INIS)

    Vera Ruiz, H.; Parr, R.M.

    1985-11-01

    The programme of the meeting was restricted to topics involving applications of stable isotopes of the lighter elements (H, C, N, O). The current status of stable isotope techniques and applications in nutritional and biomedical studies, the applicability of these techniques in developing countries and the IAEA's future programmes on this topic were discussed

  1. Enriching stable isotopes: Alternative use for Urenco technology

    International Nuclear Information System (INIS)

    Rakhorst, H.; de Jong, P.G.T.; Dawson, P.D.

    1996-01-01

    The International Urenco Group utilizes a technologically advanced centrifuge process to enrich uranium in the fissionable isotope 235 U. The group operates plants in the United Kingdom, the Netherlands, and Germany and currently holds a 10% share of the multibillion dollar world enrichment market. In the early 1990s, Urenco embarked on a strategy of building on the company's uniquely advanced centrifuge process and laser isotope separation (LIS) experience to enrich nonradioactive isotopes colloquially known as stable isotopes. This paper summarizes the present status of Urenco's stable isotopes business

  2. Biomechanical and Hemodynamic Measures of Right Ventricular Diastolic Function: Translating Tissue Biomechanics to Clinical Relevance.

    Science.gov (United States)

    Jang, Sae; Vanderpool, Rebecca R; Avazmohammadi, Reza; Lapshin, Eugene; Bachman, Timothy N; Sacks, Michael; Simon, Marc A

    2017-09-12

    Right ventricular (RV) diastolic function has been associated with outcomes for patients with pulmonary hypertension; however, the relationship between biomechanics and hemodynamics in the right ventricle has not been studied. Rat models of RV pressure overload were obtained via pulmonary artery banding (PAB; control, n=7; PAB, n=5). At 3 weeks after banding, RV hemodynamics were measured using a conductance catheter. Biaxial mechanical properties of the RV free wall myocardium were obtained to extrapolate longitudinal and circumferential elastic modulus in low and high strain regions (E 1 and E 2 , respectively). Hemodynamic analysis revealed significantly increased end-diastolic elastance (E ed ) in PAB (control: 55.1 mm Hg/mL [interquartile range: 44.7-85.4 mm Hg/mL]; PAB: 146.6 mm Hg/mL [interquartile range: 105.8-155.0 mm Hg/mL]; P =0.010). Longitudinal E 1 was increased in PAB (control: 7.2 kPa [interquartile range: 6.7-18.1 kPa]; PAB: 34.2 kPa [interquartile range: 18.1-44.6 kPa]; P =0.018), whereas there were no significant changes in longitudinal E 2 or circumferential E 1 and E 2 . Last, wall stress was calculated from hemodynamic data by modeling the right ventricle as a sphere: stress=Pressure×radius2×thickness. RV pressure overload in PAB rats resulted in an increase in diastolic myocardial stiffness reflected both hemodynamically, by an increase in E ed , and biomechanically, by an increase in longitudinal E 1 . Modest increases in tissue biomechanical stiffness are associated with large increases in E ed . Hemodynamic measurements of RV diastolic function can be used to predict biomechanical changes in the myocardium. © 2017 The Authors. Published on behalf of the American Heart Association, Inc., by Wiley.

  3. Spontaneous hemodynamic oscillations during human sleep and sleep stage transitions characterized with near-infrared spectroscopy.

    Directory of Open Access Journals (Sweden)

    Tiina Näsi

    Full Text Available Understanding the interaction between the nervous system and cerebral vasculature is fundamental to forming a complete picture of the neurophysiology of sleep and its role in maintaining physiological homeostasis. However, the intrinsic hemodynamics of slow-wave sleep (SWS are still poorly known. We carried out 30 all-night sleep measurements with combined near-infrared spectroscopy (NIRS and polysomnography to investigate spontaneous hemodynamic behavior in SWS compared to light (LS and rapid-eye-movement sleep (REM. In particular, we concentrated on slow oscillations (3-150 mHz in oxy- and deoxyhemoglobin concentrations, heart rate, arterial oxygen saturation, and the pulsation amplitude of the photoplethysmographic signal. We also analyzed the behavior of these variables during sleep stage transitions. The results indicate that slow spontaneous cortical and systemic hemodynamic activity is reduced in SWS compared to LS, REM, and wakefulness. This behavior may be explained by neuronal synchronization observed in electrophysiological studies of SWS and a reduction in autonomic nervous system activity. Also, sleep stage transitions are asymmetric, so that the SWS-to-LS and LS-to-REM transitions, which are associated with an increase in the complexity of cortical electrophysiological activity, are characterized by more dramatic hemodynamic changes than the opposite transitions. Thus, it appears that while the onset of SWS and termination of REM occur only as gradual processes over time, the termination of SWS and onset of REM may be triggered more abruptly by a particular physiological event or condition. The results suggest that scalp hemodynamic changes should be considered alongside cortical hemodynamic changes in NIRS sleep studies to assess the interaction between the autonomic and central nervous systems.

  4. Variability of hemodynamic parameters in young healthy subjects with and without hypertensive family history

    International Nuclear Information System (INIS)

    Palombo, C.; Michelassi, C.; Ghione, S.

    1987-01-01

    In order to assess the short-term variability of the hemodynamic pattern in healthy normal subjects, Transcutaneous Aortovelography, a continuous wave Doppler technique, was performed in 17 normotensive males, 11 with and 6 without hypertensive family history and repeated after 30'. Reproducibility of measurements in the whole sample was comparable with previous observation reported in literature, but in the group with a positive family history of hypertension the reproducibility of most parameters was lower than in the other, suggesting the existence of a greater hemodynamic variability in normotensive offspring of hypertensive parents

  5. Hemodynamic and neuroendocrine responses to changes in sodium intake in compensated heart failure

    DEFF Research Database (Denmark)

    Damgaard, Morten; Norsk, Peter; Gustafsson, Finn

    2005-01-01

    inhibitors and beta-adrenoreceptor blockers. Therefore, we determined the hemodynamic and neuroendocrine responses to 1 wk of a low-sodium diet (70 mmol/day) and 1 wk of a high-sodium diet (250 mmol/day) in 12 HF patients and 12 age-matched controls in a randomized, balanced fashion. During steady......-state conditions, hemodynamic and neuroendocrine examinations were performed at rest and during bicycle exercise. In seated HF patients, high sodium intake increased body weight (1.6 +/- 0.4%), plasma volume (9 +/- 2%), cardiac index (14 +/- 6%), and stroke volume index (21 +/- 5%), whereas mean arterial pressure...

  6. Is there a specific hemodynamic effect in reflexology? A systematic review of randomized controlled trials.

    Science.gov (United States)

    Jones, Jenny; Thomson, Patricia; Irvine, Kathleen; Leslie, Stephen J

    2013-04-01

    Reflexology claims that the feet are representative of the body and that massage to specific points of the feet increases blood supply to "mapped" organs in the body. This review provides the first systematic evaluation of existing reflexology randomized controlled trials (RCTs) to determine whether there is any evidence to suggest the existence of a reflexology treatment-related hemodynamic effect; to examine whether reflexology researchers used study designs that systematically controlled for nonspecific effects in order to isolate this specific component; and to highlight some of the methodological challenges that need to be overcome to demonstrate specific and beneficial hemodynamic effects. Fifty-two RCTs of reflexology published from 1990 to September 2011 were initially retrieved. Cardiorespiratory Department, Highland Heartbeat Centre, Raigmore Hospital, Inverness. Adult subjects. Studies using reflexology foot massage techniques as the intervention versus sham reflexology treatment, simple foot massage, conventional treatment, or no treatment as the control were then selected. OUTCOME MEASURES included any hemodynamic parameter potentially involved in the regulation of circulating blood volume and flow, including heart rate and systolic and diastolic arterial blood pressure. Seven RCTs suggested that reflexology has an effect on selected cardiovascular parameters; however, five of these delivered the reflexology intervention as a whole complex treatment, with the data collector often delivering the intervention themselves. This systematic review found that although reflexology has been shown to have an effect on selected hemodynamic variables, the lack of methodological control for nonspecific general massage effects means that there is little convincing evidence at this time to suggest the existence of a specific treatment-related hemodynamic effect. Furthermore, the review found that few studies of reflexology controlled for nonspecific effects in order

  7. Vegetative and hemodynamic responses to stress in adolescents with constitutional-exogenous obesity and vascular dystonia of hypertensive type

    OpenAIRE

    Larina, N.

    2011-01-01

    We studied the characteristics of central hemodynamics and autonomic responses to cold and psycho-emotional test in adolescents with obesity and vascular dystonia of hypertensive type. Various options for the autonomic responses accompanied by changes in central hemodynamics as a function of body weight have been identified.

  8. Comparison of gabapentin, pregabalin and placebo as premedication for attenuation of hemodynamic response to laryngoscopy and endotracheal intubation

    Directory of Open Access Journals (Sweden)

    Alireza Mahoori

    2017-08-01

    Conclusion: Oral gabapentin premedication is effective for control of hemodynamic pressor response of laryngoscopy and tracheal intubation. The study data showed that the pregabalin have the same effect. Pregabalin and gabapentin are both useful and safe for control of hemodynamic pressor response as premedication.

  9. 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.

  10. [Current Treatment of Stable Angina].

    Science.gov (United States)

    Toggweiler, Stefan; Jamshidi, Peiman; Cuculi, Florim

    2015-06-17

    Current therapy for stable angina includes surgical and percutaneous revascularization, which has been improved tremendously over the last decades. Smoking cessation and regular exercise are the cornerstone for prevention of further cerebrovascular events. Medical treatment includes treatment of cardiovascular risk factors and antithrombotic management, which can be a challenge in some patients. Owing to the fact the coronary revascularization is readily accessible these days in many industrialized countries, the importance of antianginal therapy has decreased over the past years. This article presents a contemporary overview of the management of patients with stable angina in the year 2015.

  11. Status epilepticus

    NARCIS (Netherlands)

    Hensiek, AE; Absalom, Anthony

    2006-01-01

    Status epilepticus is defined as epileptic activity that continues for more than 30 minutes as a single seizure or as recurrent seizures without inter-ictal return of consciousness. The seizure activity is usually classified as partial or generalized. Although status epilepticus is an uncommon

  12. Pulmonary hemodynamic profile in chronic obstructive pulmonary disease

    Directory of Open Access Journals (Sweden)

    Portillo K

    2015-07-01

    Full Text Available Karina Portillo,1 Yolanda Torralba,1,2 Isabel Blanco,1,2 Felip Burgos,1,2 Roberto Rodriguez-Roisin,1,2 Jose Rios,3 Josep Roca,1,2 Joan A Barberà1,21Department of Pulmonary Medicine, Hospital Clínic-Institut d’Investigacions Biomèdiques August Pi iSunyer (IDIBAPS, University of Barcelona, Barcelona, Spain; 2Centro de Investigación Biomédica en Red de Enfermedades Respiratorias (CIBERES, Madrid, Spain; 3Biostatistics and Data Management Core Facility, Hospital Clínic-Institut d’Investigacions Biomèdiques August Pi iSunyer (IDIBAPS, Biostatistics Unit, School of Medicine, Universitat Autònoma de Barcelona, Barcelona, SpainIntroduction: Few data are available in regards to the prevalence of pulmonary hypertension (PH in the broad spectrum of COPD. This study was aimed at assessing the prevalence of PH in a cohort of COPD patients across the severity of airflow limitation, and reporting the hemodynamic characteristics at rest and during exercise.Methods: We performed a retrospective analysis on COPD patients who underwent right-heart catheterization in our center with measurements obtained at rest (n=139 and during exercise (n=85. PH was defined as mean pulmonary artery pressure (mPAP ≥25 mmHg and pulmonary capillary wedge pressure <15 mmHg. Exercise-induced PH (EIPH was defined by a ratio of ∆mPAP/∆cardiac output >3.Results: PH was present in 25 patients (18%. According to the Global Initiative for Chronic Obstructive Lung Disease (GOLD classification, PH prevalence in GOLD 2 was 7% (3 patients; 25% (14 patients in GOLD 3; and 22% (8 patients in GOLD 4. Severe PH (mPAP ≥35 mmHg was identified in four patients (2.8%. Arterial partial oxygen pressure was the outcome most strongly associated with PH (r=-0.29, P<0.001. EIPH was observed in 60 patients (71% and had a similar prevalence in both GOLD 2 and 3, and was present in all GOLD 4 patients. Patients with PH had lower cardiac index during exercise than patients without PH (5

  13. Characteristics of intraoperative abnormal hemodynamics during resection of an intra-fourth ventricular tumor located on the dorsal medulla oblongata.

    Science.gov (United States)

    Ideguchi, Makoto; Kajiwara, Koji; Yoshikawa, Koichi; Sadahiro, Hirokazu; Nomura, Sadahiro; Fujii, Masami; Suzuki, Michiyasu

    2013-01-01

    Abnormal hemodynamics during extirpation of a para-medulla oblongata (MO) tumor is common and may be associated with direct vagal stimulation of the medullary circuit. However, resection of tumors on the dorsal MO may also induce hemodynamic instability without direct vagal stimulus. The objective of this study was to examine the characteristics of hemodynamic instability unrelated to vagal stimulus during dissection of an intra-fourth ventricular tumor with attachment to the dorsal MO. A retrospective analysis was performed in 13 patients. Abnormal hemodynamics were defined as a > 20% change from the means of the intraoperative mean arterial pressure (MAP) and heart rate (HR). Relationships of intraoperative hemodynamics were evaluated with various parameters, including the volume of the MO. Six patients (46.2%) had intraoperative hypertension during separation of the tumor bulk from the dorsal MO. The maximum MAP and HR in these patients were significantly greater than those in patients with normal hemodynamics (116.0 ± 18.0 mmHg versus 85.6 ± 6.5 mmHg; 124.3 ± 22.8 bpm versus 90.5 ± 14.7 bpm). All six cases with abnormal hemodynamics showed hemodynamic fluctuation during separation of the tumor bulk from the dorsal MO. The preoperative volume of the MO in these patients was 1.11 cc less than that in patients with normal hemodynamics, but the volume after tumor resection was similar in the two groups (5.23 cc and 5.12 cc). This suggests that the MO was compressed by the conglutinate tumor bulk, with resultant fluctuation of hemodynamics. Recognition of and preparation for this phenomenon are important for surgery on a tumor located on the dorsal MO.

  14. Possibility of stable quark stars

    International Nuclear Information System (INIS)

    Bowers, R.L.; Gleeson, A.M.; Pedigo, R.D.

