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Sample records for bypass vessels influence

  1. Graft patency in off-pump and conventional coronary artery bypass grafting for treatment of triple vessel coronary disease

    Institute of Scientific and Technical Information of China (English)

    胡盛寿; 王小启; 宋云虎; 吕锋

    2003-01-01

    Objective To compare graft patency in off-pump and conventional coronary artery bypass grafting by using the transit time flow meter in the treatment of triple vessel coronary artery disease. Methods Between June 2000 and April 2001, 60 patients with triple vessel coronary artery disease underwent coronary artery bypass grafting. They were divided into two groups: off-pump and conventional coronary artery bypass. All completed grafts were tested intraoperatively using Transit Time Flow Measurement (TTFM). Preoperative and postoperative variables of the two groups were also compared. Results There were no significant differences in sex, age, weight, acute or remote myocardial infarction, hypertension, diabetes and type of bypass grafts between the two groups. The number of bypass grafts and the assisted respiratory time of the off-pump coronary artery bypass grafting (OPCAB) group were significantly less than those of the conventional coronary artery bypass grafting (CCABG) group. The flow and pulsatile index (PI) of the left anterior descending artery bypass grafts and the right coronary artery bypass grafts were not significantly different between the OPCAB and CCABG groups. The flow of OM in the CCABG group with the multiple anastomosis site of sequential grafts was higher than that in the OPCAB group. Diffused narrow coronary artery bypass grafts in both groups had less flow.Conclusion No signficant differences in graft patency were observed in patients with triple vessel coronary artery disease who had undergone OPCAB or CCABG.

  2. The influence of biomaterials on inflammatory responses to cardiopulmonary bypass.

    Science.gov (United States)

    Courtney, J M; Matata, B M; Yin, H Q; Esposito, A; Mahiout, A; Taggart, D P; Lowe, G D

    1996-05-01

    The nature of cardiopulmonary bypass and the complexity of the inflammatory response make the detection and interpretation of a biomaterial influence difficult. However, if mediation of the inflammatory response is considered to be an appropriate clinical goal, alteration to the biomaterial influence merits further investigation.

  3. Five Vessel Coronary Arter Bypass Graft Surgery in a Case with Familial Hypercholesterolemia

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    Sureyya Talay

    2014-08-01

    Full Text Available We report a case of a rare and sypmtomatic familyal hypercholesterolemia case with an end-point of coronary artery bypass surgery at the age of 16. Patient was evaluated at the emergency department with chest pain and discomfort. Physical examination were within normal limits. The electrocardiogram showed a normal sinus rhythm for 108/ min. Arterial blood pressure was 90/60 mmHg. Lungs and heart were clear to auscultation. Patient was under treatment with a prior diagnosis of familial hypercholesterolemia (FH for one year by daily 40 mgs rosuvastatine. A coronary artery angiography was performed for chest pain. Multivessel coronary artery disease was diagnosed with a total occlusion of left anterior descending artery. Transthoracic echocardiography presented a left ventricular (LV ejection fraction 50%, LV diameters 44/26 mm, aneurysm formation at interatrial septum and mild dyskinesia of anterior wall. Thus, a five vessel emergent coronary artery graft bypass surgery was performed at this early age. FH is with a severe elevation in total cholesterol (TC and low density lipoprotein cholesterol (LDL in an autosomal dominant characteristic disorder that approximately occurs in 1 per 500 persons by its heterozygous form. FH is most certainly associated with premature coronary artery disease (CAD with catasthrophic early age results. [Cukurova Med J 2014; 39(4.000: 872-875

  4. Scaling of the direct ECC bypass during LBLOCA reflood phase with direct vessel injection system

    Energy Technology Data Exchange (ETDEWEB)

    Yun, B.J.; Kwon, T.S.; Song, C.H.; Jeong, J.J. [Korea Atomic Energy Research Inst., Taejon (Korea, Republic of); Cho, H.K.; Park, G.C. [Seoul National Univ., Dept. of Nuclear Engineering (Korea, Republic of)

    2001-07-01

    As one of the advanced design features of the Korea next generation reactor, direct vessel injection (DVI) system is being considered instead of conventional cold leg injection (CLI) system. It is known that the DVI system greatly enhances the reliability of the emergency core cooling (ECC) system. However, there is still a dispute on its performance in terms of water delivery to the reactor core during the reflood period of a large-break loss-of-coolant accident (LOCA). Thus, experimental validation is under progress. In this paper, a new scaling method, using time and velocity reduced linear scaling law, is suggested for the design of a scaled-down experimental facility to investigate the direct ECC bypass phenomena in PWR downcomer. (authors)

  5. Intraoperative indocyanine green videoangiography to guide decision making regarding need for vessel bypass: A case report and technical note

    Science.gov (United States)

    Avery, Michael; Chehab, Somar; Wong, John H.; Mitha, Alim P.

    2016-01-01

    Background: Indocyanine green (ICG) videoangiography is an intraoperative technique recently used in vascular neurosurgery to assess the presence or absence of blood flow during critical times of a procedure. These include, but are not limited to, detecting whether daughter branches or perforators are patent after placing a vascular clip or determining whether an aneurysm has been completely isolated from the cerebral circulation after clipping. We present a case of a less-commonly reported application of ICG videoangiography involving the selection of a vessel to act as the bypass recipient once the need is identified during the surgical treatment of a complex intracranial aneurysm. Case Description: A 51-year-old male presented with a ruptured dissecting superior cerebellar artery (SCA) aneurysm that had two branches arising from the dome. Due to the difficult morphology of this aneurysm, a superficial temporal artery to SCA bypass was planned. We used ICG videoangiography to identify the branch that had insufficient retrograde flow via collateral circulation, to which the bypass was performed, followed by the isolation of the aneurysm from the cerebral circulation using permanent surgical clips. Conclusion: Our case represents a possible use of ICG videoangiography during the operative treatment of a difficult aneurysm. Our patient suffered no infarcts postoperatively. In the correct clinical context, this method represents a possible treatment option for complex aneurysms requiring a bypass. PMID:26862459

  6. The influence of stenosis degrees and graft suture position on local hemodynamics of coronary bypass

    Science.gov (United States)

    Totorean, A. F.; Bernad, S. I.; Susan-Resiga, R. F.

    2016-06-01

    Bypass graft failure is mainly caused by intimal hyperplasia (IH) that occurs at the graft anastomosis after coronary artery bypass grafting (CABG) surgery. It has been shown that local hemodynamics influences the process of IH initiation and progression. A main concern at this type of surgery is to increase the graft patency, respectively to improve the local hemodynamics. This paper analyzes the influence of different degree of stenosis severity and graft suture position on graft patency, taking into consideration the local hemodynamics. Bypass configurations with anastomosis angle of 45° were numerically investigated, with respect to wall shear stress and pressure variation. We can assume that in the conditions of our study, different stenosis degrees and position of the graft suture influence the local blood flow conditions, and, nevertheless, the graft patency.

  7. 78 FR 35091 - Requested Administrative Waiver of the Coastwise Trade Laws: Vessel BAD INFLUENCE; Invitation for...

    Science.gov (United States)

    2013-06-11

    ... From the Federal Register Online via the Government Publishing Office DEPARTMENT OF TRANSPORTATION Maritime Administration Requested Administrative Waiver of the Coastwise Trade Laws: Vessel BAD INFLUENCE... of the vessel BAD INFLUENCE is: INTENDED COMMERCIAL USE OF VESSEL: ``6 pack fishing...

  8. Compliant model of a coupled sequential coronary arterial bypass graft: effects of vessel wall elasticity and non-Newtonian rheology on blood flow regime and hemodynamic parameters distribution.

    Science.gov (United States)

    Kabinejadian, Foad; Ghista, Dhanjoo N

    2012-09-01

    We have recently developed a novel design for coronary arterial bypass surgical grafting, consisting of coupled sequential side-to-side and end-to-side anastomoses. This design has been shown to have beneficial blood flow patterns and wall shear stress distributions which may improve the patency of the CABG, as compared to the conventional end-to-side anastomosis. In our preliminary computational simulation of blood flow of this coupled sequential anastomoses design, the graft and the artery were adopted to be rigid vessels and the blood was assumed to be a Newtonian fluid. Therefore, the present study has been carried out in order to (i) investigate the effects of wall compliance and non-Newtonian rheology on the local flow field and hemodynamic parameters distribution, and (ii) verify the advantages of the CABG coupled sequential anastomoses design over the conventional end-to-side configuration in a more realistic bio-mechanical condition. For this purpose, a two-way fluid-structure interaction analysis has been carried out. A finite volume method is applied to solve the three-dimensional, time-dependent, laminar flow of the incompressible, non-Newtonian fluid; the vessel wall is modeled as a linearly elastic, geometrically non-linear shell structure. In an iteratively coupled approach the transient shell equations and the governing fluid equations are solved numerically. The simulation results indicate a diameter variation ratio of up to 4% and 5% in the graft and the coronary artery, respectively. The velocity patterns and qualitative distribution of wall shear stress parameters in the distensible model do not change significantly compared to the rigid-wall model, despite quite large side-wall deformations in the anastomotic regions. However, less flow separation and reversed flow is observed in the distensible models. The wall compliance reduces the time-averaged wall shear stress up to 32% (on the heel of the conventional end-to-side model) and somewhat

  9. Comparative study of on-pump and off-pump coronary bypass surgery in patients with triple-vessel coronary artery disease

    Institute of Scientific and Technical Information of China (English)

    陈鑫; 徐明; 史宏伟; 穆心伟; 陈振强; 邱志兵

    2004-01-01

    Background Studies on selected patients undergoing off-pump versus on-pump coronary artery bypass surgery have produced inconsistent results, especially in patients with multiple coronary artery disease. This study compared the clinical results of on-pump and off-pump coronary bypass surgery in patients with triple-vessel disease.Methods A total of 300 consecutive isolated, multiple coronary artery bypass grafting (CABG) patients were assigned to the off-pump coronary artery bypass (OPCAB, n=150) or CABG with cardiopulmonary bypass (CCABG, n=150) groups. There were no significant differences regarding degree of angina, history of myocardial infarction or diabetes, and presence of left main coronary artery disease between the two groups. Ejection fraction in the OPCAB group before surgery was lower than in the CCABG group (P<0.01). In addition, more patients had a history of stroke and abnormal renal function preoperatively in the OPCAB group(P< 0.01). In OPCAB patients, single deep pericardial stay suture with a sling snared down was used to expose the target vessels, along with a stabilizer and a coronary shunt. A Medi-Stim Butterfly Flowmeter was used to measure blood flow through grafts in both groups.Results No OPCAB patient was converted to the CCABG group. The average numbers of distal anastomoses and the indexes of completeness of revascularization (ICR) were similar in both groups. Postoperative respiratory support time and the volumes of chest tube drainage and of blood transfusions were less in the OPCAB group than in the CCABG group (both P<0.01). The postoperative incidences of pulmonary dysfunction and renal insufficiency were lower in the OPCAB group than in the CCABG group (both P<0.05). There were no significant differences between the two groups in mortality and other causes of morbidity (periopetative myocardial infarction, stroke, atrial fibrillation). Conclusions OPCAB can be applied to patients with triple-vessel coronary artery disease and can

  10. Influence of Cardiopulmonary Bypass on the Interaction of Recombinant Factor VIIa with Activated Platelets

    OpenAIRE

    Kjalke, Marianne; Runge, Marx; Rojkjaer, Rasmus; Steinbruchel, Daniel; Johansson, Pär I

    2009-01-01

    Recombinant factor VIIa (rFVIIa) interacts preferentially with coated platelets characterized by a high exposure of phosphatidyl serine (PS), FV, FVIII, FIX, and FX binding, and fibrinogen. Cardiopulmonary bypass (CPB) is known to impair platelet function. In this study, the influence of CPB on formation of coated platelets and the interaction of rFVIIa with the platelets were studied. Blood was either exposed to a closed CPB circuit or obtained from patients undergoing CPB-assisted cardiac s...

  11. Intraoperative indocyanine green videoangiography to guide decision making regarding need for vessel bypass: A case report and technical note

    Directory of Open Access Journals (Sweden)

    Michael Avery

    2016-01-01

    Conclusion: Our case represents a possible use of ICG videoangiography during the operative treatment of a difficult aneurysm. Our patient suffered no infarcts postoperatively. In the correct clinical context, this method represents a possible treatment option for complex aneurysms requiring a bypass.

  12. Evaluation of the influence of bypass flow gap distribution on the core hot spot in a prismatic VHTR core

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Min-Hwan, E-mail: mhkim@kaeri.re.kr [Korea Atomic Energy Research Institute, 1045 Daedeokdaero, Yoseong, Daejeon 304-353 (Korea, Republic of); Lim, Hong-Sik [Korea Atomic Energy Research Institute, 1045 Daedeokdaero, Yoseong, Daejeon 304-353 (Korea, Republic of)

    2011-08-15

    Highlights: > A procedure to evaluate the local gap size variation between graphite blocks was developed and applied to a prismatic core VHTR. > The analysis for the core bypass flow and hot spot was carried out based on the calculated gap distributions. > The predicted gap size is large enough to affect the flow distribution in the core. > The bypass gap and flow distributions are closely related to the local hot spot temperature and its location. > The core restraint mechanism preventing outward movement of graphite block reduces the bypass gap size and hot spot temperature. - Abstract: Core bypass flow in VHTR is one of the key issues for core thermal margins and efficiency. The bypass flow in the prismatic core varies during core cycles due to the irradiation shrinkage/swelling and thermal expansion of the graphite blocks. A procedure to evaluate the local gap size variation between graphite blocks was developed and applied to a prismatic core VHTR. The influence of the core restraint mechanism on the bypass flow gap was evaluated. The predicted gap size is as much as 8 mm when the graphite block is exposed to its allowable limit of fast neutron fluence. The analysis for the core bypass flow and hot spot was carried out based on the calculated gap distributions. The results indicate that the bypass gap and flow distributions are closely related to the local hot spot and its location and the core restraint mechanism preventing outward movement of the graphite block by a fastening device reduces the bypass gap size, which results in the decrease of maximum fuel temperature not less than 100 deg. C, when compared to the case without it.

  13. Biological artificial vessel graft in distal arterial bypass for treating diabetic lower limb ischemia: a case report

    Institute of Scientific and Technical Information of China (English)

    GU Yong-quan; WU Ying-feng; QI Li-xing; GUO Lian-ri; LI Xue-feng; CUI Shi-jun; TONG Zhu; GUO Jian-ming; ZHANG Jian

    2011-01-01

    A 68-year-old female patient was treated for unhealed ulcer in the fourth toe of the left foot. Clinical examinations identified severe stenosis of the proximal segment and occlusion of the distal segment of the left anterior tibial artery, and occlusion of the left posterior tibial artery and the peroneal artery. The proximal stenotic segment of the left anterior tibial artery was dilated, but the distal occlusive part failed to be re-canalized. Left anterior tibial artery to dorsal pedal artery bypass was performed on the patient with an epoxide-crosslinked, special radicals antigen-sealed, porcine-derived biological graft; debridement of the left 4th digiti pedis was also performed. Postoperation course was uneventful. The pulse of the left dorsal pedal artery was strong. The ankle brachial index (ABI) increased from 0.60 to 1.09. Warfarin and two antiplatelet drugs were given after the operation. Six months after operation, computed tomographic angiogram (CTA)identified the patent graft.

  14. The Evaluation of the Graft Vessels after Coronary Artery Bypasses Graft with the Distal Angiography of DSCT%DSCT数字化血管成像对冠状动脉搭桥术后桥血管的评价

    Institute of Scientific and Technical Information of China (English)

    汪春荣; 沈比先; 高德宏; 刘远健; 谭四平; 陈胜基

    2012-01-01

    Objective: To evaluate the performance of Dual Source CT (DSCT) in the follow up of coronarvartery bypass grafts. Methods: 16 patients with coronary bypass grafts underwent the DSCT coronary angiography(CTA) in Siemens SOMATOM Definition. The proximal and distal anastomosis, the bypass graft itself, and the run-off vessel detected in CTA images were evaluated for every coronary bypass graft, and the native coronary artery segments were evaluated too. The reliability of the DSCT detecting stenoses of the bypass grafts and the native coronary segments would be evaluated. Results: There were 42 bypass grafts in 16 patients with coronary bypass grafts underwent the DSCT coronary angiography(CTA) ,6 bypass grafts of the cases were blocked. All 42 bypass grafts were assessable. Twenty-five bypass grafts of the cases were flowing freely. Nine bypass grafts with insignificant stenosis(≤50%) and 8 bypass grafts with significant stenosis could be dearly displayed(>50%). 36 of 42 coronary bypass grafts including IMA patency in 88.9 (8 / 9), RA in 85.7(6/7) and SVG in 76.9 (20 / 26) were patient. The overall patient rate was 85.7%. Conclusion: Noninvasive evaluating the bypass grafts with DSCT has great potential value in the follow-up.%目的:探讨DSCT数字化血管成像对冠状动脉搭桥术后随访应用价值.方法:采用西门子DSCT(Siemens SOMATOM Definition)对16例行冠状动脉搭桥术后患者行DSCT冠状动脉检查,分别评价CT图像桥血管近远端吻合口、桥血管本身有无狭窄、钙化和吻合口远端引流血管的图像质量及冠状动脉图像质量,评价双源CT诊断桥血管通畅性和冠状动脉是否存在狭窄.结果:DSCT显示16例患者共发现桥血管42根,其中6根闭塞,所有桥血管均可评价.42支桥血管中,25支未见狭窄,9支桥血管狭窄程度≤50%,8支桥血管狭窄程度>50%.搭桥血管通畅率为85.7%(36/42),乳内动脉桥通畅率较高,为88.9%(8/9),肱动脉次之,为85.7%(6/7),大隐

  15. Clinical Outcomes After Drug-Eluting Stents Versus Coronary Artery Bypass Surgery in High Surgical Risk Patients With Left Main or Three-Vessel Coronary Artery Disease

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    Tonga Nfor

    2015-08-01

    Full Text Available Purpose: Previous studies comparing percutaneous coronary intervention (PCI with coronary artery bypass graft surgery (CABG in patients with unprotected left main or three-vessel coronary artery disease (LM-3VD have excluded patients at high surgical risk. We compared clinical outcomes after PCI with drug-eluting stents to CABG in high surgical risk patients with LM-3VD. Methods: Patients with symptomatic LM-3VD who had Society of Thoracic Surgeons (STS-predicted operative mortality > 5% and were undergoing either PCI with drug-eluting stents or CABG at a tertiary care center from January 2009 to December 2010 were enrolled in this nonrandomized prospective study. Results: Mean STS score was 14.5 ± 5.8% for PCI (n=83 vs. 13.6 ± 7.1% for CABG (n=187 (P=0.31. After mean follow-up of 37 months, incidence of the composite primary endpoint (death, myocardial infarction or stroke was 42.2% for PCI and 39.6% for CABG (P=0.69, hazard ratio 1.3, 95% confidence interval 0.5-2.8. There were no differences in the individual components of the primary endpoint between PCI and CABG. Repeat revascularization was 30.1% for PCI vs. 9.6% for CABG (P=0.001. Major adverse cardiac and cerebrovascular event rates were similar between PCI and CABG, 50.6% vs. 42.2%, respectively (P=0.23. Patients in the PCI group were less likely than those in the CABG group to be discharged to a nursing home (12.1% vs. 47.1%, P 5%.

  16. Comparison of drug eluting stent implantation with coronary artery bypass surgery in the treatment of patients with chronic total occlusion and multiple vessel disease

    Institute of Scientific and Technical Information of China (English)

    LIU Wei; ZHU Xiao-Ling; MA Chang-sheng; KANG Jun-ping; DU Xin; CHEN Fang; ZHOU Yu-jie; L(U) Shu-zheng; HUANG Fang-jiong; GU Cheng-xiong

    2011-01-01

    Background In patients with chronic total occlusion (CTO) and multivessel coronary artery disease, the comparison of surgical and the percutaneous revascularization strategies has rarely been conducted. The aim of this study was to compare long term clinical outcomes of drug eluting stent (DES) implantation with coronary artery bypass surgery (CABG)in the patients with CTO and multivessel disease.Methods From a prospective registry of 6000 patients in our institution, we included patients with CTO and multivessel coronary artery disease who underwent either CABG (n=679) or DES (n=267) treatment. Their propensity risk score was used for adjusting baseline differences.Results At a median follow-up of three years, propensity score adjusted Cox regression analysis showed that the rate of major adverse cardiac cerebrovascular events (MACCE) was lower in CABG group (12.7% vs. 24.3%, hazard ratio (HR) 1.969, 95% Cl 1.219-3.179, P=0.006) mainly due to lower rate of target vessel revascularization in CABG group than in DES group (3.1% vs. 17.2%, HR 16.14, 95% CI 5.739-45.391, P <0.001). The incidence of cardiac death or myocardial infarction (composite end point) was not significantly different between these two groups. On multivariate analysis, the significant predictors of MACCE were only the type of revascularization. Age, left ventricular ejection fraction (LVEF), and complete revascularization were identified as significant predictors of composite end points.Conclusions Our study shows that in patients with CTO and multivessel coronary disease, DES can offer comparable long term outcomes in cardiac death and myocardial infraction free survival in comparison with CABG. However, there is an increased rate of MACCE which results from more repeat revascularizations. Obtaining a complete revascularization is crucial for decreasing adverse cardiac events.

  17. Comparison of influence of high thoracic epidural anesthesia and central analgesia on hemodynamic during on-bypass coronary artery bypass grafting

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    V. A. Sobokar

    2015-06-01

    Full Text Available Objective. Despite some advantages, the use of high thoracic epidural anesthesia (HTEA during cardiac operations may be discouraged by fear of adverse hemodynamic effects. Aim. To compare the hemodynamic effects of HTEA and central analgesia (CA during on-bypass CABG. Methods. 132 patients were assigned into two groups – study group (n = 85, where the surgery was carried out under HTEA and control group (n = 47 - where the surgery was carried out under CA. Data of the intraoperative monitoring and trans-oesophageal cardiac ultrasound - cardiac index (CI, stroke index (SI, ejection fraction (EF and index of systemic vascular resistance (ISVR were obtained. Results. After induction and sternotomy patients in the study group had higher EF - 57(53, 65% vs 54 ± 7% (p = 0,013 and 55 ± 8 vs 52 ± 9%, (p = 0,031. After sternotomy CI and SI in the study group were also higher, respectively 2,42 (2,0;3,1 vs 2,23±0,63 l · min-1 · m-2, (p = 0,041 and 43 (34;46 vs 37±10 ml · m-2 (p = 0.014. Conclusion. We concluded that HTEA has advantages over CA by its influence on hemodynamics.

  18. Influence of cerebral blood vessel movements on the position of perivascular synapses

    Science.gov (United States)

    DeFelipe, Javier

    2017-01-01

    Synaptic activity is regulated and limited by blood flow, which is controlled by blood vessel dilation and contraction. Traditionally, the study of neurovascular coupling has mainly focused on energy consumption and oxygen delivery. However, the mechanical changes that blood vessel movements induce in the surrounding tissue have not been considered. We have modeled the mechanical changes that movements of blood vessels cause in neighboring synapses. Our simulations indicate that synaptic densities increase or decrease during vascular dilation and contraction, respectively, near the blood vessel walls. This phenomenon may alter the concentration of neurotransmitters and vasoactive substances in the immediate vicinity of the vessel wall and thus may have an influence on local blood flow. PMID:28199396

  19. The influence of turbulence on aggregation of small particles in agitated vessels

    Science.gov (United States)

    Kusters, Karel Antonius

    The influence of the hydrodynamics in baffled turbine agitated vessels on the turbulent coagulation of small solid particles is studied, with focus on the dependence of the aggregate size on stirrer speed, concentration of solids, destabilizer concentration, and vessel size. The following studies are presented: aggregation theory; hydrodynamics in stirred tanks; numerical particle tracking in a turbine agitated vessel; aggregation kinetics in stirred tanks; and maximum aggregate size in stirred tanks. The application of the model to describe the aggregation process in strirred tanks to experimental conditions other than those tested and to particulate systems with different physical properties is discussed.

  20. Overexpression of isocitrate lyase-glyoxylate bypass influence on metabolism in Aspergillus niger

    DEFF Research Database (Denmark)

    Meijer, Susan Lisette; Otero, José Manuel; Olivares Hernandez, Roberto

    2009-01-01

    glyoxylate would increase, leading to excess formation of malate and succinate compared to the wild-type. However, metabolic network analysis showed that an increased icl expression did not result in an increased glyoxylate bypass flux. The analysis did show a global response with respect to gene expression......In order to improve the production of succinate and malate by the filamentous fungus Aspergillus niger the activity of the glyoxylate bypass pathway was increased by over-expression of the isocitrate lyase (icl) gene. The hypothesis was that when isocitrate lyase was up-regulated the flux towards......, leading to an increased flux through the oxidative part of the TCA cycle. Instead of an increased production of succinate and malate, a major increase in fumarate production was observed. The effect of malonate, a competitive inhibitor of succinate dehydrogenase (SDH), on the physiological behaviour...

  1. Numerical analysis of bypass model geometrical parameters influence on pulsatile blood flow

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    Jonášová A.

    2011-06-01

    Full Text Available The present study is focused on the analysis of pulsatile blood flow in complete idealized 3D bypass models in dependence on three main geometrical parameters (stenosis degree, junction angle and diameter ratio. Assuming the blood to be an incompressible Newtonian fluid, the non-linear system of Navier-Stokes equations is integrated in time by a fully implicit second-order accurate fractional-step method. The space discretization is performed with the help of the cell-centred finite volume method formulated for unstructured tetrahedral grids. In order to model a realistic coronary blood flow, a time-dependent flow rate taken from corresponding literature is considered. For the analysis of obtained numerical results, special emphasis is placed on their comparison in the form of velocity isolines at several selected cross-sections during systolic and diastolic phases. The remainder of this paper is devoted to discussion of walls shear stress distribution and its oscillatory character described by the oscillatory shear index with regard to areas prone to development of intimal hyperplasia or to thrombus formation.

  2. Multivariate Analysis of Factors Influencing Length of Hospital Stay after Coronary Artery Bypass Surgery in Tehran, Iran

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    Amin Torabipour

    2016-03-01

    Full Text Available Length of hospital stay (LOS is a key indicator for hospital management. Reducing hospital stay is a priority for all health systems. We aimed to determine the length of hospital stay following Coronary Artery Bypass Surgery (CABG based on its clinical and non-clinical factors. A cross-sectional study of 649 consecutive patients who underwent coronary artery bypass graft surgery was conducted in Imam Khomeini and Shariati university hospitals, Tehran, Iran. Data was analyzed by using non-parametric univariate tests and multiple linier regression models. Thirty seven independent variables including pre-operative, intra-operative and post-operative variables were analyzed. Finally, an appropriate model was constructed based on the associated factors. The results showed that 70.3% of the patients were male, and the mean age of the patients was 59.3 ± 10.4 years. The Mean (±SD and median of the LOS were 11.7 ± 7.1 and 9 days, respectively. Of 37 investigated variables, 24 qualitative and quantitative variables were significantly associated with length of stay (p<0.05. Multiple linear regression analysis showed that independent variables including age, medical insurance type, body mass index, and prior myocardial infarction; admission day, admission season, Cross-clamp time, pump usage, admission type, the number of laboratory tests and the number of specialty consultation had more effect on the hospital stay. We concluded that some significant factors influencing hospital stay after CABG were predictable and modifiable by hospital managers and decision makers to manage hospital beds.

  3. PILOT STUDY RESULTS OF THE INFLUENCE OF CITICOLINE AND PIRIBEDIL ON COGNITIVE FUNCTION IN PATIENTS WITH ISCHEMIC HEART DISEASE AFTER CORONARY ARTERY BYPASS SURGERY

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    M. M. Petrova

    2015-01-01

    Full Text Available Aim. To reveal cognitive deficit after coronary artery bypass, the influence of citicoline, piribedil on the state of higher cerebral functions in the early and late periods after surgery.Material and methods. The study included 94 patients with ischemic heart disease. All patients were divided into 3 groups. Patients of the first group (n=30 were prescribed citicoline as a cerebral neuroprotective drug. Patients of the second group (n=32 had piribedil in addition to standard therapy. Patients of the control group (n=32 had only a standard treatment without any neuroprotective drugs. All patients underwent coronary artery bypass surgery. The cognitive function was assessed before, 10 days after and six months after coronary artery bypass.Results. Patients of group 1 and 2 had achieved pre-surgical levels of cognitive tests results 6 months after coronary artery bypass. The control group had achieved initial levels only in three tests: visual memory (immediate simulation; p=0.008, categorical association (p=0.002, clock drawing test (Wilcoxon test; p=0,005, while other indices were reduced in comparison with the initial ones.Conclusion. The obtained results allow considering the studied drugs as a protectors of cognitive function after surgery. Randomized controlled double-blind studies on large samples are needed to confirm these results.

  4. PILOT STUDY RESULTS OF THE INFLUENCE OF CITICOLINE AND PIRIBEDIL ON COGNITIVE FUNCTION IN PATIENTS WITH ISCHEMIC HEART DISEASE AFTER CORONARY ARTERY BYPASS SURGERY

    Directory of Open Access Journals (Sweden)

    M. M. Petrova

    2015-09-01

    Full Text Available Aim. To reveal cognitive deficit after coronary artery bypass, the influence of citicoline, piribedil on the state of higher cerebral functions in the early and late periods after surgery.Material and methods. The study included 94 patients with ischemic heart disease. All patients were divided into 3 groups. Patients of the first group (n=30 were prescribed citicoline as a cerebral neuroprotective drug. Patients of the second group (n=32 had piribedil in addition to standard therapy. Patients of the control group (n=32 had only a standard treatment without any neuroprotective drugs. All patients underwent coronary artery bypass surgery. The cognitive function was assessed before, 10 days after and six months after coronary artery bypass.Results. Patients of group 1 and 2 had achieved pre-surgical levels of cognitive tests results 6 months after coronary artery bypass. The control group had achieved initial levels only in three tests: visual memory (immediate simulation; p=0.008, categorical association (p=0.002, clock drawing test (Wilcoxon test; p=0,005, while other indices were reduced in comparison with the initial ones.Conclusion. The obtained results allow considering the studied drugs as a protectors of cognitive function after surgery. Randomized controlled double-blind studies on large samples are needed to confirm these results.

  5. The influence of the residual stress in silicone tubes in the calibration methods of roller pumps used in cardiopulmonary bypass.

    Science.gov (United States)

    Vieira, Francisco Ubaldo; Vieira, Reinaldo Wilson; Antunes, Nilson; Petrucci, Orlando; de Oliveira, Pedro Paulo; Silveira Filho, Lindemberg da Mota; Vilarinho, Karlos Alexandre de Sousa; de Oliveira Severino, Elaine Soraya Barbosa

    2010-01-01

    The rotation of rollers in cardiopulmonary bypass pumps propels the blood through various devices to reach the patient. Very occlusive settings may squeeze red blood cells, whereas a nonocclusive setting may result in retrograde flow. Occlusion of roller pumps may be regulated either by measuring the drop rate or by dynamic calibration. This study evaluated the influence of silicone tubing residual stress found on pump regulation. Silicone tubes obtained from two different suppliers were used in 6-inch DeBakey roller pumps. The variations occurring over time in the measurements of drop rate, dynamic calibration, and tube residual stress were analyzed. Covariance analysis of the four linear regressions has shown a progressive and accentuated reduction in drop rate (p 0.56). This reduction in drop rate measurements may affect the regulation of the pumps before surgical procedures. One probable cause for this reduction is the residual stress found in the silicone tubes. Settings based on the dynamic calibration process tended to be repeated over time. Simple linear regression test (angular coefficient equals zero) has shown a p > 0.79 showing no interference of the silicone tubes residual stress on dynamic calibration, suggesting that one should use this method to calibrate roller pumps.

  6. The influence of the anastomosis angle on the hemodynamics in the distal anastomosis in the infrainguinal bypass: an in vitro study.

    Science.gov (United States)

    Grus, T; Grusová, G; Lambert, L; Banerjee, R; Matěcha, J; Mlček, M

    2016-11-08

    The geometric shape of the distal anastomosis in an infrainguinal bypass has an influence on its durability. In this article, we compared three different angles of the anastomosis with regard to the hemodynamics. Three experimental models of the distal infrainguinal anastomosis with angles of 25°, 45°, and 60° respectively were constructed according to the similarity theory to assess flow in the anastomoses using particle image velocimetry and computational fluid dynamics. In the toe, heel, and floor of the anastomosis that correspond to the locations worst affected by intimal hyperplasia, adverse blood flow and wall shear stress were observed in the 45° and 60° models. In the 25° model, laminar blood flow was apparent more peripherally from the anastomosis. In conclusions, decreasing the distal anastomosis angle in a femoropopliteal bypass results in more favorable hemodynamics including the flow pattern and wall shear stress in locations susceptible to intimal hyperplasia.

  7. The Influence for Heart and Blood Vessel of Resperdone%利培酮对心血管的影响

    Institute of Scientific and Technical Information of China (English)

    丁智平; 戴兴海; 廖慧珍

    2002-01-01

    Objective To research the influence of the Risperidone for heart and blood vessel and to contral for Clozapine. Method Schizophrenic patients who were in hospital and conform to diagnostic criteria of CCMD- 2- R were been divided Risperidone group and Clozapine group. Two group patients were been examined EKG before and after treatment one、two、three months. Results The influence for heart and blood vessel of Risperidone group were mainly Sinus bradycardia and T wave change but lower for Clozapine group. The influence was associated with the time of taking the drugs Conclusion There was influence on heart and blood vessel of Risperidone but the extend of influencc was lower for Clozapine and must give rise to pay attention.

  8. Flap repair for vascular prosthesis exposure after artificial blood vessel bypass surgery for critical limb ischemia%皮瓣重建修复下肢动脉旁路移植术后人工血管外露

    Institute of Scientific and Technical Information of China (English)

    吴巍巍; 吴昊; 曾昂; 白明; 曾嵘; 陈宇; 刘昌伟

    2013-01-01

    Objective To investigate the effectiveness of flap repair for vascular prosthesis exposure after the artificial blood vessel bypass surgery for critical limb ischemia.Methods From August 2007 to December 2011,bypass surgery with vascular prosthetic grafts were performed in 192 patients with critical limb ischemia.Five patients among them (2.6%) suffered from vascular prosthesis exposure 6 to 13 days after the previous surgery,including 4 males and 1 female,with a median age of 68 years (arranged from 52 to 81 years).The surgical managements included surgical debridement and local flap or transferred muscle-cutaneous flap repair to preserve the prosthetic vascular grafts.Three patients underwent Z-plasty with local flap repair,while 2 patients underwent transferred rectus abdominis or rectus femoris muscle flap repair of the wounds.Results After the surgery,prosthetic vascular graft was successfully preserved in 4 of the 5 cases with first intention healing.At a median follow-up of 38 months (arranged from 5 to 57 months),all the 4 limbs were salvaged with patent of the prosthetic grafts.One flap failed to heal and the prosthetic graft had to be removed due to infection and hemorrhage.An above-knee-amputation was performed due to severe limb ischemia.Conclusions The vascular prosthesis exposure is often a disaster after artificial blood vessel bypass surgery for critical limb ischemia.Local flap or transferred muscle-cutaneous flap repair is an effective surgical management to salvage the exposed graft and the affected limb.%目的 探讨皮瓣重建技术修复因重症下肢缺血行人工血管旁路移植术后人工血管外露的可行性.方法 回顾性分析2007年8月至201 1年12月诊治的192例下肢人工血管旁路移植术后患者,其中5例(2.6%)在前次术后6~13d发生人工血管外露,包括男性4例,女性1例,年龄52~81岁,中位年龄68岁.外科处理主要包括局部清创及保留移植物的任意皮

  9. Optic chiasm compression from mass effect and thrombus formation following unsuccessful treatment of a giant supraclinoid ICA aneurysm with the Pipeline device: open surgical bailout with STA-MCA bypass and parent vessel occlusion.