    1976-08-01

    A recent zero temperature equation of state which contains quark-partons separated from conventional baryons by a phase transition is used to investigate the stability of quark stars. The sensitivity to the input physics is also considered. The conclusions, which are found to be relatively model independent, indicate that a separately identifiable class of stable objects called quark stars does not exist

  15. Radiation-stable polyolefin compositions

    International Nuclear Information System (INIS)

    Rekers, J.W.

    1986-01-01

    This invention relates to compositions of olefinic polymers suitable for high energy radiation treatment. In particular, the invention relates to olefinic polymer compositions that are stable to sterilizing dosages of high energy radiation such as a gamma radiation. Stabilizers are described that include benzhydrol and benzhydrol derivatives; these stabilizers may be used alone or in combination with secondary antioxidants or synergists

  16. Hemodynamic, biological, and right ventricular functional changes following intraatrial shunt repair in patients with flow-induced pulmonary hypertension.

    Science.gov (United States)

    Hsu, Chih-Hsin; Roan, Jun-Neng; Wang, Jieh-Neng; Huang, Chien-Chi; Shih, Chao-Jung; Chen, Jyh-Hong; Wu, Jing-Ming; Lam, Chen-Fuh

    2017-07-01

    Atrial septal defects may result in pulmonary hypertension and right heart remodeling. We analyzed improvements in patients with flow-induced pulmonary hypertension and the activation of endothelial progenitor cells after flow reduction. This prospective cohort study included 37 patients who were admitted for an occluder implantation. Blood samples were collected before and after the procedure. We determined the number of endothelial progenitor cells in outgrowth colonies and serum Hsp27 concentrations. Daily performance and cardiothoracic ratio were reevaluated later. Closure of the defect significantly reduced the pulmonary pressure and B-type natriuretic peptide levels. The cardiothoracic ratio and daily performance status also improved. The number of endothelial progenitor cell outgrowth colony-forming units significantly increased and was positively correlated with daily performance. In patients with enhanced colony formation, Hsp27 levels were significantly increased. The implantation of an occluder successfully improved hemodynamic, right ventricular, and daily performance. Qualitative enhancement of colony formation for endothelial progenitor cells was also noted and positively correlated with daily performance. Closure of defects may serve as a valid, reliable model to obtain a deeper understanding of the modulation of endothelial progenitor cell activity and its relationship with pulmonary hypertension prognosis. © 2017 Wiley Periodicals, Inc.

  17. Effects of irradiation on the pulmonary hemodynamics and the pulmonary vascular permeability

    International Nuclear Information System (INIS)

    Ohkuda, Kazuhiro; Watanabe, Shinkichi; Okada, Shinichiroh

    1982-01-01

    In 4 sheeps, base lines of hemodynamics and lymph dynamics were observed for 2 hours, and then 1,000 rad of 60 Co was irradiated to the inferior lobes of the lung. Pulmonary hemodynamics and lymph dynamics were continuously observed, and water and protein permeability of the irradiated pulmonary vessels was evaluated. In 4 control sheeps, no change in pulmonary hemodynamics and lymph dynamics was noted. In the irradiated group, there was no remarkable change in pulmonary hemodynamics for 6 to 8 hours after 60 Co irradiation. Pulmonary lymph flow began to increase 2 hours after irradiation to about 1.7 times the base line level after 4 hours. The increase in pulmonary lymph flow was accompanied by decrease in plasma protein concentration and increase in protein concentration of the lung lymph, resulting in an apparent increase in the ratio of lymph/plasma protein concentration. Water and protein leak from the pulmonary vessels increased. A photomicroscopic observation revealed dilatation of the lymphatic vessels in the lung interstice and a mild pulmonary interstitial edema. Vascular damage, especially due to increased water and protein permeability of the lung capillary vessels, occurred immediately after 60 Co irradiation. (Ueda, J.)

  18. Hemodynamic and morphological characteristics of unruptured posterior communicating artery aneurysms with oculomotor nerve palsy.

    Science.gov (United States)

    Lv, Nan; Yu, Ying; Xu, Jinyu; Karmonik, Christof; Liu, Jianmin; Huang, Qinghai

    2016-08-01

    OBJECT Unruptured posterior communicating artery (PCoA) aneurysms with oculomotor nerve palsy (ONP) have a very high risk of rupture. This study investigated the hemodynamic and morphological characteristics of intracranial aneurysms with high rupture risk by analyzing PCoA aneurysms with ONP. METHODS Fourteen unruptured PCoA aneurysms with ONP, 33 ruptured PCoA aneurysms, and 21 asymptomatic unruptured PCoA aneurysms were included in this study. The clinical, morphological, and hemodynamic characteristics were compared among the different groups. RESULTS The clinical characteristics did not differ among the 3 groups (p > 0.05), whereas the morphological and hemodynamic analyses showed that size, aspect ratio, size ratio, undulation index, nonsphericity index, ellipticity index, normalized wall shear stress (WSS), and percentage of low WSS area differed significantly (p PCoA aneurysms with ONP demonstrated a distinctive morphological-hemodynamic pattern that was significantly different compared with asymptomatic unruptured PCoA aneurysms and was similar to ruptured PCoA aneurysms. The larger size, more irregular shape, and lower WSS might be related to the high rupture risk of PCoA aneurysms.

  19. Effects of radiation, burn and combined radiation-burn injury on hemodynamics

    International Nuclear Information System (INIS)

    Ye Benlan; Cheng Tianming; Xiao Jiasi

    1996-01-01

    Changes in hemodynamics after radiation, burn and combined radiation burn injury within eight hours post injury were studied. The results indicate: (1) Shock of rats in the combined injury group is more severe than that in the burn group. One of the reasons is that the blood volume in the combined injury group is less than that in the burn group. Radiation injury plays an important role in this effect, which enhances the increase in vascular permeability and causes the loss of plasma. (2) Decrease in cardiac output and stroke work and increase in vascular resistance in the combined radiation burn group are more drastic than those in the burn group, which may cause and enhance shock. Replenishing fluid is useful for recovery of hemodynamics. (3) Rb uptake is increased in the radiation group which indicates that compensated increase of myocardial nutritional blood flow may take place before the changes of hemodynamics and shock. Changes of Rb uptake in the combined injury group is different from that in the radiation groups and in the burn group. The results also suggest that changes of ion channel activities may occur to a different extent after injury. (4) Verapamil is helpful to the recovery of hemodynamics post injury. It is better to combine verapamil with replenishing fluid

  20. Augmentation of sensory-evoked hemodynamic response in an early Alzheimer's disease mouse model.

    Science.gov (United States)

    Kim, Jinho; Jeong, Yong

    2013-01-01

    Based on enlarged blood oxygen level-dependent (BOLD) responses in cognitively normal subjects at risk for Alzheimer's disease (AD), compensatory neuronal hyperactivation has been proposed as an early marker for diagnosis of AD. The BOLD response results from neurovascular coupling, i.e., hemodynamic response induced by neuronal activity. However, there has been no evidence of task-induced increases in hemodynamic response in animal models of AD. Here, we observed an augmented hemodynamic response pattern in a transgenic AβPP(SWE)/PS1ΔE9 mouse model of AD using three in vivo imaging methods: intrinsic optical signal imaging, multi-photon laser scanning microscopy, and laser Doppler flowmetry. Sensory stimulation resulted in augmented and prolonged hemodynamic responses in transgenic mice evidenced by changes in total, oxygenated, and deoxygenated hemoglobin concentration. This difference between transgenic and wild-type mice was significant at 7 months of age when amyloid plaques and cerebral amyloid angiopathy had developed but not at younger or older ages. Correspondingly, sensory stimulation-induced pial arteriole diameter was also augmented and prolonged in transgenic mice at 7 months of age. Cerebral blood flow response in transgenic mice was augmented but not prolonged. These results are consistent with the existence of BOLD signal hyperactivation in non-demented AD-risk human subjects, supporting its potential use as an early diagnostic marker of AD.

  1. Alpha-adducin Gly460Trp polymorphism and renal hemodynamics in essential hypertension

    NARCIS (Netherlands)

    Beeks, Esther; van der Klauw, Melanie M; Kroon, Abraham A; Spiering, Wilko; Fuss-Lejeune, Monique J M J; de Leeuw, Peter W

    2004-01-01

    Previous studies have shown an association between the alpha-adducin Gly460Trp polymorphism and salt-sensitive hypertension. Not much is known about the effects of the variants of this polymorphism on renal hemodynamics and function. Therefore, we performed the present study to investigate the

  2. Comparison of hemodynamic effects of lidocaine, prilocaine and mepivacaine solutions without vasoconstrictor in hypertensive patients

    Directory of Open Access Journals (Sweden)

    Bahadir Ezmek

    2010-08-01

    Full Text Available OBJECTIVE: Local anesthetic solutions with vasoconstrictors are not contraindicated in hypertensive patients, but due to their hemodynamic effects, local anesthetics without vasoconstrictors are mainly preferred by the clinicians. The aim of this study was to compare hemodynamic effects of three different local anesthetics without vasoconstrictors during tooth extraction in hypertensive patients. MATERIAL AND METHODS: Sixty-five mandibular molars and premolars were extracted in 60 hypertensive patients (29 females and 31 males; mean age: 66.95 ± 10.87 years; range: 38 to 86 years old. Inferior alveolar and buccal nerve blocks were performed with 2% lidocaine hydrochloride (HCl, 2% prilocaine HCl or 3% mepivacaine HCl without vasoconstrictor. Hemodynamic parameters namely systolic blood pressure (SBP, diastolic blood pressure (DBP, mean arterial pressure (MAP, heart rate (HR, saturation rate (SR, rate pressure product (RPP and pressure rate quotient (PRQ were investigated before and at different intervals after anesthetic injection. RESULTS: The hemodynamic effects of the three agents were similar to each other, although some significance was observed for DBP, MAP, RPP and PRQ values in the lidocaine, prilocaine and mepivacaine groups. CONCLUSION: Lidocaine, prilocaine and mepivacaine solutions without vasoconstrictor can be safely used in hypertensive patients. It is advisable that dental practitioners select anesthetic solutions for hypertensive patients considering their cardiovascular effects in order to provide patient comfort and safety.

  3. Echographic and hemodynamic parameters in patients with hepatic cirrhosis and portal hypertension

    International Nuclear Information System (INIS)

    Rikhsieva, L.Eh.; Akhmedzhanova, Sh.Sh.; Myasnik, B.N.; Khodzhibekov, M.Kh.

    1989-01-01

    The efficiency of combined echoradionuclide investigation for the identification of the severity of portal hypertension and the determination of clear-cut criteria for the differentiation of stages of portal hypertension with reference to functional potentials of renal hemodynamics and systemic circulation at large is demonstrated

  4. Neuronal inhibition and excitation, and the dichotomic control of brain hemodynamic and oxygen responses

    DEFF Research Database (Denmark)

    Lauritzen, Martin; Mathiesen, Claus; Schaefer, Katharina

    2012-01-01

    under most conditions correlate to excitation of inhibitory interneurons, but there are important exceptions to that rule as described in this paper. Thus, variations in the balance between synaptic excitation and inhibition contribute dynamically to the control of metabolic and hemodynamic responses...

  5. Induced Hypothermia Does Not Harm Hemodynamics after Polytrauma: A Porcine Model

    Science.gov (United States)

    Mommsen, Philipp; Pfeifer, Roman; Mohr, Juliane; Ruchholtz, Steffen; Flohé, Sascha; Fröhlich, Matthias; Keibl, Claudia; Seekamp, Andreas; Witte, Ingo

    2015-01-01

    Background. The deterioration of hemodynamics instantly endangers the patients' life after polytrauma. As accidental hypothermia frequently occurs in polytrauma, therapeutic hypothermia still displays an ambivalent role as the impact on the cardiopulmonary function is not yet fully understood. Methods. We have previously established a porcine polytrauma model including blunt chest trauma, penetrating abdominal trauma, and hemorrhagic shock. Therapeutic hypothermia (34°C) was induced for 3 hours. We documented cardiovascular parameters and basic respiratory parameters. Pigs were euthanized after 15.5 hours. Results. Our polytrauma porcine model displayed sufficient trauma impact. Resuscitation showed adequate restoration of hemodynamics. Induced hypothermia had neither harmful nor major positive effects on the animals' hemodynamics. Though heart rate significantly decreased and mixed venous oxygen saturation significantly increased during therapeutic hypothermia. Mean arterial blood pressure, central venous pressure, pulmonary arterial pressure, and wedge pressure showed no significant differences comparing normothermic trauma and hypothermic trauma pigs during hypothermia. Conclusions. Induced hypothermia after polytrauma is feasible. No major harmful effects on hemodynamics were observed. Therapeutic hypothermia revealed hints for tissue protective impact. But the chosen length for therapeutic hypothermia was too short. Nevertheless, therapeutic hypothermia might be a useful tool for intensive care after polytrauma. Future studies should extend therapeutic hypothermia. PMID:26170533

  6. The hemodynamic response of the alpha rhythm: an EEG/fMRI study.

    NARCIS (Netherlands)

    de Munck, J.C.; Goncalves, S.I.; Huijboom, L.; Kuijer, J.P.; Pouwels, P.J.; Heethaar, R.M.; Lopes da Silva, F.H.

    2007-01-01

    EEG was recorded during fMRI scanning of 16 normal controls in resting condition with eyes closed. Time variations of the occipital alpha band amplitudes were correlated to the fMRI signal variations to obtain insight into the hemodynamic correlates of the EEG alpha activity. Contrary to earlier

  7. Induced Hypothermia Does Not Harm Hemodynamics after Polytrauma: A Porcine Model

    Directory of Open Access Journals (Sweden)

    Matthias Weuster

    2015-01-01

    Full Text Available Background. The deterioration of hemodynamics instantly endangers the patients’ life after polytrauma. As accidental hypothermia frequently occurs in polytrauma, therapeutic hypothermia still displays an ambivalent role as the impact on the cardiopulmonary function is not yet fully understood. Methods. We have previously established a porcine polytrauma model including blunt chest trauma, penetrating abdominal trauma, and hemorrhagic shock. Therapeutic hypothermia (34°C was induced for 3 hours. We documented cardiovascular parameters and basic respiratory parameters. Pigs were euthanized after 15.5 hours. Results. Our polytrauma porcine model displayed sufficient trauma impact. Resuscitation showed adequate restoration of hemodynamics. Induced hypothermia had neither harmful nor major positive effects on the animals’ hemodynamics. Though heart rate significantly decreased and mixed venous oxygen saturation significantly increased during therapeutic hypothermia. Mean arterial blood pressure, central venous pressure, pulmonary arterial pressure, and wedge pressure showed no significant differences comparing normothermic trauma and hypothermic trauma pigs during hypothermia. Conclusions. Induced hypothermia after polytrauma is feasible. No major harmful effects on hemodynamics were observed. Therapeutic hypothermia revealed hints for tissue protective impact. But the chosen length for therapeutic hypothermia was too short. Nevertheless, therapeutic hypothermia might be a useful tool for intensive care after polytrauma. Future studies should extend therapeutic hypothermia.

  8. [Role of cerebral hemodynamics in the mechanism of development of acquired myopia in schoolchildren].

    Science.gov (United States)

    Iastrebtseva, T A; Demidova, T E; Polikarpova, V E

    2008-01-01

    Rheoencephalography was used to study cerebral venous circulation in 199 schoolchildren aged 12-15 years who had emmetropia, pseudomyopia, and myopia. Tonometry was carried out in 39 persons. Cerebral venous hemodynamic dysfunction was more frequently encountered in schoolchildren with myopia than in those with emmetropia. Intraocular pressure was significantly higher only in schoolchildren with high myopia than in the controls.

  9. A Novel Technique for Identifying Patients with ICU Needs Using Hemodynamic Features

    Directory of Open Access Journals (Sweden)

    A. Jalali

    2012-01-01

    Full Text Available Identification of patients requiring intensive care is a critical issue in clinical treatment. The objective of this study is to develop a novel methodology using hemodynamic features for distinguishing such patients requiring intensive care from a group of healthy subjects. In this study, based on the hemodynamic features, subjects are divided into three groups: healthy, risky and patient. For each of the healthy and patient subjects, the evaluated features are based on the analysis of existing differences between hemodynamic variables: Blood Pressure and Heart Rate. Further, four criteria from the hemodynamic variables are introduced: circle criterion, estimation error criterion, Poincare plot deviation, and autonomic response delay criterion. For each of these criteria, three fuzzy membership functions are defined to distinguish patients from healthy subjects. Furthermore, based on the evaluated criteria, a scoring method is developed. In this scoring method membership degree of each subject is evaluated for the three classifying groups. Then, for each subject, the cumulative sum of membership degree of all four criteria is calculated. Finally, a given subject is classified with the group which has the largest cumulative sum. In summary, the scoring method results in 86% sensitivity, 94.8% positive predictive accuracy and 82.2% total accuracy.

  10. Journal of Clinical Monitoring and Computing 2016 end of year summary : cardiovascular and hemodynamic monitoring

    NARCIS (Netherlands)

    Saugel, Bernd; Bendjelid, Karim; Critchley, Lester A.; Rex, Steffen; Scheeren, Thomas W. L.

    The assessment and optimization of cardiovascular and hemodynamic variables is a mainstay of patient management in the care for critically ill patients in the intensive care unit (ICU) or the operating room (OR). It is, therefore, of outstanding importance to meticulously validate technologies for

  11. 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.

  12. Thoracic Aorta 3D Hemodynamics in Pediatric and Young Adult Patients With Bicuspid Aortic Valve

    NARCIS (Netherlands)

    Allen, Bradley D.; van Ooij, Pim; Barker, Alex J.; Carr, Maria; Gabbour, Maya; Schnell, Susanne; Jarvis, Kelly B.; Carr, James C.; Markl, Michael; Rigsby, Cynthia; Robinson, Joshua D.

    2015-01-01

    Background: To evaluate the 3D hemodynamics in the thoracic aorta of pediatric and young adult bicuspid aortic valve (BAV) patients. Methods: 4D flow MRI was performed in 30 pediatric and young adult BAV patients (age: 13.9 +/- 4.4 (range: [3.4, 20.7]) years old, M:F = 17:13) as part of this

  13. Hemodynamic effects of iodixanol and iohexol during ventriculography in patients with compromised left ventricular function

    NARCIS (Netherlands)

    Bergstra, A; van Dijk, RB; Brekke, O; Orozco, L; den Heijer, P; Crijns, HJGM

    A crossover study was performed to compare the hemodynamic effects of the isoosmolar contrast agent iodixanol (Visipaque(R)) 320 mg I/ml to those of the low-osmolar iohexol (Omnipaque(R)) 350 mg I/ml. The main hypothesis was that iodixanol and iohexol would affect left ventricular end-diastolic

  14. The hemodynamic repercussions of the autonomic modulations in growth-restricted fetuses

    Directory of Open Access Journals (Sweden)

    Igor Victorovich Lakhno

    2017-12-01

    Conclusion: Fetal heart rate pattern was influenced by maternal and fetal autonomic tone. Maternal cardiovascular oscillations were reflected in the umbilical circulation in healthy pregnancy Fetal distress was featured by sympathetic overactivity and the reduction of vagal tone. Such autonomic modulations was manifested by the decelerative pattern of CTG and deteriorated umbilical hemodynamics.

  15. Serial hemodynamic measurement in normal pregnancy, preeclampsia, and intrauterine growth restriction

    NARCIS (Netherlands)

    Rang, Saskia; van Montfrans, Gert A.; Wolf, Hans

    2008-01-01

    OBJECTIVE: The study hypothesis was that hemodynamic measurements in conjunction with uterine artery Doppler could enable selection of women at risk for the development of preeclampsia or fetal growth restriction. STUDY DESIGN: Systolic (SBP) and diastolic blood pressure, heart rate (RR), cardiac

  16. Circadian monitoring of ECG findings and central hemodynamics in cancer patients at radiotherapy planning

    International Nuclear Information System (INIS)

    Tolkachov, Yu.A.; Vasil'jev, L.Ya.; Svinarenko, A.V.

    2003-01-01

    Fifty-seven patients aged 34-67 were examined. Considerable circadian fluctuations of main hemodynamic and ECG parameters, which can suggest disorders of circadian rhythms or limit chemoradiotherapy were not noticed in different cancers. Functional criteria of biorhythm state require further investigation

  17. Impact of metabolic, hemodynamic and inflammatory factors on target organ damage in healthy subjects

    DEFF Research Database (Denmark)

    Blicher, M.; Kruger, R.; Olesen, Thomas Bastholm

    2015-01-01

    Objective: We wanted to test the impact of metabolic, hemodynamic and inflammatory factors on target organ damage (TOD) defined as cardiac hypertrophy, atherosclerosis, arterioclerosis and microvascular damage. Design and method: In a population based cohort study of 2115 healthy subjects (1049...... associated to hypertrophy, arteriosclerosis and microvascular damage in healthy subjects....

  18. Differences in postprandial hemodynamic response on a high protein versus a high carbohydrate diet

    NARCIS (Netherlands)

    Dopheide, J.; Geleijnse, J.M.; Bakker, S.J.L.; Brink, E.J.; Baak, van M.A.

    2011-01-01

    Objective: Several intervention trials have shown that diet composition affects blood pressure (BP). In this study we focused on postprandial hemodynamic changes on a high carbohydrate versus a high protein diet. Design and Method: In this randomized double-blind parallel group study, 53 adult

  19. The effect of metabolic control on hemodynamics in short-term insulin-dependent diabetic patients

    DEFF Research Database (Denmark)

    Mathiesen, E R; Hilsted, J; Feldt-Rasmussen, B

    1985-01-01

    Hemodynamics variables (heart rate, arterial blood pressure, cardiac output, hepato-splanchnic blood flow, forearm blood flow, and plasma catecholamines) were measured during good (median blood glucose 4.7 mmol/L) and poor (median blood glucose 16.3 mmol/L) metabolic control in eight young, short...

  20. A New Framework for the Assessment of Cerebral Hemodynamics Regulation in Neonates Using NIRS

    NARCIS (Netherlands)

    Caicedo, Alexander; Alderliesten, Thomas; Naulaers, Gunnar; Lemmers, Petra; van Bel, Frank; Van Huffel, Sabine

    2016-01-01

    We present a new framework for the assessment of cerebral hemodynamics regulation (CHR) in neonates using near-infrared spectroscopy (NIRS). In premature infants, NIRS measurements have been used as surrogate variables for cerebral blood flow (CBF) in the assessment of cerebral autoregulation (CA).

  1. Characterization of Hemodynamics in Patients with Idiopathic and Thromboembolic Pulmonary Hypertension

    Directory of Open Access Journals (Sweden)

    Carmelle V. Remillard

    2008-01-01

    Full Text Available Demographic and hemodynamic data from patients with idiopathic pulmonary arterial hypertension (IPAH and chronic thromboembolic pulmonary hypertension (CTEPH have not been systematically characterized to identify differences related to gender, age, race, disease severity, and drug response. Our goal was to define the distribution and relation of IPAH and CTEPH based on these criteria. Hemodynamic and demographic data from 242 IPAH patients and 90 CTEPH patients were collected and compared. IPAH incidence was greater in women, but men had a higher basal mean pulmonary arterial pressure (mPAP. mPAP was comparable among all IPAH ethnic groups. IPAH patients with no history of fenfluramine-phentermine use had a higher mPAP than users. Exercise-induced IPAH was apparent in 14.5% of IPAH patients. Only 9% of IPAH patients responded to inhaled nitric oxide with a ≥20% decrease in mPAP. Compared to CTEPH patients, mPAP was greater but average age of diagnosis was lower in IPAH patients. mPAP negatively correlated with age of diagnosis in IPAH patients only. These results indicate that elevated CO is not the main determinant of mPAP in both IPAH and CTEPH patients. However, the two patient groups differ in terms of their demographic and hemodynamic distributions, and according to the correlation between mPAP and other clinical hemodynamics and demographics.

  2. Application of a user-friendly comprehensive circulatory model for estimation of hemodynamic and ventricular variables

    NARCIS (Netherlands)

    Ferrari, G.; Kozarski, M.; Gu, Y. J.; De Lazzari, C.; Di Molfetta, A.; Palko, K. J.; Zielinski, K.; Gorczynska, K.; Darowski, M.; Rakhorst, G.

    2008-01-01

    Purpose: Application of a comprehensive, user-friendly, digital computer circulatory model to estimate hemodynamic and ventricular variables. Methods: The closed-loop lumped parameter circulatory model represents the circulation at the level of large vessels. A variable elastance model reproduces

  3. Effect of breath holding on cerebrovascular hemodynamics in normal pregnancy and preeclampsia

    NARCIS (Netherlands)

    van Veen, Teelkien R.; Panerai, Ronney B.; Haeri, Sina; Zeeman, Gerda G.; Belfort, Michael A.

    2015-01-01

    Preeclampsia (PE) is associated with endothelial dysfunction and impaired autonomic function, which is hypothesized to cause cerebral hemodynamic abnormalities. Our aim was to test this hypothesis by estimating the difference in the cerebrovascular response to breath holding (BH; known to cause

  4. Effects of midazolam and morphine on cerebral oxygenation and hemodynamics in ventilated premature infants.

    NARCIS (Netherlands)

    Velden, A.A.E.M. van der; Hopman, J.C.W.; Klaessens, J.H.G.M.; Feuth, A.B.; Sengers, R.C.A.; Liem, K.D.

    2006-01-01

    BACKGROUND: Midazolam sedation and morphine analgesia are commonly used in ventilated premature infants. OBJECTIVES: To evaluate the effects of midazolam versus morphine infusion on cerebral oxygenation and hemodynamics in ventilated premature infants. METHODS: 11 patients (GA 26.6-33.0 weeks, BW

  5. 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.

  6. Laparoscopic cholecystectomy using abdominal wall retraction. Hemodynamics and gas exchange, a comparison with conventional pneumoperitoneum

    NARCIS (Netherlands)

    Meijer, D. W.; Rademaker, B. P.; Schlooz, S.; Bemelman, W. A.; de Wit, L. T.; Bannenberg, J. J.; Stijnen, T.; Gouma, D. F.

    1997-01-01

    BACKGROUND: Disadvantages related to CO2 pneumoperitoneum have led to development of the abdominal wall retractor (AWR), a device designed to facilitate laparoscopic surgery without conventional pneumoperitoneum (15 mmHg CO2). We investigated the effects of the AWR on hemodynamics and gas exchange

  7. Physiology of school burnout in medical students: Hemodynamic and autonomic functioning

    Directory of Open Access Journals (Sweden)

    Ross W. May

    2016-09-01

    Full Text Available This study investigated the relationship between burnout and hemodynamic and autonomic functioning in both medical students (N = 55 and premedical undergraduate students (N = 77. Questionnaires screened for health related issues and assessed school burnout and negative affect symptomatology (anxiety and depression. Continuous beat-to-beat blood pressure (BP through finger plethysmography and electrocardiogram (ECG monitoring was conducted during conditions of baseline and cardiac stress induced via the cold pressor task to produce hemodynamic, heart rate variability, and blood pressure variability indices. Independent sample t-tests demonstrated that medical students had significantly higher school burnout scores compared to their undergraduate counterparts. Controlling for age, BMI, anxiety and depressive symptoms, multiple regression analyses indicated that school burnout was a stronger predictor of elevated hemodynamics (blood pressure, decreased heart rate variability, decreased markers of vagal activity and increased markers of sympathetic tone at baseline for medical students than for undergraduates. Analyses of physiological values collected during the cold pressor task indicated greater cardiac hyperactivity for medical students than for undergraduates. The present study supports previous research linking medical school burnout to hemodynamic and autonomic functioning, suggests biomarkers for medical school burnout, and provides evidence that burnout may be implicated as a physiological risk factor in medical students. Study limitations and potential intervention avenues are discussed.

  8. Prevention of hemodynamic and vascular albumin filtration changes in diabetic rats by aldose reductase inhibitors

    International Nuclear Information System (INIS)

    Tilton, R.G.; Chang, K.; Pugliese, G.; Eades, D.M.; Province, M.A.; Sherman, W.R.; Kilo, C.; Williamson, J.R.