    Science.gov (United States)

    Abla, Adib A; Zaidi, Hasan A; Crowley, R Webster; Britz, Gavin W; McDougall, Cameron G; Albuquerque, Felipe C; Spetzler, Robert F

    2014-07-01

    Pipeline Embolization Devices (PEDs) have been shown to be effective for intracranial internal carotid artery (ICA) aneurysms, and are now approved by the FDA specifically for this use. Potential pitfalls, however, have not yet been described in the pediatric neurosurgical literature. The authors report on a 10-year-old boy who presented to the Barrow Neurological Institute after progressive visual decline. He had undergone placement of a total of 7 telescoping PEDs at another facility for a large ICA aneurysm. Residual filling of the aneurysm and significant expansion of intraaneurysmal thrombus with chiasmal compression on admission images were causes for concern. The patient underwent a surgical bailout with a superficial temporal artery-middle cerebral artery bypass, with parent artery occlusion. Postoperative vascular imaging was notable for successful occlusion of the parent vessel, with no evidence of filling of the aneurysm. Reports on the pitfalls of PEDs in the neurosurgical literature are scarce. To the authors' knowledge this represents the first paper describing a successful open surgical bailout for residual aneurysmal filling and expansion of thrombus after placement of a PED.

  10. Dacron or PTFE for above-knee femoropopliteal bypass

    DEFF Research Database (Denmark)

    Jensen, Leif P.; Lepäntalo, M.; Fossdal, J.E.

    2007-01-01

    OBJECTIVES: To compare polytetrafluorethylene (PTFE) and polyester grafts (Dacron) for above knee femoropopliteal bypass. DESIGN: Multicenter randomised clinical trial. MATERIAL AND METHODS: 427 patients were randomised between 6mm Dacron (Uni-Graft, B. Braun Melsungen AG, 34212 Melsungen, Germany......) and PTFE (Goretex, W. L. Gore & Ass. Inc., Newark DE 19711, USA) above-knee femoropopliteal bypass grafts within 13 centres in Denmark (n=261), Norway (n=113) & Finland (n=53) between 1993 and 1998. Fourteen (3%) patients were excluded, leaving 413 patients with 208 Dacron and 205 PTFE grafts for analysis......-brachial pressures or imaging in case of doubt. RESULTS: The two-year primary patency rates for Dacron and PTFE were 70% and 57% (p=0.02), whereas the secondary patency rates were 76% and 65% (p=0.04), respectively. Primary patency at two years was significantly influenced by the number of patent crural vessels (two...

  11. Influences of physical properties of two-phase mixture on void fraction in an annular vessel

    Institute of Scientific and Technical Information of China (English)

    LI Xiao-Ming; BI Qin-Cheng; FENG Quan-Ke; CHEN Ting-Kuan; DU She-Jiao

    2004-01-01

    To keep the void fraction of two-phase hydrogen in the moderator cell of the cold neutron source (CNS)of China Advanced Research Reactor (CARR) to a specified range, an annular vessel with the same size as the actual moderator cell was used as test section. Deionized water and alcohol, sucrose, and sodium chloride solutions with different concentrations were used as working fluid to find out influences of physical properties, such as density, viscosity and surface tension, of the two-phase mixture on void fraction. The tests proved that the ratio of surface tension to density of liquid phase has great influence on void fraction: the larger the ratio, the smaller the void fraction.Since the ratio of surface tension to density of Freon 113 is lower than that of liquid hydrogen, Freon 113 can be used as a working fluid to study the void fraction in the two-phase hydrogen thermosiphon loop in the CNS of CARR and the results will be conservative.

  12. Extra-intracranial standard bypass in the elderly

    DEFF Research Database (Denmark)

    Sandow, Nora; von Weitzel-Mudersbach, Paul; Rosenbaum, Sverre;

    2013-01-01

    Patients with chronic atherosclerotic vessel occlusion and cerebrovascular hemodynamic insufficiency may benefit from extra-intracranial (EC-IC) bypass surgery. Due to demographic changes, an increasing number of elderly patients presents with cerebrovascular hemodynamic insufficiency. So far......, little data for EC-IC bypass surgery in elderly patients suffering occlusive cerebrovascular disease are available. We therefore designed a retrospective study to address the question whether EC-IC bypass is a safe and efficient treatment in a patient cohort ≥70 years....

  13. White matters - The influence of cerebral small-vessel disease on depression, cognition and functioning

    NARCIS (Netherlands)

    Grool, A.M.

    2012-01-01

    Depression and cognitive impairment are highly prevalent in later life, and frequently co-occur. One of the possible mechanisms that may underlie both conditions is the presence of cerebral small-vessel disease. The presence of cerebral small-vessel disease is strongly associated with common vascula

  14. Influence of recombinant human brain natriuretic peptide on myocardial enzymes, serum cardiac function indexes and oxygen metabolism of patients with open heart surgery with cardiopulmonary bypass

    Institute of Scientific and Technical Information of China (English)

    Shu-Tian Song; Ming Yang; Kun-Peng Li; Juan Xu; Chuan-Ming Bai; Ji-Wu Zhou

    2016-01-01

    Objective:To investigate and analyze the influence of recombinant human brain natriuretic peptide on myocardial enzymes, serum cardiac function indexes and oxygen metabolism of patients with open heart surgery with cardiopulmonary bypass.Methods:A total of 42 patients with open heart surgery with cardiopulmonary bypass during the period of June 2014 to January 2016 were randomly divided into the control group of 21 cases and the observation group of 21 cases. The control group was treated with routine postoperative treatment, and the observation group was treated with recombinant human brain natriuretic peptide on the basic treatment of control group, then the myocardial enzymes, serum cardiac function indexes and oxygen metabolism indexes of the two groups before the surgery and at 2 h, 12 h and 24 h after the surgery were respectively detected and compared.Results: There were no significant difference in myocardial enzymes, serum cardiac function indexes and oxygen metabolism indexes between two groups before the surgery (allP>0.05), while the myocardial enzymes and serum cardiac function indexes of the observation group at 2 h ,12 h and 24 h after the surgery were all significantly lower than those of control group, the oxygen metabolism indexes were significantly better than the levels of control group (allP<0.05).Conclusions:The recombinant human brain natriuretic peptide can effectively improve the myocardial enzymes, serum cardiac function indexes and oxygen metabolism state of patients with open heart surgery with cardiopulmonary bypass, and it has application value for the patients with the surgery is higher.

  15. Influence of residual stresses on failure pressure of cylindrical pressure vessels

    Institute of Scientific and Technical Information of China (English)

    M. Jeyakumar; T. Christopher

    2013-01-01

    The utilization of pressure vessels in aerospace applications is manifold. In this work, finite element analysis (FEA) has been carried out using ANSYS software package with 2D axisym-metric model to access the failure pressure of cylindrical pressure vessel made of ASTM A36 carbon steel having weld-induced residual stresses. To find out the effect of residual stresses on failure pressure, first an elasto-plastic analysis is performed to find out the failure pressure of pressure vessel not having residual stresses. Then a thermo-mechanical finite element analysis is performed to assess the residual stresses developed in the pressure vessel during welding. Finally one more elasto-plastic analysis is performed to assess the effect of residual stresses on failure pressure of the pressure vessel having residual stresses. This analysis indicates reduction in the failure pressure due to unfavorable residual stresses.

  16. Cerebral autoregulation and flow/metabolism coupling during cardiopulmonary bypass: the influence of PaCO/sub 2/

    Energy Technology Data Exchange (ETDEWEB)

    Murkin, J.M.; Farrar, J.K.; Tweed, W.A.; McKenzie, F.N.; Guiraudon, G.

    1987-09-01

    Measurement of /sup 133/Xe clearance and effluent cerebral venous blood sampling were used in 38 patients to determine the effects of cardiopulmonary bypass, and of maintaining temperature corrected or noncorrected PaCO/sub 2/ at 40 mm Hg on regulation of cerebral blood flow (CBF) and flow/metabolism coupling. After induction of anesthesia with diazepam and fentanyl, mean CBF was 25 ml X 100 g-1 X min-1 and cerebral oxygen consumption, 1.67 ml X 100 g-1 X min-1. Cerebral oxygen consumption during nonpulsatile cardiopulmonary bypass at 26 degrees C was reduced to 0.42 ml X 100 g-1 X min-1 in both groups. CBF was reduced to 14-15 ml X 100 g-1 X min-1 in the non-temperature-corrected group (n = 21), was independent of cerebral perfusion pressure over the range of 20-100 mm Hg, but correlated with cerebral oxygen consumption. In the temperature-corrected group (n = 17), CBF varied from 22 to 32 ml X 100 g-1 X min-1, and flow/metabolism coupling was not maintained (i.e., CBF and cerebral oxygen consumption varied independently). However, variation in CBF correlated significantly with cerebral perfusion pressure over the pressure range of 15-95 mm Hg. This study demonstrates a profound reduction in cerebral oxygen consumption during hypothermic nonpulsatile cardiopulmonary bypass. When a non-temperature-corrected PaCO/sub 2/ of approximately 40 mm Hg was maintained, CBF was lower, and analysis of pooled data suggested that CBF regulation was better preserved, i.e., CBF was independent of pressure changes and dependent upon cerebral oxygen consumption.

  17. 冠状动脉三支病变患者不同血运重建策略的预后比较%COMPARISON OF PERCUTANEOUS CORONARY INTERVENTION WITH CORONARY ARTERY BYPASS GRAFTING FOR TRIPLE-VESSEL DISEASE

    Institute of Scientific and Technical Information of China (English)

    李三军; 王立军; 江时森; 刘广彬

    2011-01-01

    [目的]比较冠状动脉三支病变患者经皮冠状动脉介入治疗(percutaneous corollary intervention,PCI)和冠状动脉旁路移植术(coronary artery bypass grafting,CABG)的预后.[方法]回顾性分析了首次行血运重建治疗的冠状动脉三支病变患者233例,其中PCI组160例,CABG组73例,比较两组患者2年的不良心脑血管事件(包括全因死亡;全因死亡和非致死性卒中/心肌梗死联合终点;再次血运重建术).[结果]CABG组的2年再次血运重建率低于PCI组,但由于术后院内死亡率较高导致CABG组2年全因死亡发生率高于PCI组(P<0.05),2年主要不良心脑血管事件发生率(major adverse cardiac and cerebrovascular events,MACCE)、2年全因死亡和非致死性卒中/心肌梗死联合终点发生率两组间差异无统计学意义(P>0.05).[结论]冠状动脉三支病变患者2年联合终点事件发生率两组间并无差异,但PCI组的2年再次血运重建率仍高于CABG组.%[Objective] To investigate the clinical outcomes of percutaneous coronary intervention (PCI) and coronary artery bypass grafting (CABG) in patients with triple-vessel disease. [Methods] Patients with triple-vesscl disease who underwent PIC (n=160) or CABG (n=73) firstly were included. We compared adverse outcomes (death; a composite components of death, stroke, and myocardial infarction; and repeat revascularization) during the 2-year period after revascularization. [ Results] Compared with the PCI group, the CABG group had lower rate of repeat revascularization, and higher rate of death from any cause due to the higher in-hospital mortality (P < 0.05) ; the rates of major adverse cardiac and cerebrovascular events (MACCE) and the composite components of death, stroke, and myocardial infarction showed no differences between the two groups (P> 0.05). [Conclusion] The rates of the composite components of death, stroke, and myocardial infarction do not differ significantly between the two groups

  18. AGE AND GENDER MAY INFLUENCE THE RESULTS OF ROUX-EN-Y GASTRIC BYPASS? Metabolic syndrome parameters

    Directory of Open Access Journals (Sweden)

    Stephan Garcia ANDRADE-SILVA

    2014-09-01

    Full Text Available Context Severe obesity affects the body favoring the development of serious diseases, including hypertension, diabetes mellitus, atherosclerosis and non alcoholic fatty liver disease. Bariatric procedures increased in Brazil in the last decade. Objectives The purpose of this study was to verify if gender and age in date of procedure resulted significant differences in metabolic syndrome parameters after surgery. Methods The study involved 205 medical records of adult patients undergoing Roux-en-Y gastric bypass, stratified by gender and age groups and followed one year by a multidisciplinary team. Results It was observed significant decrease in body mass index, fasting glucose and insulin at all ages and both genders. Lipid profile showed significant improvements except high density lipoprotein cholesterol. Ectopic fat in the liver has decreased after 6 months in patients classified with steatosis at baseline. Patients classified as hypertensive blood pressure levels decreased 6 months after surgical intervention. Conclusions Roux-en-Y gastric bypass proved to be an important tool in remission of metabolic syndrome parameters. The reduction of body mass accompanied to decrease in insulin resistance resulted in lower prevalence of comorbidities associated with obesity. The benefits were similar and extended both genders and all age groups between 18 and 65 years old.

  19. Coronary Artery Bypass Surgery

    Science.gov (United States)

    ... t help, you may need coronary artery bypass surgery. The surgery creates a new path for blood to flow ... more than one bypass. The results of the surgery usually are excellent. Many people remain symptom-free ...

  20. Coronary Artery Bypass

    Science.gov (United States)

    ... to 3 days in the Intensive Care Unit (ICU). Life After Bypass After bypass surgery, your doctor will recommend that you join a cardiac rehabilitation program. These programs help you make lifestyle changes ...

  1. Gastric bypass surgery

    Science.gov (United States)

    ... Roux-en-Y; Weight-loss surgery - gastric bypass; Obesity surgery - gastric bypass ... bypass surgery is not a quick fix for obesity. It will greatly change your lifestyle. After this surgery, you must eat healthy foods, control portion sizes of ...

  2. Influence of physical fitness and activity behavior on retinal vessel diameters in primary schoolchildren.

    Science.gov (United States)

    Imhof, K; Zahner, L; Schmidt-Trucksäss, A; Faude, O; Hanssen, H

    2016-07-01

    Retinal vessel alterations have been shown to be associated with cardiovascular risk factors and physical inactivity as early as childhood. In this context, the analysis of physical activity in children has solely been based on questionnaire assessments. The study aimed to examine the association of physical fitness performance and self-reported physical activity with retinal vessel diameters in young children. Three hundred ninety-one primary schoolchildren [7.3 years (SD 0.4)] were examined in this cross-sectional study. The primary outcome was endurance performance measured with the 20-m shuttle run. The additional tests consisted of a 20-m sprint, jumping sidewards and balancing backwards. Retinal microcirculation was assessed using a static retinal vessel analyzer. Parents completed questionnaires about physical and sedentary activities. Endurance performance was associated with narrower retinal venular diameters [-0.9 (95%CI: -1.8; -0.1) measuring units (mu)/ unit shuttle run, P = 0.04] and a higher arteriolar to venular ratio [0.003 (-0.001; 0.006)/unit shuttle run, P = 0.06]. The sprint performance was associated with narrower retinal arterioles [4.7 (0.8; 8.6) mu/unit sprint, P = 0.02]. Indoor playing activity correlated with narrower retinal venules [-0.04 (-0.07; -0.01) mu/per unit, P = 0.02]. Our data suggest that objectively measured endurance performance relates with better retinal vessel health in early childhood.

  3. Pressure distension in leg vessels as influenced by prolonged bed rest and a pressure habituation regimen.

    Science.gov (United States)

    Eiken, Ola; Mekjavic, Igor B; Kounalakis, Stylianos N; Kölegård, Roger

    2016-06-15

    Bed rest increases pressure distension in arteries, arterioles, and veins of the leg. We hypothesized that bed-rest-induced deconditioning of leg vessels is governed by the removal of the local increments in transmural pressure induced by assuming erect posture and, therefore, can be counteracted by intermittently increasing local transmural pressure during the bed rest. Ten men underwent 5 wk of horizontal bed rest. A subatmospheric pressure (-90 mmHg) was intermittently applied to one lower leg [pressure habituation (PH) leg]. Vascular pressure distension was investigated before and after the bed rest, both in the PH and control (CN) leg by increasing local distending pressure, stepwise up to +200 mmHg. Vessel diameter and blood flow were measured in the posterior tibial artery and vessel diameter in the posterior tibial vein. In the CN leg, bed rest led to 5-fold and 2.7-fold increments (P pressure-distension and flow responses, respectively, and to a 2-fold increase in tibial vein pressure distension. In the PH leg, arterial pressure-distension and flow responses were unaffected by bed rest, whereas bed rest led to a 1.5-fold increase in venous pressure distension. It thus appears that bed-rest-induced deconditioning of leg arteries, arterioles, and veins is caused by removal of gravity-dependent local pressure loads and may be abolished or alleviated by a local pressure-habituation regimen.

  4. The influence of low and moderate carotid stenosis on neurophysiologic status of patients undergoing on-pump coronary artery bypass grafting

    Directory of Open Access Journals (Sweden)

    Olga eTrubnikova

    2012-01-01

    Full Text Available Background: Significant (>70% extracranial stenosis of the internal carotid artery (ICA is a known risk factor for brain damage in patients with coronary heart disease (CHD undergoing coronary artery bypass grafting (CABG. There is no clear evidence of the low and moderate ICA stenoses influence on the neurophysiologic status of patients after CABG. This work was aimed at studying the influence ICA stenoses (<50% on the dynamics of neurophysiologic status in patients undergone CABG. Methods: We examined neurophysiologic functions and EEG in CHD patients (N=45 aged from 45 to 70 years. All patients were divided into two groups: with ICA stenosis (n=20 and without one (n= 25. Results: It was established that the group ICA stenosis had a negative dynamics of neurophysiologic status 6 months follow-up after CABG compared with patients without stenosis. Conclusions: Our results suggest that the presence of low and moderate ICA stenosis is one of the factors affecting the neurophysiologic status of CHD patients. It has been assumed that the patients with ≤50% ICA stenoses constitute a high-risk group for cerebral complications after on-pump CABG.

  5. Crack growth tests on a ferritic reactor pressure vessel steel under the simultaneous influence of simulated BWR coolant and irradiation

    Energy Technology Data Exchange (ETDEWEB)

    Hoffmann, H. [VGB PowerTech e.V., Essen (Germany); Huettner, F. [Hamburgische Electricitaets-Werke AG, Hamburg (Germany); Ilg, U. [EnBW Kraftwerke AG, Philippsburg (Germany); Wachter, O. [E.ON Kernkraft GmbH, Hannover(Germany); Widera, M. [RWE Power AG, Essen (Germany); Brozova, A.; Ernestova, M.; Kysela, J.; Vsolak, R. [Nuclear Research Institute Rez plc (Czech Republic)

    2004-07-01

    Crack growth tests under constant load with initial in-situ cycling were performed on the low alloy reactor pressure vessel (RPV) steel 22 NiMoCr 3 7 (A 508 Cl. 2) with the goal to determine crack growth rates of irradiated and non-irradiated steel under the simultaneous influence of simulated BWR coolant and irradiation. The tests were performed under conditions as near as possible to operational conditions in a commercial BWR reactor. The research results are summarized and are compared with international data. (orig.)

  6. Expression of the growth factor progranulin in endothelial cells influences growth and development of blood vessels: a novel mouse model.

    Science.gov (United States)

    Toh, Huishi; Cao, Mingju; Daniels, Eugene; Bateman, Andrew

    2013-01-01

    Progranulin is a secreted glycoprotein that regulates cell proliferation, migration and survival. It has roles in development, tumorigenesis, wound healing, neurodegeneration and inflammation. Endothelia in tumors, wounds and placenta express elevated levels of progranulin. In culture, progranulin activates endothelial proliferation and migration. This suggested that progranulin might regulate angiogenesis. It was, however, unclear how elevated endothelial progranulin levels influence vascular growth in vivo. To address this issue, we generated mice with progranulin expression targeted specifically to developing endothelial cells using a Tie2-promoter/enhancer construct. Three Tie2-Grn mouse lines were generated with varying Tie2-Grn copy number, and were called GrnLo, GrnMid, and GrnHi. All three lines showed increased mortality that correlates with Tie2-Grn copy number, with greatest mortality and lowest germline transmission in the GrnHi line. Death of the transgenic animals occurred around birth, and continued for three days after birth. Those that survived beyond day 3 survived into adulthood. Transgenic neonates that died showed vascular abnormalities of varying severity. Some exhibited bleeding into body cavities such as the pericardial space. Smaller localized hemorrhages were seen in many organs. Blood vessels were often dilated and thin-walled. To establish the development of these abnormalities, we examined mice at early (E10.5-14.5) and later (E15.5-17.5) developmental phases. Early events during vasculogenesis appear unaffected by Tie2-Grn as apparently normal primary vasculature had been established at E10.5. The earliest onset of vascular abnormality was at E15.5, with focal cerebral hemorrhage and enlarged vessels in various organs. Aberrant Tie2-Grn positive vessels showed thinning of the basement membrane and reduced investiture with mural cells. We conclude that progranulin promotes exaggerated vessel growth in vivo, with subsequent effects in

  7. Expression of the growth factor progranulin in endothelial cells influences growth and development of blood vessels: a novel mouse model.

    Directory of Open Access Journals (Sweden)

    Huishi Toh

    Full Text Available Progranulin is a secreted glycoprotein that regulates cell proliferation, migration and survival. It has roles in development, tumorigenesis, wound healing, neurodegeneration and inflammation. Endothelia in tumors, wounds and placenta express elevated levels of progranulin. In culture, progranulin activates endothelial proliferation and migration. This suggested that progranulin might regulate angiogenesis. It was, however, unclear how elevated endothelial progranulin levels influence vascular growth in vivo. To address this issue, we generated mice with progranulin expression targeted specifically to developing endothelial cells using a Tie2-promoter/enhancer construct. Three Tie2-Grn mouse lines were generated with varying Tie2-Grn copy number, and were called GrnLo, GrnMid, and GrnHi. All three lines showed increased mortality that correlates with Tie2-Grn copy number, with greatest mortality and lowest germline transmission in the GrnHi line. Death of the transgenic animals occurred around birth, and continued for three days after birth. Those that survived beyond day 3 survived into adulthood. Transgenic neonates that died showed vascular abnormalities of varying severity. Some exhibited bleeding into body cavities such as the pericardial space. Smaller localized hemorrhages were seen in many organs. Blood vessels were often dilated and thin-walled. To establish the development of these abnormalities, we examined mice at early (E10.5-14.5 and later (E15.5-17.5 developmental phases. Early events during vasculogenesis appear unaffected by Tie2-Grn as apparently normal primary vasculature had been established at E10.5. The earliest onset of vascular abnormality was at E15.5, with focal cerebral hemorrhage and enlarged vessels in various organs. Aberrant Tie2-Grn positive vessels showed thinning of the basement membrane and reduced investiture with mural cells. We conclude that progranulin promotes exaggerated vessel growth in vivo, with

  8. Planar cell polarity genes frizzled4 and frizzled6 exert patterning influence on arterial vessel morphogenesis

    Science.gov (United States)

    Gosak, Marko; Horvat, Denis; Žalik, Borut; Seguy, Benjamin; Chauvel, Remi; Malandain, Gregoire; Couffinhal, Thierry; Duplàa, Cécile; Marhl, Marko

    2017-01-01

    Quantitative analysis of the vascular network anatomy is critical for the understanding of the vasculature structure and function. In this study, we have combined microcomputed tomography (microCT) and computational analysis to provide quantitative three-dimensional geometrical and topological characterization of the normal kidney vasculature, and to investigate how 2 core genes of the Wnt/planar cell polarity, Frizzled4 and Frizzled6, affect vascular network morphogenesis. Experiments were performed on frizzled4 (Fzd4-/-) and frizzled6 (Fzd6-/-) deleted mice and littermate controls (WT) perfused with a contrast medium after euthanasia and exsanguination. The kidneys were scanned with a high-resolution (16 μm) microCT imaging system, followed by 3D reconstruction of the arterial vasculature. Computational treatment includes decomposition of 3D networks based on Diameter-Defined Strahler Order (DDSO). We have calculated quantitative (i) Global scale parameters, such as the volume of the vasculature and its fractal dimension (ii) Structural parameters depending on the DDSO hierarchical levels such as hierarchical ordering, diameter, length and branching angles of the vessel segments, and (iii) Functional parameters such as estimated resistance to blood flow alongside the vascular tree and average density of terminal arterioles. In normal kidneys, fractal dimension was 2.07±0.11 (n = 7), and was significantly lower in Fzd4-/- (1.71±0.04; n = 4), and Fzd6-/- (1.54±0.09; n = 3) kidneys. The DDSO number was 5 in WT and Fzd4-/-, and only 4 in Fzd6-/-. Scaling characteristics such as diameter and length of vessel segments were altered in mutants, whereas bifurcation angles were not different from WT. Fzd4 and Fzd6 deletion increased vessel resistance, calculated using the Hagen-Poiseuille equation, for each DDSO, and decreased the density and the homogeneity of the distal vessel segments. Our results show that our methodology is suitable for 3D quantitative

  9. Progress on Complications of Direct Bypass for Moyamoya Disease

    Science.gov (United States)

    Yu, Jinlu; Shi, Lei; Guo, Yunbao; Xu, Baofeng; Xu, Kan

    2016-01-01

    Moyamoya disease (MMD) involves progressive occlusion of the intracranial internal carotid artery resulting in formation of moyamoya-like vessels at the base of the brain. It can be characterized by hemorrhage or ischemia. Direct vascular bypass is the main and most effective treatment of MMD. However, patients with MMD differ from those with normal cerebral vessels. MMD patients have unstable intracranial artery hemodynamics and a poor blood flow reserve; therefore, during the direct bypass of superficial temporal artery (STA)-middle cerebral artery (MCA) anastomosis, perioperative risk factors and anesthesia can affect the hemodynamics of these patients. When brain tissue cannot tolerate a high blood flow rate, it becomes prone to hyperperfusion syndrome, which leads to neurological function defects and can even cause intracranial hemorrhage in severe cases. The brain tissue is prone to infarction when hemodynamic equilibrium is affected. In addition, bypass vessels become susceptible to occlusion or atrophy when blood resistance increases. Even compression of the temporalis affects bypass vessels. Because the STA is used in MMD surgery, the scalp becomes ischemic and is likely to develop necrosis and infection. These complications of MMD surgery are difficult to manage and are not well understood. To date, no systematic studies of the complications that occur after direct bypass in MMD have been performed, and reported complications are hidden among various case studies; therefore, this paper presents a review and summary of the literature in PubMed on the complications of direct bypass in MMD. PMID:27499690

  10. Progress on Complications of Direct Bypass for Moyamoya Disease.

    Science.gov (United States)

    Yu, Jinlu; Shi, Lei; Guo, Yunbao; Xu, Baofeng; Xu, Kan

    2016-01-01

    Moyamoya disease (MMD) involves progressive occlusion of the intracranial internal carotid artery resulting in formation of moyamoya-like vessels at the base of the brain. It can be characterized by hemorrhage or ischemia. Direct vascular bypass is the main and most effective treatment of MMD. However, patients with MMD differ from those with normal cerebral vessels. MMD patients have unstable intracranial artery hemodynamics and a poor blood flow reserve; therefore, during the direct bypass of superficial temporal artery (STA)-middle cerebral artery (MCA) anastomosis, perioperative risk factors and anesthesia can affect the hemodynamics of these patients. When brain tissue cannot tolerate a high blood flow rate, it becomes prone to hyperperfusion syndrome, which leads to neurological function defects and can even cause intracranial hemorrhage in severe cases. The brain tissue is prone to infarction when hemodynamic equilibrium is affected. In addition, bypass vessels become susceptible to occlusion or atrophy when blood resistance increases. Even compression of the temporalis affects bypass vessels. Because the STA is used in MMD surgery, the scalp becomes ischemic and is likely to develop necrosis and infection. These complications of MMD surgery are difficult to manage and are not well understood. To date, no systematic studies of the complications that occur after direct bypass in MMD have been performed, and reported complications are hidden among various case studies; therefore, this paper presents a review and summary of the literature in PubMed on the complications of direct bypass in MMD.

  11. Vessel Operating Units (Vessels)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — This data set contains data for vessels that are greater than five net tons and have a current US Coast Guard documentation number. Beginning in1979, the NMFS...

  12. Influence of preoperative serum N-terminal pro-brain type natriuretic peptide on the postoperative outcome and survival rates of coronary artery bypass patients

    Directory of Open Access Journals (Sweden)

    Thomas Schachner

    2010-01-01

    Full Text Available BACKGROUND: The N-terminal fragment of pro-brain type natriuretic peptide (NT-proBNP is an established biomarker for cardiac failure. OBJECTIVE: To determine the influence of preoperative serum NT-proBNP on postoperative outcome and mid-term survival in patients undergoing coronary artery bypass grafting (CABG. METHODS: In 819 patients undergoing isolated CABG surgery preoperative serum NT-proBNP levels were measured. NT-proBNP was correlated with various postoperative outcome parameters and survival rate after a median follow-up time of 18 (0.5-44 months. Risk factors of mortality were identified using χ2, Mann-Whitney test, and Cox regression. RESULTS: NT-proBNP levels >430 ng/ml and >502 ng/ml predicted hospital and overall mortality (p502 ng/ml (p=0.001. Age, preoperative serum creatinine, diabetes, chronic obstructive pulmonary disease, low left ventricular ejection fraction and BNP levels >502 ng/ml were isolated as risk factors for overall mortality. Multivariate Cox regression analysis, including the known factors influencing NT-proBNP levels, identified NT-proBNP as an independent risk factor for mortality (OR = 3.079 (CI = 1.149-8.247, p = 0.025. Preoperative NT-proBNP levels >502 ng/ml were associated with increased ventilation time (p=0.005, longer intensive care unit stay (p=0.001, higher incidence of postoperative hemofiltration (p=0.001, use of intra-aortic balloon pump (p502 ng/ml predict mid-term mortality after isolated CABG and are associated with significantly higher hospital mortality and perioperative complications.

  13. Flow characteristics in narrowed coronary bypass graft

    Science.gov (United States)

    Bernad, S. I.; Bosioc, A.; Bernad, E. S.; Petre, I.; Totorean, A. F.

    2016-06-01

    Tortuous saphenous vein graft (SVG) hemodynamics was investigated using computational fluid dynamics (CFD) techniques. Computed tomography (CT) technology is used for non-invasive bypass graft assessment 7 days after surgery. CT investigation shown two regions with severe shape remodelling first is an elbow type contortion and second is a severe curvature with tortuous area reduction. In conclusion, the helical flow induced by vessel torsion may stabilize the blood flow in the distal part of the SVG, reducing the flow disturbance and suppressing the flow separation, but in the distal end of the graft, promote the inflammatory processes in the vessels.

  14. Influence of structural parameters on the tendency of VVER-1000 reactor pressure vessel steel to temper embrittlement

    Science.gov (United States)

    Gurovich, B.; Kuleshova, E.; Zabusov, O.; Fedotova, S.; Frolov, A.; Saltykov, M.; Maltsev, D.

    2013-04-01

    In this paper the influence of structural parameters on the tendency of steels to reversible temper embrittlement was studied for assessment of performance properties of reactor pressure vessel steels with extended service life. It is shown that the growth of prior austenite grain size leads to an increase of the critical embrittlement temperature in the initial state. An embrittlement heat treatment at the temperature of maximum manifestation of temper embrittlement (480 °C) shifts critical embrittlement temperature to higher values due to the increase of the phosphorus concentration on grain boundaries. There is a correlation between phosphorus concentration on boundaries of primary austenite grains and the share of brittle intergranular fracture (that, in turn, depends on impact test temperature) in the fracture surfaces of the tested Charpy specimens.

  15. Flood Bypass Capacity Optimization

    Science.gov (United States)

    Siclari, A.; Hui, R.; Lund, J. R.

    2015-12-01

    Large river flows can damage adjacent flood-prone areas, by exceeding river channel and levee capacities. Particularly large floods are difficult to contain in leveed river banks alone. Flood bypasses often can efficiently reduce flood risks, where excess river flow is diverted over a weir to bypasses, that incur much less damage and cost. Additional benefits of bypasses include ecosystem protection, agriculture, groundwater recharge and recreation. Constructing or expanding an existing bypass costs in land purchase easements, and levee setbacks. Accounting for such benefits and costs, this study develops a simple mathematical model for optimizing flood bypass capacity using benefit-cost and risk analysis. Application to the Yolo Bypass, an existing bypass along the Sacramento River in California, estimates optimal capacity that economically reduces flood damage and increases various benefits, especially for agriculture. Land availability is likely to limit bypass expansion. Compensation for landowners could relax such limitations. Other economic values could affect the optimal results, which are shown by sensitivity analysis on major parameters. By including land geography into the model, location of promising capacity expansions can be identified.

  16. The in situ saphenous vein bypass graft: radiologic aspects.

    Science.gov (United States)

    Schwarz, W; Nozick, J; Richmand, D; Rodgers, B; Simpson, A; Argila, C; Honickman, S

    1986-03-01

    The use of the in situ saphenous vein for bypassing arterial occlusions in the lower extremities appears to have a higher patency rate than other bypass procedures but presents unique technical problems, such as lysing valves and occluding venous tributaries. Forty-four patients undergoing in situ bypasses had preoperative arteriograms. Special attention was paid to the small runoff vessels around the ankle, which are not suitable for reversed bypass procedures but may be adequate for in situ bypasses. Eight patients also had preoperative saphenous venograms, which revealed surgically important abnormalities in six cases. Postoperative arteriograms obtained within 2 weeks in 10 patients and within 2-12 months in 15 patients revealed persistent arteriovenous fistulas in four patients, stenoses in nine, occlusions in five, and progressive disease in the nonbypassed arteries in five patients. Early recognition of these problems led to 11 surgical repairs; nine repairs used the interventional radiologic procedures of balloon angioplasty, transcatheter embolization, and catheter thrombolysis. In this group of 44 patients, five patients died with patent bypasses and three patients required amputation despite functioning bypasses. Only four amputations were attributed to bypass failure. This low figure may be due to the close cooperation of the vascular surgeons and the vascular radiologists in dealing with these complicated cases.

  17. Innovations in Pedriatic Cradiopulmonary Bypass: a continuous process of quality improvement

    NARCIS (Netherlands)

    H.D. Golab (Hanna)

    2011-01-01

    textabstractCardiopulmonary bypass (CPB) is defined as a technique that temporarily replaces the function of the heart and lungs, maintaining an adequate blood circulation and oxygen content of the body during surgery of the heart and great vessels. The current practice of cardiopulmonary bypass was

  18. Extracranial–intracranial bypass for Takayasu’s arteritis: A case report

    Directory of Open Access Journals (Sweden)

    Richard M. Young, M.D.

    2014-12-01

    Conclusion: STA–MCA bypass to enhance cerebral blood flow in the setting of stroke symptoms due to Takayasu’s arteritis can serve as a bridge before definitive cardiothoracic treatment of the great vessels.

  19. The influence of nutrients, biliary-pancreatic secretions, and systemic trophic hormones on intestinal adaptation in a Roux-en-Y bypass model

    DEFF Research Database (Denmark)

    Taqi, Esmaeel; Wallace, Laurie E; de Heuvel, Elaine

    2010-01-01

    The signals that govern the upregulation of nutrient absorption (adaptation) after intestinal resection are not well understood. A Gastric Roux-en-Y bypass (GRYB) model was used to isolate the relative contributions of direct mucosal stimulation by nutrients, biliary-pancreatic secretions...

  20. Computed tomography perfusion evaluation after extracranial-intracranial bypass surgery

    NARCIS (Netherlands)

    Vos, P.C.; Riordan, A.J.; Smit, E.J.; Jong, H.W. de; Zwan, A. van der; Velthuis, B.K.; Viergever, M.A.; Dankbaar, J.W.

    2015-01-01

    OBJECTIVE: Perfusion imaging is increasingly used for postoperative evaluation of extracranial to intracranial (EC-IC) bypass surgery. Altered hemodynamics and delayed arrival of the contrast agent in the area fed by the bypass can influence perfusion measurement. We compared perfusion asymmetry obt

  1. Computed tomography perfusion evaluation after extracranial-intracranial bypass surgery

    NARCIS (Netherlands)

    Vos, Pieter C.; Riordan, Alan J.; Smit, Ewoud J.; de Jong, Hugo W. A. M.; van der Zwan, Albert; Velthuis, BK; Viergever, Max A.; Dankbaar, Jan Willem

    2015-01-01

    Objective: Perfusion imaging is increasingly used for postoperative evaluation of extracranial to intracranial (EC-IC) bypass surgery. Altered hemodynamics and delayed arrival of the contrast agent in the area fed by the bypass can influence perfusion measurement. We compared perfusion asymmetry obt

  2. Bypassing damaged nervous tissue

    CERN Document Server

    Shneider, M N

    2016-01-01

    We show the principal ability of bypassing damaged demyelinated portions of nervous tissue, thereby restoring its normal function for the passage of action potentials. We carry out a theoretical analysis on the basis of the synchronization mechanism of action potential propagation along a bundle of neurons, proposed recently in [1]. And we discuss the feasibility of implement a bypass to restore damaged nervous tissue and creating an artificial neuron network.

  3. Robotically-Assisted Coronary Artery Bypass Grafting

    Directory of Open Access Journals (Sweden)

    Thierry A. Folliguet

    2010-01-01

    Full Text Available Objectives. Robotic surgery enables to perform coronary surgery totally endoscopically. This report describes our experience using the da Vinci system for coronary artery bypass surgery. Methods. Patients requiring single-or-double vessel revascularization were eligible. The procedure was performed without cardiopulmonary bypass on a beating heart. Results. From April 2004 to May 2008, fifty-six patients were enrolled in the study. Twenty-four patients underwent robotic harvesting of the mammary conduit followed by minimal invasive direct coronary artery bypass (MIDCAB, and twenty-three patients had a totally endoscopic coronary artery bypass (TECAB grafting. Nine patients (16% were converted to open techniques. The mean total operating time for TECAB was 372±104 minutes and for MIDCAB was 220±69 minutes. Followup was complete for all patients up to one year. There was one hospital death following MIDCAB and two deaths at follow up. Forty-eight patients had an angiogram or CT scan revealing occlusion or anastomotic stenoses (>50% in 6 patients. Overall permeability was 92%. Conclusions. Robotic surgery can be performed with promising results.

  4. Your diet after gastric bypass surgery

    Science.gov (United States)

    Gastric bypass surgery - your diet; Obesity - diet after bypass; Weight loss - diet after bypass ... You had gastric bypass surgery. This surgery made your stomach smaller by closing off most of your stomach with staples. It changed the way your ...

  5. Bypass Flow Study

    Energy Technology Data Exchange (ETDEWEB)

    Richard Schultz

    2011-09-01

    The purpose of the fluid dynamics experiments in the MIR (Matched Index of-Refraction) flow system at Idaho National Laboratory (INL) is to develop benchmark databases for the assessment of Computational Fluid Dynamics (CFD) solutions of the momentum equations, scalar mixing, and turbulence models for the flow ratios between coolant channels and bypass gaps in the interstitial regions of typical prismatic standard fuel element (SFE) or upper reflector block geometries of typical Modular High-temperature Gas-cooled Reactors (MHTGR) in the limiting case of negligible buoyancy and constant fluid properties. The experiments use Particle Image Velocimetry (PIV) to measure the velocity fields that will populate the bypass flow study database.

  6. Heart bypass surgery - minimally invasive

    Science.gov (United States)

    ... Names Minimally invasive direct coronary artery bypass; MIDCAB; Robot-assisted coronary artery bypass; RACAB; Keyhole heart surgery; ... M. is also a founding member of Hi-Ethics and subscribes to the principles of the Health ...

  7. STARDUST experimental campaign and numerical simulations: influence of obstacles and temperature on dust resuspension in a vacuum vessel under LOVA

    Science.gov (United States)

    Bellecci, C.; Gaudio, P.; Lupelli, I.; Malizia, A.; Porfiri, M. T.; Quaranta, R.; Richetta, M.

    2011-05-01

    Activated dust mobilization during a Loss of Vacuum Accident (LOVA) is one of the safety concerns for the International Thermonuclear Experimental Reactor (ITER). Intense thermal loads in fusion devices occur during plasma disruptions, edge localized modes and vertical displacement events. They will result in macroscopic erosion of the plasma facing materials and consequent accumulation of activated dust into the ITER vacuum vessel (VV). These kinds of events can cause dust leakage outside the VV that represents a high radiological risk for the workers and the population. A small facility, Small Tank for Aerosol Removal and Dust (STARDUST), was set up at the ENEA Frascati laboratories to perform experiments concerning the dust mobilization in a volume with the initial conditions similar to those existing in ITER VV. The aim of this work was to reproduce a low pressurization rate (300 Pa s-1) LOVA event in a VV due to a small air leakage for two different positions of the leak, at the equatorial port level and at the divertor port level, in order to evaluate the influence of obstacles and walls temperature on dust resuspension during both maintenance (MC) and accident conditions (AC) (Twalls = 25 °C MC, 110 °C AC). The dusts used were tungsten (W), stainless steel 316 (SS316) and carbon (C), similar to those produced inside the vacuum chamber in a fusion reactor when the plasma facing materials vaporize due to the high energy deposition. The experimental campaign has been carried out by introducing inside STARDUST facility an obstacle to simulate the presence of objects, such as divertor. In the obstacle a slit was cut to simulate the limiter-divertor gap inside ITER VV. In this paper experimental campaign results are shown in order to investigate how the divertor and limiter-divertor gap influence dust mobilization into a VV. A two-dimensional (2D) modelling of STARDUST was made using the CFD commercial code FLUENT, in order to get a preliminary overview of the

  8. The Best Bypass Surgery Trial

    DEFF Research Database (Denmark)

    Møller, Christian H; Jensen, Birte Østergaard; Gluud, Christian

    2007-01-01

    Recent trials suggest that off-pump coronary artery bypass grafting (OPCAB) reduces the risk of mortality and morbidity compared with conventional coronary artery bypass grafting (CCAB) using cardiopulmonary bypass. Patients with a moderate- to high-risk of complications after CCAB may have addit...

  9. Partial Ileal Bypass Undone

    NARCIS (Netherlands)

    Beynen, A.C.; Schouten, J.A.; Hoitsma, H.F.W.

    1984-01-01

    Partial ileal bypass (PIB) for the treatment of hypercholesterolaemia was introduced 20 years ago. About 110 cases have been described. We know of only 1 case of restoration of intestinal continuity; no details were given. We report here the second case of PIB in the Netherlands; the operation was r

  10. Aortic valve bypass

    DEFF Research Database (Denmark)

    Lund, Jens T; Jensen, Maiken Brit; Arendrup, Henrik;

    2013-01-01

    In aortic valve bypass (AVB) a valve-containing conduit is connecting the apex of the left ventricle to the descending aorta. Candidates are patients with symptomatic aortic valve stenosis rejected for conventional aortic valve replacement (AVR) or transcatheter aortic valve implantation (TAVI...

  11. Experimental laparoscopic aortobifemoral bypass.

    Science.gov (United States)

    Dion, Y M; Chin, A K; Thompson, T A

    1995-08-01

    The goal of the present study is to develop a technique for laparoscopic aortobifemoral bypass. Piglets weighing between 60 and 78 kg were anesthetized with halothane. The lateral retroperitoneal approach was preferred to the more familiar anterior transperitoneal approach and was successfully completed in 19 piglets. The piglets were placed in the right lateral decubitus position. The first port (2 cm) was inserted halfway between the tip of the 12th rib and the iliac crest. Four other trocars were placed in the retroperitoneum after balloon inflation had allowed creation of a space which permitted visualization of the aorta from the left renal artery down to the aorto-iliac junction. After evacuation of the retropneumoperitoneum, the cavity was maintained using an abdominal lift device and a retractor. Using this approach, we performed four aorto-bifemoral bypasses (end-to-end aortic anastomosis) after conventional intravenous heparinization (100 IU/kg) in less than 4 h. Blood loss did not exceed 250 ml and the hematocrit remained stable. Postmortem evaluation of the grafts revealed they were positioned as in a conventional bypass, their limbs having followed in the created retroperitoneal tunnels along the path of the native arteries. No mortality occurred before sacrifice of the animals. We believe that this first performed series of totally retroperitoneal laparoscopic aortobifemoral bypasses in the porcine model is useful in preparation for human application due to the anatomical similarities in the periaortic region.

  12. The influence of vessel movements on the energy expenditure of fishermen in relation to activities and occupational tasks on board

    DEFF Research Database (Denmark)

    Breidahl, Tomas; Christensen, Michael; Jepsen, Jørgen Riis;

    2015-01-01

    recorded their work activities on an hourly basis during a 4 days fishing voyage. The energy expenditure was estimated with a body monitoring system (SenseWear Pro 3) carried as an armband, placed on the right upper arm. The vessels' movements were assessed by a gyroscope placed in the wheelhouse...

  13. The influence of improved gastric bypass on resistin of GK rats%改良胃旁路术对GK大鼠抵抗素的影响

    Institute of Scientific and Technical Information of China (English)

    翁山耕; 徐常国; 吴书清; 张斌

    2012-01-01

    目的:探讨改良胃旁路手术(improved gastric bypass)对2型糖尿病GK大鼠(Goto-Kakizaki rats)的降糖作用及其机制.方法:20只雄性GK大鼠随机分为手术组和对照组,每组10只.对手术组大鼠行改良胃旁路术,对照组大鼠在十二指肠球部远端0.5 cm处切断吻合.检测术前1周及术后第8周两组GK大鼠体重、空腹血糖(FPG)、血脂、血浆胰岛素、血浆抵抗素水平.结果:术后8周,手术组大鼠FPG由术前的(5.2±0.3)mmol/L降至(4.0±0.2)mmol/L,血浆抵抗素由术前的(9.9±1.7)mmol/L降至(5.7±1.0)mmol/L,与术前相比,差异均有统计学意义(P<0.05).结论:改良胃旁路术能降低GK大鼠的血糖,并且能够降低GK大鼠的血脂和血浆抵抗素,其可能是胃旁路术治疗2型糖尿病的机制之一.%Objective To study the antidiabetic effects and the mechanisms of improved gastric bypass (GBP) in Goto-Kakizaki (GK) rats with type 2 diabetes. Methods Twenty male GK rats were randomized into two groups; operation group and control group. Operation group underwent improved gastric bypass, while control group underwent sham operation. Body weight, fasting plasma glouse (FPG) , blood lipid, plasma insuline and plasma resistin of two groups were detected one week before surgery and eight weeks after surgery, respectively. Results No differences were found in body weight between operation group and control group in the same week. But eight weeks after surgery, the average level of fasting plasma glucose was decreased from (5.2 ?0.3) mmol/L to (4.0 ?0.2) mmol/L and the average level of plasma resistin was decreased from (9.9 ?1.7) mmol/L to (5.7 ?1.0) mmol/L in operation group, which were significantly lower than that of control group. Conclusions The improved gastric bypass not only can significantly decrease blood glucose of GK rats, but it also can decrease the blood lipid and plasma resistin of GK rats, which may be one of mechanisms of surgical treatment of type 2 diabetes.

  14. Relationship of femorodistal bypass patency to clinical outcome. Iloprost Bypass International Study Group

    DEFF Research Database (Denmark)

    Watson, H R; Schroeder, T V; Simms, M H;

    1999-01-01

    To investigate the relationship between bypass patency, limb survival and clinical symptoms after femorodistal bypass procedures.......To investigate the relationship between bypass patency, limb survival and clinical symptoms after femorodistal bypass procedures....

  15. Coronary Artery Bypass

    Directory of Open Access Journals (Sweden)

    Kadri Ceberut

    2011-01-01

    Full Text Available Ancient schwannoma is a rare variant of neural tumors though rarely seen in the thorax. The combination with coronary artery diseases is also rare. Here we describe a 66 year-old male who had undergone one-stage combined surgery for thoracic ancient schwannomas removal and coronary artery disease. The masses were, respectively, 13 cm in the middle mediastinum and 5 cm in diameter originating from the intercostal nerve. The tumors were successfully removed using sternotomy, and then a coronary artery bypass grafting was performed. Here we discuss this rare tumor in relation to the relevant literature.

  16. About a mechanism of the influence of shear stress for viscosity of the blood in vessels of small diameter

    Directory of Open Access Journals (Sweden)

    Лев Николаевич Катюхин

    2014-12-01

    Full Text Available It is proposed a physiological and experimentally confirmed explanation of Fåhraeus-Lindqvist-effect in capillaries using the profile analyses of osmotic deformability of red blood cells. It was shown the dose-dependent change of the erythrocytes deformability in the stage of isotropic spheres after forming artificial water pores (nystatin and occlusion (PbCl2 of available pores. The Sigma-effect reducing of hematocrit and viscosity in a shear flow of blood through the vessels of a small diameter was conditioned by the interchange of liquid phase between the erythrocyte and the plasma.

  17. Spiritual Bypass: A Preliminary Investigation

    Science.gov (United States)

    Cashwell, Craig S.; Glosoff, Harriet L.; Hammond, Cheree

    2010-01-01

    The phenomenon of spiritual bypass has received limited attention in the transpersonal psychology and counseling literature and has not been subjected to empirical inquiry. This study examines the phenomenon of spiritual bypass by considering how spirituality, mindfulness, alexithymia (emotional restrictiveness), and narcissism work together to…

  18. Influence of preoperative coronary collateral circulation on in-hospital mortality in patients undergoing coronary artery bypass graft surgery with intra-aortic balloon pump support

    Institute of Scientific and Technical Information of China (English)

    Hasan Gungor; Cemil Zencir; Abraham Samuel Babu; Cagdas Akgullu; Ufuk Eryilmaz; Ali Zorlu; Mithat Selvi

    2014-01-01

    Background Outcomes in patients requiring coronary artery bypass graft (CABG) surgery have been improved with devices such as the intra-aortic balloon pump (IABP).Good coronary collateral circulation (CCC) has been shown to reduce mortality in patients with coronary artery disease (CAD).We aimed to investigate whether poor preoperative CCC grade is a predictor of in-hospital mortality in CABG surgery requiring IABP support.Methods Fifty-five consecutive patients who were undergoing isolated first time on-pump CABG surgery with IABP support were enrolled into this study and CCC of those patients was evaluated.Results Twenty-seven patients had poor CCC and 28 patients had good CCC.In-hospital mortality rate in poor CCC group was significantly higher than good CCC group (14 (50%) vs.4 (13%),P=0.013).Preoperative hemoglobin level (OR:0.752; 95% CI,0.571-0.991,P=0.043),chronic obstructive pulmonary disease (OR:6.731; 95% CI,1.159-39.085,P=0.034) and poor CCC grade (OR:5.750; 95% CI,1.575-20.986,P=0.008) were associated with post-CABG in-hospital mortality.Poor CCC grade (OR:4.853; 95% CI,1.124-20.952,P=0.034) and preoperative hemoglobin level (OR:0.624; 95% CI,0.476-0.954,P=0.026) were independent predictors of in-hospital mortality after CABG.Conclusion Preoperative poor CCC and hemoglobin are predictors of in-hospital mortality after CABG with IABP support.

  19. The Primary Study of the Construction of Small Diameter Tissue-engineered Blood Vessel

    Institute of Scientific and Technical Information of China (English)

    2005-01-01

    1 IntroductionToday, the blood vessel substitutes are in large demand for coronary and peripheral bypass procedures. Each year, more than 600,000 coronary artery bypass graft procedures are performed in the United States. There are some blood vessel substitutes including autografts, allografts and synthetic grafts that have been applied in vascular surgery in clinics. But their clinical implementations are prevented, especially for the <6mm in diameter grafts, because of their shortcomings such as inadequat...

  20. Current status of coronary artery bypass surgery

    Institute of Scientific and Technical Information of China (English)

    CHEN Xin

    2009-01-01

    @@ Surgical revascularization for atherosclerotic heart disease, also called coronary artery bypass grafting (CABG), was first performed in 1962, and is one of the great achievements in medicine. Relief of angina, improvement of exercise tolerance, and the realization of survival benefit have been documented.1 CABG has been used in multi-vessel disease and left main stenosis for over 40 years.2 In the last two decades the mortality of CABG has decreased to less than 2% despite an aging population with increased risk factors. However, percutaneous coronary intervention (PCI), especially with drug-eluting stents, has been challenging CABG, While PCI has improved, CABG has also progressed with better peri-operative management, a higher use of arterial grafting, off-pump surgery, and improved techniques with minimally invasive surgical options.3,4

  1. Short and long term mortality after coronary artery bypass grafting (CABG is influenced by socioeconomic position but not by migration status in Sweden, 1995-2007.

    Directory of Open Access Journals (Sweden)

    Dashti Ali M Dzayee

    Full Text Available BACKGROUND: There are no nationwide studies on mortality after coronary artery bypass grafting (CABG among foreign-born populations that include detailed information about country of birth and information about socioeconomic position. The objective was to investigate the risk of mortality after CABG considering socioeconomic position, sex and country of birth. MATERIAL AND METHODS: We included all 72 333 patients undergoing a first isolated CABG in Sweden, during 1995 - 2007 of whom 12.7% were foreign-born. The patients were classified according to educational level, sex, and country of birth and were followed up to December 2007. We estimated the risk of short and long term mortality after CABG in a multivariable model adjusted for age, calendar year of surgery, diabetes, educational level, and waiting time for surgery. Hazard ratios (HR with 95% confidence intervals (CI were calculated based on the Cox proportional hazard model. FINDINGS: There were 15,284 deaths during the follow-up, 10.4% of whom were foreign-born. The foreign-born patients were 3 to 4 years younger than Sweden-born patients at the time of CABG surgery. There were no significant differences in overall early or late mortality between foreign-born and Sweden-born men and women after CABG. All-cause mortality differed in between regions and was highest in foreign-born men from Eastern Africa (HR 3.80, 95% CI 1.58-9.17, China (HR 3.61, 95% CI 1.50-8.69, and in Chile (HR 2.12, 95% CI 1.01-4.47. Patients with low level of education had worse survival compared to those with longer than 12 years of education irrespective of sex and country of birth. This difference was more pronounced among foreign-born women (HR 1.50, 95% CI 1.00-2.33. CONCLUSION: This national study showed higher CABG mortality in patients from lower socioeconomic position. Early and late mortality did not differ after isolated CABG in foreign-born and Sweden-born patients.

  2. Cardiopulmonary bypass in pregnancy

    Directory of Open Access Journals (Sweden)

    Mukul Chandra Kapoor

    2014-01-01

    Full Text Available Cardiac surgery carried out on cardiopulmonary bypass (CPB in a pregnant woman is associated with poor neonatal outcomes although maternal outcomes are similar to cardiac surgery in non-pregnant women. Most adverse maternal and fetal outcomes from cardiac surgery during pregnancy are attributed to effects of CPB. The CPB is associated with utero-placental hypoperfusion due to a number of factors, which may translate into low fetal cardiac output, hypoxia and even death. Better maternal and fetal outcomes may be achieved by early pre-operative optimization of maternal cardiovascular status, use of perioperative fetal monitoring, optimization of CPB, delivery of a viable fetus before the operation and scheduling cardiac surgery on an elective basis during the second trimester.

  3. Does heparin pretreatment affect the haemostatic system during and after cardiopulmonary bypass?

    NARCIS (Netherlands)

    Brinks, H.J.; Weerwind, P.W.; Bogdan, S.; Verbruggen, H.W.; Brouwer, M.H.J.

    2001-01-01

    In this clinical pilot study, the influence of heparin pretreatment on the haemostatic system during and after cardiopulmonary bypass (CPB) was investigated. Thirteen patients scheduled for elective coronary artery bypass grafting (CABG) were divided into two groups: heparin pretreated (HP, n = 6) a

  4. Reactor vessel

    OpenAIRE

    Makkee, M.; Kapteijn, F.; Moulijn, J.A

    1999-01-01

    A reactor vessel (1) comprises a reactor body (2) through which channels (3) are provided whose surface comprises longitudinal inwardly directed parts (4) and is provided with a catalyst (6), as well as buffer bodies (8, 12) connected to the channels (3) on both sides of the reactor body (2) and comprising connections for supplying (9, 10, 11) and discharging (13, 14, 15) via the channels (3) gases and/or liquids entering into a reaction with each other and substances formed upon this reactio...

  5. Influence of gastric bypass on expressions of insulin receptor and insulin receptor substrate 2 in islet cells of rats with type 2 diabetes mellitus%胃转流术对2型糖尿病大鼠胰岛细胞胰岛素受体及胰岛素受体底物2表达的影响

    Institute of Scientific and Technical Information of China (English)

    石力; 文艺; 张少华; 陈涛; 崔剑锋; 闫洪涛; 汤礼军

    2015-01-01

      结论:2型糖尿病大鼠胰岛细胞中IRc及IRS-2表达下调,而胃转流术能够使其表达显著增加,这可能是该手术产生对2型糖尿病产生疗效的机制之一。%Objective:To investigate the influence of gastric bypass surgery on expressions of insulin receptor (IRc) and insulin receptor substrate 2 (IRS-2) in islet cells of rats with type 2 diabetes mellitus. Methods:The model of type 2 diabetes mellitus in rats was induced by a high fat and high glucose diet plus intraperitoneal streptozotocin injection, and then the rats with establishment of successful model were divided into model group and gastric bypass group, using the normal rats as normal control group. The rats in gastric bypass group underwent gastrojejunostomy and side-to-side jejunojejunostomy, and those in model group and normal control group underwent sham operation. The fasting glucose and serum insulin levels were measured and insulin sensitivity index (ISI) was calculated before and at 8 weeks atfer operation, and the IRc and IRS-2 expressions in pancreatic tissues were determined by immunohistochemical staining. Results:hTe fasting glucose levels were increased and ISI values were decreased signiifcantly in both model group and gastric bypass group compared with normal control group before operation, but these two parameters were signiifcantly improved in gastric bypass group compared with model group atfer operation (all P0.05). In gastric bypass group at 8 weeks atfer operation, both IRc and IRS-2 expression levels were signiifcantly higher than those in model group (both P0.05). Conclusion:IRc and IRS-2 expressions are decreased in islet cells of rats with type 2 diabetes mellitus, and gastric bypass surgery can increase IRc and IRS-2 expression, which may be one of the mechanisms for the therapeutic effect of this surgical procedure on type 2 diabetes mellitus.

  6. The use of a Perma-Flow graft for coronary artery bypass surgery.

    Science.gov (United States)

    Schmid, C; Weyand, M; Kerber, S; Breithardt, G; Scheld, H H

    1996-01-01

    We report on our first clinical use of a Perma-Flow graft for coronary artery bypass surgery (CABG). It may well be that repeated successful use of this graft will offer a chance for revascularization to patients who might otherwise have been denied for lack of appropriate vessels.

  7. Axillobifemoral bypass: a brief surgical and historical review

    Science.gov (United States)

    Mishall, Priti L.; Matakas, Jason D.; English, Keara; Allyn, Katherine; Algava, Diane; Howe, Ruth A.; Downie, Sherry A.

    2017-01-01

    Peripheral artery disease (PAD) occurs when plaque accumulates in the arterial system and obstructs blood flow. Narrowing of the abdominal aorta and the common iliac arteries due to atherosclerotic plaques restricts blood supply to the lower limbs. Clinically, the lower limb symptoms of PAD are intermittent claudication, discoloration of the toes, and skin ulcers, all due to arterial insufficiency. Surgical revascularization is the primary mode of treatment for patients with severe limb ischemia. The objective of the surgical procedure is to bypass a blockage in an occluded major vessel by constructing an alternate route for blood flow using an artificial graft. This article presents information on aortoiliac reconstruction, with an emphasis on axillobifemoral bypass grafting.

  8. Bypass rewiring and robustness of complex networks

    Science.gov (United States)

    Park, Junsang; Hahn, Sang Geun

    2016-08-01

    A concept of bypass rewiring is introduced, and random bypass rewiring is analytically and numerically investigated with simulations. Our results show that bypass rewiring makes networks robust against removal of nodes including random failures and attacks. In particular, random bypass rewiring connects all nodes except the removed nodes on an even degree infinite network and makes the percolation threshold 0 for arbitrary occupation probabilities. In our example, the even degree network is more robust than the original network with random bypass rewiring, while the original network is more robust than the even degree networks without random bypass. We propose a greedy bypass rewiring algorithm which guarantees the maximum size of the largest component at each step, assuming which node will be removed next is unknown. The simulation result shows that the greedy bypass rewiring algorithm improves the robustness of the autonomous system of the Internet under attacks more than random bypass rewiring.

  9. Bypass Rewiring and Robustness of Complex Networks

    CERN Document Server

    Park, Junsang

    2016-01-01

    A concept of bypass rewiring is introduced and random bypass rewiring is analytically and numerically investigated with simulations. Our results show that bypass rewiring makes networks robust against removal of nodes including random failures and attacks. Especially, random bypass rewiring connects all nodes except the removed nodes on an even degree infinite network and makes the percolation threshold $0$ for arbitrary occupation probabilities. In our example, the even degree network is more robust than the original network with random bypass rewiring while the original network is more robust than the even degree networks without random bypass. We propose a greedy bypass rewiring algorithm which guarantees the maximum size of the largest component at each step, assuming which node will be removed next is unknown. The simulation result shows that the greedy bypass rewiring algorithm improves the robustness of the autonomous system of the Internet under attacks more than random bypass rewiring.

  10. Clinical factors influencing surgical approach selection of robotic-enhanced minimally invasive coronary artery bypass grafting%机器人冠状动脉旁路移植术微创术式选择影响因素研究

    Institute of Scientific and Technical Information of China (English)

    成楠; 高长青; 杨明; 吴扬

    2013-01-01

    Objective To investigate clinical factors that influence the selection of minimally approach between minimally invasive direct coronary artery bypass (MIDCAB) and totally endoscopic coronary artery bypass (TECAB).Methods From February 2007 to January 2013,patients were selected under uniform criteria.A total of 202 patients including 142 male and 60 female patients with age range from 33 to 80 years and average age of (59 ± 10) years were included and were all routinely prepared for TECAB.Either TECAB or MIDCAB was performed based on the intraoperative condition.There were 90 patients who underwent TECAB (TECAB group) and 112 patients who received MIDCAB surgery (MIDCAB group).Univariate analysis was used to compare preoperative,intraoperative and early postoperative parameters.Logistic multivariate regression analysis was used to discuss independent influencing factors of minimally invasive approach selection.Results All of the patients successfully received TECAB or MIDCAB surgery without mortality,severe complications or conversion to sternotomy.The early and midterm follow up of graft patency (by computed tomography angiography) was satisfactory.The mean operative time was (160 ±64) minutes,mean graft flow was (27 ± 18) ml/min.Univariate analysis showed that sex ratio (3.5 vs.1.8,t=4.350,P=0.037),weight [(69 ±11)kgvs.(72±11)kg,t =-1.979,P=0.049],multivessel coronary disease (43.3% vs.60.7%,t =6.051,P =0.014),and learning curve case (4.4% vs.14.3%,t =5.418,P =0.02) were significant predictors of conversion to MIDCAB.By multivariate analysis,multivessel coronary disease (HR =1.964,95% CI:1.049-3.680,P =0.035) and learning curve case (HR =4.538,95% CI:1.219-16.891,P =0.024) were independent influencing factors of MIDCAB approach.Conclusions Robotic-assisted minimally invasive coronary artery bypass grafting can be performed safely and effectively either by TECAB or MIDCAB.Multivessel coronary disease and early learning curve cases are independent

  11. Interpositional carotid artery bypass strategies in the surgical management of aneurysms and tumors of the skull base.

    Science.gov (United States)

    Liu, James K; Couldwell, William T

    2003-03-15

    Cerebral revascularization is an important component in the surgical management of complex skull base tumors and aneurysms. Patients who harbor complex aneurysms that cannot be clipped directly and in whom parent vessel occlusion cannot be tolerated may require cerebrovascular bypass surgery. In cases in which skull base tumors encase the carotid artery (CA) and a resection is desired, a cerebrovascular bypass may be necessary in planned CA occlusion or sacrifice. In this review the authors discuss options for performing high-flow anterograde interposition CA bypass for lesions of the skull base. The authors review three important bypass techniques involving saphenous vein grafts: the cervical-to-petrous internal carotid artery (ICA), petrous-to-supraclinoid ICA, and cervical-to-supraclinoid ICA bypass. These revascularization techniques are important tools in the surgical treatment of complex aneurysms and tumors of the skull base and cavernous sinus.

  12. Dissolution vessel

    Energy Technology Data Exchange (ETDEWEB)

    Natsume, Tomohiro; Fujioka, Tsunaaki

    1998-05-22

    A basket for containing sheared fuel pieces of spent fuel assemblies in a dissolving vessel main body has many apertures for keeping the concentration of a dissolving liquid at the inner side and the outer side of the basket uniformly. Secured neutron absorbers such as boron stainless and hafnium are appended to one or both surfaces of the basket. Partitioning members are disposed in the basket, and the partitioning members are formed in a lattice-like shape. The partitioning members are also made of secured neutron absorbers such as boron stainless and hafnium. The inside dimension of each division (lattice distance) is determined to about 15cm. Then, it is no more necessary to add soluble neutron absorbers such as gadolinium nitrate to a dissolution solution such as nitric acid thereby enabling to reduce the amount of radioactive wastes. (I.N.)

  13. Computer-assisted LAD bypass grafting at the open heart

    Science.gov (United States)

    Hartung, Christine; Gnahm, Claudia; Friedl, Reinhard; Hoffmann, Martin; Dietmayer, Klaus

    2009-02-01

    Open heart bypass surgery is the standard treatment in advanced coronary heart diseases. For an effective revascularization procedure, optimal placement of the bypass is very important. To accelerate the intraoperative localization of the anastomosis site and to increase the precision of the procedure, a concept for computer assistance in open heart bypass surgery has been developed comprising the following steps: 1. Preprocedural planning: A patient-specific coronary map with information on vessel paths and wall plaque formations is extracted from a multi-slice computed tomography (MSCT). On this basis, the heart surgeon and the cardiac radiologist define the optimal anastomosis site prior to surgery. 2. Intraoperative navigation: During surgery, data are recorded at the beating heart using a stereo camera system. After registering the pre- and intraoperative data sets, preprocedural information can be transferred to the surgical site by overlaying the coronary map and the planned anastomosis site on the live video stream. With this visual guidance system, the surgeon can navigate to the planned anastomosis site. In this work, the proposed surgical assistance system has been validated for the left anterior descending coronary artery (LAD). The accuracy of the registration mechanism has been evaluated in retrospective on patient data sets and the effects of breathing motion were quantified. The promising results of the retrospective evaluation led to the in-vivo application of the computer assistance system during several bypass grafting procedures. Intraoperative navigation has been performed successfully and postoperative evaluation confirms that the bypass grafts were accurately positioned to the preoperatively planned anastomosis sites.

  14. [Prevalence and influence of risk factors on coronary shunting operations in patients with aterosclerosis of abdominal aorta and peripheral vessels].

    Science.gov (United States)

    Konstantinov, B A; Bazylev, V V; Belov, Iu V; Kizyma, A G

    2008-01-01

    Retrospective study analysis concerning the prevalence of risk factors for unfavorable outcomes after coronary operations in patients with peripheral arterial atherosclerosis is presented. Meta-analysis of individual risk factors was carried out. Frequency of complications after coronary shunting in patients with various concomitant diseases is evaluated. The multifactorial relative risk affecting hospital lethality is defined. The study includes 131 patients with generalized atherosclerosis, which have underwent myocardial revascularization at the first stage (the main group) and at the second stage have been operated on abdominal aorta and peripheral arteries. 1128 patients without peripheral arterial atherosclerosis have made the control group. They underwent only coronary shunting. All patients were treated from December of 1994 till June of 2006. Relying on the results of the study cumulative relative risk for unfavorable outcomes after revascularization is 1.8 times higher in patients from the main group than in patients from the control group, and the risk for primary complications is 2.03 times higher. Concomitant atherosclerotic arterial involvement among cardiosurgical patients is associated with high risk for stroke in postoperative period. In case of chronic renal failure risk factors are cumulated. In the main group lethality made 5% , which was higher as compared with the control group. Correlation of such risk factors as heart failure and renal failure (creatinine level more than 1.8 mg/dl) with lethality has been revealed among patients from the main group. Lethality risk raises in 5.30 times in the presence of heart failure in medical history, and raises in 13.15 times in case of initially elevated creatinine level. Age of patient didn't have any influence on lethality in early postoperative period.

  15. Impact of Intraoperative Events on Cerebral Tissue Oximetry in Patients Undergoing Cardiopulmonary Bypass

    NARCIS (Netherlands)

    Severdija, E.E.; Vranken, N.P.; Teerenstra, S.; Ganushchak, Y.M.; Weerwind, P.W.