    1989-01-01

    This study investigated hemodynamic changes in diabetic rats and their relationship to changes in vascular albumin permeation and increased metabolism of glucose to sorbitol. The effects of 6 wk of streptozocin-induced diabetes and three structurally different inhibitors of aldose reductase were examined on (1) regional blood flow (assessed with 15-microns 85Sr-labeled microspheres) and vascular permeation by 125I-labeled bovine serum albumin (BSA) and (2) glomerular filtration rate (assessed by plasma clearance of 57Co-labeled EDTA) and urinary albumin excretion (determined by radial immunodiffusion assay). In diabetic rats, blood flow was significantly increased in ocular tissues (anterior uvea, posterior uvea, retina, and optic nerve), sciatic nerve, kidney, new granulation tissue, cecum, and brain. 125I-BSA permeation was increased in all of these tissues except brain. Glomerular filtration rate and 24-h urinary albumin excretion were increased 2- and 29-fold, respectively, in diabetic rats. All three aldose reductase inhibitors completely prevented or markedly reduced these hemodynamic and vascular filtration changes and increases in tissue sorbitol levels in the anterior uvea, posterior uvea, retina, sciatic nerve, and granulation tissue. These observations indicate that early diabetes-induced hemodynamic changes and increased vascular albumin permeation and urinary albumin excretion are aldose reductase-linked phenomena. Discordant effects of aldose reductase inhibitors on blood flow and vascular albumin permeation in some tissues suggest that increased vascular albumin permeation is not entirely attributable to hemodynamic change

  9. Measurement of hemodynamics during postural changes using a new wearable cephalic laser blood flowmeter.

    Science.gov (United States)

    Fujikawa, Tetsuya; Tochikubo, Osamu; Kura, Naoki; Kiyokura, Takanori; Shimada, Junichi; Umemura, Satoshi

    2009-10-01

    Patients with orthostatic hypotension have pathologic hemodynamics related to changes in body posture. A new cephalic laser blood flowmeter that can be worn on the tragus to investigate the hemodynamics upon rising from a sitting or squatting posture was developed. The relationship between cephalic hemodynamics and cerebral ischemic symptoms in 63 subjects in a sitting, squatting, and standing positions using the new device was evaluated. Transient decrease in blood pressure within 15 s after rising to an erect position possibly causes dizziness, syncope, and fall. Subjects exhibiting dizziness upon standing showed a significant decrease in the cephalic blood flow (CBF) and indirect beat-to-beat systolic blood pressure, as monitored by the Finometer, and a significant correlation was observed between the drop ratio (drop value on rising/mean value in the squatting position) of CBF and that of systolic blood pressure. This new wearable CBF-meter is potentially useful for estimating cephalic hemodynamics and objectively diagnosing cerebral ischemic symptoms of subjects in a standing posture.

  10. Modeling the hemodynamic response in fMRI using smooth FIR filters

    DEFF Research Database (Denmark)

    Goutte, Cyril; Nielsen, Finn Årup; Hansen, Lars Kai

    2000-01-01

    Modeling the hemodynamic response in functional magnetic resonance (fMRI) experiments is an important aspect of the analysis of functional neuroimages. This has been done in the past using parametric response function, from a limited family. In this contribution, the authors adopt a semi...

  11. Repeatability of fractional flow reserve despite variations in systemic and coronary hemodynamics

    NARCIS (Netherlands)

    Johnson, N.P.; Johnson, D.T.; Kirkeeide, R.L.; Berry, C.; de Bruyne, B.; Fearon, W.F.; Oldroyd, K.G.; Pijls, N.H.J.; Gould, K. Lance

    2015-01-01

    Objectives This study classified and quantified the variation in fractional flow reserve (FFR) due to fluctuations in systemic and coronary hemodynamics during intravenous adenosine infusion. Background Although FFR has become a key invasive tool to guide treatment, questions remain regarding its

  12. The effect of some hemodynamic factors on the behaviour of the aortic valve

    NARCIS (Netherlands)

    Steenhoven, van A.A.; Veenstra, P.C.; Reneman, R.S.

    1982-01-01

    To test the validity of a theoretical model of aortic valve closure, based upon the observations in a two-dimensional analogue, the effect of some hemodynamic factors on aortic valve behaviour was studied in open-chest dogs. Direct cinematography was used to record aortic valve movements. The ECG,

  13. The role of hemodynamics in the development of the outflow tract of the heart

    NARCIS (Netherlands)

    Loots, Erwin; Hillen, Berend; Veldman, Arthur E.P.

    The question whether, and if so to what extent, hemodynamic forces and mechanical stimuli do modulate the morphogenesis of the vascular system is a century-old problem. It is important especially in the outflow tract where a spiraling septum develops in and after a strong bend in the tube. Spiraling

  14. Cognitive function in patients with stable coronary heart disease: Related cerebrovascular and cardiovascular responses.

    Directory of Open Access Journals (Sweden)

    Mathieu Gayda

    Full Text Available Chronic exercise has been shown to prevent or slow age-related decline in cognitive functions in otherwise healthy, asymptomatic individuals. We sought to assess cognitive function in a stable coronary heart disease (CHD sample and its relationship to cerebral oxygenation-perfusion, cardiac hemodynamic responses, and [Formula: see text] peak compared to age-matched and young healthy control subjects. Twenty-two young healthy controls (YHC, 20 age-matched old healthy controls (OHC and 25 patients with stable CHD were recruited. Cognitive function assessment included short term-working memory, perceptual abilities, processing speed, cognitive inhibition and flexibility and long-term verbal memory. Maximal cardiopulmonary function (gas exchange analysis, cardiac hemodynamic (impedance cardiography and left frontal cerebral oxygenation-perfusion (near-infra red spectroscopy were measured during and after a maximal incremental ergocycle test. Compared to OHC and CHD, YHC had higher [Formula: see text] peak, maximal cardiac index (CI max, cerebral oxygenation-perfusion (ΔO2 Hb, ΔtHb: exercise and recovery and cognitive function (for all items (P<0.05. Compared to OHC, CHD patients had lower [Formula: see text] peak, CI max, cerebral oxygenation-perfusion (during recovery and short term-working memory, processing speed, cognitive inhibition and flexibility and long-term verbal memory (P<0.05. [Formula: see text] peak and CI max were related to exercise cerebral oxygenation-perfusion and cognitive function (P<0.005. Cerebral oxygenation-perfusion (exercise was related to cognitive function (P<0.005. Stable CHD patients have a worse cognitive function, a similar cerebral oxygenation/perfusion during exercise but reduced one during recovery vs. their aged-matched healthy counterparts. In the all sample, cognitive functions correlated with [Formula: see text] peak, CI max and cerebral oxygenation-perfusion.

  15. Hemodynamics, functional state of endothelium and renal function, platelets depending on the body mass index in patients with chronic heart failure and preserved systolic function

    Directory of Open Access Journals (Sweden)

    Kushnir Yu.

    2014-03-01

    Full Text Available The aim of the study was to evaluate hemodynamics, endothelium function of kidneys and platelets depending on the body mass index (BMI in patients with chronic heart failure (CHF and preserved systolic function. 42 patients (mean age - 76,690,83 years with CHF II-III FC NYHA with preserved systolic function (LVEF>45% were enrolled. Echocardiography was performed, endothelial function, serum creatinine levels and microalbuminuria were determined in patients. BMI and glomerulation filtration rate were calculated by formulas. The morphological and functional status of platelets was estimated by electronic microscopy. It was defined that increased BMI in patients with CHF and preserved systolic function determines the structural and functional changes of the myocardium and leads to the endothelial and renal functional changes. An increased risk of thrombogenesis was established in patients with overweight and obesity.

  16. Effect of etomidate and propofol induction on hemodynamic and endocrine response in patients undergoing coronary artery bypass grafting/mitral valve and aortic valve replacement surgery on cardiopulmonary bypass

    Directory of Open Access Journals (Sweden)

    Ram Prasad Kaushal

    2015-01-01

    Full Text Available Introduction: The concerns for induction of anaesthesia in patients undergoing cardiac surgery include hemodynamic stability, attenuation of stress response and maintenance of balance between myocardial oxygen demand and supply. Various Intravenous anaesthetic agents like Thiopentone, Etomidate, Propofol, Midazolam, and Ketamine have been used for anesthetizing patients for cardiac surgeries. However, many authors have expressed concerns regarding induction with thiopentone, midazolam and ketamine. Hence, Propofol and Etomidate are preferred for induction in these patients. However, these two drugs have different characteristics. Etomidate is preferred for patients with poor left ventricular (LV function as it provides stable cardiovascular profile. But there are concerns about reduction in adrenal suppression and serum cortisol levels. Propofol, on the other hand may cause a reduction in systemic vascular resistance and subsequent hypotension. Thus, this study was conducted to compare induction with these two agents in cardiac surgeries. Methods: Baseline categorical and continuous variables were compared using Fisher′s exact test and student′s t test respectively. Hemodynamic variables were compared using student′s t test for independent samples. The primary outcome (serum cortisol and blood sugar of the study was compared using Wilcoxon Rank Sum test. The P value less than 0.05 was considered significant. Results: Etomidate provides more stable hemodynamic parameters as compared to Propofol. Propofol causes vasodilation and may result in drop of systematic BP. Etomidate can therefore be safely used for induction in patients with good LV function for CABG/MVR/AVR on CPB without serious cortisol suppression lasting more than twenty-four hours.

  17. Disorders of cardiac hemodynamic in attack period of bronchial asthma in children

    Directory of Open Access Journals (Sweden)

    Kondratiev V.А.

    2016-05-01

    Full Text Available By dopplerechocardiography method there was studied functional state of cardiac ventricles and character of hemodynamic disorders in 48 patients aged 5-17 years in attack period of moderately-severe and severe bronchial asthma. Group of comparison included 40 healthy peers. Disorders of central and peripheral hemodynamic in attack period of bronchial asthma in children were accompanied both by systolic and diastolic dysfunction of the left and right heart ventricles, herewith right ventricle was functioning in the mode of hyperdynamic, and left one – in the mode of hypodynamic. Combined systolic-diastolic variant of dysfunction both of right and left ventricles was developing in 58,3% of patients with moderately-severe and in 91,6% of patients with severe bronchial asthma. In the attack period of bronchial asthma in children equal directionality of systolic and diastolic dysfunction of heart ventricles was developing; this was characterized by synchronization of their function. Assessment of functional interaction of the ventricles under conditions of severe asthma attack showed direct and high (r=0,67 correlative interaction between finding of Tei index of the left and right ventricles, which characterize their systolic function; this, under conditions of increased hemodynamic pre-loading testified to compensatory increase of systolic interaction of ventricles. Direct and high (r=0,69 correlative interaction between time indices of isovolumic relaxation of the left and right ventricles, characterizing their diastolic function, testified to compensatory increase of diastolic interaction of ventricles under conditions of increase of hemodynamic post-loading. Imbalance of central and peripheral link of hemodynamic in attack period of bronchial asthma in children testified to development of cardiac insufficiency, which was compensated predominantly at the expense of increase of heart contractions rate.

  18. Freedom Solo Versus Trifecta Bioprotheses: Clinical and Hemodynamic Evaluation after Propensity Score Matching.

    Science.gov (United States)

    J Cerqueira, Rui; Melo, Renata; Moreira, Soraia; A Saraiva, Francisca; Andrade, Marta; Salgueiro, Elson; Almeida, Jorge; J Amorim, Mário; Pinho, Paulo; Lourenço, André; F Leite-Moreira, Adelino

    2017-01-01

    To compare stentless Freedom Solo and stented Trifecta aortic bioprostheses regarding hemodynamic profile, left ventricular mass regression, early and late postoperative outcomes and survival. Longitudinal cohort study of consecutive patients undergoing aortic valve replacement (from 2009 to 2016) with either Freedom Solo or Trifecta at one centre. Local databases and national records were queried. Postoperative echocardiography (3-6 months) was obtained for hemodynamic profile (mean transprosthetic gradient and effective orifice area) and left ventricle mass determination. After propensity score matching (21 covariates), Kaplan-Meier analysis and cumulative incidence analysis were performed for survival and combined outcome of structural valve deterioration and endocarditis, respectively. Hemodynamics and left ventricle mass regression were assessed by a mixed- -effects model including propensity score as a covariate. From a total sample of 397 Freedom Solo and 525 Trifecta patients with a median follow-up time of 4.0 (2.2- 6.0) and 2.4 (1.4-3.7) years, respectively, a matched sample of 329 pairs was obtained. Well-balanced matched groups showed no difference in survival (hazard ratio=1.04, 95% confidence interval=0.69-1.56) or cumulative hazards of combined outcome (subhazard ratio=0.54, 95% confidence interval=0.21-1.39). Although Trifecta showed improved hemodynamic profile compared to Freedom Solo, no differences were found in left ventricle mass regression. Trifecta has a slightly improved hemodynamic profile compared to Freedom Solo but this does not translate into differences in the extent of mass regression, postoperative outcomes or survival, which were good and comparable for both bioprostheses. Long-term follow-up is needed for comparisons with older models of bioprostheses.

  19. [Meta-analyses on measurement precision of non-invasive hemodynamic monitoring technologies in adults].

    Science.gov (United States)

    Pestel, G; Fukui, K; Higashi, M; Schmidtmann, I; Werner, C

    2018-06-01

    An ideal non-invasive monitoring system should provide accurate and reproducible measurements of clinically relevant variables that enables clinicians to guide therapy accordingly. The monitor should be rapid, easy to use, readily available at the bedside, operator-independent, cost-effective and should have a minimal risk and side effect profile for patients. An example is the introduction of pulse oximetry, which has become established for non-invasive monitoring of oxygenation worldwide. A corresponding non-invasive monitoring of hemodynamics and perfusion could optimize the anesthesiological treatment to the needs in individual cases. In recent years several non-invasive technologies to monitor hemodynamics in the perioperative setting have been introduced: suprasternal Doppler ultrasound, modified windkessel function, pulse wave transit time, radial artery tonometry, thoracic bioimpedance, endotracheal bioimpedance, bioreactance, and partial CO 2 rebreathing have been tested for monitoring cardiac output or stroke volume. The photoelectric finger blood volume clamp technique and respiratory variation of the plethysmography curve have been assessed for monitoring fluid responsiveness. In this manuscript meta-analyses of non-invasive monitoring technologies were performed when non-invasive monitoring technology and reference technology were comparable. The primary evaluation criterion for all studies screened was a Bland-Altman analysis. Experimental and pediatric studies were excluded, as were all studies without a non-invasive monitoring technique or studies without evaluation of cardiac output/stroke volume or fluid responsiveness. Most studies found an acceptable bias with wide limits of agreement. Thus, most non-invasive hemodynamic monitoring technologies cannot be considered to be equivalent to the respective reference method. Studies testing the impact of non-invasive hemodynamic monitoring technologies as a trend evaluation on outcome, as well as

  20. Correction of Hemodynamic Disorders in the Complex Surgical Correction of Acquired Cardiac Valvular Defects

    Directory of Open Access Journals (Sweden)

    A. I. Lenkin

    2011-01-01

    Full Text Available Objective: to compare the efficiency of using the values of transpulmonary (PiCCO and prepulmonary (Swan-Ganz catheter thermodilution as guides to targeted therapy for hemodynamic disorders in the surgical correction of mixed cardiac valvular defects. Subjects and methods. The study enrolled 40 patients operated on for acquired cardiac diseases who were randomized to two matched groups. Hemodynamics was monitored by means of a Swan-Ganz catheter in Group 1 and by transpulmonary thermodilution in Group 2. Anesthesia was maintained with propofol and fentanyl. Infusion therapy was performed using crystalloid and colloid solutions. Continuous intravenous infusion of inotropic agents was used when heart failure was developed. Hemodynamic, clinical, and laboratory parameters were estimated intraoperatively and within 24 hours postoperatively. Results. The groups did not differ in the degree of baseline heart failure, the duration of an operation and myocardial ischemia, and the length of extracorporeal circulation. In the PiCCO group, postoperative infusion volume was 33% higher than that in the Swan-Ganz group, which ensured increases in stroke volume and oxygen delivery in the early postoperative period (p<0.05. Respiratory support was 26% shorter in the PiCCO group (p<0.04. Conclusion. After surgical interventions for mixed cardiac defects, the targeted therapy algorithm based on transpulmonary thermodilution provided more steady-state values of hemodynamics and oxygen transport, which was followed by the increased scope of infusion therapy and the shorter length of postoperative mechanical ventilation than that based on hemodynamics being corrected from the values of prepul-monary thermodilution. Key words: transpulmonary thermodilution, targeted therapy, prepulmonary ther-modilution, acquired heart disease.