    2015-01-01

    Previous studies showed that decreased cerebral saturation during cardiac surgery is related to adverse postoperative outcome. Therefore, we investigated the influence of intraoperative events on cerebral tissue saturation in patients undergoing cardiac surgery with cardiopulmonary bypass (CPB). A t

  16. In Vivo Clearance of Alpha-1 Acid Glycoprotein Is Influenced by the Extent of Its N-Linked Glycosylation and by Its Interaction with the Vessel Wall

    Directory of Open Access Journals (Sweden)

    Teresa R. McCurdy

    2012-01-01

    Full Text Available Alpha-1 acid glycoprotein (AGP is a highly glycosylated plasma protein that exerts vasoprotective effects. We hypothesized that AGP’s N-linked glycans govern its rate of clearance from the circulation, and followed the disappearance of different forms of radiolabeled human AGP from the plasma of rabbits and mice. Enzymatic deglycosylation of human plasma-derived AGP (pdAGP by Peptide: N-Glycosidase F yielded a mixture of differentially deglycosylated forms (PNGase-AGP, while the introduction of five Asn to Gln mutations in recombinant Pichia pastoris-derived AGP (rAGP-N(5Q eliminated N-linked glycosylation. PNGase-AGP was cleared from the rabbit circulation 9-fold, and rAGP-N(5Q, 46-fold more rapidly than pdAGP, primarily via a renal route. Pichia pastoris-derived wild-type rAGP differed from pdAGP in expressing mannose-terminated glycans, and, like neuraminidase-treated pdAGP, was more rapidly removed from the rabbit circulation than rAGP-N(5Q. Systemic hyaluronidase treatment of mice transiently decreased pdAGP clearance. AGP administration to mice reduced vascular binding of hyaluronic acid binding protein in the liver microcirculation and increased its plasma levels. Our results support a critical role of N-linked glycosylation of AGP in regulating its in vivo clearance and an influence of a hyaluronidase-sensitive component of the vessel wall on its transendothelial passage.

  17. Influence of Modelling Options in RELAP5/SCDAPSIM and MAAP4 Computer Codes on Core Melt Progression and Reactor Pressure Vessel Integrity

    Directory of Open Access Journals (Sweden)

    Siniša Šadek

    2010-01-01

    Full Text Available RELAP5/SCDAPSIM and MAAP4 are two widely used severe accident computer codes for the integral analysis of the core and the reactor pressure vessel behaviour following the core degradation. The objective of the paper is the comparison of code results obtained by application of different modelling options and the evaluation of influence of thermal hydraulic behaviour of the plant on core damage progression. The analysed transient was postulated station blackout in NPP Krško with a leakage from reactor coolant pump seals. Two groups of calculations were performed where each group had a different break area and, thus, a different leakage rate. Analyses have shown that MAAP4 results were more sensitive to varying thermal hydraulic conditions in the primary system. User-defined parameters had to be carefully selected when the MAAP4 model was developed, in contrast to the RELAP5/SCDAPSIM model where those parameters did not have any significant impact on final results.

  18. Heart bypass surgery - minimally invasive - discharge

    Science.gov (United States)

    ... invasive direct coronary artery bypass - discharge; MIDCAB - discharge; Robot assisted coronary artery bypass - discharge; RACAB - discharge; Keyhole ... M. is also a founding member of Hi-Ethics and subscribes to the principles of the Health ...

  19. Current peripheral bypass surgery: various clinical studies

    NARCIS (Netherlands)

    Slaa, Alexander te

    2011-01-01

    Substantial post-operative edema occurs in the majority of patients who undergo peripheral bypass surgery due to severe peripheral arterial disease (PAD). The pathophysiological mechanisms that underlay edema formation following peripheral bypass surgery include hyperemia, an increased capillary per

  20. Technology Solutions Case Study: Preventing Thermal Bypass

    Energy Technology Data Exchange (ETDEWEB)

    none,

    2012-10-01

    This project highlights the importance of continuous air barriers in full alignment with insulation to prevent thermal bypasses and achieve high energy performance, and recommends use of ENERGY STAR's Thermal Bypass Inspection Checklist.

  1. Perforation in the bypassed stomach following laparoscopic Roux-en-Y gastric bypass.

    Science.gov (United States)

    Papasavas, Pavlos K; Yeaney, Woodrow W; Caushaj, Philip F; Keenan, Robert J; Landreneau, Rodney J; Gagné, Daniel J

    2003-10-01

    Access to the bypassed stomach is difficult following laparoscopic Roux-en-Y gastric bypass (LRYGBP). The bypassed stomach is not readily available for endoscopic or radiographic evaluation. Diagnosis and treatment of peptic ulcer disease and its complications in the excluded stomach becomes difficult. We present a case of perforation in the bypassed stomach following LRYGBP secondary to peptic ulcer disease.

  2. 40 CFR 403.17 - Bypass.

    Science.gov (United States)

    2010-07-01

    ... 40 Protection of Environment 28 2010-07-01 2010-07-01 true Bypass. 403.17 Section 403.17... GENERAL PRE-TREAT-MENT REGULATIONS FOR EXIST-ING AND NEW SOURCES OF POLLUTION § 403.17 Bypass. (a) Definitions. (1) Bypass means the intentional diversion of wastestreams from any portion of an Industrial...

  3. Undiagnosed phaeochromocytoma following infrainguinal bypass surgery

    DEFF Research Database (Denmark)

    Levi, N; Schroeder, T V

    1998-01-01

    We present a rare case of undiagnosed phaeochromocytoma following infrainguinal bypass surgery. The patient, a 59-year-old lady, had a one year history of hypertension following a first femoro-tibial bypass and presented as a cardiorespiratory emergency in the admission room following her...... contralateral femoro-tibial bypass. The patient recovered after some days in intensive care despite a delayed diagnosis....

  4. In situ bypass og diabetes

    DEFF Research Database (Denmark)

    Jensen, Leif Panduro; Schroeder, T V; Lorentzen, J E

    1993-01-01

    From 1986 through to 1990 a total of 483 in situ bypass procedures were performed in 444 patients. Preoperative risk-factors were equally distributed among diabetic (DM) and non-diabetic (NDM) patients, except for smoking habits (DM:48%, NDM:64%, p = 0.002) and cardiac disease (DM:45%, NDM:29%, p...

  5. Deep-water sediment bypass

    NARCIS (Netherlands)

    Stevenson, Christopher J.; Jackson, Christopher A L; Hodgson, David M.; Hubbard, Stephen M.; Eggenhuisen, Joris T.

    2015-01-01

    Submarine gravity flows are a key process for transporting large volumes of sediment from the continents to the deep sea. The location, volume, and character of the sediment bypassed by these flows dictates the areal extent and thickness of the associated deposits. Despite its importance, sediment b

  6. Vessel Operator System

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Operator cards are required for any operator of a charter/party boat and or a commercial vessel (including carrier and processor vessels) issued a vessel permit from...

  7. Vessel Activity Record

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — The Vessel Activity Record is a bi-weekly spreadsheet that shows the status of fishing vessels. It records whether fishing vessels are fishing without an observer...

  8. Efficiency Biliopancreatic bypass surgery in bulimia nervosa

    Directory of Open Access Journals (Sweden)

    Yu I Yashkov

    2008-06-01

    Full Text Available A clinical significance in the treatment of bulimia nervosa patients with morbid obesity had already been raised [10, 13], but we did not find publications on the effectiveness of bariatric surgery in these cases. There is also information about the possibility of applying the operation bilio-pancreatic bypass, effective in patients with morbid obesity with uncontrolled eating behavior for the treatment of patients with anorexia BILIM not suffering from morbid obesity. In this article the data of clinical observation of a small sample of patients. As a result, the treatment of these patients found that severe nervous BILIM can be seen as a latent form of morbid obesity. The choice of treatment should depend not only on the initial body weight of the patient, but also on the severity of the nervous BILIM. Unsuccessful attempts at organized-balanced, conservative treatment of patients with severe bulimia nervosa may be considered a variant of surgical treatment, while bilio-pancreatic bypass surgery is considered as the most preferred operation, compared with the installation of the gastric balloon and others. All candidates for surgical treatment of obesity must identify clinical signs of bulimia nervosa, as this may influence the choice of method of operation. Further study of the role of hyperinsulinemia, secretion of ghrelin, leptin, intestinal peptide may contribute to the elucidation of the true causes of bulimia nervosa, probably has a similar origin with morbid obesity.

  9. Bypass materials in vascular surgery

    Science.gov (United States)

    Eidt, Daniela; Roll, Stephanie; Kulp, Werner; Müller-Nordhorn, Jaqueline; Vauth, Christoph; Greiner, Wolfgang; Willich, Stefan N.; von der Schulenburg, Johann-Matthias

    2006-01-01

    Introduction Arteriosclerotic changes can lead to circulatory disturbances in various areas of the human vascular system. In addition to pharmacological therapy and the management of risk factors (e. g. hypertension, diabetes, lipid metabolism disorders, and lifestyle), surgical interventions also play an important role in the treatment of arteriosclerosis. Long-segment arterial occlusions, in particular, can be treated successfully with bypass sur-gery. A number of different materials are available for this type of operation, such as autologous vein or pros-thetic grafts comprised of polytetrafluoroethylene (PTFE) or Dacron®. Prosthetic materials are used especially in the treatment of peripheral artery disease, such as in aortoiliac or femoropopliteal bypass surgery. The present report will thus focus on this area in order to examine the effectiveness of different bypass materials. Among the efforts being made to refine the newly introduced DRG system in Germany, analysing the different bypass materials used in vascular surgery is particularly important. Indeed, in its current version the German DRG system does not distinguish between bypass materials in terms of reimbursement rates. Differences in cost structures are thus of especial interest to hospitals in their budget calculations, whereas both private and statutory health insurance funds are primarily interested in long-term results and their costs. Objectives The goal of this HTA is to compare the different bypass materials used in vascular surgery in terms of their medical efficiency and cost-effectiveness, as well as with regard to their ethical, social and legal implications. In addition, this report aims to point out the areas in which further medical, epidemiological and health economic research is still needed. Methods Relevant publications were identified by means of a structured search of databases accessed through the German Institute of Medical Documentation and Information (DIMDI), as well as by

  10. Effects of angiotensin-converting enzyme inhibition in low-risk patients early after coronary artery bypass surgery

    NARCIS (Netherlands)

    Rouleau, Jean L.; Warnica, Wayne J.; Baillot, Richard; Block, Pierre J.; Chocron, Sidney; Johnstone, David; Myers, Martin G.; Calciu, Cristina-Dana; Dalle-Ave, Sonia; Martineau, Pierre; Mormont, Christine; van Gilst, Wiek H.

    2008-01-01

    Background-Early after coronary artery bypass surgery (CABG), activation of numerous neurohumoral and endogenous vasodilator systems occurs that could be influenced favorably by angiotensin-converting enzyme inhibitors. Methods and Results-The Ischemia Management with Accupril post -bypass Graft via

  11. Interventions in infrainguinal bypass grafts; Interventionen an infrainguinalen Bypaessen

    Energy Technology Data Exchange (ETDEWEB)

    Schoder, M.; Cejna, M.; Lammer, J. [Univ. Klinik fuer Radiodiagnostik, Wien (Austria). Abt. fuer Angiographie und Interventionelle Radiologie

    2001-12-01

    The long-term success of infrainguinal bypass grafts depends on meticulous surgical technique and a periodic program of postoperative surveillance. Duplex scanning is the method of choice for the detection of stenotic lesions that threaten graft patency. As an alternative to surgery, PTA is gaining increasing acceptance for the treatment of non-recurrent, short, and single stenotic lesions, despite somewhat controversial opinions. The initial technical success rates for PTA were reported to be up to 100%, and a 5-year primary assisted patency rate of up to 65% has been achieved. Some authors favorize intra-arterial infusion of fibrinolytic agents for the treatment of bypass graft occlusion with technical success rates of up to 92%. In addition to a reduced trauma compared to surgical thrombectomy, of the venous wall the advantage of thrombolytic therapy is clot lysis in run-off vessels, and uncovering of the stenotic lesions. This stenosis may then be treated by an endovascular or surgical approach. (orig.) [German] Der Langzeiterfolg infrainguinaler Bypaesse wird vor allem durch Anastomosenstenosen, seltener durch Stenosen im Bypass selbst, bestimmt. Neben exakten Operationstechniken ist deshalb eine regelmaessige postoperative Ueberwachung des Bypasses zur Verbesserung der Langzeitdurchgaengigkeit allgemein akzeptiert. Zur Identifizierung von bypassgefaehrdenden Stenosen hat die Duplexsonographie als Untersuchungsmodalitaet der Wahl einen fixen Stellenwert erlangt. Die perkutane transluminale Angioplastie (PTA) ist eine sinnvolle, minimal invasive Alternative zur offenen chirurgischen Revision von erstmalig aufgetretenen kurzstreckigen und singulaeren Bypassstenosen respektive Anastomosenstenosen. Primaer technische Erfolgsraten nach PTA werden bis zu 100%, primaer assistierte 5-Jahres-Offenheitsraten bis zu 65% angegeben. Die intraarterielle Thrombolyse bei Bypassthrombosen ist mit bis zu 92%iger technischer Erfolgsrate von manchen Arbeitsgruppen als primaere

  12. Bypass Gástrico BII.

    OpenAIRE

    Himpens, Jaques

    2014-01-01

    Hay varias técnicas de bypass gástrico para la reducción del peso, la cual se decide dependiendo de la historia, hábitos dietéticos, evaluación psicológica, estado médico, reflujo gastroesofágico, diabetes. El bypass gástrico Roux-en-Y es la única opción en 50% de los pacientes debido a reflujo, diabetes o ambas. Estos pacientes tienen ciertas características como el IMC, síndrome metabólico y diabetes. Los pacientes obesos presentan mayor resistencia a la insulina, que se encuentra regulada ...

  13. Tubular inverse opal scaffolds for biomimetic vessels

    Science.gov (United States)

    Zhao, Ze; Wang, Jie; Lu, Jie; Yu, Yunru; Fu, Fanfan; Wang, Huan; Liu, Yuxiao; Zhao, Yuanjin; Gu, Zhongze

    2016-07-01

    There is a clinical need for tissue-engineered blood vessels that can be used to replace or bypass damaged arteries. The success of such grafts depends strongly on their ability to mimic native arteries; however, currently available artificial vessels are restricted by their complex processing, controversial integrity, or uncontrollable cell location and orientation. Here, we present new tubular scaffolds with specific surface microstructures for structural vessel mimicry. The tubular scaffolds are fabricated by rotationally expanding three-dimensional tubular inverse opals that are replicated from colloidal crystal templates in capillaries. Because of the ordered porous structure of the inverse opals, the expanded tubular scaffolds are imparted with circumferentially oriented elliptical pattern microstructures on their surfaces. It is demonstrated that these tailored tubular scaffolds can effectively make endothelial cells to form an integrated hollow tubular structure on their inner surface and induce smooth muscle cells to form a circumferential orientation on their outer surface. These features of our tubular scaffolds make them highly promising for the construction of biomimetic blood vessels.There is a clinical need for tissue-engineered blood vessels that can be used to replace or bypass damaged arteries. The success of such grafts depends strongly on their ability to mimic native arteries; however, currently available artificial vessels are restricted by their complex processing, controversial integrity, or uncontrollable cell location and orientation. Here, we present new tubular scaffolds with specific surface microstructures for structural vessel mimicry. The tubular scaffolds are fabricated by rotationally expanding three-dimensional tubular inverse opals that are replicated from colloidal crystal templates in capillaries. Because of the ordered porous structure of the inverse opals, the expanded tubular scaffolds are imparted with circumferentially

  14. Evaluation of retrospectively ECG-gated 4-row multidetector CT in patients planned for minimal invasive coronary artery bypass grafting; Die EKG-getriggerte 4-Zeilen-Spiral-CT des Herzens in der praeoperativen Bildgebung vor minimalinvasiver koronarer Bypass-Operation

    Energy Technology Data Exchange (ETDEWEB)

    Begemann, P.G.C.; Ittrich, H.; Koops, A.; Adam, G.; Weber, C. [Klinik und Poliklinik fuer Diagnostische und Interventionelle Radiologie, Radiologisches Zentrum, Universitaetsklinikum, Hamburg (Germany); Arnold, M.; Detter, C.; Boehm, D.H.; Reichenspurner, H. [Universitaetsklinikum Hamburg-Eppendorf, Herzzentrum, Herz und Gefaesschirurgie, Hamburg (Germany)

    2005-08-01

    Purpose: Minimal invasive direct coronary artery bypass grafting (MIDCAB) or off-pump coronary artery bypass grafting (OPCAB) on the beating heart with full or mini-sternotomy are becoming more common in coronary bypass surgery of the left anterior descending (LAD). In the decision, which surgical approach (MIDCAB, OPCAB or conventional surgery with cardiopulmonary bypass) will be best used, knowledge of the anatomical field is of major importance. The aim of the study was to evaluate retrospective ECG-gated 4-row multidetector CT (MDCT) in patients planned for MIDCAB as additional imaging to coronary angiography. Material and methods: The study included 25 consecutive patients. MSCT was performed as unenhanced (collimation 4 x 2.5 mm) and contrast-enhanced examination (140-170 ml, 300 mg Iodine/ml, collimation 4 x 1 mm). The evaluation included presence of LAD calcifications, distance of LAD and left internal mammarian artery (LIMA), coursek of LAD and LIMA, the presence or absence of bridging through myocardium or epicardial fat and the presence of pleural fibrosis. The MDCT results were correlated with intra-operative findings. Results: All MDCTs could be assessed with reference to the demands. In 20/25 operations, MDCT had direct influence as to the selection of the surgical approach (11 MIDCAB, 7 OPCAB with mini-sternotomy and 5 with full sternotomy, 2 conventional surgeries). The distance of LAD and LIMA varied from 0.9 to 4.5 cm in MDCT. As to calcifications, 3/25 correlated patients had calcifications and 10 patients had no calcifications in the middle LAD. Seven patients had intraoperative fibrosis of the vessel wall without calcification of the middle LAD, which could not be detected with MDCT. Another 5 patients had single calcified plaques in the middle LAD, 4 of these had a fibrosis of the vessel and 1 had a normal vessel at surgery. In these cases, the anastomosis was done between the calcified plaques. No myocardial bridging was detected by MDCT and

  15. Reconnaissance Report Yolo Bypass, California

    Science.gov (United States)

    1992-03-01

    proximity of these plans, a plan for one area could not be constructed separately without creating major hydraulic impacts to the other area. In essence ...native woody species which may be commonly found include eucalyptus , acacia, giant reed, and honey locust. Yolo Bypass. In the project area, vegetation...forbs form an often dense ground cover. Non- native woody species which may be commonly found include eucalyptus , acacia, giant reed and honey locust

  16. 吸烟对冠状动脉旁路移植术后生存质量的影响%Influence of smoking on quality of life in patients after coronary artery bypass graft surgery

    Institute of Scientific and Technical Information of China (English)

    魏利娟; 高文根; 王鹏华

    2014-01-01

    目的:研究吸烟对冠状动脉旁路移植术(CABG)后早期生存质量的影响。方法随机入选2011年1月~2013年1月接受冠状动脉旁路移植术,并符合纳入标准的连续患者共120例。根据术前是否有吸烟史,分为吸烟组(60例)和未吸烟组(60例),分别在术后3、6、12个月向患者发放SF-36(short form-36)生存质量调查量表,对患者生存质量予以评定,分析吸烟对患者术后生存质量的影响。结果与未吸烟组比较,吸烟组患者冠状动脉旁路移植术后3、6、12个月躯体健康评分(PCS)和精神健康评分(MCS)以及生存质量总评分QOL均降低,差异有统计学意义(P<0.01)。结论与未吸烟组比较,吸烟组患者冠状动脉旁路移植术后早期生存质量降低,吸烟是影响冠状动脉旁路移植术后早期生存质量恢复不佳的危险因素。%Objective To assess the influence of smoking on early quality of life (QOL) in patients after coronary artery bypass graft (CABG) surgery.Methods The prospective study included 120 consecutive patients undergoing CABG between January 2011 and January 2013, who met inclusion criteria and completed short form-36 (SF-36) health status survey at 3 months, 6 months, 12 months after CABG. According to preoperative smoking history, divided into smoking group (60 cases) and non-smoking group (60 cases). Changes of quality of life and the influence of smoking on early quality of life in patients after CABG were analyzed.Results Compared with non-smoking, physical component summary (PCS) and mental component summary (MCS) and QOL total scores about smoking group of patients were lower at 3 months, 6 months, 12 months after CABG (P<0.01), the difference was statistically significant.Conclusion Compared with non-smoking, early QOL after CABG on smoking group of patients is reduced, smoking is risk factor to affect early QOL after CABG .

  17. Predicting the Glycemic Response to Gastric Bypass Surgery in Patients With Type 2 Diabetes

    OpenAIRE

    John B Dixon; Chuang, Lee-Ming; Chong, Keong; Chen, Shu-Chun; Lambert, Gavin W; Straznicky, Nora E.; Lambert, Elisabeth A.; Lee, Wei-Jei

    2012-01-01

    OBJECTIVE To find clinically meaningful preoperative predictors of diabetes remission and conversely inadequate glycemic control after gastric bypass surgery. Predicting the improvement in glycemic control in those with type 2 diabetes after bariatric surgery may help in patient selection. RESEARCH DESIGN AND METHODS Preoperative details of 154 ethnic Chinese subjects with type 2 diabetes were examined for their influence on glycemic outcomes at 1 year after gastric bypass. Remission was defi...

  18. Comparison of Two-year Outcomes between Drug-eluting Stent Implantation and Coronary Artery Bypass Grafting in Smoking Patients with Three-vessel Coronary Artery Disease%吸烟的冠状动脉三支病变患者药物洗脱支架置入术与冠状动脉搭桥术2年疗效比较

    Institute of Scientific and Technical Information of China (English)

    吴迪; 齐国先

    2011-01-01

    Objective To compare the two-year outcomes between percutaneous coronary intervention with drug-eluting stents (DES-PCI) and coronary artery bypass grafting (CABG) in smoking patients with three-vessel coronary artery disease. Methods 206 smoking patients with three-vessel coronary artery disease who received revascularization treatment between July 2006 and April 2008 were enrolled and divided into PCI group (n =108) and CABG group (n =98). Differences in two-year occurrence of Major Adverse Cardiac and Cerebrovascular Event (MACCE) and death rate between PCI group and CABG group were observed. Results There were no statistically significant differences in MACCE occurrence and death rate within 2 years between PCI group and CABG group (18.5% vs 12.2% ,P > 0.05 ;5.6% vs 8.2%, P > 0.05). Age and left ventricular efiusion traction (LVEF) were independent risk factors (P =0.033, P < 0.05). Conclusion For the treatment of smoking patients with three-vessel coronary artery disease,DES-PCI showed equivalent two-year effectiveness with CABG. Age and LVEF are independent risk factors of death.%评价吸烟的冠状动脉三支病变患者药物洗脱支架置入术( DES-PCI)与冠状动脉搭桥术(CABG)2年的临床疗效.方法 连续入选2006年7月至2008年4月间进行血运重建治疗的206例吸烟的三支病变患者,分为PCI组(108例)和CABG组(98例),观察术后2年2组患者主要不良心脑血管事件(MACCE)发生率及全因死亡率的差异.结果 PCI组与CABG组2年MACCE发生率差异无统计学意义(18.5%:12.2%,P> 0.05),PCI组再次血运重建率高于CABG组,差异有统计学意义(9.3%:2.0%,P< 0.05).2组全因死亡率差异无统计学意义(5.6%:8.2%,P>0.05),其中年龄与左室射血分数是影响预后的因素(P<0.05).结论 吸烟的三支病变患者行DES-PCI进行血运重建治疗与行CABG治疗在2年内疗效相当,年龄与左室射血分数为影响预后的因素.

  19. BIOASSAY VESSEL FAILURE ANALYSIS

    Energy Technology Data Exchange (ETDEWEB)

    Vormelker, P

    2008-09-22

    Two high-pressure bioassay vessels failed at the Savannah River Site during a microwave heating process for biosample testing. Improper installation of the thermal shield in the first failure caused the vessel to burst during microwave heating. The second vessel failure is attributed to overpressurization during a test run. Vessel failure appeared to initiate in the mold parting line, the thinnest cross-section of the octagonal vessel. No material flaws were found in the vessel that would impair its structural performance. Content weight should be minimized to reduce operating temperature and pressure. Outer vessel life is dependent on actual temperature exposure. Since thermal aging of the vessels can be detrimental to their performance, it was recommended that the vessels be used for a limited number of cycles to be determined by additional testing.

  20. Factors influencing the effect of gastric bypass surgery on type-2 diabetes mellitus%影响胃转流术治疗2型糖尿病疗效的相关因素分析

    Institute of Scientific and Technical Information of China (English)

    闫洪涛; 汤礼军; 陈涛; 蒋利; 李运明; 胡睿东; 崔建峰; 田伏洲

    2013-01-01

    Objective To investigate the factors influencing the effect of gastric bypass surgery on type-2 diabetes mellitus.Methods The clinical data of 99 patients with type-2 diabetes mellitus who received gastric bypass surgery at the General Hospital of Chengdu Military Command from March 2009 to March 2010 were retrospectively analyzed.All the patients were followed up for 1 year.The results of oral glucose tolerance test (OGTr) and C-peptid release test were obtained,the levels of insulin and glycosylated hemoglobin (HbAlc) were dynamically monitored,and the insulin resistance indexes (HOMA-IR) and body mass indexes (BMI) were calculated.Complete clinical remission was defined as not requiring any hypoglycemic measures and capable of maintaining long-term random blood glucose levels < 11.1 mmol/L,fasting blood glucose levels < 7.0 mmol/L,2-hour blood glucose levels < 11.1 mmol/L and HbAlc < 6.5%; improved condition was defined as having a significant reduction in necessary drug administration or dietary modifcation to control normal blood glucose levels after surgery; any patient who did not meet these criteria was considered unaffected.All data were analyzed using the repeated measures design,one-way analysis of variance or LSD-t test.Results Of the 99 patients,79 patients (80%) met the criteria of complete remission,the conditions of 9 patients (9%) were improved,and the surgery was ineffective in 11 patients (11%).The preoperative body weight,BMI,fasting,30 minutes and 1-,2-,3-hour postprandial C-peptide,30 minutes and 1-hour postprandial glucose,30 minutes and 1-hour postprandial insulin were (75 ± 14)kg,(27 ±4) kg/m2,(2.1 ±0.8) nmol/L,(2.8 ± 1.2)nmol/L,(3.8 ± 1.7) nmol/L,(4.5 ± 2.2) nmol/L,(3.5 ± 1.2) nmol/L,(16 ± 3) mmol/L,(19 ± 4) mmol/L,(29 ± 21) U/L,(37 ± 27) U/Lfor patients with complete remission,(62 ± 10) kg,(24 ± 4) kg/m2,(1.3 ± 0.5) nmol/L,(1.8 ± 1.0) nmol/L,(1.9 ± 0.8) nmol/L,(2.8 ± 1.7) nmol/L,(2.7 ± 1.5) nmol/L,(17

  1. Use of Janke-Barron retractor for exposure of the arteries during bypass surgery.

    Science.gov (United States)

    Bridges, K G; Tomasello, D N; Hoffman, W S; MacVaugh, H

    1982-09-01

    The Janke-Barron heart support was used successfully on 1500 patients who required coronary artery bypass surgery to at least two vessels. The significant advantages it provided were improved exposure and access to all coronary arteries, elimination of damage caused by an assistant holding the heart, provision of a dryer operating field, and allowance for a smaller incision without compromising exposure of the heart.

  2. Coronary artery bypass grafting in a patient with active idiopathic cryoglobulinemia: revisiting the issue

    Directory of Open Access Journals (Sweden)

    Hafiz Abdul Moiz Fakih

    2016-02-01

    Full Text Available Background: Cryoglobulinemia is a cold-reactive autoimmune disease. It is of distinctive importance in cardiac surgery because of the use of hypothermic cardiopulmonary bypass (CPB. Cryoglobulins, which activate at variable levels of hypothermia, can cause precipitation during surgery leading to possibly severe leukocytoclastic or necrotizing vasculitis, clinically manifested as ischemic events, such as cutaneous ulcerations, glomerulonephritis, arthritis, or peripheral neuropathies among the most reported associated comorbidities. Management of CPB and systemic protection in this rare but unique scenario requires individualized planning. We report the case of a patient with active cryoglobulinemia who was preoperatively managed with plasmapheresis. He underwent hypothermic coronary bypass with no precipitation and flare during and after surgery. Case presentation: We describe the case of a 59-year-old Caucasian male with clinically significant idiopathic cryoglobulinemia and history of recurrent skin lesions and toe amputations secondary to cold exposure. He presented with 2-h duration of chest pain and new onset atrial fibrillation. After cardiac catheterization, a diagnosis of three-vessel coronary artery disease was established and coronary artery bypass grafting (CABG was scheduled. Because of a high risk of flare-up during surgery, the patient was preemptively treated with two sessions of plasmapheresis before bypass. He then underwent hypothermic CABG. The pre- and perioperative course was unremarkable without any clinical evidence of precipitation. The patient was discharged on day 6 postoperatively without any complications. Conclusion: Preoperative plasmapheresis before hypothermic coronary bypass can prevent fatal cryoglobulinemia-related complications in patients with active disease.

  3. Experimental Study of the APR+ Direct ECC Bypass in the Air-water Test Facility

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Kihwan; Choi, Hae-Seob; Park, Kil-won; Kwon, Tae-Soon [Korea Atomic Energy Research Institute, Daejeon (Korea, Republic of)

    2015-10-15

    The APR+ is an improved Korean Nuclear Power Reactor, which has been developed as a two loop evolutionary PWR (Pressure Water Reactor) with a number of advanced design features to enhance safety based on the APR-1400 technology. The emergency core cooling system (ECC) of the APR+ is different with that of the APR-1400, though the APR+ adopted a direct vessel injection (DVI) system which is the same design features of the APR-14000. The main difference of the DVI+ is the emergency core barrel duct (ECBD) which is designed to increase the amount of the injection water to the core region. The performance of the DVI system has been an important issues for past decades, and many researchers have studied the related thermal-hydraulic technical issues such as the ECC bypass fraction, the steam condensation effect, temperature distribution, sub-cooling margin, and etc. However, the previous research cannot be directly applicable to the APR+ owing to the unique features of the DVI+. The current study will elaborate on the experimental evaluation of the direct ECC bypass performance. The 1/5 ECC bypass test facility which is designed with a linearly reduced 1/5 scale referring to the APR+ was used to investigate the effect of the DVI+ injection nozzle location and the broken cold leg velocity on the direct ECC bypass fraction. However, air is used as a working fluid to simulate the steam flow induced from the broken cold leg, and thus, the direct contact condensation effect is not considered in this study. Experimental study for the direct ECC bypass phenomena has been carryout out with various the injection mode and air velocity conditions. The tests were performed in the 1/5 scale ECC bypass test facility, and the test condition was defined using a scaling law referring to the APR+ reactor. Test results showed that the direct ECC bypass fraction was greatly enhanced compared with the reference test (w/o ECBD)

  4. History of cardiopulmonary bypass (CPB).

    Science.gov (United States)

    Hessel, Eugene A

    2015-06-01

    The development of cardiopulmonary bypass (CPB), thereby permitting open-heart surgery, is one of the most important advances in medicine in the 20th century. Many currently practicing cardiac anesthesiologists, cardiac surgeons, and perfusionists are unaware of how recently it came into use (60 years) and how much the practice of CPB has changed during its short existence. In this paper, the development of CPB and the many changes and progress that has taken place over this brief period of time, making it a remarkably safe endeavor, are reviewed. The many as yet unresolved questions are also identified, which sets the stage for the other papers in this issue of this journal.

  5. Gut hormones and gastric bypass

    DEFF Research Database (Denmark)

    Holst, Jens J.

    2016-01-01

    , oxyntomodulin, neurotensin and peptide YY (PYY). However, some proximal hormones also show changes probably reflecting that the distribution of these hormones is not restricted to the bypassed segments of the gut. Thus, cholecystokinin responses are increased, whereas gastric inhibitory polypeptide responses......%. The increased insulin responses after the operation, one of the important mechanisms whereby these operations cause diabetes remission, is clearly due to a combination of the increased glucose absorption rates and the exaggerated GLP-1 secretion. The hormonal changes are therefore very important...

  6. Off-Pump Triple Coronary Artery Bypass Grafting in a Patient with Situs Inversus Totalis: Case Presentation and a Brief Review of the Brazilian and the International Experiences

    Science.gov (United States)

    Karigyo, Carlos Junior Toshiyuki; Batalini, Felipe; Murakami, Alexandre Noboru; Teruya, Rogério Toshio; Gregori Júnior, Francisco

    2016-01-01

    A 76-year-old man with situs inversus totalis underwent a successful off-pump three-vessel coronary artery bypass surgery. The postoperative course was uneventful, and the patient was discharged 8 days later. At 9-month follow-up a coronary computed tomography angiography confirmed the viability of all of the grafts, and one year after the operation the patient remained asymptomatic. It comprises the fifth Brazilian case of a coronary surgery in a patient with situs inversus totalis and the first one of the country of a coronary artery bypass surgery without the use of the cardiopulmonary bypass in this condition. PMID:27556323

  7. Probabilistic retinal vessel segmentation

    Science.gov (United States)

    Wu, Chang-Hua; Agam, Gady

    2007-03-01

    Optic fundus assessment is widely used for diagnosing vascular and non-vascular pathology. Inspection of the retinal vasculature may reveal hypertension, diabetes, arteriosclerosis, cardiovascular disease and stroke. Due to various imaging conditions retinal images may be degraded. Consequently, the enhancement of such images and vessels in them is an important task with direct clinical applications. We propose a novel technique for vessel enhancement in retinal images that is capable of enhancing vessel junctions in addition to linear vessel segments. This is an extension of vessel filters we have previously developed for vessel enhancement in thoracic CT scans. The proposed approach is based on probabilistic models which can discern vessels and junctions. Evaluation shows the proposed filter is better than several known techniques and is comparable to the state of the art when evaluated on a standard dataset. A ridge-based vessel tracking process is applied on the enhanced image to demonstrate the effectiveness of the enhancement filter.

  8. Guam Abandoned Vessel Inventory

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — NOAA Abandoned Vessel Project Data for Guam. Abandoned vessels pose a significant threat to the NOAA Trust resources through physical destruction of coral habitats...

  9. Vessel Arrival Info - Legacy

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — The Vessel Arrival Info is a spreadsheet that gets filled out during the initial stage of the debriefing process by the debriefer. It contains vessel name, trip...

  10. Florida Abandoned Vessel Inventory

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — NOAA Abandoned Vessel Project Data for Florida. Abandoned vessels pose a significant threat to the NOAA Trust resources through physical destruction of coral...

  11. David M. Hume memorial lecture. In situ vein bypass in the treatment of femoropopliteal atherosclerotic disease: a ten year study.

    Science.gov (United States)

    Hall, K V; Rostad, H

    1978-08-01

    The in situ vein bypass technic for femoropopliteal atherosclerotic disease is described. Several factors influence the long-term results, the most important being a history of myocardial disease, the size of the vein graft, and sufficient runoff.

  12. ALICE HMPID Radiator Vessel

    CERN Multimedia

    2003-01-01

    View of the radiator vessels of the ALICE/HMPID mounted on the support frame. Each HMPID module is equipped with 3 indipendent radiator vessels made out of neoceram and fused silica (quartz) windows glued together. The spacers inside the vessel are needed to stand the hydrostatic pressure. http://alice-hmpid.web.cern.ch/alice-hmpid

  13. Epicardial ultrasound in coronary artery bypass surgery

    NARCIS (Netherlands)

    Budde, R.P.J.