  1. Association between percutaneous hemodynamic support device and survival from cardiac arrest in the state of Michigan.

    Science.gov (United States)

    Pressman, Andrew; Sawyer, Kelly N; Devlin, William; Swor, Robert

    2018-05-01

    The role of circulatory support in the post-cardiac arrest period remains controversial. Our objective was to investigate the association between treatment with a percutaneous hemodynamic support device and outcome after admission for cardiac arrest. We performed a retrospective study of adult patients with admission diagnosis of cardiac arrest or ventricular fibrillation (VF) from the Michigan Inpatient Database, treated between July 1, 2010, and June 30, 2013. Patient demographics, clinical characteristics, treatments, and disposition were electronically abstracted based on ICD-9 codes at the hospital level. Mixed-effects logistic regression models were fit to test the effect of percutaneous hemodynamic support device defined as either percutaneous left ventricular assist device (pLVAD) or intra-aortic balloon pump (IABP) on survival. These models controlled for age, sex, VF, myocardial infarction (MI), and cardiogenic shock with hospital modeled as a random effect. A total of 103 hospitals contributed 4393 patients for analysis, predominately male (58.8%) with a mean age of 64.1years (SD 15.5). On univariate analysis, younger age, male sex, VF as the initial rhythm, acute MI, percutaneous coronary intervention, percutaneous hemodynamic support device, and absence of cardiogenic shock were associated with survival to discharge (each p<0.001). Mixed-effects logistic regressions revealed use of percutaneous hemodynamic support device was significantly associated with survival among all patients (OR 1.8 (1.28-2.54)), and especially in those with acute MI (OR 1.95 (1.31-2.93)) or cardiogenic shock (OR 1.96 (1.29-2.98)). Treatment with percutaneous hemodynamic support device in the post-arrest period may provide left ventricular support and improve outcome. Copyright © 2017 Elsevier Inc. All rights reserved.

  2. Association between hemodynamic modifications and clinical outcome of intracranial aneurysms treated using flow diverters.

    Science.gov (United States)

    Paliwal, Nikhil; Damiano, Robert J; Davies, Jason M; Siddiqui, Adnan H; Meng, Hui

    2017-02-11

    Treatment of intracranial aneurysms (IAs) has been revolutionized by the advent of endovascular Flow Diverters (FDs), which disrupt blood flow within the aneurysm to induce pro-thrombotic conditions, and serves as a scaffold for endothelial ingrowth and arterial remodeling. Despite good clinical success of FDs, complications like incomplete occlusion and post-treatment rupture leading to subarachnoid hemorrhage have been reported. In silico computational fluid dynamic analysis of the pre- and post-treated geometries of IA patients can shed light on the contrasting blood hemodynamics associated with different clinical outcomes. In this study, we analyzed hemodynamic modifications in 15 IA patients treated using a single FD; 10 IAs were completely occluded (successful) and 5 were partially occluded (unsuccessful) at 12-month follow-up. An in-house virtual stenting workflow was used to recapitulate the clinical intervention on these cases, followed by CFD to obtain pre- and post-treatment hemodynamics. Bulk hemodynamic parameters showed comparable reductions in both groups with average inflow rate and aneurysmal velocity reduction of 40.3% and 52.4% in successful cases, and 34.4% and 49.2% in unsuccessful cases. There was a substantial reduction in localized parameter like vortex coreline length and Energy Loss for successful cases, 38.2% and 42.9% compared to 10.1% and 10.5% for unsuccessful cases. This suggest that for successfully treated IAs, the localized complex blood flow is disrupted more prominently by the FD as compared to unsuccessful cases. These localized hemodynamic parameters can be potentially used in prediction of treatment outcome, thus aiding the clinicians in a priori assessment of different treatment strategies.

  3. Myocardial hypertrophy and intracardial hemodynamics in children with bicuspid aortic valve

    Directory of Open Access Journals (Sweden)

    А. V. Kamenshchyk

    2017-08-01

    Full Text Available Bicuspid aortic valve is one of the most common congenital heart diseases with low manifestation in childhood and severe consequences in adults that determines the importance in early diagnostics of myocardial changes in this anomaly. According to the literature the polymorphisms in the genes of NFATC family could result both in impaired embriogenetic valves formation and development of postnatal myocardial hypertrophy. The aim of the study was to detect the early changes of intracardial hemodynamics at aortic valve in children with bicuspid aortic valve (BAV and establish their interrelations to the signs of myocardial hypertrophy in these children. Materials and methods: Dopplerograhphic study of basic intracardiac hemodynamics parameters in 38 children with BAV and in 28 children of control group was conducted. The results were processed statistically by Student’s t-test, correlation analysis and multiple regression. Results: In the result of study the moderate concentric left ventricle myocardial hypertrophy development was detected in 62 % of children with BAV which is accompanying to significant increasing of blood flow velocity and pressure gradient at aortic valve. There were not established significant correlations between the parameters of hemodynamics at valve and left ventricle’s posterior wall depth and septum depth whereas the highest inputs of these values were obtained in the left ventricle systolic dimension and volume and less in the hypertrophic signs. Conclusions: In children with BAV the moderate concentric myocardial hypertrophy with significant changes of intracardial hemodynamics at aortic valve takes place with the highest inputs in left ventricle volumetric values The obtained data serves as a substantiation for the treatment and prevention of it further development. bicuspid aortic valve; children; heart hypertrophy; dopplerechocardiography; hemodynamics; regression analysis

  4. Stock Status

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — These data inform the public of the most recent stock status for all stocks (FSSI and non-FSSI) in the fishery management unit contained in a fishery managment plan....

  5. Combined use of 64-slice computed tomography angiography and gated myocardial perfusion SPECT for the detection of functionally relevant coronary artery stenoses. First results in a clinical setting concerning patients with stable angina

    International Nuclear Information System (INIS)

    Hacker, M.; Hack, N.; Tiling, R.; Jakobs, T.; Nikolaou, K.; Becker, C.; Ziegler, F. von; Knez, A.; Koenig, A.; Klauss, V.

    2007-01-01

    Aim: In patients with stable angina pectoris both morphological and functional information about the coronary artery tree should be present before revascularization therapy is performed. High accuracy was shown for spiral computed tomography (MDCT) angiography acquired with a 64-slice CT scanner compared to invasive coronary angiography (ICA) in detecting obstructive'' coronary artery disease (CAD). Gated myocardial SPECT (MPI) is an established method for the noninvasive assessment of functional significance of coronary stenoses. Aim of the study was to evaluate the combination of 64-slice CT angiography plus MPI in comparison to ICA plus MPI in the detection of hemodynamically relevant coronary artery stenoses in a clinical setting. Patients, methods: 30 patients (63 ± 10.8 years, 23 men) with stable angina (21 with suspected, 9 with known CAD) were investigated. MPI, 64-slice CT angiography and ICA were performed, reversible and fixed perfusion defects were allocated to determining lesions separately for MDCT angiography and ICA. The combination of MDCT angiography plus MPI was compared to the results of ICA plus MPI. Results: Sensitivity, specificity, negative and positive predictive value for the combination of MDCT angiography plus MPI was 85%, 97%, 98% and 79%, respectively, on a vessel-based and 93%, 87%, 93% and 88%, respectively, on a patient-based level. 19 coronary arteries with stenoses =50% in both ICA and MDCT angiography showed no ischemia in MPI. Conclusion: The combination of 64-slice CT angiography and gated myocardial SPECT enabled a comprehensive non-invasive view of the anatomical and functional status of the coronary artery tree. (orig.)

  6. Combined use of 64-slice computed tomography angiography and gated myocardial perfusion SPECT for the detection of functionally relevant coronary artery stenoses. First results in a clinical setting concerning patients with stable angina

    Energy Technology Data Exchange (ETDEWEB)

    Hacker, M.; Hack, N.; Tiling, R. [Klinikum Grosshadern (Germany). Dept. of Nuclear Medicine; Jakobs, T.; Nikolaou, K.; Becker, C. [Klinikum Grosshadern (Germany). Dept. of Clinical Radiology; Ziegler, F. von; Knez, A. [Klinikum Grosshadern (Germany). Dept. of Cardiology; Koenig, A.; Klauss, V. [Medizinische Poliklinik-Innenstadt, Univ. of Munich (Germany). Dept. of Cardiology

    2007-07-01

    Aim: In patients with stable angina pectoris both morphological and functional information about the coronary artery tree should be present before revascularization therapy is performed. High accuracy was shown for spiral computed tomography (MDCT) angiography acquired with a 64-slice CT scanner compared to invasive coronary angiography (ICA) in detecting ''obstructive'' coronary artery disease (CAD). Gated myocardial SPECT (MPI) is an established method for the noninvasive assessment of functional significance of coronary stenoses. Aim of the study was to evaluate the combination of 64-slice CT angiography plus MPI in comparison to ICA plus MPI in the detection of hemodynamically relevant coronary artery stenoses in a clinical setting. Patients, methods: 30 patients (63 {+-} 10.8 years, 23 men) with stable angina (21 with suspected, 9 with known CAD) were investigated. MPI, 64-slice CT angiography and ICA were performed, reversible and fixed perfusion defects were allocated to determining lesions separately for MDCT angiography and ICA. The combination of MDCT angiography plus MPI was compared to the results of ICA plus MPI. Results: Sensitivity, specificity, negative and positive predictive value for the combination of MDCT angiography plus MPI was 85%, 97%, 98% and 79%, respectively, on a vessel-based and 93%, 87%, 93% and 88%, respectively, on a patient-based level. 19 coronary arteries with stenoses =50% in both ICA and MDCT angiography showed no ischemia in MPI. Conclusion: The combination of 64-slice CT angiography and gated myocardial SPECT enabled a comprehensive non-invasive view of the anatomical and functional status of the coronary artery tree. (orig.)

  7. Toward Practical Secure Stable Matching

    Directory of Open Access Journals (Sweden)

    Riazi M. Sadegh

    2017-01-01

    Full Text Available The Stable Matching (SM algorithm has been deployed in many real-world scenarios including the National Residency Matching Program (NRMP and financial applications such as matching of suppliers and consumers in capital markets. Since these applications typically involve highly sensitive information such as the underlying preference lists, their current implementations rely on trusted third parties. This paper introduces the first provably secure and scalable implementation of SM based on Yao’s garbled circuit protocol and Oblivious RAM (ORAM. Our scheme can securely compute a stable match for 8k pairs four orders of magnitude faster than the previously best known method. We achieve this by introducing a compact and efficient sub-linear size circuit. We even further decrease the computation cost by three orders of magnitude by proposing a novel technique to avoid unnecessary iterations in the SM algorithm. We evaluate our implementation for several problem sizes and plan to publish it as open-source.

  8. Stable isotope research pool inventory

    International Nuclear Information System (INIS)

    1986-08-01

    This report contains a listing of electromagnetically separated stable isotopes which are available at the Oak Ridge National Laboratory for distribution for nondestructive research use on a loan basis. This inventory includes all samples of stable isotopes in the Research Materials Collection and does not designate whether a sample is out on loan or is in reprocessing. For some of the high-abundance, naturally occurring isotopes, larger amounts can be made available; for example, Ca-40 and Fe-56. All requests for the loan of samples should be submitted with a summary of the purpose of the loan to: Iotope Distribution Office, Oak Ridge National Laboratory, P.O. Box X, Oak Ridge, Tennessee 37831. Requests from non-DOE contractors and from foreign institutions require DOE approval

  9. Stable isotopes and the environment

    International Nuclear Information System (INIS)

    Krouse, H.R.

    1990-01-01

    Whereas traditionally, stable isotope research has been directed towards resource exploration and development, it is finding more frequent applications in helping to assess the impacts of resource utilization upon ecosystems. Among the many pursuits, two themes are evident: tracing the transport and conversions of pollutants in the environment and better understanding of the interplay among environmental receptors, e.g. food web studies. Stable isotope data are used primarily to identify the presence of pollutants in the environment and with a few exceptions, the consequence of their presence must be assessed by other techniques. Increasing attention has been given to the isotopic composition of humans with many potential applications in areas such as paleodiets, medicine, and criminology. In this brief overview examples are used from the Pacific Rim to illustrate the above concepts. 26 refs., 1 tab., 3 figs

  10. Ionizing radiation occupational exposure in the hemodynamics services; Exposicao ocupacional as radiacoes ionizantes nos servicos de hemodinamica

    Energy Technology Data Exchange (ETDEWEB)

    Gronchi, Claudia Carla

    2004-07-01

    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{sub 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)

  11. Measurements of coherent hemodynamics to enrich the physiological information provided by near-infrared spectroscopy (NIRS) and functional MRI

    Science.gov (United States)

    Sassaroli, Angelo; Tgavalekos, Kristen; Pham, Thao; Krishnamurthy, Nishanth; Fantini, Sergio

    2018-02-01

    Hemodynamic-based neuroimaging techniques such as functional magnetic resonance imaging (fMRI) and near-infrared spectroscopy (NIRS) sense hemoglobin concentration in cerebral tissue. The local concentration of hemoglobin, which is differentiated into oxy- and deoxy-hemoglobin by NIRS, features spontaneous oscillations over time scales of 10-100 s in response to a number of local and systemic physiological processes. If one of such processes becomes the dominant source of cerebral hemodynamics, there is a high coherence between this process and the associated hemodynamics. In this work, we report a method to identify such conditions of coherent hemodynamics, which may be exploited to study and quantify microvasculature and microcirculation properties. We discuss how a critical value of significant coherence may depend on the specific data collection scheme (for example, the total acquisition time) and the nature of the hemodynamic data (in particular, oxy- and deoxy-hemoglobin concentrations measured with NIRS show an intrinsic level of correlation that must be taken into account). A frequency-resolved study of coherent hemodynamics is the basis for the new technique of coherent hemodynamics spectroscopy (CHS), which aims to provide measures of cerebral blood flow and cerebral autoregulation. While these concepts apply in principle to both fMRI and NIRS data, in this article we focus on NIRS data.

  12. Towards stable acceleration in LINACS

    CERN Document Server

    Dubrovskiy, A D

    2014-01-01

    Ultra-stable and -reproducible high-energy particle beams with short bunches are needed in novel linear accelerators and, in particular, in the Compact Linear Collider CLIC. A passive beam phase stabilization system based on a bunch compression with a negative transfer matrix element R56 and acceleration at a positive off-crest phase is proposed. The motivation and expected advantages of the proposed scheme are outlined.

  13. Stable Structures for Distributed Applications

    OpenAIRE

    Eugen DUMITRASCU; Ion IVAN

    2008-01-01

    For distributed applications, we define the linear, tree and graph structure types with different variants and modalities to aggregate them. The distributed applications have assigned structures that through their characteristics influence the costs of stages for developing cycle and the costs for exploitation, transferred to each user. We also present the quality characteristics of a structure for a stable application, which is focused on stability characteristic. For that characteristic we ...

  14. Permanent education that approaches radiation protection in hemodynamic service; Educacao permanente que aborde radioprotecao em servico de hemodinamica

    Energy Technology Data Exchange (ETDEWEB)

    Flor, Rita de Cassia; Anjos, Djeniffer Valdirene dos, E-mail: flor@ifsc.edu.b [Instituto Federal de Santa Catarina (IF-SC), Florianopolis, SC (Brazil)

    2011-10-26

    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 evaluation before and after the STA-MCA anastomosis

    International Nuclear Information System (INIS)

    Touho, Hajime; Karasawa, Jun; Shishido, Hisashi; Yamada, Keisuke; Shibamoto, Keiji

    1990-01-01

    Twenty-seven patients with minor completed and major stroke in the chronic stage underwent superficial temporal artery-middle cerebral artery (STA-MCA) anastomosis. The regional cerebral blood flow (rCBF), using inhalation of stable xenon and computed tomographic scanning (Xe s CT-CBF study), and the mode of transit time (MTT) in the MCA territory using intra-arterial digital aortography were measured. Activated rCBF and MTT was measured 20 minutes after the administration of acetazolamide (10 mg/kg) in 14 patients. Nineteen of the 23 patients with minor stroke (Group 1) showed immediate improvement in their neurological state within a few days of the operation, while four patients with minor stroke (Group 2) and four patients with major stroke (Group 3) showed no improvement. Based on the rCBF obtained with the Xe s CT-CBF study, affected side rCBF/unaffected side rCBF and %f [(peak DSA number/affected side MTT)/(peak DSA number/unaffected side MTT)] were compared. There was a significant positive correlation. Affected side MTT in Group 1 was 6.41±1.16 sec, preoperatively, and significantly decreased to 5.13±0.91 sec after the operation. On the other hand, preoperative MTT in Group 2 was 4.40±0.81 sec and 4.76±0.89 sec, postoperatively. Preoperative %f in Group 1 was 0.514±0.143 and significantly increased to 0.739±0.154, postoperatively. Group 2 showed no change. Vasodilatory capacity with acetazolamide showed a marked improvement in Group 1, postoperativery. Our study indicated that if MTT is moderately lengthened, %f is moderately decreased, and vasodilatory capacity is impaired, in patients with minor ischemic stroke will benefit from STA-MCA anastomosis. (author)

  16. Organic synthesis with stable isotopes

    International Nuclear Information System (INIS)

    Daub, G.H.; Kerr, V.N.; Williams, D.L.; Whaley, T.W.

    1978-01-01

    Some general considerations concerning organic synthesis with stable isotopes are presented. Illustrative examples are described and discussed. The examples include DL-2-amino-3-methyl- 13 C-butanoic-3,4- 13 C 2 acid (DL-valine- 13 C 3 ); methyl oleate-1- 13 C; thymine-2,6- 13 C 2 ; 2-aminoethanesulfonic- 13 C acid (taurine- 13 C); D-glucose-6- 13 C; DL-2-amino-3-methylpentanoic-3,4- 13 C 2 acid (DL-isoleucine- 13 C 2 ); benzidine- 15 N 2 ; and 4-ethylsulfonyl-1-naphthalene-sulfonamide- 15 N

  17. Stable isotopes - separation and application

    International Nuclear Information System (INIS)

    Lockhart, I.M.

    1980-01-01

    In this review, methods used for the separation of stable isotopes ( 12 C, 13 C, 14 N, 15 N, 16 O, 17 O, 18 O, 34 S) will be described. The synthesis of labelled compounds, techniques for detection and assay, and areas of application will also be discussed. Particular attention will be paid to the isotopes of carbon, nitrogen, and oxygen; to date, sulphur isotopes have only assumed a minor role. The field of deuterium chemistry is too extensive for adequate treatment; it will therefore be essentially excluded. (author)

  18. Stable agents for imaging investigations

    International Nuclear Information System (INIS)

    Tofe, A.J.

    1976-01-01

    This invention concerns highly stable compounds useful in preparing technetium 99m based scintiscanning exploration agents. The compounds of this invention include a pertechnetate reducing agent or a solution of oxidized pertechnetate and an efficient proportion, sufficient to stabilize the compounds in the presence of oxygen and of radiolysis products, of ascorbic acid or a pharmaceutically acceptable salt or ester of this acid. The invention also concerns a perfected process for preparing a technetium based exploration agent, consisting in codissolving the ascorbic acid or a pharmaceutically acceptable salt or ester of such an acid and a pertechnetate reducing agent in a solution of oxidized pertechnetate [fr

  19. Intravenous dexmedetomidine infusion in adult patients undergoing open nephrolithotomy: Effects on intraoperative hemodynamics and blood loss; a random

    Directory of Open Access Journals (Sweden)

    Doaa A. Rashwan

    2015-10-01

    Conclusion: Dexmedetomidine infusion in patients undergoing open nephrolithotomy under general anesthesia was associated with intraoperative hemodynamic stability, which decreases intraoperative blood loss and the need for intraoperative blood transfusion.

  20. Stable cosmology in chameleon bigravity

    Science.gov (United States)

    De Felice, Antonio; Mukohyama, Shinji; Oliosi, Michele; Watanabe, Yota

    2018-02-01

    The recently proposed chameleonic extension of bigravity theory, by including a scalar field dependence in the graviton potential, avoids several fine-tunings found to be necessary in usual massive bigravity. In particular it ensures that the Higuchi bound is satisfied at all scales, that no Vainshtein mechanism is needed to satisfy Solar System experiments, and that the strong coupling scale is always above the scale of cosmological interest all the way up to the early Universe. This paper extends the previous work by presenting a stable example of cosmology in the chameleon bigravity model. We find a set of initial conditions and parameters such that the derived stability conditions on general flat Friedmann background are satisfied at all times. The evolution goes through radiation-dominated, matter-dominated, and de Sitter eras. We argue that the parameter space allowing for such a stable evolution may be large enough to encompass an observationally viable evolution. We also argue that our model satisfies all known constraints due to gravitational wave observations so far and thus can be considered as a unique testing ground of gravitational wave phenomenologies in bimetric theories of gravity.

  1. Stable Heavy Hadrons in ATLAS

    CERN Document Server

    Mackeprang, Rasmus

    2007-01-01

    Several extensions to the SM feature heavy long-lived particles with masses of O(10^2-10^3 GeV) and mean lifetimes fulfilling $CT \\geq 10m$. Among such theories are supersymmetric scenarios as well as extra-dimensional models in which the heavy new particles are seen as Kaluza-Klein excitations of the well-known SM particles. Such particles will, from the point of view of a collider experiment be seen as stable. This thesis is concerned with the case where the exotic heavy particles emph{can} be considered stable while traversing the detector. Specifically the case is considered where the particles in question carry the charge of the strong nuclear force, commonly referred to as emph{colour charge}. A simulation kit has been developed using GEANT4. This framework is the current standard in experimental particle physics for the simulation of interactions of particles with matter, and it is used extensively for detector simulation. The simulation describes the interactions of these particles with matter which i...

  2. Compliance status

    International Nuclear Information System (INIS)

    Black, D.G.

    1995-01-01

    This section of the 1994 Hanford Site Environmental Report summarizes the activities conducted to ensure that the Hanford Site is in compliance with federal environmental protection statutes and related Washington State and local environmental protection regulations and the status of Hanford's compliance with these requirements. Environmental permits required under the environmental protection regulations are discussed under the applicable statute

  3. Compliance status

    Energy Technology Data Exchange (ETDEWEB)

    Black, D.G.

    1995-06-01

    This section of the 1994 Hanford Site Environmental Report summarizes the activities conducted to ensure that the Hanford Site is in compliance with federal environmental protection statutes and related Washington State and local environmental protection regulations and the status of Hanford`s compliance with these requirements. Environmental permits required under the environmental protection regulations are discussed under the applicable statute.

  4. STATUS REPORT

    Indian Academy of Sciences (India)

    First page Back Continue Last page Graphics. STATUS REPORT. Raman scattering observed – 90, 135, 180 degrees and back scattering. Traditionally specific angle dependence to learn about polarization response. Learn molecular information from the surface or materials just below the surface (upto 12 mm depth) ...

  5. 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.

  6. Improving Perioperative Outcomes Through Minimally Invasive and Non-invasive Hemodynamic Monitoring Techniques

    Directory of Open Access Journals (Sweden)

    Takashige Yamada

    2018-05-01

    Full Text Available An increasing number of patients require precise intraoperative hemodynamic monitoring due to aging and comorbidities. To prevent undesirable outcomes from intraoperative hypotension or hypoperfusion, appropriate threshold settings are required. These setting can vary widely from patient to patient. Goal-directed therapy techniques allow for flow monitoring as the standard for perioperative fluid management. Based on the concept of personalized medicine, individual assessment and treatment are more advantageous than conventional or uniform interventions. The recent development of minimally and noninvasive monitoring devices make it possible to apply detailed control, tracking, and observation of broad patient populations, all while reducing adverse complications. In this manuscript, we review the monitoring features of each device, together with possible advantages and disadvantages of their use in optimizing patient hemodynamic management.

  7. Computational modeling of local hemodynamics phenomena: methods, tools and clinical applications

    International Nuclear Information System (INIS)

    Ponzini, R.; Rizzo, G.; Vergara, C.; Veneziani, A.; Morbiducci, U.; Montevecchi, F.M.; Redaelli, A.

    2009-01-01

    Local hemodynamics plays a key role in the onset of vessel wall pathophysiology, with peculiar blood flow structures (i.e. spatial velocity profiles, vortices, re-circulating zones, helical patterns and so on) characterizing the behavior of specific vascular districts. Thanks to the evolving technologies on computer sciences, mathematical modeling and hardware performances, the study of local hemodynamics can today afford also the use of a virtual environment to perform hypothesis testing, product development, protocol design and methods validation that just a couple of decades ago would have not been thinkable. Computational fluid dynamics (Cfd) appears to be more than a complementary partner to in vitro modeling and a possible substitute to animal models, furnishing a privileged environment for cheap fast and reproducible data generation.

  8. Hemodynamic responses to seated and supine lower body negative pressure - Comparison with +Gz acceleration

    Science.gov (United States)

    Polese, Alvese; Sandler, Harold; Montgomery, Leslie D.

    1992-01-01

    The hemodynamic responses to LBNP in seated subjects and in subjects in supine body positions were compared and were correlated with hemodynamic changes which occurred during a simulated (by centrifugation) Shuttle reentry acceleration with a slow onset rate of 0.002 G/s and during gradual onset exposures to +3 Gz and +4 Gz. Results demonstrate that seated LBNP at a level of -40 mm Hg can serve as a static simulator for changes in the heart rate and in mean blood pressure induced by gradual onset acceleration stress occurring during Shuttle reentry. The findings also provide a rationale for using LBNP during weightlessness as a means of imposing G-loading on the circulation prior to reentry.

  9. Basilar artery angulation and vertigo due to the hemodynamic effect of dominant vertebral artery.

    Science.gov (United States)

    Cosar, Murat; Yaman, Mehmet; Eser, Olcay; Songur, Ahmet; Ozen, Oguz A

    2008-01-01

    Vertebral arteries form the basilar artery at the pontobulbar junction. The vertebral artery may have dominancy in one of them. The branches of basilar arteries supply blood for the vestibular nuclei and its connections. Vertigo is seen generally in the upper middle aged patients. Vertigo can be observed in dolichoectasia of basilar artery such as angulation and elongation, because of the diminished blood supply and changed hemodynamic factors of vestibular nuclei and its connections. We hypothesized that angulation or elongation of basilar artery can be estimated according to the unilateral vertebral artery dominant hypertensive patients. The basilar artery can angulate from the dominant side of vertebral artery to the recessive side. These angulation and elongation can effect the hemodynamic factors in absence of growing collateral arteries. So, the vertigo attacks may occur in these patients.

  10. 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 supine patient, we studied the humoral and central hemodynamic responses to changes with posture. Twenty-three patients with alcoholic cirrhosis (Child-Turcotte-Pugh classes A/B/C: 2/13/8) and 14 healthy controls were entered. Measurements of central hemodynamics and activation of SNS and RAAS were taken......). Central circulation time increased only in the patients (+30% vs. -1%, P higher in the patients than in the controls (P

  11. The Effects of Hemodynamic Changes on Pulse Wave Velocity in Cardiothoracic Surgical Patients

    Directory of Open Access Journals (Sweden)

    Yurie Obata

    2016-01-01

    Full Text Available The effect of blood pressure on pulse wave velocity (PWV is well established. However, PWV variability with acute hemodynamic changes has not been examined in the clinical setting. The aim of the present study is to investigate the effect of hemodynamic changes on PWV in patients who undergo cardiothoracic surgery. Using data from 25 patients, we determined blood pressure (BP, heart rate (HR, and the left ventricular outflow tract (LVOT velocity-time integral. By superimposing the radial arterial waveform on the continuous wave Doppler waveform of the LVOT, obtained by transesophageal echo, we were able to determine pulse transit time and to calculate PWV, stroke volume (SV, cardiac output (CO, and systemic vascular resistance (SVR. Increases in BP, HR, and SVR were associated with higher values for PWV. In contrast increases in SV were associated with decreases in PWV. Changes in CO were not significantly associated with PWV.