    2005-01-01

    Chapter 1 Coronary artery bypass surgery (CABG) is traditionally performed via a median sternotomy approach on cardiopulmonary bypass (arrested heart). Since the mid 1990ties, beating heart, minimally invasive and even totally endoscopic CABG are (re)explored. In all approaches to CABG, the surgeo

  14. Multimodality imaging of coronary artery bypass grafts

    NARCIS (Netherlands)

    Salm, Liesbeth Pauline

    2006-01-01

    This thesis describes multiple imaging modalities to examine coronary artery bypass grafts, and the research which was performed to further develop noninvasive imaging techniques to detect stenoses in native coronary arteries and bypass grafts in patients who experienced recurrent chest pain after c

  15. In situ saphenous vein bypass surgery in diabetic patients

    DEFF Research Database (Denmark)

    Jensen, L P; Schroeder, T V; Lorentzen, J E

    1992-01-01

    .005). Indication for surgery was gangrene or ulceration in 57% of diabetics, as opposed to 36% in non-diabetic patients (p = 0.0002). A femoro-popliteal bypass was performed in 18% of patients, whereas 82% received an infrapopliteal procedure, of which 42% were to the distal third of the calf or foot. Diabetic......From 1986 through to 1990 a total of 483 consecutive in situ infra-inguinal vein bypass procedures were performed in 444 patients, of whom 112 (25%) were diabetics (57 insulin dependent diabetes mellitus and 55 non-insulin-dependent diabetes mellitus). Based on a prospective vascular data registry...... this material was analysed to determine the influence of diabetes on the outcome. Preoperative risk factors were equally distributed among diabetic and non-diabetic patients, except for smoking habits (diabetics: 48%; non-diabetics: 64%, p = 0.002) and cardiac disease (diabetics: 45%; non-diabetics: 29%, p = 0...

  16. STCW公约对救助船员培训的影响与应用%The influence and application of the STCW convention to seafarers on board rescue vessels

    Institute of Scientific and Technical Information of China (English)

    李新华

    2013-01-01

    This paper gave a general introduction of the background and the main points of the Manila amendments to the STCW convention, and analyzed the influence and application for the training of seafarers on board rescue vessels.%  文中介绍了STCW公约马尼拉修正案产生的背景及修正内容,提出了履行公约对救助船员培训的相关影响及应用。

  17. Anesthesia for off-pump coronary artery bypass surgery

    Directory of Open Access Journals (Sweden)

    Thomas M Hemmerling

    2013-01-01

    Full Text Available The evolution of techniques and knowledge of beating heart surgery has led anesthesia toward the development of new procedures and innovations to promote patient safety and ensure high standards of care. Off-pump coronary artery bypass (OPCAB surgery has shown to have some advantages compared to on-pump cardiac surgery, particularly the reduction of postoperative complications including systemic inflammation, myocardial injury, and cerebral injury. Minimally invasive surgery for single vessel OPCAB through a limited thoracotomy incision can offer the advantage of further reduction of complications. The anesthesiologist has to deal with different issues, including hemodynamic instability and myocardial ischemia during aorto-coronary bypass grafting. The anesthesiologist and surgeon should collaborate and plan the best perioperative strategy to provide optimal care and ensure a rapid and complete recovery. The use of high thoracic epidural analgesia and fast-track anesthesia offers particular benefits in beating heart surgery. The excellent analgesia, the ability to reduce myocardial oxygen consumption, and the good hemodynamic stability make high thoracic epidural analgesia an interesting technique. New scenarios are entering in cardiac anesthesia: ultra-fast-track anesthesia with extubation in the operating room and awake surgery tend to be less invasive, but can only be performed on selected patients.

  18. Measurement of canine pancreatic perfusion using dynamic computed tomography: Influence of input-output vessels on deconvolution and maximum slope methods

    Energy Technology Data Exchange (ETDEWEB)

    Kishimoto, Miori, E-mail: miori@mx6.et.tiki.ne.jp [Department of Clinical Veterinary Science, Obihiro University of Agriculture and Veterinary Medicine, Nishi 2-11 Inada-cho, Obihiro 080-8555 (Japan); Tsuji, Yoshihisa, E-mail: y.tsuji@extra.ocn.ne.jp [Department of Gastroenterology and Hepatology, Kyoto University Graduate School of Medicine, Shogoinkawara-cho 54, Sakyo-ku 606-8507 (Japan); Katabami, Nana; Shimizu, Junichiro; Lee, Ki-Ja [Department of Clinical Veterinary Science, Obihiro University of Agriculture and Veterinary Medicine, Nishi 2-11 Inada-cho, Obihiro 080-8555 (Japan); Iwasaki, Toshiroh [Department of Veterinary Internal Medicine, Tokyo University of Agriculture and Technology, Saiwai-cho, 3-5-8, Fuchu 183-8509 (Japan); Miyake, Yoh-Ichi [Department of Clinical Veterinary Science, Obihiro University of Agriculture and Veterinary Medicine, Nishi 2-11 Inada-cho, Obihiro 080-8555 (Japan); Yazumi, Shujiro [Digestive Disease Center, Kitano Hospital, 2-4-20 Ougi-machi, Kita-ku, Osaka 530-8480 (Japan); Chiba, Tsutomu [Department of Gastroenterology and Hepatology, Kyoto University Graduate School of Medicine, Shogoinkawara-cho 54, Sakyo-ku 606-8507 (Japan); Yamada, Kazutaka, E-mail: kyamada@obihiro.ac.jp [Department of Clinical Veterinary Science, Obihiro University of Agriculture and Veterinary Medicine, Nishi 2-11 Inada-cho, Obihiro 080-8555 (Japan)

    2011-01-15

    Objective: We investigated whether the prerequisite of the maximum slope and deconvolution methods are satisfied in pancreatic perfusion CT and whether the measured parameters between these algorithms are correlated. Methods: We examined nine beagles injected with iohexol (200 mgI kg{sup -1}) at 5.0 ml s{sup -1}. The abdominal aorta and splenic and celiac arteries were selected as the input arteries and the splenic vein, the output veins. For the maximum slope method, we determined the arterial contrast volume of each artery by measuring the area under the curve (AUC) and compared the peak enhancement time in the pancreas with the contrast appearance time in the splenic vein. For the deconvolution method, the artery-to-vein collection rate of contrast medium was calculated. We calculated the pancreatic tissue blood flow (TBF), tissue blood volume (TBV), and mean transit time (MTT) using both algorithms and investigated their correlation based on vessel selection. Results: The artery AUC significantly decreased as it neared the pancreas (P < 0.01). In all cases, the peak time of the pancreas (11.5 {+-} 1.6) was shorter than the appearance time (14.1 {+-} 1.6) in the splenic vein. The splenic artery-vein combination exhibited the highest collection rate (91.1%) and was the only combination that was significantly correlated between TBF, TBV, and MTT in both algorithms. Conclusion: Selection of a vessel nearest to the pancreas is considered as a more appropriate prerequisite. Therefore, vessel selection is important in comparison of the semi-quantitative parameters obtained by different algorithms.

  19. Influence of Baseline Characteristics, Operative Conduct and Postoperative Course on 30-day Outcomes of Coronary Artery Bypass Grafting among Patients with Left Ventricular Dysfunction: Results from the Surgical Treatment for Ischemic Heart Failure (STICH) Trial

    Science.gov (United States)

    Wrobel, Krzysztof; Stevens, Susanna R.; Jones, Robert H.; Selzman, Craig H.; Lamy, Andre; Beaver, Thomas M.; Djokovic, Ljubomir T.; Wang, Nan; Velazquez, Eric J.; Sopko, George; Kron, Irving L.; DiMaio, J. Michael; Michler, Robert E.; Lee, Kerry L.; Yii, Michael; Leng, Chua Yeow; Zembala, Marian; Rouleau, Jean L.; Daly, Richard C.; Al-Khalidi, Hussein R.

    2015-01-01

    Background Patients with severe left ventricular (LV) dysfunction, ischemic heart failure and coronary artery disease (CAD) suitable for coronary artery bypass grafting (CABG) are at higher risk for surgical morbidity and mortality. Paradoxically, those patients with the most severe coronary artery disease and ventricular dysfunction who derive the greatest clinical benefit from CABG are also at the greatest operative risk, which makes decision-making regarding whether to proceed to surgery difficult in such patients. To better inform such decision-making, we analyzed the STICH CABG population for detailed information on perioperative risk and outcomes. Methods and Results In both STICH trials (hypotheses), 2136 patients with a left ventricular ejection fraction (LVEF) ≤ 35% and coronary artery disease were allocated to medical therapy, CABG plus medical therapy or CABG with surgical ventricular reconstruction (SVR). Relationships of baseline characteristics and operative conduct with morbidity and mortality at 30 days were evaluated. There were a total of 1460 patients who received surgery, and 346 of them (roughly, one-quarter) of these high-risk patients developed a severe complication within 30 days. Worsening renal insufficiency, cardiac arrest with cardiopulmonary resuscitation, and ventricular arrhythmias were the most frequent complications and those most commonly associated with death. Mortality at 30 days was 5.1% and was generally preceded by a serious complication (65 of 74 deaths). LV size, renal dysfunction, advanced age, and atrial fibrillation/flutter were significant preoperative predictors of mortality within 30 days. Cardiopulmonary bypass time was the only independent surgical variable predictive of 30-day mortality. Conclusions CABG can be performed with relatively low 30-day mortality in patients with LV dysfunction. Serious postoperative complications occurred in nearly 1 in 4 patients and were associated with mortality. Clinical Trial

  20. Numerical simulation of an alternative to prevent hydrates formation in a bypass section

    Energy Technology Data Exchange (ETDEWEB)

    Almeida, Lucilla Coelho; Oliveira Junior, Joao Americo Aguirre; Fonte, Clarissa Bergman [Engineering Simulation and Scientific Software Ltda. (ESSS), Florianopolis, SC (Brazil); Silva, Fabricio Soares da; Moraes, Carlos Alberto Capela [Petroleo Brasileiro S.A. (PETROBRAS), Rio de Janeiro, RJ (Brazil)

    2012-07-01

    This work presents the use of Computational Fluid Dynamics to evaluate the feasibility of MEG (monoethylene glycol) injection as an alternative to prevent hydrate formation in a bypass section, present in an inlet module of a separation device of a subsea separation system. As the bypass section is open to the main pipeline, MEG will probably be dragged due to secondary flows generated by the main flow stream. The MEG removal rate is estimated, as well as the internal heat transfer between the currents and the heat loss to the external environment in order to estimate the temperature in the equipment. In a first step, the MEG removal was evaluated considering the heat transfer between the liquid phase (composed of water, oil and MEG) and the gas phase as well as the heat transfer by forced convection to the external environment. In a second step, the influence of a thermal insulation layer around the bypass line, reducing the heat loss to the external environment, was studied. Both simulations (with or without thermal insulation) showed the establishment of secondary flows in the open connection between the main line and bypass line, promoting the removal of MEG from the bypass section and enabling other components of the liquid phase and/or gas to enter in the bypass line. This MEG removal is faster when thermal isolation was considered, due to the fact that higher temperatures are established in the bypass, maintaining the liquid phase with lower densities and viscosities. With regard to temperature, the insulation was able to keep higher temperatures at the bypass line than those obtained without insulation, indicating that the combination of MEG injection and thermal insulation may be able to avoid the critical condition for hydrate formation. (author)

  1. 30 CFR 57.19018 - Overtravel by-pass switches.

    Science.gov (United States)

    2010-07-01

    ... 30 Mineral Resources 1 2010-07-01 2010-07-01 false Overtravel by-pass switches. 57.19018 Section... Hoisting Hoists § 57.19018 Overtravel by-pass switches. When an overtravel by-pass switch is installed, the... switch is held in the closed position by the hoistman. The overtravel by-pass switch shall...

  2. 30 CFR 56.19018 - Overtravel by-pass switches.

    Science.gov (United States)

    2010-07-01

    ... 30 Mineral Resources 1 2010-07-01 2010-07-01 false Overtravel by-pass switches. 56.19018 Section... Hoisting Hoists § 56.19018 Overtravel by-pass switches. When an overtravel by-pass switch is installed, the... switch is held in the closed position by the hoistman. The overtravel by-pass switch shall...

  3. 34 CFR 76.677 - Continuation of a bypass.

    Science.gov (United States)

    2010-07-01

    ... 34 Education 1 2010-07-01 2010-07-01 false Continuation of a bypass. 76.677 Section 76.677... Be Met by the State and Its Subgrantees? Procedures for Bypass § 76.677 Continuation of a bypass. The Secretary continues a bypass until the Secretary determines that the grantee or subgrantee will meet...

  4. Pressure vessel design manual

    CERN Document Server

    Moss, Dennis R

    2013-01-01

    Pressure vessels are closed containers designed to hold gases or liquids at a pressure substantially different from the ambient pressure. They have a variety of applications in industry, including in oil refineries, nuclear reactors, vehicle airbrake reservoirs, and more. The pressure differential with such vessels is dangerous, and due to the risk of accident and fatality around their use, the design, manufacture, operation and inspection of pressure vessels is regulated by engineering authorities and guided by legal codes and standards. Pressure Vessel Design Manual is a solutions-focused guide to the many problems and technical challenges involved in the design of pressure vessels to match stringent standards and codes. It brings together otherwise scattered information and explanations into one easy-to-use resource to minimize research and take readers from problem to solution in the most direct manner possible. * Covers almost all problems that a working pressure vessel designer can expect to face, with ...

  5. Early results of coronary artery bypass grafting with coronary endarterectomy for severe coronary artery disease

    Directory of Open Access Journals (Sweden)

    Toischer Karl

    2009-09-01

    Full Text Available Abstract Background Despite the existence of controversial debates on the efficiency of coronary endarterectomy (CE, it is still used as an adjunct to coronary artery bypass grafting (CABG. This is particularly true in patients with endstage coronary artery disease. Given the improvements in cardiac surgery and postoperative care, as well as the rising number of elderly patient with numerous co-morbidities, re-evaluating the pros and cons of this technique is needed. Methods Patient demographic information, operative details and outcome data of 104 patients with diffuse calcified coronary artery disease were retrospectively analyzed with respect to functional capacity (NYHA, angina pectoris (CCS and mortality. Actuarial survival was reported using a Kaplan-Meyer analysis. Results Between August 2001 and March 2005, 104 patients underwent coronary artery bypass grafting (CABG with adjunctive coronary endarterectomy (CE in the Department of Thoracic-, Cardiac- and Vascular Surgery, University of Goettingen. Four patients were lost during follow-up. Data were gained from 88 male and 12 female patients; mean age was 65.5 ± 9 years. A total of 396 vessels were bypassed (4 ± 0.9 vessels per patient. In 98% left internal thoracic artery (LITA was used as arterial bypass graft and a total of 114 vessels were endarterectomized. CE was performed on right coronary artery (RCA (n = 55, on left anterior descending artery (LAD (n = 52 and circumflex artery (RCX (n = 7. Ninety-five patients suffered from 3-vessel-disease, 3 from 2-vessel- and 2 from 1-vessel-disease. Closed technique was used in 18%, open technique in 79% and in 3% a combination of both. The most frequent endarterectomized localization was right coronary artery (RCA = 55%. Despite the severity of endstage atherosclerosis, hospital mortality was only 5% (n = 5. During follow-up (24.5 ± 13.4 months, which is 96% complete (4 patients were lost caused by unknown address 8 patients died (cardiac

  6. Early results of coronary artery bypass grafting with coronary endarterectomy for severe coronary artery disease

    Science.gov (United States)

    Schmitto, Jan D; Kolat, Philipp; Ortmann, Philipp; Popov, Aron F; Coskun, Kasim O; Friedrich, Martin; Sossalla, Samuel; Toischer, Karl; Mokashi, Suyog A; Tirilomis, Theodor; Baryalei, Mersa M; Schoendube, Friedrich A

    2009-01-01

    Background Despite the existence of controversial debates on the efficiency of coronary endarterectomy (CE), it is still used as an adjunct to coronary artery bypass grafting (CABG). This is particularly true in patients with endstage coronary artery disease. Given the improvements in cardiac surgery and postoperative care, as well as the rising number of elderly patient with numerous co-morbidities, re-evaluating the pros and cons of this technique is needed. Methods Patient demographic information, operative details and outcome data of 104 patients with diffuse calcified coronary artery disease were retrospectively analyzed with respect to functional capacity (NYHA), angina pectoris (CCS) and mortality. Actuarial survival was reported using a Kaplan-Meyer analysis. Results Between August 2001 and March 2005, 104 patients underwent coronary artery bypass grafting (CABG) with adjunctive coronary endarterectomy (CE) in the Department of Thoracic-, Cardiac- and Vascular Surgery, University of Goettingen. Four patients were lost during follow-up. Data were gained from 88 male and 12 female patients; mean age was 65.5 ± 9 years. A total of 396 vessels were bypassed (4 ± 0.9 vessels per patient). In 98% left internal thoracic artery (LITA) was used as arterial bypass graft and a total of 114 vessels were endarterectomized. CE was performed on right coronary artery (RCA) (n = 55), on left anterior descending artery (LAD) (n = 52) and circumflex artery (RCX) (n = 7). Ninety-five patients suffered from 3-vessel-disease, 3 from 2-vessel- and 2 from 1-vessel-disease. Closed technique was used in 18%, open technique in 79% and in 3% a combination of both. The most frequent endarterectomized localization was right coronary artery (RCA = 55%). Despite the severity of endstage atherosclerosis, hospital mortality was only 5% (n = 5). During follow-up (24.5 ± 13.4 months), which is 96% complete (4 patients were lost caused by unknown address) 8 patients died (cardiac failure: 3

  7. Coronary Bypass Surgery in a 105-Year-Old Patient with Cardiopulmonary Bypass

    Directory of Open Access Journals (Sweden)

    Temucin Noyan Ogus

    2010-01-01

    Full Text Available Coronary artery bypass grafting is one of the routine daily surgical procedures in the current era. Parallel to the increasing life expectancy, cardiac surgery is commonly performed in octogenarians. However, literature consists of only seldom reports of coronary artery bypass grafting in patients above 90 years of age. In this report, we present our management strategy in a 105-year-old patient who underwent coronary artery bypass grafting at our institution.

  8. First autopsy analysis of a neovascularized arterial network induced by indirect bypass surgery for moyamoya disease: case report.

    Science.gov (United States)

    Mukawa, Maki; Nariai, Tadashi; Inaji, Motoki; Tamada, Natsumi; Maehara, Taketoshi; Matsushima, Yoshiharu; Ohno, Kikuo; Negi, Mariko; Kobayashi, Daisuke

    2016-05-01

    The object of this study was to analyze the pathology of collateral vessels newly induced by indirect bypass surgery for moyamoya disease (MMD). An autopsy analysis was conducted on a 39-year-old woman with MMD who had died of a brainstem infarction. The patient had undergone bilateral indirect bypass surgeries 22 years earlier. Sufficient revascularization via bilateral external carotid arterial systems was confirmed by cerebral angiography before her death. Macroscopic observation of the operative areas revealed countless meandering vessels on the internal surface of the dura mater connected with small vessels on the brain surface and in the subpial brain tissue. Notably, microscopic analysis of these vessels revealed the characteristic 3-layer structure of an arterial wall. This autopsy analysis was the first to confirm that indirect bypass surgery had induced the formation of a new arterial network (arteriogenesis) and that this network had been maintained for more than 20 years to compensate for the chronic cerebral ischemia caused by the MMD.

  9. 核能系统压力容器辐照脆化机制及其影响因素%IRRADIATION EMBRITTLEMENT MECHANISMS AND RELEVANT INFLUENCE FACTORS OF NUCLEAR REACTOR PRESSURE VESSEL STEELS

    Institute of Scientific and Technical Information of China (English)

    李正操; 陈良

    2014-01-01

    Nuclear reactor pressure vessel is the irreplaceable component of the nuclear power plant and its integrity is one of the key issues of any nuclear power plant for long term operations.Various nanofeatures,including solute clusters,matrix damage and grain boundary segregation formed in reactor pressure vessel steels in the face of neutron irradiation.These ultrafine microstructural features lead to an increase in the ductile brittle transition temperature as is the measure used to describe the irradiation embrittlement.The balance of features depends on the composition of the reactor pressure vessel steels and the irradiation conditions.This paper reviews the current phenomenological knowledge and understanding of the basic mechanisms and relevant influence factors for irradiation embrittlement of nuclear reactor pressure vessel steels.To be specific,the formation and evolution processes of the embrittling features are presented.Also,the influences of material variables,such as copper,nickel and manganese contents on irradiation embrittlement and those of irradiation variables,such as neutron flux and post irradiation annealing are summarized.In addition,fundamental research issues that remain to be addressed are briefly pointed out.%核反应堆压力容器作为核电站不可更换的关键性设备,其设备完整性对核电站的安全运行起着至关重要的作用.在辐照条件下,反应堆压力容器钢中会形成一系列微结构缺陷,包括溶质沉淀、基体损伤和脆性元素的晶界偏聚等,导致材料的韧脆性转变温度升高,产生辐照脆化效应.而压力容器钢的成分和辐照条件决定了各种微结构对辐照脆化的贡献大小.本文主要针对核能系统压力容器辐照脆化机制及其影响因素进行了综述,总结讨论了这些微结构的形成机制及溶质元素、辐照通量和辐照后退火对这些微结构和材料机械性能的影响,并指出了存在的问题和未来的研究方向.

  10. Maury Journals - German Vessels

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — German vessels observations, after the 1853 Brussels Conference that set International Maritime Standards, modeled after Maury Marine Standard Observations.

  11. NCSX Vacuum Vessel Fabrication

    Energy Technology Data Exchange (ETDEWEB)

    Viola, M. E.; Brown, T.; Heitzenroeder, P.; Malinowski, F.; Reiersen, W.; Sutton, L.; Goranson, P.; Nelson, B.; Cole, M.; Manuel, M.; McCorkle, D.

    2005-10-07

    The National Compact Stellarator Experiment (NCSX) is being constructed at the Princeton Plasma Physics Laboratory (PPPL) in conjunction with the Oak Ridge National Laboratory (ORNL). The goal of this experiment is to develop a device which has the steady state properties of a traditional stellarator along with the high performance characteristics of a tokamak. A key element of this device is its highly shaped Inconel 625 vacuum vessel. This paper describes the manufacturing of the vessel. The vessel is being fabricated by Major Tool and Machine, Inc. (MTM) in three identical 120º vessel segments, corresponding to the three NCSX field periods, in order to accommodate assembly of the device. The port extensions are welded on, leak checked, cut off within 1" of the vessel surface at MTM and then reattached at PPPL, to accommodate assembly of the close-fitting modular coils that surround the vessel. The 120º vessel segments are formed by welding two 60º segments together. Each 60º segment is fabricated by welding ten press-formed panels together over a collapsible welding fixture which is needed to precisely position the panels. The vessel is joined at assembly by welding via custom machined 8" (20.3 cm) wide spacer "spool pieces." The vessel must have a total leak rate less than 5 X 10-6 t-l/s, magnetic permeability less than 1.02μ, and its contours must be within 0.188" (4.76 mm). It is scheduled for completion in January 2006.

  12. Complete Blood Count and Retinal Vessel Calibers

    OpenAIRE

    Gerald Liew; Jie Jin Wang; Elena Rochtchina; Tien Yin Wong; Paul Mitchell

    2014-01-01

    OBJECTIVE: The influence of hematological indices such as complete blood count on microcirculation is poorly understood. Retinal microvasculature can be directly visualized and vessel calibers are associated with a range of ocular and systemic diseases. We examined the association of complete blood count with retinal vessel calibers. METHODS: Cross-sectional population-based Blue Mountains Eye Study, n = 3009, aged 49+ years. Complete blood count was measured from fasting blood samples taken ...

  13. Exhaust gas bypass valve control for thermoelectric generator

    Science.gov (United States)

    Reynolds, Michael G; Yang, Jihui; Meisner, Greogry P.; Stabler, Francis R.; De Bock, Hendrik Pieter Jacobus; Anderson, Todd Alan

    2012-09-04

    A method of controlling engine exhaust flow through at least one of an exhaust bypass and a thermoelectric device via a bypass valve is provided. The method includes: determining a mass flow of exhaust exiting an engine; determining a desired exhaust pressure based on the mass flow of exhaust; comparing the desired exhaust pressure to a determined exhaust pressure; and determining a bypass valve control value based on the comparing, wherein the bypass valve control value is used to control the bypass valve.

  14. MHD Energy Bypass Scramjet Engine

    Science.gov (United States)

    Mehta, Unmeel B.; Bogdanoff, David W.; Park, Chul; Arnold, Jim (Technical Monitor)

    2001-01-01

    Revolutionary rather than evolutionary changes in propulsion systems are most likely to decrease cost of space transportation and to provide a global range capability. Hypersonic air-breathing propulsion is a revolutionary propulsion system. The performance of scramjet engines can be improved by the AJAX energy management concept. A magneto-hydro-dynamics (MHD) generator controls the flow and extracts flow energy in the engine inlet and a MHD accelerator downstream of the combustor accelerates the nozzle flow. A progress report toward developing the MHD technology is presented herein. Recent theoretical efforts are reviewed and ongoing experimental efforts are discussed. The latter efforts also include an ongoing collaboration between NASA, the US Air Force Research Laboratory, US industry, and Russian scientific organizations. Two of the critical technologies, the ionization of the air and the MHD accelerator, are briefly discussed. Examples of limiting the combustor entrance Mach number to a low supersonic value with a MHD energy bypass scheme are presented, demonstrating an improvement in scramjet performance. The results for a simplified design of an aerospace plane show that the specific impulse of the MHD-bypass system is better than the non-MHD system and typical rocket over a narrow region of flight speeds and design parameters. Equilibrium ionization and non-equilibrium ionization are discussed. The thermodynamic condition of air at the entrance of the engine inlet determines the method of ionization. The required external power for non-equilibrium ionization is computed. There have been many experiments in which electrical power generation has successfully been achieved by magneto-hydrodynamic (MHD) means. However, relatively few experiments have been made to date for the reverse case of achieving gas acceleration by the MHD means. An experiment in a shock tunnel is described in which MHD acceleration is investigated experimentally. MHD has several

  15. Prophylactic digitalization for coronary artery bypass surgery.

    Science.gov (United States)

    Johnson, L W; Dickstein, R A; Fruehan, C T; Kane, P; Potts, J L; Smulyan, H; Webb, W R; Eich, R H

    1976-05-01

    One hundred and twenty patients undergoing aortocoronary bypass procedures were randomly placed into control and digitalized groups. All were initially in normal sinus rhythm and without evidence of congestive heart failure. Supraventricular arrhythmias occurred in 17 of 66 controls and in only three of 54 digitalized patients (P less than 0.01). There was no evidence of digitals toxicity. Based on this evidence we recommend prophylactic digitalization for patients having aortocoronary bypass operations.

  16. Monsanto may bypass NIH in microbe test.

    Science.gov (United States)

    Sun, Marjorie

    1985-01-11

    The Monsanto Company is planning to ask the Environmental Protection Agency for clearance to field test a genetically engineered microbial pesticide, bypassing the traditional approval process of the National Institutes of Health. Although only federally funded institutions are required to obtain NIH approval for genetic engineering tests, Monsanto is the first company to bypass the NIH regulatory process, which has become mired in a lawsuit brought by Jeremy Rifkin.

  17. Bypass diode for a solar cell

    Science.gov (United States)

    Rim, Seung Bum; Kim, Taeseok; Smith, David D.; Cousins, Peter J.

    2012-03-13

    Bypass diodes for solar cells are described. In one embodiment, a bypass diode for a solar cell includes a substrate of the solar cell. A first conductive region is disposed above the substrate, the first conductive region of a first conductivity type. A second conductive region is disposed on the first conductive region, the second conductive region of a second conductivity type opposite the first conductivity type.

  18. COMPOUNDING PHARMACIES' POTENTIAL TO CREATE Graft Storage Solutions for Bypass Surgeries.

    Science.gov (United States)

    Guth, Michael A S

    2015-01-01

    Several studies have addressed the optimal storage conditions for vascular grafts during bypass surgery. These studies have repeatedly shown that placing vascular graft conduits in isotonic saline solutions, and to a lesser extent in heparinized autologous blood, leads to a profound decline in endothelial cell viability. Endothelial damage to vein grafts can occur at multiple points during a coronary artery bypass graft surgery procedure: graft harvesting, handling, flushing, storage, anastomosis, and arterialization (e.g., damage caused by exposure to arterial blood pressure). This damage to endothelial cells causes the release of pro-inflammatory chemical signals that trigger thrombosis, intimal hyperplasia, and accelerated graft atherosclerosis, all of which ultimately contribute to graft failure. Cardiothoracic surgeons performing coronary artery bypass graft surgery and vascular surgeons performing peripheral artery bypass graft surgery have attempted to overcome the damage to the vascular grafts by using buffers to maintain the physiological pH of the storage solution. However, the endothelial layers in the grafts would benefit from having proper oxygenation and antioxidants added to the storage solution. Compounding pharmacies can perform a vital role in ensuring the patency of the vascular grafts by creating compounded flushing and storage solutions that have an optimal mix of nitric oxide substrates, antioxidants, and other nutrients for the endothelium. Maintaining structural and functional viability of the endothelia in grafts by using an appropriate vessel storage medium would lead to improved long-term graft patency.

  19. An experimental study of nerve bypass graft

    Institute of Scientific and Technical Information of China (English)

    XU Jie; LI Xue-shi

    2008-01-01

    Objective: To study the use of a nerve "bypass" graft as a possible alternative to neurolysis or segmental resection with interposition grafting in the treatment of neuroma-in-continuity. Methods: A sciatic nerve crush injury model was established in the Sprague-Dawley rat by compression with a straight hemostatic forceps. Epineurial windows were created proximal and distal to the injury site. An 8-mm segment of radial nerve was harvested and coaptated to the sciatic nerve at the epineurial window sites proximal and distal to the compressed segment (bypass group). A sciatic nerve crush injury without bypass served as a control. Nerve conduction studies were performed over an 8-week period. Sciatic nerves were then harvested and studied under transmission electron microscopy. Myelinated axon counts were obtained. Results: Nerve conduction velocity was significantly faster in the bypass group than in the control group at 8 weeks (63.57 m/s±5.83 m/s vs. 54.88 m/s±4.79m/s, P<0.01). Myelinated axon counts in distal segments were found more in the experimental sciatic nerve than in the control sciatic nerve. Significant axonal growth was noted in the bypass nerve segment itself. Conclusion: Nerve bypass may serve to augment peripheral axonal growth while avoiding further loss of the native nerve.

  20. PRESSURE-RESISTANT VESSEL

    NARCIS (Netherlands)

    Beukers, A.; De Jong, T.

    1997-01-01

    Abstract of WO 9717570 (A1) The invention is directed to a wheel-shaped pressure-resistant vessel for gaseous, liquid or liquefied material having a substantially rigid shape, said vessel comprising a substantially continuous shell of a fiber-reinforced resin having a central opening, an inner l

  1. Resolution of bilateral moyamoya associated collateral vessel aneurysms: Rationale for endovascular versus surgical intervention

    Directory of Open Access Journals (Sweden)

    Sepideh Amin-Hanjani

    2014-01-01

    Full Text Available Background: Management of aneurysms associated with deep collateral vessels in moyamoya disease is challenging both from an endovascular and a surgical standpoint. Difficulties with access or localization, and compromise of the collateral circulation with subsequent ischemia are the primary concerns, making direct obliteration potentially unfeasible or risky. Alternatively, superficial temporal artery-middle cerebral artery bypass is another potential strategy for resolution of these aneurysms. Case Description: Presented are the findings and management for a patient with moyamoya disease and bilateral deep collateral vessel aneurysms, successfully treated with endovascular obliteration following a right-sided hemorrhage and subsequently with bypass for an unruptured but growing contralateral aneurysm. Conclusions: A rationale and approach to management is outlined, as derived from review of the current literature and the illustrative case with bilateral collateral vessel aneurysms.

  2. Silver Nitrate and Different Culture Vessels Influence High Frequency Microrhizome Induction In Vitro and Enhancement Growth of Turmeric Plantlet During Ex Vitro Acclimatization

    Directory of Open Access Journals (Sweden)

    Dikash Singh THINGBAIJAM

    2012-11-01

    Full Text Available Eleven cultivars of C. longa var. Lakadong were collected from Manipur having different topography. Curcumin content in different cultivars has been analyzed by using UV-Visible Spectrophotometer (100 Bio-Carry Spectrophotometer. The curcuminoids content were analyzed and quantified for identification of best quality cultivar. Thoubal Cultivar with highest curcumin content (9.44% was subjected for tissue culture technique using different culture vessels and silver nitrate for rapid multiplication and scaling up of microrhizome production. High multiplication rate of 27.40�0.47 were obtained in Murashige and Skoog�s medium supplemented with 3% sucrose + 1 mg L-1 ?-napthalene acetic acid, 4 mg L-1 6-benzyl-amino-purine and 11 ?M silver nitrate. Effect of different culture vessels and silver nitrate were studied for microrhizome and multiple shoots formation. Relatively higher rate of shoots along with microrhizome (17.5�0.32 can be seen in Growtek which was grown without any plant growth regulator. Growtek was used for scaling up of microrhizome production in vitro and utmost microrhizome was produced in liquid Murashige and Skoog�s medium supplemented with 8% sucrose, 1 mg L-1 ?-napthalene acetic acid, 4 mg L-1 6-benzyl-amino-purine and 11 ?M silver nitrate (36.25�0.27. Addition of silver nitrate in the medium resulted in improvement of microrhizome induction in vitro. Higher concentration of silver nitrate (33, 44, 66, 88 ?M negatively affected the microrhizome and shoot multiplication and shows inhibition of tissue response completely. Analysis of in vitro derived plantlets during acclimatization shows that the exogenous applied of silver nitrate shows superior growth as compared to control. 90-95% of plantlets with and 75-80% plantlets without silver nitrate treatment were successfully established under ex vitro acclimatization. The protocol could be utilized for large scale production of true-to-type plantlets and as alternative

  3. Coronary flow reserve evaluated by {sup 201}Tl myocardial perfusion SPECT after coronary artery bypass grafting (CABG) for angina pectoris

    Energy Technology Data Exchange (ETDEWEB)

    Ishino, Yoichi; Nakata, Hajime [Univ. of Occupational and Environmental Health, Kitakyusyu, Fukuoka (Japan)

    2000-11-01

    We compared the flow reserves of the coronary bypass vessels between arterial and venous grafts by {sup 201}Tl myocardial perfusion SPECT on the patients with angina pectoris who had no past history of myocardial infarction or intervention therapy such as PTCA. Thirty two patients had undergone a total of 70 bypass grafts and 66 of them were proved to be patent at postoperative CAG. Reversible defects were observed in 6 of 40 segments (15.0%) covered by patent venous grafts, and in 11 of 26 segments (42.3%) by patent arterial grafts. The rate of postoperative reversible defects was higher in the areas grafted by artery but this had no relation with the severity of coronary artery stenosis before CABG. This reversible defect is most likely to be caused by the character of artery graft itself and this should not be considered to highly suggest the restenosis or occlusion of the graft vessel. (author)

  4. Effects of hypothermic cardiopulmonary bypass on the pharmacodynamics and pharmacokinetics of rocuronium

    NARCIS (Netherlands)

    Smeulers, NJ; Wierda, MKH; vandenBroek, L; Huet, RCGG; Hennis, PJ

    1995-01-01

    Objective: To study the influence of hypothermic cardiopulmonary bypass (CPB) on the pharmacodynamics and pharmacokinetics of rocuronium. Design: Prospective, descriptive study. Setting: Operating room at a university hospital. Participants: Ten ASA class III end IV patients, ranging in age from 35

  5. Low Incidence of Early Postoperative Cerebral Edema After Coronary Artery Bypass Grafting

    NARCIS (Netherlands)

    Ottens, Thomas H.; Hendrikse, J; Slooter, Arjen J. C.; van Herwerden, LA; Dieleman, Stefan; van Dijk, Diederik

    2015-01-01

    Objective: Using magnetic resonance imaging, the authors studied the influence of a single high dose of intraoperative dexamethasone on the severity of cerebral edema that can occur early after coronary artery bypass grafting (CABG). It was hypothesized that high-dose intraoperative dexamethasone re

  6. Mild preoperative renal dysfunction as a predictor of longterm clinical outcome after coronary bypass surgery

    NARCIS (Netherlands)

    van de Wal, RMA; van Brussel, BL; Voors, AA; Smilde, TDJ; van Swieten, HA; van Gilst, WH; van Veldhuisen, DJ; Plokker, HWT

    2005-01-01

    Renal dysfunction is a prognostic marker in patients with cardiovascular disease. However, no long-term follow-up studies on the influence of mild renal dysfunction on mortality in patients undergoing coronary bypass grafting have been reported. Therefore, we aimed to identify the significance of pr

  7. Confinement Vessel Dynamic Analysis

    Energy Technology Data Exchange (ETDEWEB)

    R. Robert Stevens; Stephen P. Rojas

    1999-08-01

    A series of hydrodynamic and structural analyses of a spherical confinement vessel has been performed. The analyses used a hydrodynamic code to estimate the dynamic blast pressures at the vessel's internal surfaces caused by the detonation of a mass of high explosive, then used those blast pressures as applied loads in an explicit finite element model to simulate the vessel's structural response. Numerous load cases were considered. Particular attention was paid to the bolted port connections and the O-ring pressure seals. The analysis methods and results are discussed, and comparisons to experimental results are made.

  8. Patency rates and the role of newer grafts in coronary artery bypass grafting.

    Science.gov (United States)

    Rai, Mridula; Rustagi, Tarun

    2013-10-01

    Coronary artery bypass grafting (CABG) was one of major surgical advances of the 20th century and it has proven to be one of the most effective and long-lasting therapies in the treatment of ischemic heart disease. Despite its success, the long-term outcome of coronary bypass surgery is strongly influenced by the fate of the vascular conduits used. We seek to review the emerging role and patency rates of newer arterial grafts in comparison with the traditional saphenous vein grafts.

  9. Non-invasive assessment of coronary artery bypass grafts - an update; Koronare Bypassdiagnostik mit CT und MRT - eine Bestandsaufnahme

    Energy Technology Data Exchange (ETDEWEB)

    Kreitner, K.F.; Ehrhard, K.; Kunz, R.P.; Oberholzer, K.; Mildenberger, P.; Thelen, M. [Klinik und Poliklinik fuer Radiologie der Johannes Gutenberg-Univ. Mainz (Germany); Abegunewardene, N.; Horstick, G. [2. Medizinische Klinik und Poliklinik der Johannes Gutenberg-Univ. Mainz (Germany); Hake, U. [Klinik und Poliklinik fuer Herz-Thorax- und Gefaesschirurgie der Johannes Gutenberg-Univ. Mainz (Germany)

    2004-08-01

    The limited lifetime and the correlation between graft occlusion and recurring symptoms underline the need for repeated imaging of coronary artery bypass grafts. CT and MRI allow for noninvasive imaging of coronary bypasses with high accuracies concerning the patency of these vessels. Multidetector CT seem to be the CT technique of choice, especially after the introduction of 16 slice CT scanners for morphologic assessment of coronary artery bypass grafts. Compared with MRI, CT is a robust technique for assessment of cardiac anastomoses, native coronary arteries, anf for the detection of graft stenoses. MRI, however, is able to deliver functional information about the grafts and the recipient coronary arteries by determining the coronary flow reserve. Furthermore, it can be integrated in a multiparametric MR examination protocol. The follow-up of asymptomatic patients can primarily be done by these non-invasive techniques as nearly every third patient reveals an asymptomatic bypass occlusion 5 years after operation. Furthermore, patients with atypical complaints after the operation may undergo non-invasive imaging as long as documented patency of the bypass averts coronary angiography. Patients with recurrent angina pectoris and/or myocardial ischemia discovered by other cardiologic tests have to undergo coronary angiography. (orig.)

  10. Fluid-structure Interaction Analysis of Coronary Artery Bypass Graft Based on the CT Images%基于CT成像的冠状动脉搭桥血管的流固耦合分析

    Institute of Scientific and Technical Information of China (English)

    刘赵淼; 高立丹; 史艺

    2013-01-01

    For the personalized reconstructed model of restenosis after coronary artery bypass graft,the influence of geometry model and elastic vessel wall on hemodynamic resuhing in restenosis is studied by using computational fluid dynamics.Based on the original CT data of coronary artery bypass graft from patients,the surface model of coronary artery bypass graft is constructed and vessel wall is generated,and the surface model of coronary artery bypass graft is constructed and vessel wall is generated in MIMICS.The coupled model of vessel wall and blood established,fluid-structure interaction based on the two-way is carried out in ANSYS Mechanical and CFX modules by using the finite element method.The wall shear stress and deformation of elastic wall and rigid wall are compared with in a given pulse pressure condition.Results show that the maximum wall shear stress and displacement of the personalized model are higher than those of the simplified CAD model,and locations of maximum displacements in both models are absolutely different.The maximum wall shear stress and displacement are lower than those of the rigid model.Simulation results provide more realistic reference data for diagnosis of restenosis after coronary artery bypass graft.%针对冠状动脉旁路再狭窄重建个性化血管模型,通过计算流体力学方法研究血管几何模型和弹性血管壁对血流动力学特性变化导致的冠脉搭桥血管再狭窄的影响.根据冠状动脉搭桥手术患者的原始CT数据,导入到MIMICS软件中构造出冠状动脉移植血管的三维表面模型,并生成血管壁NURBS曲面模型,进而建立血管壁/血液耦合模型,采用有限元方法在ANSYS Mechanical和CFX两个模块的基础上,通过专用的流固耦合算法实现弹性血管壁和血液的双向耦合计算,在给定脉冲压条件下模拟出弹性管壁和刚性壁面的壁剪应力分布和变形情况,并且进行比较.研究结果表明:个性化模型的最大壁面

  11. Cheboygan Vessel Base

    Data.gov (United States)

    Federal Laboratory Consortium — Cheboygan Vessel Base (CVB), located in Cheboygan, Michigan, is a field station of the USGS Great Lakes Science Center (GLSC). CVB was established by congressional...

  12. Maury Journals - US Vessels

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — U.S. vessels observations, after the 1853 Brussels Conference that set International Maritime Standards, modeled after Maury Marine Standard Observations.

  13. Coastal Logbook Survey (Vessels)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — This data set contains catch (landed catch) and effort for fishing trips made by vessels that have been issued a Federal permit for the Gulf of Mexico reef fish,...

  14. 2011 Vessel Density

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Automatic Identification Systems (AIS) are a navigation safety device that transmits and monitors the location and characteristics of many vessels in U.S. and...

  15. 2013 Vessel Density

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Automatic Identification Systems (AIS) are a navigation safety device that transmits and monitors the location and characteristics of many vessels in U.S. and...

  16. 2011 Cargo Vessel Density

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Automatic Identification Systems (AIS) are a navigation safety device that transmits and monitors the location and characteristics of many vessels in U.S. and...

  17. 2013 Cargo Vessel Density

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Automatic Identification Systems (AIS) are a navigation safety device that transmits and monitors the location and characteristics of many vessels in U.S. and...

  18. High Performance Marine Vessels

    CERN Document Server

    Yun, Liang

    2012-01-01

    High Performance Marine Vessels (HPMVs) range from the Fast Ferries to the latest high speed Navy Craft, including competition power boats and hydroplanes, hydrofoils, hovercraft, catamarans and other multi-hull craft. High Performance Marine Vessels covers the main concepts of HPMVs and discusses historical background, design features, services that have been successful and not so successful, and some sample data of the range of HPMVs to date. Included is a comparison of all HPMVs craft and the differences between them and descriptions of performance (hydrodynamics and aerodynamics). Readers will find a comprehensive overview of the design, development and building of HPMVs. In summary, this book: Focuses on technology at the aero-marine interface Covers the full range of high performance marine vessel concepts Explains the historical development of various HPMVs Discusses ferries, racing and pleasure craft, as well as utility and military missions High Performance Marine Vessels is an ideal book for student...

  19. 2013 Tanker Vessel Density

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Automatic Identification Systems (AIS) are a navigation safety device that transmits and monitors the location and characteristics of many vessels in U.S. and...

  20. 2013 Passenger Vessel Density

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Automatic Identification Systems (AIS) are a navigation safety device that transmits and monitors the location and characteristics of many vessels in U.S. and...

  1. 2013 Fishing Vessel Density

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Automatic Identification Systems (AIS) are a navigation safety device that transmits and monitors the location and characteristics of many vessels in U.S. and...

  2. Particles deposition induced by the magnetic field in the coronary bypass graft model

    Science.gov (United States)

    Bernad, Sandor I.; Totorean, Alin F.; Vekas, Ladislau

    2016-03-01

    Bypass graft failures is a complex process starting with intimal hyperplasia development which involve many hemodynamic and biological factors. This work presents experimental results regarding the possibility to use magnetic drug delivery to prevent the development of the intimal hyperplasia using a simplified but intuitive model. The primary goal is to understand the magnetic particle deposition in the anastomosis region of the bypass graft taking into account the complex flow field created in this area which involves recirculation region, flow mixing and presence of particles with high residence time. The three-dimensional geometry model was used to simulate the motion and accumulation of the particles under the magnetic field influence in anastomotic region of the coronary bypass graft. The flow patterns are evaluated both numerically and experimentally and show a good correlation in term of flow parameters like vortex length and flow stagnation point positions. Particle depositions are strongly dependent on the magnet position and consequently of the magnetic field intensity and field gradient. Increased magnetic field controlled by the magnet position induces increased particle depositions in the bypass graft anastomosis. The result shows that particle depositions depend on the bypass graft angle, and the deposition shape and particle accumulation respectively, depend by the flow pattern in the anastomosis region.

  3. Surgical treatment of brachiocephalic vessel involvement in Takayasu's arteritis

    Institute of Scientific and Technical Information of China (English)

    WU Xin; DUAN Hong-yong; GU Yong-quan; LI Jian-xin; CHEN Bing; WANG Zhong-gao; ZHANG Jian

    2010-01-01

    Background Takayasu's arteritis (TA) is a chronic idiopathic inflammatory disease that affects large and medium size arteries. The brachiocephalic trunk is the most frequently involved site in TA, and multi-vessel lesions are common. Surgical treatment includes vessel reconstruction surgery and percutaneous transluminal angioplasty (PTA). Herein, we report our preliminary experience with surgical treatment of cerebral ischemia caused by cervical arterial lesions due to TA.Methods From January 2000 to December 2007, 38 patients with cerebral ischemia caused by cervical arterial occlusive lesions due to TA were treated surgically. There were three males and 35 females, with an age range of 15-42 years (mean 26.5 years). All patients had operative repairs undertaken. Twenty eight patients received bypass operation and 10 patients received percutaneous transluminal angioplasty. One case with coronary stenosis received coronary artery bypass simultaneously. Patients were followed up for 11 months to eight years.Results There were no peri-operative deaths in cerebrovascular reconstruction patients. Symptoms of cerebral ischemia were improved or cured in 25 of 38 patients. There was a low incidence of cerebral reperfusion syndrome. Two patients died at five and seven years after surgery due to heart failure. Another 8 patients (20%) required further surgery for stenosis (5 patients) or anastomotic aneurysms (3 patients). Percutaneous transluminal angioplasty was performed successfully for treatment of aortic and renal lesions. Repeated angioplasty for revascularization was performed in six PTA cases with restenosis after 5-24 months.Conclusions When cerebral perfusion has potential to be affected by TA, a definitive corrective procedure is advised when the patient is relatively stable. Although the recurrence rate is very high, percutaneous transluminal angioplasty is the first choice procedure. Bypass operation is optimal for brachiocephalic-vessel involvement in TA

  4. Blood Vessel Tension Tester

    Science.gov (United States)

    1978-01-01

    In the photo, a medical researcher is using a specially designed laboratory apparatus for measuring blood vessel tension. It was designed by Langley Research Center as a service to researchers of Norfolk General Hospital and Eastern Virginia Medical School, Norfolk, Virginia. The investigators are studying how vascular smooth muscle-muscle in the walls of blood vessels-reacts to various stimulants, such as coffee, tea, alcohol or drugs. They sought help from Langley Research Center in devising a method of measuring the tension in blood vessel segments subjected to various stimuli. The task was complicated by the extremely small size of the specimens to be tested, blood vessel "loops" resembling small rubber bands, some only half a millimeter in diameter. Langley's Instrumentation Development Section responded with a miniaturized system whose key components are a "micropositioner" for stretching a length of blood vessel and a strain gage for measuring the smooth muscle tension developed. The micropositioner is a two-pronged holder. The loop of Mood vessel is hooked over the prongs and it is stretched by increasing the distance between the prongs in minute increments, fractions of a millimeter. At each increase, the tension developed is carefully measured. In some experiments, the holder and specimen are lowered into the test tubes shown, which contain a saline solution simulating body fluid; the effect of the compound on developed tension is then measured. The device has functioned well and the investigators say it has saved several months research time.

  5. LANL Robotic Vessel Scanning

    Energy Technology Data Exchange (ETDEWEB)

    Webber, Nels W. [Los Alamos National Lab. (LANL), Los Alamos, NM (United States)

    2015-11-25

    Los Alamos National Laboratory in J-1 DARHT Operations Group uses 6ft spherical vessels to contain hazardous materials produced in a hydrodynamic experiment. These contaminated vessels must be analyzed by means of a worker entering the vessel to locate, measure, and document every penetration mark on the vessel. If the worker can be replaced by a highly automated robotic system with a high precision scanner, it will eliminate the risks to the worker and provide management with an accurate 3D model of the vessel presenting the existing damage with the flexibility to manipulate the model for better and more in-depth assessment.The project was successful in meeting the primary goal of installing an automated system which scanned a 6ft vessel with an elapsed time of 45 minutes. This robotic system reduces the total time for the original scope of work by 75 minutes and results in excellent data accumulation and transmission to the 3D model imaging program.

  6. Heat recovery system to power an onboard NH{sub 3}-H{sub 2}O absorption refrigeration plant in trawler chiller fishing vessels

    Energy Technology Data Exchange (ETDEWEB)

    Fernandez-Seara, J.; Vales, A.; Vazquez, M. [Escuela Tecnica Superior de Ingenieros Industriales, Vigo (Spain). Area de Maquinas y Motores Termikcos

    1998-12-01

    This paper is concerned with the design, modelling and parametric analysis of a gas-to-thermal fluid heat recovery system from engine exhausts in a trawler chiller fishing vessel to power an NH{sub 3}-H{sub 2}O absorption refrigeration plant for onboard cooling production. Synthetic oil was used as heat transfer fluid and recirculated. The major components of the system are fluid-to-solution and gas-to-fluid heat exchangers. Both heat exchangers and the complete system have been modelled. Models are implemented in several computer programs. These models have been used to study the influence of geometric design parameters and thermal operating conditions on heat exchangers and system thermal performance. The analysis of the results allowed us to find the optimum thermal operating conditions that minimise total heat transfer area. Optimal design based on real data was performed and the operating function of exhaust gases by-pass control was obtained and is presented. (author)

  7. [Simplified laparoscopic gastric bypass. Initial experience].

    Science.gov (United States)

    Hernández-Miguelena, Luis; Maldonado-Vázquez, Angélica; Cortes-Romano, Pablo; Ríos-Cruz, Daniel; Marín-Domínguez, Raúl; Castillo-González, Armando

    2014-01-01

    Antecedentes: la cirugía de la obesidad comprende diversos procedimientos gastrointestinales. El bypass gástrico en Y de Roux es el prototipo de los procedimientos mixtos y el más practicado en el mundo en sus diversas variedades. Una técnica similar y novedosa es la adoptada por Cardoso-Ramos y Galvao denominada "bypass simplificado" que rápidamente se aceptó por la mayor facilidad y resultados muy parecidos a la técnica convencional. Objetivo: describir los resultados a un año del bypass gástrico simplificado para el tratamiento de la obesidad mórbida. Material y métodos: estudio retrospectivo y descriptivo de todos los pacientes a quienes se realizó bypass gástrico de enero de 2008 a julio de 2012, en la clínica de obesidad de un hospital privado de la Ciudad de México. Resultados: se estudiaron 90 pacientes con diagnóstico de obesidad mórbida, con límites de edad de 18 y 65 años, operados para bypass gástrico simplificado. En 10% de los pacientes hubo complicaciones, las más frecuentes fueron: hemorragia y hernia interna. Durante el periodo de estudio la mortalidad fue de 0%. La pérdida de peso promedio a los 12 meses fue de 72.7%. Conclusión: el bypass gástrico simplificado laparoscópico es una cirugía segura, con buenos resultados a mediano plazo, y con una pérdida del exceso de peso adecuada en 71% de los casos.

  8. Coronary artery bypass surgery in a patient with Kartagener syndrome: a case report and literature review

    Directory of Open Access Journals (Sweden)

    Bougioukas Ioannis

    2010-08-01

    Full Text Available Abstract Kartagener syndrome consists of congenital bronchiectasis, sinusitis, and total situs inversus in half of the patients. A patient diagnosed with Kartagener syndrome was reffered to our department due to 3-vessel coronary disease. An off-pump coronary artery bypass operation was performed using both internal thoracic arteries and a saphenous vein graft. We performed a literature review for cases with Kartagener syndrome, coronary surgery and dextrocardia. Although a few cases of dextrocardia were found in the literature, no case of Kartagener syndrome was mentioned.

  9. Coronary artery bypass surgery in a patient with Kartagener syndrome: a case report and literature review.

    Science.gov (United States)

    Bougioukas, Ioannis; Mikroulis, Dimitrios; Danner, Bernhard; Lawal, Lukman; Eleftheriadis, Savvas; Bougioukas, George; Didilis, Vassilios

    2010-08-26

    Kartagener syndrome consists of congenital bronchiectasis, sinusitis, and total situs inversus in half of the patients. A patient diagnosed with Kartagener syndrome was referred to our department due to 3-vessel coronary disease. An off-pump coronary artery bypass operation was performed using both internal thoracic arteries and a saphenous vein graft. We performed a literature review for cases with Kartagener syndrome, coronary surgery and dextrocardia. Although a few cases of dextrocardia were found in the literature, no case of Kartagener syndrome was mentioned.

  10. Analgesic Treatment in Laparoscopic Gastric Bypass Surgery

    DEFF Research Database (Denmark)

    Andersen, Lars P H; Werner, Mads U; Rosenberg, Jacob

    2014-01-01

    This review aimed to present an overview of the randomized controlled trials investigating analgesic regimens used in laparoscopic Roux-en-Y gastric bypass (LRYGB) surgery. Literature search was performed in PubMed and EMBASE databases in August 2013 in accordance to PRISMA guidelines. The litera......This review aimed to present an overview of the randomized controlled trials investigating analgesic regimens used in laparoscopic Roux-en-Y gastric bypass (LRYGB) surgery. Literature search was performed in PubMed and EMBASE databases in August 2013 in accordance to PRISMA guidelines...

  11. Doppler spectral characteristics of infrainguinal vein bypasses

    DEFF Research Database (Denmark)

    Nielsen, Tina G; von Jessen, F; Sillesen, H;

    1993-01-01

    With the aim of assessing the velocity profile of femoropopliteal and femorocrural vein bypasses, 128 patients undergoing infrainguinal vein bypass surgery entered a postoperative Duplex surveillance protocol, which included clinical assessment and Duplex scanning, using Doppler spectral analysis...... of arteriovenous fistulas the initially antegrade diastolic velocity was replaced by a retrograde flow within 3 months, whereas a forward flow in diastole was sustained in grafts with patent fistulas. Abnormal Duplex findings in 31 patients led to angiography and revision in 13 cases. Four revised grafts failed...

  12. Investigation on the Core Bypass Flow in a Very High Temperature Reactor

    Energy Technology Data Exchange (ETDEWEB)

    Hassan, Yassin

    2013-10-22

    Uncertainties associated with the core bypass flow are some of the key issues that directly influence the coolant mass flow distribution and magnitude, and thus the operational core temperature profiles, in the very high-temperature reactor (VHTR). Designers will attempt to configure the core geometry so the core cooling flow rate magnitude and distribution conform to the design values. The objective of this project is to study the bypass flow both experimentally and computationally. Researchers will develop experimental data using state-of-the-art particle image velocimetry in a small test facility. The team will attempt to obtain full field temperature distribution using racks of thermocouples. The experimental data are intended to benchmark computational fluid dynamics (CFD) codes by providing detailed information. These experimental data are urgently needed for validation of the CFD codes. The following are the project tasks: • Construct a small-scale bench-top experiment to resemble the bypass flow between the graphite blocks, varying parameters to address their impact on bypass flow. Wall roughness of the graphite block walls, spacing between the blocks, and temperature of the blocks are some of the parameters to be tested. • Perform CFD to evaluate pre- and post-test calculations and turbulence models, including sensitivity studies to achieve high accuracy. • Develop the state-of-the art large eddy simulation (LES) using appropriate subgrid modeling. • Develop models to be used in systems thermal hydraulics codes to account and estimate the bypass flows. These computer programs include, among others, RELAP3D, MELCOR, GAMMA, and GAS-NET. Actual core bypass flow rate may vary considerably from the design value. Although the uncertainty of the bypass flow rate is not known, some sources have stated that the bypass flow rates in the Fort St. Vrain reactor were between 8 and 25 percent of the total reactor mass flow rate. If bypass flow rates are on the

  13. Variable volume combustor with an air bypass system

    Energy Technology Data Exchange (ETDEWEB)

    Johnson, Thomas Edward; Ziminsky, Willy Steve; Ostebee, Heath Michael; Keener, Christopher Paul

    2017-02-07

    The present application provides a combustor for use with flow of fuel and a flow of air in a gas turbine engine. The combustor may include a number of micro-mixer fuel nozzles positioned within a liner and an air bypass system position about the liner. The air bypass system variably allows a bypass portion of the flow of air to bypass the micro-mixer fuel nozzles.

  14. 46 CFR 154.550 - Excess flow valve: Bypass.

    Science.gov (United States)

    2010-10-01

    ... 46 Shipping 5 2010-10-01 2010-10-01 false Excess flow valve: Bypass. 154.550 Section 154.550... and Process Piping Systems § 154.550 Excess flow valve: Bypass. If the excess flow valve allowed under § 154.532(b) has a bypass, the bypass must be of 1.0 mm (0.0394 in.) or less in diameter. Cargo Hose...

  15. Brief Analysis of Factors Influencing Installing of Reactor Pressure Vessel Stud on Site%浅析影响反应堆压力容器主螺栓现场安装的因素

    Institute of Scientific and Technical Information of China (English)

    胡大芬; 杨景超; 刘东杰; 陈莲

    2016-01-01

    Based on occurred CPR1000 reactor pressure vessel stud unscrewing in stud hole on site by u-sing multi stud tensioning machine(MSTM)in a domestic nuclear power plant,and combined the charac-teristics of its′stud screw thread structure and performance of MSTM,the influencing factors causing this phenomena were analyzed.The influencing mechanism of each factor was discussed.Then corresponding preventive measures were proposed.%针对国内某核电厂 CPR1000反应堆压力容器主螺栓采用整体螺栓拉伸机现场安装时无法顺利旋入主螺孔的现象,结合其主螺栓螺纹副结构和整体螺栓拉伸机性能特点,分析了造成该现象的影响因素,讨论了各因素的影响机理,并提出了相应的预防措施。

  16. 21 CFR 870.4240 - Cardiopulmonary bypass heat exchanger.

    Science.gov (United States)

    2010-04-01

    ... 21 Food and Drugs 8 2010-04-01 2010-04-01 false Cardiopulmonary bypass heat exchanger. 870.4240... bypass heat exchanger. (a) Identification. A cardiopulmonary bypass heat exchanger is a device, consisting of a heat exchange system used in extracorporeal circulation to warm or cool the blood...

  17. Obstructive and enteropathic syndromes after jejunoileal bypass surgery

    Energy Technology Data Exchange (ETDEWEB)

    Karasick, D.; Karasick, S.

    1981-05-15

    Small bowel bypass procedures for morbid obesity have been associated with many postoperative complications. With the use of the Scott procedure, the bypassed or excluded small bowel segment has recently been the focus of 2 syndromes - 'bypass enteritis' and 'defunctioned bowel syndrome'. We describe these postoperative complications and present their significant radiologic features.

  18. 21 CFR 870.3545 - Ventricular bypass (assist) device.

    Science.gov (United States)

    2010-04-01

    ... 21 Food and Drugs 8 2010-04-01 2010-04-01 false Ventricular bypass (assist) device. 870.3545... (CONTINUED) MEDICAL DEVICES CARDIOVASCULAR DEVICES Cardiovascular Prosthetic Devices § 870.3545 Ventricular bypass (assist) device. (a) Identification. A ventricular bypass (assist) device is a device that...

  19. 20 CFR 631.18 - Federal by-pass authority.

    Science.gov (United States)

    2010-04-01

    ... 20 Employees' Benefits 3 2010-04-01 2010-04-01 false Federal by-pass authority. 631.18 Section 631... Procedures § 631.18 Federal by-pass authority. (a) In the event that a State fails to submit a biennial State... Secretary's intent to exercise by-pass authority and an opportunity to request and to receive a...

  20. Numerical studies on the effects of hot end temperature on a single-stage multi-bypass type pulse tube cryocooler

    Science.gov (United States)

    Liu, S. X.; Chen, L. B.; Zhou, Y.; Wang, J. J.

    2015-12-01

    The performance of pulse tube cryocooler is affected by the temperature of hot end, which is mainly influenced by the temperature of environment. Effects on a single-stage multibypass type pulse tube cryocooler are investigated by means of numerical simulation. For different opening of multi-bypass orifices, the refrigeration performances are studied when hot end temperature changed in a certain range, and some numerical results are provided and analysed. Together with the temperature at cold head and multi-bypass position, the mass flow rate through the multi-bypass orifice is affected significantly by the temperature of hot end, and the optimum opening of multi-bypass orifice decreases with hot end temperature increasing from 240 K to 320 K. Therefore, to select an optimal opening of bypass orifice according to the temperature of operating environment is necessary.

  1. Growth of Intracranial Aneurysms Arised from Curved Vessels under the Influence of Elevated Wall Shear Stress ─ A Computer Simulation Study

    Science.gov (United States)

    Feng, Yixiang; Wada, Shigeo; Tsubota, Ken-Ichi; Yamaguchi, Takami

    Recent studies have suggested that long standing elevated wall shear stress might degenerate the arterial wall and be involved in the pathogenesis of intracranial aneurysm formation and development. The present study focuses on the interplay between the hemodynamic stresses, arterial wall degeneration and deformation. By constructing a computational model and examining the hypotheses that govern the rules to grow an intracranial aneurysm, we simulate the formation and development of intracranial aneurysms. The high wall shear stress is found to propagate towards the proximal and distal end of the formed aneurysm, which becomes the key factor for the expansion of wall degeneration and aneurysm progression. The development of aneurysm is influenced by the wall shear stress threshold, the Reynolds number and the rate of wall degeneration. Our preliminary results indicate that computer simulation can be used in the study of aneurysm mechanics and yields new insight into the mechanism of aneurysm pathophysiology.

  2. Bypassing BDD Construction for Reliability Analysis

    DEFF Research Database (Denmark)

    Williams, Poul Frederick; Nikolskaia, Macha; Rauzy, Antoine

    2000-01-01

    In this note, we propose a Boolean Expression Diagram (BED)-based algorithm to compute the minimal p-cuts of boolean reliability models such as fault trees. BEDs make it possible to bypass the Binary Decision Diagram (BDD) construction, which is the main cost of fault tree assessment....

  3. Gastric infarction following gastric bypass surgery

    Science.gov (United States)

    Do, Patrick H; Kang, Young S; Cahill, Peter

    2016-01-01

    Gastric infarction is an extremely rare occurrence owing to the stomach’s extensive vascular supply. We report an unusual case of gastric infarction following gastric bypass surgery. We describe the imaging findings and discuss possible causes of this condition. PMID:27200168

  4. Cephalic veins in coronary artery bypass surgery

    DEFF Research Database (Denmark)

    Licht, P; Jakobsen, Erik; Lerbjerg, G;

    1996-01-01

    Various alternative conduits for aortocoronary bypass grafting have been suggested when the saphenous vein quality is inadequate. During a 10-year period we have used the cephalic vein in 39 patients. Eighteen entered an angiographic follow-up study. A total of 31 arm vein grafts were used with 4...

  5. Post-Bypass Extensive Ascites due to Splanchnic Bypass and the Effectiveness of Hyperalimentation Treatment

    Directory of Open Access Journals (Sweden)

    Veysel Temizkan

    2013-04-01

    Full Text Available Reperfusion edema may develop in the early periods of chronic ischemic tissue reperfusion. Reperfusion edema may be represented after the splanchnic bypass with ascites, abdominal distension, and liver and kidney function impairment. In this article, we are reporting the hyperalimentation treatment and its results for the common ascites and hepatorenal syndrome, after a coeliac and superior mesenteric artery bypass. [Arch Clin Exp Surg 2013; 2(2.000: 124-128

  6. Off-pump and on-pump coronary artery bypass surgery:time to move on

    Institute of Scientific and Technical Information of China (English)

    Shahzad G Raja

    2004-01-01

    @@ To the editor: Chen and colleagues,1 and the editorial staff of the Chinese Medical Journal, deserve much credit for carrying out and publishing a prospective comparative study of on-pump and off-pump coronary artery bypass (OPCAB) surgery in 300 patients with triple-vessel coronary artery disease. Although this study is limited by non-randomization and selection bias yet contrary to the previously published prospective, randomized studies by Van Dijk et al,2 and Ascione et al,3 the patient population of this study is more representative of current coronary artery surgery practices. Even more important is the conclusion that OPCAB can be applied to patients with triple-vessel coronary artery disease and "in experienced hands" can achieve similar completeness of revascularization and similar early surgical results.

  7. Audiometric changes after coronary artery bypass graft

    Directory of Open Access Journals (Sweden)

    Khorsandi M T

    2007-09-01

    Full Text Available Background: Hearing is one of the most significant senses; There fore, any defect can be frightening. The incidence of sever hearing loss following coronary artery bypass surgery has been estimated as one per thousand. This Prospective study carried out to determine hearing effects of coronary artery bypass surgery."nMethods: age, audiometric changes before and after surgery (hearing levels at multiple frequencies, speech reception threshold and speech discrimination score, minimum blood pressure during the operation, and the time on bypass, measured on One hundred consecutive patients who candidate for coronary artery bypass surgery and the results analysed."nResults: One hundred patients completed the tests. Based on hearing changes found on pre- and post-operative tests, the patients were divided into 3 groups: Those with no change (47 patients according to their audiometric results; those with slight changes ≤10 db (43 patients; and those having average deficits of more than 10 db (10 patients. All the patients were male. None of the patients had complete or severe sensorineural hearing loss. The third group had more prolonged pumping duration when compared with the others groups (p=0.002. Furthermore, 90 percent of patients with a sensorineural hearing loss more than 10 db had diabetes mellitus and hyperlipidemia as risk factors."nConclusion: Sudden sensorineural hearing loss is a sequela in patients who undergoing coronary artery bypass surgery; however, it was usually mild and asymptomatic. Pumping time during the operation is a significant factor in occurring of this complication. With proper treatment of underlying diseases and eliminating the risk factors with improvement of our cardiopulmonary pumps we probably can get better hearing results.

  8. Anterior ischemic optic neuropathy after conventional coronary artery bypass graft surgery

    Science.gov (United States)

    Dorecka, Mariola; Miniewicz-Kurkowska, Joanna; Romaniuk, Dorota; Gajdzik-Gajdecka, Urszula; Wójcik-Niklewska, Bogumiła

    2011-01-01

    Summary Background Perioperative optic neuropathy is a disease which can lead to serious, irreversible damage of vision. This complication could be the result of non-ocular surgery, for example, cardiac or spinal procedures. We present a case of anterior ischemic neuropathy (AION) which occurred following a conventional coronary artery bypass graft procedure. Case Report A 57-year-old man, 4 days after Conventional Coronary Artery Bypass Graft surgery as result of multi-vessel stabile coronary artery disease and history of anterolateral wall myocardial infarction, was admitted to the Eye Clinic due to significant loss of vision in his right eye. The patient had hypertension and was a heavy smoker. On admission, the slit lamp examination revealed a relative afferent pupillary defect in the right eye. The fundus examination showed optic disc edema with the presence of flame hemorrhages. Best corrected visual acuity (BCVA) was 0.02. The results of eye examination and fluorescein angiography confirmed the diagnosis of AION. Anti-aggregation and antithrombotic treatment was continued with steroids and vasodilators. After 7 days of this treatment we noticed the improvement of BCVA to 0.2. At 6-month follow-up, the vision was stable, and fundus examination revealed optic disc atrophy. Conclusions After cardiac surgical operations, such as coronary artery bypass graft procedures, anterior ischemic optic neuropathy may occur. In those cases, close cooperation between the various specialists is necessary. PMID:21629193

  9. Application of Computational Physics: Blood Vessel Constrictions and Medical Infuses

    CERN Document Server

    Suprijadi,; Subekti, Petrus; Viridi, Sparisoma

    2013-01-01

    Application of computation in many fields are growing fast in last two decades. Increasing on computation performance helps researchers to understand natural phenomena in many fields of science and technology including in life sciences. Computational fluid dynamic is one of numerical methods which is very popular used to describe those phenomena. In this paper we propose moving particle semi-implicit (MPS) and molecular dynamics (MD) to describe different phenomena in blood vessel. The effect of increasing the blood pressure on vessel wall will be calculate using MD methods, while the two fluid blending dynamics will be discussed using MPS. Result from the first phenomenon shows that around 80% of constriction on blood vessel make blood vessel increase and will start to leak on vessel wall, while from the second phenomenon the result shows the visualization of two fluids mixture (drugs and blood) influenced by ratio of drugs debit to blood debit. Keywords: molecular dynamic, blood vessel, fluid dynamic, movin...

  10. Pressurized Vessel Slurry Pumping

    Energy Technology Data Exchange (ETDEWEB)

    Pound, C.R.

    2001-09-17

    This report summarizes testing of an alternate ''pressurized vessel slurry pumping'' apparatus. The principle is similar to rural domestic water systems and ''acid eggs'' used in chemical laboratories in that material is extruded by displacement with compressed air.