  12. Hemodynamics and Gas Exchange Effects of Inhaled Nitrous Oxide in Patients with Acute Respiratory Distress Syndrome

    Directory of Open Access Journals (Sweden)

    V. N. Poptsov

    2006-01-01

    Full Text Available Inhaled nitrous oxide (iNO therapy aimed at improving pulmonary oxygenizing function and at decreasing artificial ventilation (AV load has been used in foreign clinical practice in the past decade. The study was undertaken to evaluate the hemodynamic and gas exchange effects of iNO in acute respiratory distress syndrome (ARDS that developed after car-diosurgical operations. Fifty-eight (43 males and 15 females patients aged 21 to 76 (55.2±2.4 years were examined. The study has demonstrated that in 48.3% of cases, the early stage of ARDS is attended by the increased tone pulmonary vessels due to impaired NO-dependent vasodilatation. In these patients, iNO therapy is an effective therapeutic method for correcting hemodynamic disorders and lung oxygenizing function.

  13. 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

    , and arterial pressure were determined before and during a volume expansion induced by infusion of a hyperosmotic galactose solution. RESULTS: During volume expansion, the central and arterial blood volume increased significantly in patients with class A and controls, whereas no significant change was found...... 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......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...

  14. Hemodynamic and glucometabolic factors in the prediction of left ventricular filling pressures

    DEFF Research Database (Denmark)

    Pareek, M; Nielsen, M L; Olesen, T B

    2015-01-01

    OBJECTIVE: To explore possible hemodynamic and glucometabolic determinants of left ventricular filling pressures as assessed by the non-invasive surrogate marker, averaged E/é, in otherwise healthy, middle-aged male survivors from a random population sample. DESIGN AND METHODS: Prospective.......01). We did not find any significant interactions in the prediction of E/é. CONCLUSION: In a prospective population-based cohort study including apparently healthy, middle-aged male subjects, higher age, BMI, and creatinine, but not SBP or HR, were significantly associated with higher left ventricular...... population-based cohort study examining associations between hemodynamic factors [systolic blood pressure (SBP), heart rate (HR)), glucometabolic factors (fasting blood glucose, fasting plasma insulin, Homeostatic Model Assessment (HOMA) derived indices of beta-cell function (HOMA-2B) and insulin sensitivity...

  15. Estimating changes in cardiac output using an implanted hemodynamic monitor in heart failure patients

    DEFF Research Database (Denmark)

    Ståhlberg, Marcus; Damgaard, Morten; Ersgård, David

    2010-01-01

    OBJECTIVES: The aim of this study was to evaluate an algorithm that estimates changes in cardiac output (CO) from right ventricular (RV) pressure waveforms derived from an implantable hemodynamic monitor (IHM) in heart failure patients. DESIGN: Twelve heart failure patients (NYHA II-III, EF 32......%) with an implantable hemodynamic monitor (Chronicle) were included in this study. Changes in cardiac output were provoked by body position change at rest (left lateral supine, horizontal supine, sitting, and standing) and a steady state bicycle exercise at 20 watts. Estimated CO derived from the IHM (CO...... was -0.39 L/min (11%). Limits of agreement were +/-1.56 L/min and relative error was 21%. CONCLUSIONS: A simple algorithm based on RV pressure wave form characteristics derived from an IHM can be used to estimate changes in CO in heart failure patients. These findings encourage further research aiming...

  16. Sex differences in the hemodynamic responses to mental stress: Effect of caffeine consumption.

    Science.gov (United States)

    Farag, Noha H; Vincent, Andrea S; McKey, Barbara S; Al'Absi, Mustafa; Whitsett, Thomas L; Lovallo, William R

    2006-07-01

    The effect of caffeine on stress responses was compared in 25 men and 22 women in a 2-week placebo-controlled, double-blind, randomized crossover trial. On each week, participants abstained from all dietary sources of caffeine before undergoing a 6-h laboratory protocol under placebo or caffeine exposure followed by a 30-min mental stressor with blood pressure (BP) and cardiovascular hemodynamic assessments. On the placebo session, men and women showed a significant BP increase to stress, although women had significant cardiac responses whereas men had vascular responses. Caffeine ingestion before stress caused both men and women to have enhanced hemodynamic responses to the stressor associated with an increase in cardiac index and a drop in the peripheral resistance index. Caffeine enhances the cardiovascular fight-or-flight response pattern to stress in men and women.

  17. Simulation of microcirculatory hemodynamics: estimation of boundary condition using particle swarm optimization.

    Science.gov (United States)

    Pan, Qing; Wang, Ruofan; Reglin, Bettina; Fang, Luping; Pries, Axel R; Ning, Gangmin

    2014-01-01

    Estimation of the boundary condition is a critical problem in simulating hemodynamics in microvascular networks. This paper proposed a boundary estimation strategy based on a particle swarm optimization (PSO) algorithm, which aims to minimize the number of vessels with inverted flow direction in comparison to the experimental observation. The algorithm took boundary values as the particle swarm and updated the position of the particles iteratively to approach the optimization target. The method was tested in a real rat mesenteric network. With random initial boundary values, the method achieved a minimized 9 segments with an inverted flow direction in the network with 546 vessels. Compared with reported literature, the current work has the advantage of a better fit with experimental observations and is more suitable for the boundary estimation problem in pulsatile hemodynamic models due to the experiment-based optimization target selection.

  18. Retinal hemodynamic influence of compound xueshuantong capsule on nonproliferative diabetic retinopathy after laser photocoagulation

    Directory of Open Access Journals (Sweden)

    Yu-Yan Wang

    2014-07-01

    Full Text Available AIM: To observe retinal hemodynamic influence of compound xueshuantong capsule on nonproliferative diabetic retinopathy(NPDRafter laser photocoagulation. METHODS: A total of 41 patients(72 eyeswith NPDR after laser photocoagulation were enrolled in this study. They were all given compound xueshuantong capsule, and used color Doppler flow imaging for detection of retinal hemodynamics. RESULTS: After treatment, patients with retinal blood perfusion significantly improved; central retinal arterial peak systolic velocity(PSV, end-diastolic velocity(EDVand medial velocity(Vmwere increased, while the resistance index(RIdecreased. The difference have statistical significance(PCONCLUSION: Compound xueshuantong capsule can improve retinal blood perfusion for nonproliferative diabetic retinopathy after laser photocoagulation, which is related to improvement of visual prognosis.

  19. 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.

  20. [Dry immersion effects on the mechanisms of metabolic-reflex regulation of hemodynamics during muscular work].

    Science.gov (United States)

    Bravyĭ, Ia R; Bersenev, E Iu; Missina, S S; Borovik, A S; Sharova, A P; Vinogradova, O L

    2008-01-01

    Effects of 4-d dry immersion on metabolic-reflex regulation of hemodynamics were evaluated during local static work (30% of maximum voluntary effort) of the talocrural extensors. One group of immersed test-subjects received low-frequency electrostimulation of leg muscles to offset the immersion effect on EMG of working muscles. Metabolic-reflex regulation was evaluated through comparison of cardiovascular responses to physical tests with and w/o post-exercise vascular occlusion. Immersion vaguely increased heart rate and reduced systolic arterial pressure in resting subjects; however, it did not have a distinct effect on arterial pressure and HR during muscular work or metabolic-reflex potentiation of hemodynamic shifts.

  1. Hemodynamic effects of closure of residual arteriovenous fistulae during in situ graft procedures

    DEFF Research Database (Denmark)

    Laustsen, Jesper; Nielsen, Henriette Svarre; Pedersen, Erik Morre

    2011-01-01

    lower limb ischemia were obtained. Direct measurements of proximal and distal blood pressures in the graft were taken and simultaneous determinations of volume blood flow proximally and distally in the graft with ultrasound transit time technique before and after closure of residual fistulae were made......The objective was to study the intraoperative hemodynamic effects of closure of residual arteriovenous fistulae during in situ saphenous vein graft procedures. Data on 60 residual arteriovenous fistulae in nine patients (five men) with a median age of 74 years (range 64-83 years) with critical....... Closure of a fistula with blood flow around or below 100 mL/min did not increase distal outflow, whereas closure of fistulae with higher blood flow resulted in unpredictable changes in distal outflow. Only fistulae with a blood flow above approximately 100 mL/min may be of hemodynamic significance....

  2. INSTRUMENTAL AND DIAGNOSTIC CRITERIA OF HEMODYNAMIC DISORDERS AND ENDOTHELIAL DYSFUNCTION CORRECTION IN PREGNANTS WITH ARTERIAL HYPERTENSION

    Directory of Open Access Journals (Sweden)

    S. M. Heryak

    2014-12-01

    Conclusions. It was found that the brachial artery ultrasound measuring and occlusive plethysmography procedure by Dietz is an early and safe method of endothelial dysfunction diagnostic in pregnants with hypertension. Doppler ultrasound of blood flow in uterine, umbilical arteries, and middle cerebral arteries of the fetus allows timely diagnosis of the side effect of antihypertensive drugs on the fetus. The therapy of choice for pregnants with Stage II Arterial Hypertension should be based on methyldopa and calcium channel antagonists or selective beta-blockers combination. Highly selective beta-blockers with vasodilative effect (nebivolol hydrochloride and L-arginine (Tivortin allow to prevent perinatal adverse effects of antihypertensive therapy, to correct hemodynamic disorders and endothelial dysfunction in pregnants with arterial hypertension. KEY WORDS: arterial hypertension, uterine-placental hemodynamics, endothelial dysfunction

  3. Cardiac Hemodynamics in the Pathogenesis of Congenital Heart Disease and Aortic Valve Calcification

    Science.gov (United States)

    Nigam, Vishal

    2011-11-01

    An improved understanding of the roles of hemodynamic forces play in cardiac development and the pathogenesis of cardiac disease will have significant scientific and clinical impact. I will focus on the role of fluid dynamics in congenital heart disease and aortic valve calcification. Congenital heart defects are the most common form of birth defect. Aortic valve calcification/stenosis is the third leading cause of adult heart disease and the most common form of acquired valvular disease in developed countries. Given the high incidence of these diseases and their associated morbidity and mortality, the potential translational impact of an improved understanding of cardiac hemodynamic forces is very large. Division of Pediatric Cardiology, Rady Children's Hospital, San Diego

  4. Hemodynamic effects of rapid and slow infusions of manganese chloride and gadolinium-DTPA in dogs

    International Nuclear Information System (INIS)

    Slutsky, R.A.; Peterson, T.; Strich, G.; Brown, J.J.

    1985-01-01

    The acute hemodynamic effects of two paramagnetic contrast materials, manganese chloride and gadolinium-DTPA, were examined in dogs using ultrasonic dimension gauge crystals. Slow infusions (more than 15 minutes) of MnCl 2 or Gd-DTPA via an infusion pump had no significant hemodynamic effects. When given in just over 1 minute, Gd-DTPA produced elevated left ventricular (LV) end diastolic pressure and minor dilation of the ventricle and slowed diastolic filling. MnCl 2 , given rapidly, reduced systemic vascular resistance, resulting in hypotension. With both agents, these side effects waned after 5-10 minutes. It is concluded that both Gd-DTPA and MnCl 2 can be given safely in 0.1-mm/kg doses when administered as a slow, continuous infusion. Slow, intravenous infusion of Gd-DTPA or MnCl 2 is likely to be tolerated well by even severely ill individuals

  5. Clinical Implications of Cluster Analysis-Based Classification of Acute Decompensated Heart Failure and Correlation with Bedside Hemodynamic Profiles.

    Directory of Open Access Journals (Sweden)

    Tariq Ahmad

    Full Text Available Classification of acute decompensated heart failure (ADHF is based on subjective criteria that crudely capture disease heterogeneity. Improved phenotyping of the syndrome may help improve therapeutic strategies.To derive cluster analysis-based groupings for patients hospitalized with ADHF, and compare their prognostic performance to hemodynamic classifications derived at the bedside.We performed a cluster analysis on baseline clinical variables and PAC measurements of 172 ADHF patients from the ESCAPE trial. Employing regression techniques, we examined associations between clusters and clinically determined hemodynamic profiles (warm/cold/wet/dry. We assessed association with clinical outcomes using Cox proportional hazards models. Likelihood ratio tests were used to compare the prognostic value of cluster data to that of hemodynamic data.We identified four advanced HF clusters: 1 male Caucasians with ischemic cardiomyopathy, multiple comorbidities, lowest B-type natriuretic peptide (BNP levels; 2 females with non-ischemic cardiomyopathy, few comorbidities, most favorable hemodynamics; 3 young African American males with non-ischemic cardiomyopathy, most adverse hemodynamics, advanced disease; and 4 older Caucasians with ischemic cardiomyopathy, concomitant renal insufficiency, highest BNP levels. There was no association between clusters and bedside-derived hemodynamic profiles (p = 0.70. For all adverse clinical outcomes, Cluster 4 had the highest risk, and Cluster 2, the lowest. Compared to Cluster 4, Clusters 1-3 had 45-70% lower risk of all-cause mortality. Clusters were significantly associated with clinical outcomes, whereas hemodynamic profiles were not.By clustering patients with similar objective variables, we identified four clinically relevant phenotypes of ADHF patients, with no discernable relationship to hemodynamic profiles, but distinct associations with adverse outcomes. Our analysis suggests that ADHF classification using

  6. Impact of body position on central and peripheral hemodynamic contributions to movement-induced hyperemia: implications for rehabilitative medicine

    OpenAIRE

    Trinity, Joel D.; McDaniel, John; Venturelli, Massimo; Fjeldstad, Anette S.; Ives, Stephen J.; Witman, Melissa A. H.; Barrett-O'Keefe, Zachary; Amann, Markus; Wray, D. Walter; Richardson, Russell S.

    2011-01-01

    This study used alterations in body position to identify differences in hemodynamic responses to passive exercise. Central and peripheral hemodynamics were noninvasively measured during 2 min of passive knee extension in 14 subjects, whereas perfusion pressure (PP) was directly measured in a subset of 6 subjects. Movement-induced increases in leg blood flow (LBF) and leg vascular conductance (LVC) were more than twofold greater in the upright compared with supine positions (LBF, supine: 462 ±...