  11. Graywater Discharges from Vessels

    Science.gov (United States)

    2011-11-01

    addition, based on personal contact with the shipping company, storing graywater in ballast tanks while in port can limit vessel stability considering...enters the treatment system and mixes with the aerated liquid already in the aeration chamber. EPDM Air diffuser injects air near the bottom of the

  12. GOLD PRESSURE VESSEL SEAL

    Science.gov (United States)

    Smith, A.E.

    1963-11-26

    An improved seal between the piston and die member of a piston-cylinder type pressure vessel is presented. A layer of gold, of sufficient thickness to provide an interference fit between the piston and die member, is plated on the contacting surface of at least one of the members. (AEC)

  13. Very Versatile Vessel

    Science.gov (United States)

    2009-09-01

    data. This source provides information on aluminum hydrofoil vessels without the added weight of foil structures. The composite armor around the...to Powerboats. New York: International Marine/Ragged Mountain P, 2002. 8. [Asset/ Hydrofoil Advanced Surface Ship Evaluation Tool Module User Manual

  14. Vascular Patterns in Iguanas and Other Squamates: Blood Vessels and Sites of Thermal Exchange.

    Directory of Open Access Journals (Sweden)

    William Ruger Porter

    Full Text Available Squamates use the circulatory system to regulate body and head temperatures during both heating and cooling. The flexibility of this system, which possibly exceeds that of endotherms, offers a number of physiological mechanisms to gain or retain heat (e.g., increase peripheral blood flow and heart rate, cooling the head to prolong basking time for the body as well as to shed heat (modulate peripheral blood flow, expose sites of thermal exchange. Squamates also have the ability to establish and maintain the same head-to-body temperature differential that birds, crocodilians, and mammals demonstrate, but without a discrete rete or other vascular physiological device. Squamates offer important anatomical and phylogenetic evidence for the inference of the blood vessels of dinosaurs and other extinct archosaurs in that they shed light on the basal diapsid condition. Given this basal positioning, squamates likewise inform and constrain the range of physiological thermoregulatory mechanisms that may have been found in Dinosauria. Unfortunately, the literature on squamate vascular anatomy is limited. Cephalic vascular anatomy of green iguanas (Iguana iguana was investigated using a differential-contrast, dual-vascular injection (DCDVI technique and high-resolution X-ray microcomputed tomography (μCT. Blood vessels were digitally segmented to create a surface representation of vascular pathways. Known sites of thermal exchange, consisting of the oral, nasal, and orbital regions, were given special attention due to their role in brain and cephalic thermoregulation. Blood vessels to and from sites of thermal exchange were investigated to detect conserved vascular patterns and to assess their ability to deliver cooled blood to the dural venous sinuses. Arteries within sites of thermal exchange were found to deliver blood directly and through collateral pathways. The venous drainage was found to have multiple pathways that could influence neurosensory

  15. Vascular Patterns in Iguanas and Other Squamates: Blood Vessels and Sites of Thermal Exchange.

    Science.gov (United States)

    Porter, William Ruger; Witmer, Lawrence M

    2015-01-01

    Squamates use the circulatory system to regulate body and head temperatures during both heating and cooling. The flexibility of this system, which possibly exceeds that of endotherms, offers a number of physiological mechanisms to gain or retain heat (e.g., increase peripheral blood flow and heart rate, cooling the head to prolong basking time for the body) as well as to shed heat (modulate peripheral blood flow, expose sites of thermal exchange). Squamates also have the ability to establish and maintain the same head-to-body temperature differential that birds, crocodilians, and mammals demonstrate, but without a discrete rete or other vascular physiological device. Squamates offer important anatomical and phylogenetic evidence for the inference of the blood vessels of dinosaurs and other extinct archosaurs in that they shed light on the basal diapsid condition. Given this basal positioning, squamates likewise inform and constrain the range of physiological thermoregulatory mechanisms that may have been found in Dinosauria. Unfortunately, the literature on squamate vascular anatomy is limited. Cephalic vascular anatomy of green iguanas (Iguana iguana) was investigated using a differential-contrast, dual-vascular injection (DCDVI) technique and high-resolution X-ray microcomputed tomography (μCT). Blood vessels were digitally segmented to create a surface representation of vascular pathways. Known sites of thermal exchange, consisting of the oral, nasal, and orbital regions, were given special attention due to their role in brain and cephalic thermoregulation. Blood vessels to and from sites of thermal exchange were investigated to detect conserved vascular patterns and to assess their ability to deliver cooled blood to the dural venous sinuses. Arteries within sites of thermal exchange were found to deliver blood directly and through collateral pathways. The venous drainage was found to have multiple pathways that could influence neurosensory tissue temperature

  16. Wartime major venous vessel injuries.

    Science.gov (United States)

    Hudorovic, Narcis

    2008-02-01

    The aim of this study is to declare our experience and to identify the important factors that influence the mortality and morbidity in patients with combat-related penetrating wounds of the abdomen (CR-PWA) with major venous vessel injuries. Twenty-six wounded with combat-related injuries of major abdominal venous vessels, admitted in the University Clinic cardiovascular surgery department during the period from 1 August 1991 through 30 October 1995, were analyzed. Patients with concomitant injured arteries and extra-abdominal injuries (n=150; 85.2%) were excluded from this study. The Penetrating Abdominal Trauma Index (PATI) score for each patient was calculated. Fifteen patients (57.69%) sustained with PATI score greater than 25 died. The mean duration of hospitalization was 16 days (range 0-86). The average hospitalization time for those surviving their complications was 17 days with a PATI of 25 or less, and 43 days with a score more than 25. Three clinical assessments of the long-term outcome were performed after a median of about 3, 5 and 10 years, respectively. Surviving patients (42.31%) were symptom free and had normal Duplex scans as well as no other surgical related complications. Higher PATI scores, postoperative complications and reoperations exert an unfavorable effect on patient outcome.

  17. Combined Microencapsulated Islet Transplantation and Revascularization of Aortorenal Bypass in a Diabetic Nephropathy Rat Model

    Directory of Open Access Journals (Sweden)

    Yunqiang He

    2016-01-01

    Full Text Available Objective. Revascularization of aortorenal bypass is a preferred technique for renal artery stenosis (RAS in diabetic nephropathy (DN patients. Restenosis of graft vessels also should be considered in patients lacking good control of blood glucose. In this study, we explored a combined strategy to prevent the recurrence of RAS in the DN rat model. Methods. A model of DN was established by intraperitoneal injection of streptozotocin. Rats were divided into 4 groups: SR group, MIT group, Com group, and the untreated group. The levels of blood glucose and urine protein were measured, and changes in renal pathology were observed. The expression of monocyte chemoattractant protein-1 (MCP-1 in graft vessels was assessed by immunohistochemical staining. Histopathological staining was performed to assess the pathological changes of glomeruli and tubules. Results. The levels of urine protein and the expression of MCP-1 in graft vessels were decreased after islet transplantation. The injury of glomerular basement membrane and podocytes was significantly ameliorated. Conclusions. The combined strategy of revascularization and microencapsulated islet transplantation had multiple protective effects on diabetic nephropathy, including preventing atherosclerosis in the graft vessels and alleviating injury to the glomerular filtration barrier. This combined strategy may be helpful for DN patients with RAS.

  18. Intraoperative assessment of STA-MCA bypass patency using near-infrared indocyanine green video-angiography: A preliminary study

    Directory of Open Access Journals (Sweden)

    Sudheer Ambekar

    2012-01-01

    Full Text Available Background: Bypass patency is critical for patients undergoing superficial temporal artery-middle cerebral artery (STA-MCA anastomosis. Near-infrared indocyanine green video-angiography (ICGA is an excellent method to assess vessels during cerebrovascular surgery. Objective: The aim of the present study is to analyze the effectiveness of ICGA in patients undergoing STA-MCA anastomosis for moyamoya disease. Materials and Methods: This study was a retrospective review of case records and operation records of patients who underwent STA-MCA bypass for moyamoya disease at our institute. Concordance of ICGA with intraoperative micro-Doppler and postoperative angiography, whenever available, was assessed. Results: In all, 22 STA-MCA anastomoses were performed in 13 patients. ICGA was used to assess patency in 14 surgeries (10 patients. No patient required revision of anastomosis following ICGA. Postoperative angiography was done in five anastomoses (three patients at three months follow-up and correlated well with ICGA findings in all cases. Conclusion: ICGA is an effective technique to assess bypass patency during cerebrovascular surgery. Routine use of ICGA in cerebral bypass surgery improves graft patency and minimizes complications due to graft occlusion.

  19. Power turbine bypass for improved compression braking

    Energy Technology Data Exchange (ETDEWEB)

    Brooks, R.M.; Lutz, T.P.; Stang, J.

    1992-06-09

    This patent describes a turbocompound engine having a power turbine bypass control. It comprises an internal combustion engine having a crankshaft, an intake manifold and an exhaust manifold; turbocharger means connected with the intake and exhaust manifolds for converting exhaust gas energy into mechanical energy for boosting intake air pressure; power turbine means for producing mechanical energy from energy remaining in the exhaust gases exiting the first turbine.

  20. Coronary artery bypass grafting for Kawasaki disease

    Institute of Scientific and Technical Information of China (English)

    GUO Hong-wei; CHANG Qian; XU Jian-ping; SONG Yun-hu; SUN Han-song; HU Sheng-shou

    2010-01-01

    Background Kawasaki disease (KD) is the leading cause of pediatric ischemic heart disease. The incidence of serious coronary sequelae is low and about 2%-3% of patients with KD, but once myocardial infarction occurs in children, the mortality is quite high and 22% at the first infarction.This study aimed to evaluate the efficacy of coronary artery bypass grafting (CABG) in patients with KD.Methods Eight patients with a history of KD underwent CABG between October 1997 and July 2005. The number of bypass grafts placed was 2 to 4 per patient (mean 2.5±0.8). Various bypass grafts were used in patients, i.e. the left internal mammary artery (LIMA) in 3 patients, bilateral internal mammary artery (IMA) in 2 patients, LIMA plus gastroepiploic artery (GEA) in 1 patient and total saphenous vein grafts (SVGs) in 2 patients. The combined procedures included ventricular aneurysmectomy in 1 patient, mitral valve plasty in 1 and right coronary aneurysmectomy in 1. One patient was not able to wean from cardiopulmonary bypass (CPB), after being supported with intra-aortic balloon pump (IABP), the patient was weaned from CPB successfully.Results One patient died of low cardiac output syndrome and acute renal failure 19 days after operation. Other patients recovered and were discharged uneventfully. During the follow-up that ranged from 3 to 57 months (mean 27 months),clincal angina disappeared or improved. Cardiac function was in Class Ⅰ-Ⅱ (NYHA).Conclusion CABG is a safe and effective procedure for Kawasaki coronary artery disease. However long-term results need to be followed up.

  1. Bypass systems for shared outlets. Bypass-systemen voor gemeenschappelijke afvoersystemen

    Energy Technology Data Exchange (ETDEWEB)

    Dijkhof, W.; Huijzer, E.L.; Beltman, H.A.

    1993-05-01

    In stacked buildings large pressure differences can occur when appliances with individual air supply pipes are connected to a communal outlet. This can be prevented by using a so-called bypass system, which couples the air supply pipe directly to the combustion gases outlet. In case of overpressure on the air supply of an appliance, air will be transported to the combustion gases outlet around the appliance. Descriptions are given of two GASTEC-developed indoor systems: a mechanical bypass system and an aerodynamic bypass system. The aerodynamic system has been optimized for a retrofitting boiler project in Assen, Netherlands. In this project a communal heating system has been replaced by individual central heating boilers. The appliance used was a high-efficiency boiler, the NEFIT Turbo 21. The disadvantage of the mechanical bypass system is one of the moving parts: the valve, which is too sensitive for pollution and failures. Large pressure difference reductions are possible by means of the aerodynamic bypass system. Recirculation can be prevented by high-speed injection of the combustion gases in the combustion gases outlet. 13 figs., 26 tabs., 2 appendices, 2 refs.

  2. Hawaii Abandoned Vessel Inventory, Maui

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — NOAA Abandoned Vessel Project Data for Maui. Abandoned vessels pose a significant threat to the NOAA Trust resources through physical destruction of coral habitats...

  3. Hawaii Abandoned Vessel Inventory, Oahu

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — NOAA Abandoned Vessel Project Data for Oahu, Hawaii. Abandoned vessels pose a significant threat to the NOAA Trust resources through physical destruction of coral...

  4. CNMI Abandoned Vessel Inventory, Rota

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — NOAA Abandoned Vessel Project Data for Rota. Abandoned vessels pose a significant threat to the NOAA Trust resources through physical destruction of coral habitats...

  5. CNMI Abandoned Vessel Inventory, Tinian

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — NOAA Abandoned Vessel Project Data for Tinian. Abandoned vessels pose a significant threat to the NOAA Trust resources through physical destruction of coral habitats...

  6. CNMI Abandoned Vessel Inventory, Saipan

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — NOAA Abandoned Vessel Project Data for Saipan. Abandoned vessels pose a significant threat to the NOAA Trust resources through physical destruction of coral habitats...

  7. Hawaii Abandoned Vessel Inventory, Kauai

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — NOAA Abandoned Vessel Project Data for Kauai. Abandoned vessels pose a significant threat to the NOAA Trust resources through physical destruction of coral habitats...

  8. Hawaii Abandoned Vessel Inventory, Molokai

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — NOAA Abandoned Vessel Project Data for Molokai, Hawaii. Abandoned vessels pose a significant threat to the NOAA Trust resources through physical destruction of coral...

  9. American Samoa Abandoned Vessel Inventory

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — NOAA Abandoned Vessel Project Data for American Samoa. Abandoned vessels pose a significant threat to the NOAA Trust resources through physical destruction of coral...

  10. For-Hire Vessel Directory

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — The Vessel Directory is maintained as the sample frame for the For-Hire Survey. I contains data on for-hire vessels on the Atlantic and Gulf coasts. Data include...

  11. Puerto Rico Abandoned Vessel Inventory

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — NOAA Abandoned Vessel Project Data for Puerto Rico. Abandoned vessels pose a significant threat to the NOAA Trust resources through physical destruction of coral...

  12. Vessels in Transit - Web Tool

    Data.gov (United States)

    Department of Transportation — A web tool that provides real-time information on vessels transiting the Saint Lawrence Seaway. Visitors may sort by order of turn, vessel name, or last location in...

  13. Hawaii Abandoned Vessel Inventory, Lanai

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — NOAA Abandoned Vessel Project Data for Lanai. Abandoned vessels pose a significant threat to the NOAA Trust resources through physical destruction of coral habitats...

  14. Patient's Perception About Coronary Artery Bypass Grafting

    Directory of Open Access Journals (Sweden)

    Kelminda Maria Bulhões Mendonça

    2015-10-01

    Full Text Available ABSTRACT OBJECTIVE: The diagnosis of coronary artery disease referred for heart surgery has an important psychological component. The purpose of this study was to access the difficulties experienced by individuals awaiting coronary artery bypass grafting and to determine strategies that facilitate adaptation to a new lifestyle, modified by the disease. METHODS: A qualitative, exploratory study involving patients admitted to a university teaching hospital in the city of Salvador, Bahia, Brazil, awaiting coronary artery bypass grafting. Semi-structured interviews were performed in accordance with a previously defined script based on the study objective. Each transcription was read in its entirety to verify the representativeness, homogeneity and pertinence of the data obtained (pre-analysis, followed by separation of categories of analysis. RESULTS: The descriptions of this study show that patients admitted to the completion of coronary artery bypass grafting experience a wide range of psychological difficulties, considering that surgery acquires interpretations that vary according to individuals' subjectivity. The patients recognized the benefit of being able to discuss their feelings as a means of diminishing their fear and anxiety. CONCLUSION: Helping patients find resources to confront more positively the daily hospitalization is an important aspect for the health care professionals who assist them. This goal can be achieved through modification of the biomedical model of care for a biopsychosocial view. The investment of time and attention is of fundamental importance and aims to overcome existing deficiencies that interfere with the outcome of patients after cardiac surgery.

  15. Atypical complications of gastric bypass surgery

    Energy Technology Data Exchange (ETDEWEB)

    Mitchell, Myrosia T. [University of Chicago, Department of Radiology, 5841 S. Maryland Avenue, MC 2026, Chicago, IL 60637 (United States)]. E-mail: mmitchell@radiology.bsd.uchicago.edu; Pizzitola, Victor J. [University of Chicago, Department of Radiology, 5841 S. Maryland Avenue, MC 2026, Chicago, IL 60637 (United States); Knuttinen, M-Grace [University of Chicago, Department of Radiology, 5841 S. Maryland Avenue, MC 2026, Chicago, IL 60637 (United States); Robinson, Tiffany [University of Chicago, Department of Internal Medicine, 5841 S. Maryland Avenue, MC 2026, Chicago, IL 60637 (United States); Gasparaitis, Arunas E. [University of Chicago, Department of Radiology, 5841 S. Maryland Avenue, MC 2026, Chicago, IL 60637 (United States)

    2005-03-01

    Although gastric bypass surgery continues to grow in popularity for weight loss and weight maintenance in the morbidly obese, there has been little attention given to the imaging of complications associated with these surgeries. The purpose of our study is to demonstrate the variety of gastric bypass surgery complications that can be identified radiographically, with attention to the more unusual complications. This study was performed with institutional Internal Review Board approval. We performed a 5-year retrospective review of all patients who had undergone gastric bypass surgery, had complications of the surgery, and had studies performed in our department to image these complications. These studies consisted of contrast fluoroscopy and CT. We identified the more common complications of anastomotic stenoses and anastomotic leaks. We also identified six unusual complications as follow: (1) internal herniation through the small bowel mesentery, (2) internal herniation through the transverse mesocolon, (3) external herniation through the abdominal wall incision, (4) enterocutaneous fistulas, (5) antiperistaltic construction of the Roux-en-Y, and (6) incorrect anstomoses of the Roux limbs resulting in a Roux-en-O configuration. Our findings show that a thorough understanding of expected postoperative bowel configuration is essential in the evaluation of these patients. In addition, fluoroscopic evaluation should assess not only anatomy, but also motility.

  16. Hematological Disorders following Gastric Bypass Surgery: Emerging Concepts of the Interplay between Nutritional Deficiency and Inflammation

    Directory of Open Access Journals (Sweden)

    Mingyi Chen

    2013-01-01

    Full Text Available Obesity and the associated metabolic syndrome are among the most common and detrimental metabolic diseases of the modern era, affecting over 50% of the adult population in the United States. Surgeries designed to promote weight loss, known as bariatric surgery, typically involve a gastric bypass procedure and have shown high success rates for treating morbid obesity. However, following gastric bypass surgery, many patients develop chronic anemia, most commonly due to iron deficiency. Deficiencies of vitamins B1, B12, folate, A, K, D, and E and copper have also been reported after surgery. Copper deficiency can cause hematological abnormalities with or without neurological complications. Despite oral supplementation and normal serum concentrations of iron, copper, folate, and vitamin B12, some patients present with persistent anemia after surgery. The evaluation of hematologic disorders after gastric bypass surgery must take into account issues unique to the postsurgery setting that influence the development of anemia and other cytopenias. In this paper, the clinical characteristics and differential diagnosis of the hematological disorders associated with gastric bypass surgery are reviewed, and the underlying molecular mechanisms are discussed.

  17. Changes in Heart Rate Variability after Coronary Artery Bypass Grafting and Clinical Importance of These Findings.

    Science.gov (United States)

    Lakusic, Nenad; Mahovic, Darija; Kruzliak, Peter; Cerkez Habek, Jasna; Novak, Miroslav; Cerovec, Dusko

    2015-01-01

    Heart rate variability is a physiological feature indicating the influence of the autonomic nervous system on the heart rate. Association of the reduced heart rate variability due to myocardial infarction and the increased postinfarction mortality was first described more than thirty years ago. Many studies have unequivocally demonstrated that coronary artery bypass grafting surgery generally leads to significant reduction in heart rate variability, which is even more pronounced than after myocardial infarction. Pathophysiologically, however, the mechanisms of heart rate variability reduction associated with acute myocardial infarction and coronary artery bypass grafting are different. Generally, heart rate variability gradually recovers to the preoperative values within six months of the procedure. Unlike the reduced heart rate variability in patients having sustained myocardial infarction, a finding of reduced heart rate variability after coronary artery bypass surgery is not considered relevant in predicting mortality. Current knowledge about changes in heart rate variability in coronary patients and clinical relevance of such a finding in patients undergoing coronary artery bypass grafting are presented.

  18. Green Arctic Patrol Vessel

    Science.gov (United States)

    2010-10-01

    design with a full load displacement of 6,480 long tons. The vessel was outfitted with a towed sonary array, surface and air radar, and a small...and system complexity. 15. SUBJECT TERMS Arctic patrol, green technology, environment, polution , ship design, CISD, fuel cell 16. SECURITY...was outfitted with a towed sonary array, surface and air radar, and a small interdiction and rescue craft. In anticipation of more stringent

  19. Instability and "Sausage-String" Appearance in Blood Vessels during High Blood Pressure

    CERN Document Server

    Alstrøm, P; Colding-Jorgensen, M; Gustafsson, F; Holstein-Rathlou, N H; Alstrom, Preben; Eguiluz, Victor M.; Colding-Jorgensen, Morten; Gustafsson, Finn; Holstein-Rathlou, Niels-Henrik

    1999-01-01

    A new Rayleigh-type instability is proposed to explain the `sausage-string' pattern of alternating constrictions and dilatations formed in blood vessels under influence of a vasoconstricting agent. Our theory involves the nonlinear elasticity characteristics of the vessel wall, and provides predictions for the conditions under which the cylindrical form of a blood vessel becomes unstable.

  20. Study of transient turbine shot without bypass in a BWR; Estudio del transitorio disparo de turbina sin bypass en un BWR

    Energy Technology Data Exchange (ETDEWEB)

    Vallejo Q, J. A.; Martin del Campo M, C.; Fuentes M, L.; Francois L, J. L., E-mail: amhed_jvq@hotmail.com [UNAM, Facultad de Ingenieria, Departamento de Sistemas Energeticos, Ciudad Universitaria, 04510 Ciudad de Mexico (Mexico)

    2015-09-15

    The study and analysis of operational transients are important for predicting the behavior of a system to short-terms events and the impact that would cause this transition. For the nuclear industry these studies are indispensable due to economic, environmental and social impacts that could result in an accident during the operation of a nuclear reactor. In this paper the preparation, simulation and analysis of results of a turbine shot transient, which is not taken into operation the bypass is presented. The study is realized for a BWR of 2027 MWt, to an intermediate cycle life and using the computer code Simulate-3K a depressurization stage of the vessel is created which shows the response of other security systems and gives a coherent prediction to the event presented type. (Author)

  1. Dynamic Experimental Study of a Multi—bypass Pulse Tube Refrigerator with Two—bypass Tubes

    Institute of Scientific and Technical Information of China (English)

    YonglinJu; ChaoWang; 等

    1998-01-01

    A dynamic experimental apparatus to measure the instantaneous velocity and pressure in the multibypass pulse tube refrigerator(MPTR) was designed and constructed.Some important experimental results of the instantaneous measurements of the velocity and the pressure in the MPTR with twobypass tubes during actual operation are prsented.The effects of the middle-bypass version on the dynamic pressure and mass flow rate at the cold end of the pulse tube are ev aluated from experimental measurements.DC-flow phenomena are observed in this MPTR.The reasons of the multi-bypass version improved the performance of pulse tube refrigertor are given.

  2. One-week postoperative patency of lower extremity in situ bypass graft comparing epidural and general anesthesia

    DEFF Research Database (Denmark)

    Wiis, Julie Therese; Jensen-Gadegaard, Peter; Altintas, Ümit

    2014-01-01

    BACKGROUND: The purpose of this study was to determine whether anesthesia affects graft patency after lower extremity arterial in situ bypass surgery. METHODS: This investigation was a retrospective study using a national database on vascular surgical patients at a single medical institution. We...... under epidural (n = 386) or general (n = 499) anesthesia. Thirty-day mortality (3.4% for epidural anesthesia versus 4.4% general anesthesia; P = 0.414) and comorbidity were comparable in the 2 groups. Graft occlusion within 7 days after surgery was reported in 93 patients, with a similar incidence...... in the epidural (10.1%) and general (10.8%) anesthesia groups (P = 0.730). When examining a subgroup of patients (n = 242) exposed to surgery on smaller vessels (femorodistal in situ bypass procedures, n = 253), the incidence of graft occlusion was also similar in the 2 groups at 14.0% and 9.4%, respectively (P...

  3. A marked increase in gastric fluid volume during cardiopulmonary bypass

    OpenAIRE

    2011-01-01

    Major physiological stress occurs during cardiac surgery with cardiopulmonary bypass. This is related to hypothermia and artificial organ perfusion. Thus, serious gastrointestinal complications, particularly upper gastrointestinal bleeding, sometimes follow cardiac surgery. We have compared the antisecretory effects of a preanesthetic H2 antagonist (roxatidine, cardiopulmonary bypass-H2 group, n = 15) and a proton pump inhibitor (rabeprazole, cardiopulmonary bypass-PPI group, n = 15) in patie...

  4. Endovascular exclusion of aortoesophageal fistula after coarctation extraanatomical bypass.

    Science.gov (United States)

    Myers, Patrick O; Gemayel, Gino; Mugnai, Damiano; Murith, Nicolas; Kalangos, Afksendiyos

    2014-07-01

    Extraanatomical bypass has been advocated as the primary technique in adolescents or adults presenting with aortic coarctation. This approach carries significant morbidity, and graft-related complications may be more important in the young patient population. A 52-year-old man who had previously undergone extraanatomical bypass of aortic coarctation was diagnosed with a distal anastomotic pseudoaneurysm and aortoesophageal fistula. This was managed by proximal bypass plugging with an occluder, endovascular exclusion with a stent-graft in the thoracic descending aorta covering the pseudoaneurysm, and coarctation balloon dilation. Aortoesophageal fistula is a late complication observed after extraanatomical bypass for coarctation. This case illustrates this rare complication.

  5. Hormonal and metabolic responses of fetal lamb during cardiopulmonary bypass

    Institute of Scientific and Technical Information of China (English)

    苏肇伉; 周成斌; 张海波; 祝忠群

    2003-01-01

    Objective To study the hormonal and metabolic responses of fetal lamb during cardiopulmonary bypass.Methods Six pregnant ewes underwent fetal cardiopulmonary bypasses with artificial oxygenators and roller pumps for 30 minutes, which maintained the blood gas value at the fetal physiological level. The fetal blood pressure, heart rate, pH value and blood lactate levels were monitored. The levels of catecholamine, cortisol and insulin were measured pre-bypass and then again 30 minutes later. The blood glucose and free fatty acid levels were monitored continuously during the bypass. Fetal hepatic PAS staining was also carried out.Results There were no changes before and during the bypass in fetal blood pressure, heart rate and blood gas. However, pH values decreased and blood lactate levels increased (P<0.05). The fetal catecholamine and cortisol levels increased significantly (P<0.01), while the levels of insulin did not change. The blood glucose and free fatty acid levels increased at the beginning of the bypass (P<0.01), and then gradually slowed down during the bypass. The fetal hepatic PAS staining showed that hepatic glycogen was consumed in large amounts. After 30 minutes of bypass, the fetal lamb would not survive more than 1 hour.Conclusion The fetal lamb has a strong negative reaction to cardiopulmonary bypass.

  6. Attachment anxiety predicts poor adherence to dietary recommendations : an indirect effect on weight change 1 year after gastric bypass surgery

    NARCIS (Netherlands)

    Hinnen, C.; Aarts, F.; Geenen, R.

    2014-01-01

    BACKGROUND: Weight loss after gastric bypass surgery depends on the adoption of healthy dietary recommendations, which may be influenced by psychological issues and patients' attachment representations (habitual states of mind with respect to interpersonal relations). The present study tests (1) whe

  7. Attachment Anxiety Predicts Poor Adherence to Dietary Recommendations : an Indirect Effect on Weight Change 1 Year After Gastric Bypass Surgery

    NARCIS (Netherlands)

    Aarts, Floor; Geenen, Rinie; Gerdes, Victor E. A.; van de Laar, Arnold; Brandjes, Dees P. M.; Hinnen, Chris

    2015-01-01

    Weight loss after gastric bypass surgery depends on the adoption of healthy dietary recommendations, which may be influenced by psychological issues and patients' attachment representations (habitual states of mind with respect to interpersonal relations). The present study tests (1) whether attachm

  8. Attachment anxiety predicts poor adherence to dietary recommendations : an indirect effect on weight change one year after gastric bypass surgery

    NARCIS (Netherlands)

    Aarts, F.; Geenen, R.; Gerdes, V.E.A.; Van de Laar, A., A.; Brandjes, D.P.M.; Hinnen, C.

    2015-01-01

    BACKGROUND: Weight loss after gastric bypass surgery depends on the adoption of healthy dietary recommendations, which may be influenced by psychological issues and patients' attachment representations (habitual states of mind with respect to interpersonal relations). The present study tests (1) whe

  9. On streak breakdown in bypass transition

    Science.gov (United States)

    Schlatter, Philipp; Brandt, Luca; de Lange, H. C.; Henningson, Dan S.

    2008-10-01

    Recent theoretical, numerical, and experimental investigations performed at the Department of Mechanics, KTH Stockholm, and the Department of Mechanical Engineering, Eindhoven University of Technology, are reviewed, and new material is presented to clarify the role of the boundary-layer streaks and their instability with respect to turbulent breakdown in bypass transition in a boundary layer subject to free-stream turbulence. The importance of the streak secondary-instability process for the generation of turbulent spots is clearly shown. The secondary instability manifests itself as a growing wave packet located on the low-speed streak, increasing in amplitude as it is dispersing in the streamwise direction. In particular, qualitative and quantitative data pertaining to temporal sinuous secondary instability of a steady streak, impulse responses both on a parallel and a spatially developing streak, a model problem of bypass transition, and full simulations and experiments of bypass transition itself are collected and compared. In all the flow cases considered, similar characteristics in terms of not only growth rates, group velocity, and wavelengths but also three-dimensional visualizations of the streak breakdown have been found. The wavelength of the instability is about an order of magnitude larger than the local boundary-layer displacement thickness δ∗, the group velocity about 0.8 of the free-stream velocity U∞, and the growth rate on the order of a few percent of U∞/δ∗. The characteristic structures at the breakdown are quasistreamwise vortices, located on the flanks of the low-speed region arranged in a staggered pattern.

  10. Vessel enhancing diffusion: a scale space representation of vessel structures.

    Science.gov (United States)

    Manniesing, Rashindra; Viergever, Max A; Niessen, Wiro J

    2006-12-01

    A method is proposed to enhance vascular structures within the framework of scale space theory. We combine a smooth vessel filter which is based on a geometrical analysis of the Hessian's eigensystem, with a non-linear anisotropic diffusion scheme. The amount and orientation of diffusion depend on the local vessel likeliness. Vessel enhancing diffusion (VED) is applied to patient and phantom data and compared to linear, regularized Perona-Malik, edge and coherence enhancing diffusion. The method performs better than most of the existing techniques in visualizing vessels with varying radii and in enhancing vessel appearance. A diameter study on phantom data shows that VED least affects the accuracy of diameter measurements. It is shown that using VED as a preprocessing step improves level set based segmentation of the cerebral vasculature, in particular segmentation of the smaller vessels of the vasculature.

  11. Work on the Geneva motorway bypass

    CERN Multimedia

    État de Genève, DCTI, Direction du génie civil

    2006-01-01

    Work on the airport section of the Geneva motorway bypass is continuing and will require the temporary closure of two sliproads allowing traffic to make a U-turn near the airport and the Palexpo exhibition centre. The sliproads on the French and Lausanne sides will be closed until autumn 2006. U-turns will still be possible via clearly marked deviations. For further information: www.autoroute-aeroport.ch We would like to thank you in advance for your understanding. Civil Engineering Department, DCTI, State of Geneva

  12. Bypass variants of Zgornji Hotič

    OpenAIRE

    Vozelj, Nejc

    2014-01-01

    In my Graduation Thesis we presented the solution of road through Zgornji Hotič. This road si daily very busy, because the road is the main connection between the capital of Slovenia and the region Zasavje. The discussed road through Zgornji Hotič is problematic because of dangerous sections of the road and nearby buildings, which lower the transportability and safety of the road. As a solution we have decided to make a bypass between the south-end of Zgornji Hotič and the river Sava. We have...

  13. Hemodynamics Simulation of Stenosed Coronary Bypass Graft

    Institute of Scientific and Technical Information of China (English)

    LIU You-jun; QIAO Aike; DU Jian-jun

    2005-01-01

    By means of FEM, the physiological blood flow in coronary bypass graft is simulated. The stenosis in coronary artery is involved in the graft model,and the deformation of graft end to allow the surgical suture with a smaller diameter coronary is taken into consideration. The flow pattern, secondary flow and wall shear stress in the vicinity of anastomosis are analyzed. It is shown that a zone of low wall stress and high wall stress gradient exists downstream the toe. The floor opposed to the anastomosis is an area of high wall stress and high wall stress gradient. Both the toe downstream and the anastomosis bottom floor are prone to intimal hyperplasia.

  14. TRAS principles blight arterial bypass and plasty.

    Directory of Open Access Journals (Sweden)

    Kothari M

    1997-04-01

    Full Text Available A new concept--Tissue Requisitions (Principle I/Relinquishes (Principle II Arterial Supply--of TRAS principles is introduced to help appreciate the failures/successes of modern medicine′s attempts at restoring arterial flow in luminally compromised coronary/carotid fields, an invasive branch rightly called vascular ReRheology, which comprises diagnosing/treating arterial blocks. The technical wizardry of arterial reconstruction (bypass or lumen--restoration (plasty has to reckon with the TRAS principles all the time.

  15. Vessel enhancing diffusion: a scale space representation of vessel

    OpenAIRE

    Manniesing, Rashindra; Viergever, M.A.; Niessen, Wiro

    2006-01-01

    textabstractA method is proposed to enhance vascular structures within the framework of scale space theory. We combine a smooth vessel filter which is based on a geometrical analysis of the Hessian's eigensystem, with a non-linear anisotropic diffusion scheme. The amount and orientation of diffusion depend on the local vessel likeliness. Vessel enhancing diffusion (VED) is applied to patient and phantom data and compared to linear, regularized Perona-Malik, edge and coherence enhancing diffus...

  16. Indications and Outcomes of Prophylactic and Therapeutic Extracranial-to-intracranial Arterial Bypass for Cerebral Revascularization

    Directory of Open Access Journals (Sweden)

    Emre Gazyakan, MD, MSc

    2015-04-01

    Conclusions: The collaboration of neurosurgeons and plastic surgeons in performing EC-IC bypass can result in excellent outcomes with a high bypass patency rate and few complications, particularly for prophylactic EC-IC bypass.