  7. The Effects of Renal Denervation on Renal Hemodynamics and Renal Vasculature in a Porcine Model.

    Directory of Open Access Journals (Sweden)

    Willemien L Verloop

    Full Text Available Recently, the efficacy of renal denervation (RDN has been debated. It is discussed whether RDN is able to adequately target the renal nerves.We aimed to investigate how effective RDN was by means of functional hemodynamic measurements and nerve damage on histology.We performed hemodynamic measurements in both renal arteries of healthy pigs using a Doppler flow and pressure wire. Subsequently unilateral denervation was performed, followed by repeated bilateral hemodynamic measurements. Pigs were terminated directly after RDN or were followed for 3 weeks or 3 months after the procedure. After termination, both treated and control arteries were prepared for histology to evaluate vascular damage and nerve damage. Directly after RDN, resting renal blood flow tended to increase by 29±67% (P = 0.01. In contrast, renal resistance reserve increased from 1.74 (1.28 to 1.88 (1.17 (P = 0.02 during follow-up. Vascular histopathology showed that most nerves around the treated arteries were located outside the lesion areas (8±7 out of 55±25 (14% nerves per pig were observed within a lesion area. Subsequently, a correlation was noted between a more impaired adventitia and a reduction in renal resistance reserve (β: -0.33; P = 0.05 at three weeks of follow-up.Only a small minority of renal nerves was targeted after RDN. Furthermore, more severe adventitial damage was related to a reduction in renal resistance in the treated arteries at follow-up. These hemodynamic and histological observations may indicate that RDN did not sufficiently target the renal nerves. Potentially, this may explain the significant spread in the response after RDN.

  8. 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.

  9. Time-Series Interactions of Gene Expression, Vascular Growth and Hemodynamics during Early Embryonic Arterial Development.

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    Selda Goktas

    Full Text Available The role of hemodynamic forces within the embryo as biomechanical regulators for cardiovascular morphogenesis, growth, and remodeling is well supported through the experimental studies. Furthermore, clinical experience suggests that perturbed flow disrupts the normal vascular growth process as one etiology for congenital heart diseases (CHD and for fetal adaptation to CHD. However, the relationships between hemodynamics, gene expression and embryonic vascular growth are poorly defined due to the lack of concurrent, sequential in vivo data. In this study, a long-term, time-lapse optical coherence tomography (OCT imaging campaign was conducted to acquire simultaneous blood velocity, pulsatile micro-pressure and morphometric data for 3 consecutive early embryonic stages in the chick embryo. In conjunction with the in vivo growth and hemodynamics data, in vitro reverse transcription polymerase chain reaction (RT-PCR analysis was performed to track changes in transcript expression relevant to histogenesis and remodeling of the embryonic arterial wall. Our non-invasive extended OCT imaging technique for the microstructural data showed continuous vessel growth. OCT data coupled with the PIV technique revealed significant but intermitted increases in wall shear stress (WSS between first and second assigned stages and a noticeable decrease afterwards. Growth rate, however, did not vary significantly throughout the embryonic period. Among all the genes studied, only the MMP-2 and CASP-3 expression levels remained unchanged during the time course. Concurrent relationships were obtained among the transcriptional modulation of the genes, vascular growth and hemodynamics-related changes. Further studies are indicated to determine cause and effect relationships and reversibility between mechanical and molecular regulation of vasculogenesis.

  10. The Effects of Renal Denervation on Renal Hemodynamics and Renal Vasculature in a Porcine Model

    Science.gov (United States)

    Verloop, Willemien L.; Hubens, Lisette E. G.; Spiering, Wilko; Doevendans, Pieter A.; Goldschmeding, Roel; Bleys, Ronald L. A. W.; Voskuil, Michiel

    2015-01-01

    Rationale Recently, the efficacy of renal denervation (RDN) has been debated. It is discussed whether RDN is able to adequately target the renal nerves. Objective We aimed to investigate how effective RDN was by means of functional hemodynamic measurements and nerve damage on histology. Methods and Results We performed hemodynamic measurements in both renal arteries of healthy pigs using a Doppler flow and pressure wire. Subsequently unilateral denervation was performed, followed by repeated bilateral hemodynamic measurements. Pigs were terminated directly after RDN or were followed for 3 weeks or 3 months after the procedure. After termination, both treated and control arteries were prepared for histology to evaluate vascular damage and nerve damage. Directly after RDN, resting renal blood flow tended to increase by 29±67% (P = 0.01). In contrast, renal resistance reserve increased from 1.74 (1.28) to 1.88 (1.17) (P = 0.02) during follow-up. Vascular histopathology showed that most nerves around the treated arteries were located outside the lesion areas (8±7 out of 55±25 (14%) nerves per pig were observed within a lesion area). Subsequently, a correlation was noted between a more impaired adventitia and a reduction in renal resistance reserve (β: -0.33; P = 0.05) at three weeks of follow-up. Conclusion Only a small minority of renal nerves was targeted after RDN. Furthermore, more severe adventitial damage was related to a reduction in renal resistance in the treated arteries at follow-up. These hemodynamic and histological observations may indicate that RDN did not sufficiently target the renal nerves. Potentially, this may explain the significant spread in the response after RDN. PMID:26587981

  11. Hemodynamic effects of aerosol propellants. I. Cardiac depression in the dog.

    Science.gov (United States)

    Simaan, J A; Aviado, D M

    1975-11-01

    The inhalation of fluorocarbons caused a depression of myocardial contractility, aortic hypotension, a decrease in cardiac output and an increase in pulmonary vascular resistance. The minimal concentrations that elicited these changes are as follows: 1% trichlorofluoromethane (FC11); 2.5% dichlorotetrafluoroethane (FC114); and 10% dichlorodifluoromethane (FC12). Inhalation of 20% octafluorocyclobutane (FC318) and difluoroethane (FC152a) did not influence these hemodynamic parameters. As in previous comparisons, the most widely used aerosol propellants are potentially cardiotoxic in the anesthetized dog.

  12. Hemodynamic challenge to early mobilization after cardiac surgery: A pilot study

    Directory of Open Access Journals (Sweden)

    Tiziano Cassina

    2016-01-01

    Full Text Available Background: Active mobilization is a key component in fast-track surgical strategies. Following major surgery, clinicians are often reluctant to mobilize patients arguing that circulatory homeostasis would be impaired as a result of myocardial stunning, fluid shift, and autonomic dysfunction. Aims: We examined the feasibility and safety of a mobilization protocol 12-24 h after elective cardiac surgery. Setting and Design: This observational study was performed in a tertiary nonacademic cardiovascular Intensive Care Unit. Materials and Methods: Over a 6-month period, we prospectively evaluated the hemodynamic response to a two-staged mobilization procedure in 53 consecutive patients. Before, during, and after the mobilization, hemodynamics parameters were recorded, including the central venous oxygen saturation (ScvO 2 , lactate concentrations, mean arterial pressure (MAP, heart rate (HR, right atrial pressure (RAP, and arterial oxygen saturation (SpO 2 . Any adverse events were documented. Results: All patients successfully completed the mobilization procedure. Compared with the supine position, mobilization induced significant increases in arterial lactate (34.6% [31.6%, 47.6%], P = 0.0022 along with reduction in RAP (−33% [−21%, −45%], P 10% and nine of them (17% required treatment. Hypotensive patients experienced a greater decrease in ScvO 2 (−18 ± 5% vs. −9 ± 4%, P = 0.004 with similar changes in RAP and HR. All hemodynamic parameters, but arterial lactate, recovered baseline values after resuming the horizontal position. Conclusions: Early mobilization after cardiac surgery appears to be a safe procedure as far as it is performed under close hemodynamic and clinical monitoring in an intensive care setting.

  13. Hemodynamic stress echocardiography in patients supported with a continuous-flow left ventricular assist device

    DEFF Research Database (Denmark)

    Andersen, Mads Jønsson; Gustafsson, Finn; Madsen, Per Lav

    2010-01-01

    exercise. Exercise induced an increase in cardiac output, systolic pulmonary artery pressure, and diastolic pulmonary artery pressure. Although no changes in left ventricular dimensions or fractional shortening were seen on echocardiography, systolic mitral annular motion (S') increased significantly (in...... parallel with cardiac output) and diastolic E/e' ratio decreased (correlating inversely with diastolic pulmonary artery pressure). These findings emphasize the potential role of exercise echocardiography in studying exercise hemodynamics in LVAD patients....

  14. Remote effects in treated dogs survived acute radiation sickness. Hemodynamics at various times after irradiation

    International Nuclear Information System (INIS)

    Kostesha, N.Ya.; Lopukhova, V.V.

    1993-01-01

    Dogs were exposed to X-radiation at a dose of 15 Gy; part of them received a complex treatment. The morphological of internal organs of control dogs were made before death (on days 4 to 15 after irradiation). The treated dogs were killed 0.5-2 years following irradiation. Hemodynamics normalization was noted in 1.5-2 years in the liver, brain cortex, adrenals, insular tissue of the pancreas, and lymph nodes

  15. B-Type Natriuretic Peptide Reactivity to Mental Stress and Exercise: Role of Obesity and Hemodynamics

    Science.gov (United States)

    2009-08-25

    Clinically, BNP is important in diagnosis/ differential diagnosis in individuals with suspected HF, with a decision cut-point of 100 pg/ml now accepted as...the context of obesity-related disparity in BNP levels or action. Based on the differential hemodynamic reactivity patterns associated with...Arch Intern Med. 2004, 164:2247- 2252. 124 141. Mehra MR, Uber PA, Park MH, et al.: Obesity and suppressed B-type natriuretic peptide levels in

  16. Clofibrate prevents and reverses the hemodynamic manifestations of hyperthyroidism in rats.

    Science.gov (United States)

    Rodríguez-Gómez, Isabel; Cruz, Antonio; Moreno, Juan Manuel; Soler, Agatángelo; Osuna, Antonio; Vargas, Félix

    2008-03-01

    This study analyzed the effects of the chronic administration of clofibrate, a peroxisome proliferator-activated receptor-alpha (PPARalpha) agonist, on the development and established hemodynamic, morphologic, metabolic, and renal manifestations of hyperthyroidism in rats. The prevention study used four groups of male Wistar rats: control, clofibrate (240 mg/kg/day by gavage), T(4)(75 microg thyroxine/rat/day s.c.), and T(4)+clofibrate. All treatments were maintained for 3 weeks. Body weight (BW), tail systolic blood pressure (SBP), and heart rate (HR) were recorded weekly. Finally, temperature, SBP, pulse pressure (PP) and HR were recorded in conscious rats, and morphologic, metabolic, plasma, and renal variables were measured. The reversion study used two groups of rats, T(4)(treated for 6 weeks) and T(4)+clofibrate, measuring their hemodynamic variables and temperature for 3 weeks. T(4) increased BP, HR, PP, and temperature when compared with control rats. Clofibrate prevented and reversed the increase in SBP, HR, PP, and temperature produced by T(4) administration, reduced plasma thyroid hormone levels, and increased plasma thyroid-stimulating hormone values and phenol-uridine diphosphate-glucuronosyl-transferase (UGT) activity. However, clofibrate did not modify the cardiac or renal hypertrophy, polyphagia, polydipsia, or proteinuria of hyperthyroid rats. In normal rats, clofibrate treatment did not significantly change thyroid hormone levels, phenol-UGT activity, or any hemodynamic, morphologic, or renal variables. Chronic clofibrate treatment suppressed the hemodynamic manifestations and increased temperature of hyperthyroidism, an effect that can be produced by direct antithyroid effects. However, clofibrate administration did not modify the morphologic, metabolic, or renal alterations of hyperthyroid rats, indicating specificity in the antithyroid actions of clofibrate.

  17. Occupational exposure to ionizing radiation from the perspective of nursing professionals in hemodynamics

    OpenAIRE

    Adriana Martins Gallo; Fernanda Aparecida Camargo de Lima; Lúcia Margarete dos Reis; Edivaldo Cremer

    2013-01-01

    In order to identify the security measures taken and the control of occupational exposure to ionizing radiation in units of hemodynamic, from the perspective of nursing, this quantitative descriptive study was developed during January and February, 2011. A check-list of binary responses (yes / no) was made based on the legislation and updated literature and it was applied in four hospitals in the northern region of Paraná State. The analysis of the data showed that 29 employees have knowledge...

  18. Does Lower Limb Exercise Worsen Renal Artery Hemodynamics in Patients with Abdominal Aortic Aneurysm?

    OpenAIRE

    Sun, Anqiang; Tian, Xiaopeng; Zhang, Nan; Xu, Zaipin; Deng, Xiaoyan; Liu, Ming; Liu, Xiao

    2015-01-01

    Renal artery stenosis (RAS) and renal complications emerge in some patients after endovascular aneurysm repair (EVAR) to treat abdominal aorta aneurysm (AAA). The mechanisms for the causes of these problems are not clear. We hypothesized that for EVAR patients, lower limb exercise could negatively influence the physiology of the renal artery and the renal function, by decreasing the blood flow velocity and changing the hemodynamics in the renal arteries. To evaluate this hypothesis, pre- and ...

  19. Computational simulation of passive leg-raising effects on hemodynamics during cardiopulmonary resuscitation.

    Science.gov (United States)

    Shin, Dong Ah; Park, Jiheum; Lee, Jung Chan; Shin, Sang Do; Kim, Hee Chan

    2017-03-01

    The passive leg-raising (PLR) maneuver has been used for patients with circulatory failure to improve hemodynamic responsiveness by increasing cardiac output, which should also be beneficial and may exert synergetic effects during cardiopulmonary resuscitation (CPR). However, the impact of the PLR maneuver on CPR remains unclear due to difficulties in monitoring cardiac output in real-time during CPR and a lack of clinical evidence. We developed a computational model that couples hemodynamic behavior during standard CPR and the PLR maneuver, and simulated the model by applying different angles of leg raising from 0° to 90° and compression rates from 80/min to 160/min. The simulation results showed that the PLR maneuver during CPR significantly improves cardiac output (CO), systemic perfusion pressure (SPP) and coronary perfusion pressure (CPP) by ∼40-65% particularly under the recommended range of compression rates between 100/min and 120/min with 45° of leg raise, compared to standard CPR. However, such effects start to wane with further leg lifts, indicating the existence of an optimal angle of leg raise for each person to achieve the best hemodynamic responses. We developed a CPR-PLR model and demonstrated the effects of PLR on hemodynamics by investigating changes in CO, SPP, and CPP under different compression rates and angles of leg raising. Our computational model will facilitate study of PLR effects during CPR and the development of an advanced model combined with circulatory disorders, which will be a valuable asset for further studies. Copyright © 2016 Elsevier Ireland Ltd. All rights reserved.

  20. A framework for the co-registration of hemodynamic forces and atherosclerotic plaque components

    OpenAIRE

    Canton, Gador; Chiu, Bernard; Chen, Huijun; Chen, Yimin; Hatsukami, Thomas S.; Kerwin, William S.; Yuan, Chun

    2013-01-01

    Local hemodynamic forces, such as wall shear stress, are thought to trigger cellular and molecular mechanisms that determine atherosclerotic plaque vulnerability to rupture. Magnetic resonance imaging (MRI) has emerged as a powerful tool to characterize human carotid atherosclerotic plaque composition and morphology, and to identify plaque features shown to be key determinants of plaque vulnerability. Image-based computational fluid dynamics (CFD) has allowed researchers to obtain time-resolv...