  17. Image guidance for robotic minimally invasive coronary artery bypass.

    Science.gov (United States)

    Figl, Michael; Rueckert, Daniel; Hawkes, David; Casula, Roberto; Hu, Mingxing; Pedro, Ose; Zhang, Dong Ping; Penney, Graeme; Bello, Fernando; Edwards, Philip

    2010-01-01

    A novel system for image guidance in totally endoscopic coronary artery bypass (TECAB) is presented. Key requirement is the availability of 2D-3D registration techniques that can deal with non-rigid motion and deformation. Image guidance for TECAB is mainly required before the mechanical stabilisation of the heart, when the most dominant source of misregistration is the deformation and non-rigid motion of the heart. To augment the images in the endoscope of the da Vinci robot, we have to find the transformation from the coordinate system of the preoperative imaging modality to the system of the endoscopic cameras. In a first step we build a 4D motion model of the beating heart. Intraoperatively we can use the ECG or video processing to determine the phase of the cardiac cycle, as well as the heart and respiratory frequencies. We then take the heart surface from the motion model and register it to the stereo endoscopic images of the da Vinci robot resp. of a validation system using photo-consistency. To take advantage of the fact that there is a whole image sequence available for registration, we use the different phases together to get the registration. We found the similarity function to be much smoother when using more phases. This also showed promising behaviour in convergence tests. Images of the vessels available in the preoperative coordinate system can then be transformed to the camera system and projected into the calibrated endoscope view using two video mixers with chroma keying. It is hoped that the augmented view can improve the efficiency of TECAB surgery and reduce the conversion rate to more conventional procedures.

  18. Heritability of retinal vessel diameters and blood pressure

    DEFF Research Database (Denmark)

    Taarnhøj, Nina C B B; Larsen, Michael; Sander, Birgit

    2006-01-01

    PURPOSE: To assess the relative influence of genetic and environmental effects on retinal vessel diameters and blood pressure in healthy adults, as well as the possible genetic connection between these two characteristics. METHODS: In 55 monozygotic and 50 dizygotic same-sex healthy twin pairs......%-80%) for CRAE, 83% (95% CI: 73%-89%) for CRVE, and 61% (95% CI: 44%-73%) for mean arterial blood pressure (MABP). Retinal artery diameter decreased with increasing age and increasing arterial blood pressure. Mean vessel diameters in the population were 165.8 +/- 14.9 microm for CRAE, 246.2 +/- 17.7 microm...... and blood glucose, variations in retinal blood vessel diameters and blood pressure were predominantly attributable to genetic effects. A genetic influence may have a role in individual susceptibility to hypertension and other vascular diseases. The results suggest that retinal vessel diameters...

  19. Cavitation distribution within large phantom vessel and mechanical damage formed on surrounding vessel wall.

    Science.gov (United States)

    Qiao, Yangzi; Yin, Hui; Li, Zhaopeng; Wan, Mingxi

    2013-11-01

    Blood vessel is one of the most important targets encountered during focused ultrasound (FU) therapy. The lasting high temperature caused by continuous FU can result in structural modification of small vessel. For the vessel with a diameter larger than 2mm, convective cooling can significantly weaken the thermal effect of FU. Meanwhile, the continued presence of ultrasound will cause repetitive cavitation and acoustic microstreaming, making comprehension of continuous wave induced cavitation effect in large vessels necessary. The Sonoluminescence (SL) method, mechanical damage observation and high-speed camera were used in this study to investigate the combination effect of ultrasound contrast agents (UCAs) and continuous FU in large phantom vessels with a diameter of 10mm without consideration of thermal effect. When the focus was positioned at the proximal wall, cylindrical hole along the acoustic axis opposite the ultrasound wave propagation direction was observed at the input power equal to or greater than 50 W. When the focus was located at the distal wall, only small tunnels can be found. The place where the cylindrical hole formed was corresponding to where bubbles gathered and emitted brilliant light near the wall. Without UCAs neither such bright SL nor cylindrical hole can be found. However, the UCAs concentration had little influence on the SL distribution and the length of cylindrical hole. The SL intensity near the proximal vessel wall and the length of the cylindrical hole both increased with the input power. It is suggested that these findings need to be considered in the large vessel therapy and UCAs usage.

  20. Hypoglycemic effect and influence on glucose tolerance and insulin resistance of gastric bypass operation on type 2 diabetes mellitus rats%胃转流术对2型糖尿病大鼠的降糖作用及对糖耐量和胰岛素抵抗的影响

    Institute of Scientific and Technical Information of China (English)

    张秀忠; 任泽强; 张蓬波

    2010-01-01

    目的 观察胃转流术(CBP)对2型糖尿病大鼠的降糖效果及对糖耐量和胰岛素抵抗的影响.方法 将健康雄性SD大鼠随机分为正常组(NO组,n=10)和造模组(n=32).成模大鼠随机分为糖尿病手术组(DO组)、假手术组(DS组)和对照组(DC组),每组8只.检测手术前后各组空腹血糖、胰岛素、口服葡萄糖30min后的血糖及胰岛素抵抗指数(HOMA-IR).检测DO组术前与术后第4周口服葡萄糖耐量实验后0、10、30、60、120、180 min血糖,计算糖耐量曲线下面积.结果DO组GBP术后第8周空腹血糖由术前的(17.80±2.26)mmol/L下降到(6.18±0.53)mmol/L(P<0.05),NO组手术前后空腹血糖无明显变化.口服葡萄糖30 min后血糖DO组下降更为明显,由术前的(29.20±1.46)mmol/L至术后第8周下降到(13.55±0.86)mmol/L(P<0.05).术后4周DO组各时间点OGTT曲线下面积(AUC)下降约40.1%.DO组术后8周HOMA-IR明显下降,由术前的9.36±0.90下降至4.03±0.34(P<0.05).结论 胃转流术能明显降低2型糖尿病大鼠的血糖水平,且能明显改善糖耐量和胰岛素抵抗,并对正常血糖值无影响.%Objective To observe the hypoglycemic effect and influence on glucose tolerance and insulin resistance of gastric bypass operation (GBP) on type 2 diabetes mellitus rats.Methods Healthy male SD rats were randomly divided into normal rats group ( n = 10) and model group ( n = 32 ).The type 2 diabetes mellitus rats model were randomly divided into three groups: type 2 diabetes-operation group ( DO group),type 2 diabetes-shame operation group ( DS group ) and type 2 diabetes-control group ( DC group); The normal rats group was normal-operation group ( NO group).There were 8 rats in each group.Plasma glucose concentration,insulin and homeostasis model of insulin resistance (HMOA-IR) were measured respectively at fasting condition and plasma glucose concentration was measured at post oral glucose 30 min condition in preoperation and postoperation.Blood glucose

  1. Previous gastric bypass surgery complicating total thyroidectomy.

    Science.gov (United States)

    Alfonso, Bianca; Jacobson, Adam S; Alon, Eran E; Via, Michael A

    2015-03-01

    Hypocalcemia is a well-known complication of total thyroidectomy. Patients who have previously undergone gastric bypass surgery may be at increased risk of hypocalcemia due to gastrointestinal malabsorption, secondary hyperparathyroidism, and an underlying vitamin D deficiency. We present the case of a 58-year-old woman who underwent a total thyroidectomy for the follicular variant of papillary thyroid carcinoma. Her history included Roux-en-Y gastric bypass surgery. Following the thyroid surgery, she developed postoperative hypocalcemia that required large doses of oral calcium carbonate (7.5 g/day), oral calcitriol (up to 4 μg/day), intravenous calcium gluconate (2.0 g/day), calcium citrate (2.0 g/day), and ergocalciferol (50,000 IU/day). Her serum calcium levels remained normal on this regimen after hospital discharge despite persistent hypoparathyroidism. Bariatric surgery patients who undergo thyroid surgery require aggressive supplementation to maintain normal serum calcium levels. Preoperative supplementation with calcium and vitamin D is strongly recommended.

  2. Rescue microsurgery with bypass and stent removal following Pipeline treatment of a giant internal carotid artery terminus aneurysm.

    Science.gov (United States)

    Bowers, Christian A; Taussky, Philip; Park, Min S; Neil, Jayson A; Couldwell, William T

    2015-12-01

    We report the microsurgical rescue and removal of a Pipeline stent embolization of a giant internal carotid artery terminus aneurysm. After the initial placement of a Pipeline Embolization Device (PED), it migrated proximally to the cavernous carotid with the distal end free in the middle of the aneurysm, resulting in only partial aneurysm neck coverage. The patient underwent microsurgical rescue with trapping, bypass, and opening of the aneurysm with PED removal. The vessel remained patent in the proximal segment previously covered by the Pipeline stent. Microsurgical rescue for definitive aneurysm treatment with PED removal can be safe and effective for aneurysms unsuccessfully treated with PED.

  3. Inadvertent Entrapment of a Central Venous Catheter by a Purse-String Suture during Cardiopulmonary Bypass: A Case Report

    Directory of Open Access Journals (Sweden)

    Abdorasoul Anvaripour

    2011-01-01

    Full Text Available A 65-year-old female patient with severe mitral valve stenosis plus coronary artery disease was scheduled for mitral valve replacement and 2-vessel coronary artery bypass graft (CABG surgeries simultaneously. After a successful procedure, resistance was met on a CVC withdrawal. During postoperative fluoroscopy, fixation of the catheter at the heart was confirmed which necessitated reopening the chest, cutting the suture, and removing the catheter. When a catheter became hard to withdraw after open heart surgery, we should never withdraw it forcefully and blindly. Although rare, one should consider inadvertent entrapment of CVC by a suture as the possible cause.

  4. The vessel fluence; Fluence cuve

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2001-07-01

    This book presents the proceedings of the technical meeting on the reactors vessels fluence. They are grouped in eight sessions: the industrial context and the stakes of the vessels control; the organization and the methodology for the fluence computation; the concerned physical properties; the reference computation methods; the fluence monitoring in an industrial context; vessels monitoring under irradiation; others methods in the world; the research and development programs. (A.L.B.)

  5. Haemodynamics during maximal exercise after coronary bypass surgery

    NARCIS (Netherlands)

    P.W.J.C. Serruys (Patrick); M.F. Rousseau (Francois); J. Cosyns; R. Ponlot; L.A. Brasseur; J-M.R. Detry (Jean-Marie)

    1978-01-01

    textabstractFifty patients underwent an objective measurement of physical working capacity by means of a multistage test of maximally tolerated exertion before and after coronary bypass surgery; 29 patients also had haemodynamic measurements during maximal exercise before and after coronary bypass s

  6. Renal tubular acidosis secondary to jejunoileal bypass for morbid obesity

    DEFF Research Database (Denmark)

    Schaffalitzky de Muckadell, O B; Ladefoged, Jens; Thorup, Jørgen Mogens

    1985-01-01

    Renal handling of acid and base was studied in patients with persistent metabolic acidosis 3-9 years after jejunoileal bypass for morbid obesity. Excretion of acid was studied before and after intravenous infusion of NH4Cl and excretion of bicarbonate after infusion of NaHCO3. Bypass patients...

  7. 20 CFR 631.38 - State by-pass authority.

    Science.gov (United States)

    2010-04-01

    ... 20 Employees' Benefits 3 2010-04-01 2010-04-01 false State by-pass authority. 631.38 Section 631.38 Employees' Benefits EMPLOYMENT AND TRAINING ADMINISTRATION, DEPARTMENT OF LABOR PROGRAMS UNDER TITLE III OF THE JOB TRAINING PARTNERSHIP ACT State Administration § 631.38 State by-pass authority....

  8. Lower leg electrical impedance after distal bypass surgery

    DEFF Research Database (Denmark)

    Belanger, G K; Bolbjerg, M L; Heegaard, N H;

    1998-01-01

    Electrical impedance was determined in 13 patients following distal bypass surgery to evaluate lower leg oedema as reflected by its circumference. Tissue injury was assessed by the plasma concentration of muscle enzymes. After surgery, the volume of the control lower leg increased from 1250 (816...... to be a useful method for the evaluation of lower leg oedema after distal bypass surgery....

  9. Diagnostic tools for post-gastric bypass hypoglycaemia

    NARCIS (Netherlands)

    Emous, M.; Ubels, F. L.; van Beek, A. P.

    2015-01-01

    In spite of its evident success, several late complications can occur after gastric bypass surgery. One of these is post-gastric bypass hypoglycaemia. No evidence-based guidelines exist in the literature on how to confirm the presence of this syndrome. This study aims to describe and compare the tes

  10. Sen perforation af tyndtarm efter laparoskopisk gastrisk bypass

    DEFF Research Database (Denmark)

    Spanager, Lene; Sigild, Ulf Henrik; Neuenschwander, Anders Ulrich

    2010-01-01

    We present two cases in which the patients were admitted to a local hospital with acute abdominal pain four or five months after having undergone laparoscopic gastric bypass. In both cases, operation revealed a perforation of the small bowel close to the distal anastomosis. In the first case...... bypass but as our two cases illustrate they are important to keep in mind....

  11. Dacron or PTFE for above-knee femoropopliteal bypass. a multicenter randomised study

    DEFF Research Database (Denmark)

    Jensen, L P; Lepäntalo, M; Fossdal, J E

    2007-01-01

    To compare polytetrafluorethylene (PTFE) and polyester grafts (Dacron) for above knee femoropopliteal bypass.......To compare polytetrafluorethylene (PTFE) and polyester grafts (Dacron) for above knee femoropopliteal bypass....

  12. Americium behaviour in plastic vessels

    Energy Technology Data Exchange (ETDEWEB)

    Legarda, F.; Herranz, M. [Departamento de Ingenieria Nuclear y Mecanica de Fluidos, Escuela Tecnica Superior de Ingenieria de Bilbao, Universidad del Pais Vasco (UPV/EHU), Alameda de Urquijo s/n, 48013 Bilbao (Spain); Idoeta, R., E-mail: raquel.idoeta@ehu.e [Departamento de Ingenieria Nuclear y Mecanica de Fluidos, Escuela Tecnica Superior de Ingenieria de Bilbao, Universidad del Pais Vasco (UPV/EHU), Alameda de Urquijo s/n, 48013 Bilbao (Spain); Abelairas, A. [Departamento de Ingenieria Nuclear y Mecanica de Fluidos, Escuela Tecnica Superior de Ingenieria de Bilbao, Universidad del Pais Vasco (UPV/EHU), Alameda de Urquijo s/n, 48013 Bilbao (Spain)

    2010-07-15

    The adsorption of {sup 241}Am dissolved in water in different plastic storage vessels was determined. Three different plastics were investigated with natural and distilled waters and the retention of {sup 241}Am by these plastics was studied. The same was done by varying vessel agitation time, vessel agitation speed, surface/volume ratio of water in the vessels and water pH. Adsorptions were measured to be between 0% and 70%. The adsorption of {sup 241}Am is minimized with no water agitation, with PET or PVC plastics, and by water acidification.

  13. Using SA508/533 for the HTGR Vessel Material

    Energy Technology Data Exchange (ETDEWEB)

    Larry Demick

    2012-06-01

    This paper examines the influence of High Temperature Gas-cooled Reactor (HTGR) module power rating and normal operating temperatures on the use of SA508/533 material for the HTGR vessel system with emphasis on the calculated times at elevated temperatures approaching or exceeding ASME Code Service Limits (Levels B&C) to which the reactor pressure vessel could be exposed during postulated pressurized and depressurized conduction cooldown events over its design lifetime.

  14. EFFECT OF SIZE OF INTESTINAL DIVERSIONS IN OBESE PATIENTS WITH METABOLIC SYNDROME SUBMITTED TO GASTRIC BYPASS

    Science.gov (United States)

    RAMOS, Rafael Jacques; MOTTIN, Cláudio Corá; ALVES, Letícia Biscaino; BENZANO, Daniela; PADOIN, Alexandre Vontobel

    2016-01-01

    ABSTRACT Background: There is no consensus on the ideal size of intestinal loops in gastric bypass of bariatric surgeries. Aim: To evaluate the metabolic outcome of patients submitted to gastric bypass with alimentary and biliopancreatic loops of different sizes. Methods: Was conducted a retrospective cohort study in diabetic obese patients (BMI≥35 kg/m2) with metabolic syndrome submitted to gastric bypass. The patients were divided into three groups according to the size of the intestinal loop: group 1, biliopancreatic limb 50 cm length and alimentary limb 100 cm length; group 2 , biliopancreatic limb 50 cm length and alimentary limb 150 cm length; and group 3, biliopancreatic limb 100 cm length and alimentary limb 150 cm length. The effect of gastric bypass with different sizes of intestinal loops in relation to the parameters that define metabolic syndrome was determined. Results: Sixty-three patients were evaluated, and they had a mean age of 44.7±9.4 years. All were diabetics, with 62 (98.4%) being hypertensive and 51 (82.2%) dyslipidemic. The three groups were homogeneous in relation to the variables. In 24 months, there was a remission of systemic arterial hypertension in 65% of patients in group 1, 62.5% in group 2 and 68.4% in group 3. Remission of diabetes occurred in 85% of patients in group 1, 83% in group 2 and 84% in group 3. There was no statistical difference in %LEW between the groups, and waist measurements decreased in a homogeneous way in all groups. The size of loops also had no influence on the improvement in dyslipidemia. Conclusion: Variation in size of intestinal loops does not appear to influence improvement in metabolic syndrome in this group of patients. PMID:27683768

  15. Complement activation in coronary artery bypass grafting patients without cardiopulmonary bypass - The role of tissue injury by surgical incision

    NARCIS (Netherlands)

    Gu, YJ; Mariani, MA; Boonstra, PW; Grandjean, JG; van Oeveren, W

    1999-01-01

    Study objectives: Complement activation is a trigger in inducing inflammation in patients who undergo coronary artery bypass grafting (CABG) and is usually thought to be induced by the use of cardiopulmonary bypass (CPB), In this study, we examined whether tissue injury caused by chest surgical inci

  16. Effects of residual coronary artery disease on results of coronary artery bypass grafting.

    Science.gov (United States)

    Iskandrian, A S; Hakki, A H; Nestico, P F; DePace, N L; Goel, I P; Kane, S

    1984-10-01

    To assess the effects of residual coronary artery disease (non-revascularized coronary vessels) after coronary artery bypass grafting on symptoms and exercise left ventricular function, we categorized 77 patients into 3 groups according to the extent of residual coronary artery disease: group I (n = 17) had no residual coronary artery disease (residual score = 0); group II (n = 30) had light residual coronary artery disease (score of 1 to 9, mean 4.7); and group III (n = 30) had moderate residual coronary artery disease (score greater than or equal to 10, mean 23). Sixty patients were asymptomatic after coronary artery bypass grafting (14 in group I, 24 in group II, and 22 in group III), but the remaining patients had occasional angina pectoris. The resting left ventricular ejection fraction was significantly higher in group I than in the remaining 2 groups (56 +/- 18% in group I, 47 +/- 19% in group II, and 43 +/- 16% in group III, P less than 0.05). The exercise left ventricular ejection fraction was also significantly higher in group I (61 +/- 16% in group I, 51 +/- 18% in group II and 45 +/- 18% in group III, P less than 0.01). The ejection fraction response to exercise was abnormal in 5 patients in group I, 15 patients in group II, and 19 patients in group III. Thus, coronary artery bypass grafting results in symptomatic improvement, even in patients with residual coronary artery disease. The presence of residual coronary artery disease, however, may be a determinant of exercise left ventricular function in these patients.

  17. Off-pump Coronary Endarterectomy and Bypass Grafting in Patients With Diffuse Coronary Artery Disease

    Institute of Scientific and Technical Information of China (English)

    Chen Xin; Xu Ming; Jiang Yinshuo; Sui Kaihu; Qiu Zhibing; Wang Liming; Liu Peisheng

    2006-01-01

    Objectives To summarize our preliminary experience on off-pump coronary endarterectomy and bypass grafting in patients with diffuse coronary artery disease. Methods Over a 3-year period, 53 patients (41 male) with diffuse coronary artery disease underwent off-pump coronary endarterectomy and bypass grafting at our institution.Patients' age ranged from 55 to 79 years. Prior to surgery, 70% of patients were in CCS angina class 2 (n=5) or 3 (n=32), and nearly half of them (26/53) had history of myocardial infarction. Most patients (n=50) had triple vessel lesions, with left main stem involvement in 9. Their left ventricular ejection fraction ranged from 26% to 65% (mean 52%). At the end of operation, a flow-meter was routinely applied to measure the perfusion flow of each postendarterectomy graft. Results In total, 70 endarterectomies were performed in 53 patients, including 38 in left anterior descending artery (LAD), 8 in circumflex artery and 24 in right coronary artery. Four operations were emergency or urgent in nature. Five patients received on-lay venous patch after endarterectomy in LAD, followed by left internal mammary artery (LIMA) grafting on the patch. The graft conduits included 53 LIMAs and 2 radial arteries,and saphenous veins in others. Mean number of grafts per patient was 3.75. The overall index of completeness of revascularization reached 1.03±0.07. There was no death in this group of patients during their post-operative hospital stay (mean duration = 9 days).Intra-operatively, 63 (90%) out of the 70 grafts after coronary endarterectomy showed satisfactory flow. Two patients had perioperative myocardial infarctions but neither experienced significant hemodynamic deteriations. Conclusions Off-pump coronary endarterectomy with bypass grafting is technically feasible and can be performed safely in patients with diffuse coronary artery disease. This strategy may help to improve the completeness of myocardial revascularization.

  18. Fusiform superior cerebellar artery aneurysm treated with STA-SCA bypass and trapping

    Directory of Open Access Journals (Sweden)

    Fabricio C Lamis

    2014-01-01

    Full Text Available Background: Fusiform aneurysms of cerebellar arteries are rare. Different surgical techniques to address these challenging lesions have been described, and their application depends on whether the goal is to maintain the flow in the parent vessel or to occlude it. Case Description: The authors reported a case of a fusiform aneurysm located in the lateral pontomesencephalic segment of the superior cerebellar artery (SCA in a 32-year-old man who presented with subarachnoid hemorrhage. The patient was subjected to aneurysm trapping followed by a bypass between the superficial temporal artery (STA and SCA and had an uneventful recovery. Conclusions: Although only a few cases of fusiform aneurysms in the supracerebellar artery have been reported in the literature, the treatment strategies adopted were diverse. In selected cases of patients in good neurological condition with ruptured fusiform aneurysms at the proximal segments of SCA and who have poor evidence of collateral supply, the possibility of a STA-SCA bypass with aneurysm trapping must be considered. A review of the current treatment modalities of this pathology is also presented.

  19. Coronary artery bypass grafting hemodynamics and anastomosis design: a biomedical engineering review

    Science.gov (United States)

    2013-01-01

    In this paper, coronary arterial bypass grafting hemodynamics and anastomosis designs are reviewed. The paper specifically addresses the biomechanical factors for enhancement of the patency of coronary artery bypass grafts (CABGs). Stenosis of distal anastomosis, caused by thrombosis and intimal hyperplasia (IH), is the major cause of failure of CABGs. Strong correlations have been established between the hemodynamics and vessel wall biomechanical factors and the initiation and development of IH and thrombus formation. Accordingly, several investigations have been conducted and numerous anastomotic geometries and devices have been designed to better regulate the blood flow fields and distribution of hemodynamic parameters and biomechanical factors at the distal anastomosis, in order to enhance the patency of CABGs. Enhancement of longevity and patency rate of CABGs can eliminate the need for re-operation and can significantly lower morbidity, and thereby reduces medical costs for patients suffering from coronary stenosis. This invited review focuses on various endeavors made thus far to design a patency-enhancing optimized anastomotic configuration for the distal junction of CABGs. PMID:24330653

  20. Coronary artery bypass grafting hemodynamics and anastomosis design: a biomedical engineering review.

    Science.gov (United States)

    Ghista, Dhanjoo N; Kabinejadian, Foad

    2013-12-13

    In this paper, coronary arterial bypass grafting hemodynamics and anastomosis designs are reviewed. The paper specifically addresses the biomechanical factors for enhancement of the patency of coronary artery bypass grafts (CABGs). Stenosis of distal anastomosis, caused by thrombosis and intimal hyperplasia (IH), is the major cause of failure of CABGs. Strong correlations have been established between the hemodynamics and vessel wall biomechanical factors and the initiation and development of IH and thrombus formation. Accordingly, several investigations have been conducted and numerous anastomotic geometries and devices have been designed to better regulate the blood flow fields and distribution of hemodynamic parameters and biomechanical factors at the distal anastomosis, in order to enhance the patency of CABGs. Enhancement of longevity and patency rate of CABGs can eliminate the need for re-operation and can significantly lower morbidity, and thereby reduces medical costs for patients suffering from coronary stenosis. This invited review focuses on various endeavors made thus far to design a patency-enhancing optimized anastomotic configuration for the distal junction of CABGs.

  1. Intraoperative perfusion contrast echocardiography. Initial experience during coronary artery bypass grafting.

    Science.gov (United States)

    Kabas, J S; Kisslo, J; Flick, C L; Johnson, S H; Craig, D M; Stanley, T E; Smith, P K

    1990-03-01

    Intraoperative evaluation of the effectiveness of myocardial revascularization has been limited by an inability to assess regional myocardial perfusion. Microbubbles of sonicated diatrizoate sodium and diatrizoate meglumine (Renografin) have been an effective echocardiographic contrast agent and have been employed clinically during cardiac catheterization. This recent development in contrast-enhanced two-dimensional echocardiography permits real-time imaging of transmural myocardial blood flow but has not been evaluated in the operating room. This study represents the initial surgical application of this directed technique and was designed to evaluate the safety and efficacy of intraoperative perfusion contrast echocardiography in assessing the results of coronary artery bypass grafting. Twenty men with significant coronary artery disease ranging in age from 49 to 73 years were studied. Direct contrast agent injection into completed saphenous vein bypass grafts caused the myocardium supplied by each graft to be well delineated and provided a tomographic view of contrast distribution. The enhanced region was well correlated with the size and distribution of the native vessel. Rapid contrast washout (less than 20 seconds) indicated satisfactory regional perfusion. Contrast echocardiography prolonged the operation less than 10 minutes and did not result in any perioperative complications.

  2. Guillain-Barré Syndrome after Coronary Artery Bypass Graft Surgery: a Case Report.

    Science.gov (United States)

    Hekmat, Manouchehr; Ghaderi, Hamid; Foroughi, Mahnoosh; Mirjafari, S Adeleh

    2016-01-01

    Guillain-Barre syndrome is a neurologic disorder that may appear after infection or major surgery. Guillain-Barré syndrome following cardiac surgery is rare and only based on case reports, and we review all of the published cases. A 52-year-old man after 5 months suffering from chest pain was referred to our hospital and underwent coronary artery bypass graft for 3 vessel disease. The patient was discharged without complication on the 5th postoperative day. He presented Guillain-Barré syndrome after 12 months. He has not completely recovered weakness of upper extremities grade 4/5 with atrophy of both upper extremities remains after 18 months. This disorder is similar to classic GBS. It is important to be alert to de novo autoimmune neurological disorders after cardiac surgery. These disorders are similar to classic autoimmune disease and treated with standard therapies.

  3. Total Arterial Revascularization: Bypassing Antiquated Notions to Better Alternatives for Coronary Artery Disease

    Science.gov (United States)

    Samak, Mostafa; Fatullayev, Javid; Sabashnikov, Anton; Zeriouh, Mohamed; Schmack, Bastian; Ruhparwar, Arjang; Karck, Matthias; Popov, Aron-Frederik; Dohmen, Pascal M.; Weymann, Alexander

    2016-01-01

    Total arterial revascularization is the leading trend in coronary artery bypass grafting (CABG) for the treatment of coronary artery disease (CAD). Adding to its superiority to vein conduits, arteries allow for a high degree of versatility and long-term patency, while minimizing the need for reintervention. This is especially important for patients with multi-vessel coronary artery disease, as well as young patients. However, arterial revascularization has come a long way before being widely appreciated, with some yet unresolved debates, and advances that never cease to impress. In this review, we discuss the evolution of this surgical technique and its clinical success, as well as its most conspicuous limitations in light of accumulated published date from decades of experience. PMID:27698339

  4. A marked increase in gastric fluid volume during cardiopulmonary bypass

    Science.gov (United States)

    Hirota, Kazuyoshi; Kudo, Mihoko; Hashimoto, Hiroshi; Kushikata, Tetsuya

    2011-01-01

    Major physiological stress occurs during cardiac surgery with cardiopulmonary bypass. This is related to hypothermia and artificial organ perfusion. Thus, serious gastrointestinal complications, particularly upper gastrointestinal bleeding, sometimes follow cardiac surgery. We have compared the antisecretory effects of a preanesthetic H2 antagonist (roxatidine, cardiopulmonary bypass-H2 group, n = 15) and a proton pump inhibitor (rabeprazole, cardiopulmonary bypass-PPI group, n = 15) in patients undergoing cardiac surgery with cardiopulmonary bypass, and also compared in patients undergoing a off-pump coronary artery bypass graft surgery (off-pump cardiopulmonary bypass-H2 group, n = 15). Gastric pH (5.14 ± 0.61) and gastric fluid volume (13.2 ± 2.4 mL) at the end of surgery in off-pump cardiopulmonary bypass-H2 groups was significantly lower and higher than those in both cardiopulmonary bypass-H2 (6.25 ± 0.54, 51.3 ± 8.0 mL) and cardiopulmonary bypass-PPI (7.29 ± 0.13, 63.5 ± 14.8 mL) groups, respectively although those variables did not differ between groups after the induction of anesthesia. Plasma gastrin (142 ± 7 pg/mL) at the end of surgery and maximal blood lactate levels (1.50 ± 0.61 mM) in off-pump cardiopulmonary bypass-H2 group were also significantly lower than those in both cardiopulmonary bypass-H2 (455 ± 96 pg/mL, 3.97 ± 0.80 mM) and cardiopulmonary bypass-PPI (525 ± 27 pg/mL, 3.15 ± 0.44 mM) groups, respectively. In addition, there was a significant correlation between gastric fluid volume and maximal blood lactate (r = 0.596). In conclusion, cardiopulmonary bypass may cause an increase in gastric fluid volume which neither H2 antagonist nor PPI suppresses. A significant correlation between gastric fluid volume and maximal blood lactate suggests that gastric fluid volume may predict degree of gastrointestinal tract hypoperfusion. PMID:21765601

  5. Bronze Vessel with Silkworm Motif

    Institute of Scientific and Technical Information of China (English)

    1995-01-01

    This artifact was a kind of sacrificial vessel used during the Shang and Zhou dynasties. Most patterns found on these pieces are the fierce and formidable faces of beasts or mysterious dragons, tigers and phoenixes. Rut the pattern on this vessel illustrates the life of a mulberry field.

  6. Bypass technology enhances the efficiency of wind power plants; Bypass-Technologie erhoeht WEA-Effizienz

    Energy Technology Data Exchange (ETDEWEB)

    Ebach, Thorsten [EKS Engel GmbH und Co. KG, Wenden (Germany)

    2013-04-01

    A reliable operation of wind power parks significantly depends on a trouble-free data communication. If one or more network participants break down, then it depends on the topology whether the complete power distribution system is available or not. An optical bypass such as it is supplied by EKS Engel GmbH and Co. KG (Wenden, Federal Republic of Germany) offers a remedial action.

  7. Modeling Of Blood Vessel Constriction In 2-D Case Using Molecular Dynamics Method

    CERN Document Server

    Rendi, Mohamad; Viridi, Sparisoma

    2013-01-01

    Blood vessel constriction is simulated with particle-based method using a molecular dynamics authoring software known as Molecular Workbench (WM). Blood flow and vessel wall, the only components considered in constructing a blood vessel, are all represented in particle form with interaction potentials: Lennard-Jones potential, push-pull spring potential, and bending spring potential. Influence of medium or blood plasma is accommodated in plasma viscosity through Stokes drag force. It has been observed that pressure p is increased as constriction c is increased. Leakage of blood vessel starts at 80 % constriction, which shows existence of maximum pressure that can be overcome by vessel wall.

  8. AUTOMATIC RETINAL VESSEL TORTUOSITY MEASUREMENT

    Directory of Open Access Journals (Sweden)

    Nidhal Khdhair El Abbadi

    2013-01-01

    Full Text Available Retinal vascular vessels have the role to indicate the retinal diseases and for systematic diseases when there are any abnormalities in retinal vascular pattern. A characteristic of the vascular pattern that is appreciated by clinicians is vascular tortuosity, i.e., how curved or kinked a blood vessel, either vein or artery, appears along its course. In this study we suggest a novel mask filter to track the blood vessel along its course and measuring the blood vessels tortuosity over the entire human retinal vessel network in fundus eye image, by using the arc to chord ratio. The suggested algorithm tested with straight and curve hand drawing lines and gives high accurate results.

  9. Strain Growth in Containment Vessels

    Institute of Scientific and Technical Information of China (English)

    DONG Q; LI Q M; ZHENG J Y

    2006-01-01

    Strain growth is a phenomenon observed in containment vessels subjected to internal blast loading.The elastic response of the vessel may become larger in a later stage compared to its response during the initial stage.The dynamic responses of infinitely long cylindrical containment vessels subjected to uniformly-distributed internal blast loading are studied using LS-DYNA.The development of bending modes and the interaction between the breathing mode and bending modes are observed.The methodology developed for dynamic elastic buckling analysis is employed to study the strain growth phenomenon in explosion containment vessels.It is shown that the dynamic instable vibration of a containment vessel is the basic mechanism of strain growth.

  10. Emergent cardiopulmonary bypass during pectus excavatum repair

    Directory of Open Access Journals (Sweden)

    Ryan Craner

    2013-01-01

    Full Text Available Pectus excavatum is a chest wall deformity that produces significant cardiopulmonary disability and is typically seen in younger patients. Minimally invasive repair of pectus excavatum or Nuss procedure has become a widely accepted technique for adult and pediatric patients. Although it is carried out through a thoracoscopic approach, the procedure is associated with a number of potential intraoperative and post-operative complications. We present a case of cardiac perforation requiring emergent cardiopulmonary bypass in a 29-year-old male with Marfan syndrome and previous mitral valve repair undergoing a Nuss procedure for pectus excavatum. This case illustrates the importance of vigilance and preparation by the surgeons, anesthesia providers as well as the institution to be prepared with resources to handle the possible complications. This includes available cardiac surgical backup, perfusionist support and adequate blood product availability.

  11. Transient Diabetes Insipidus Following Cardiopulmonary Bypass.

    Science.gov (United States)

    Ekim, Meral; Ekim, Hasan; Yilmaz, Yunus Keser; Bolat, Ali

    2015-04-01

    Diabetes insipidus (DI) results from inadequate output of Antidiuretic Hormone (ADH) from the pituitary gland (central DI) or the inability of the kidney tubules to respond to ADH (nephrogenic DI). ADH is an octapeptide produced in the supraoptic and paraventricular nuclei of the hypothalamus and stored in the posterior lobe of the pituitary gland. Cardiopulmonary Bypass (CPB) has been shown to cause a six-fold increased circulating ADH levels 12 hours after surgery. However, in some cases, ADH release may be transiently suppressed due to cardioplegia (cardiac standstill) or CPB leading to DI. We present the postoperative course of a 60-year-old man who developed transient DI after CPB. He was successfully treated by applying nasal desmopressin therapy. Relevant biochemical parameters should be monitored closely in patients who produce excessive urine after open heart surgery.

  12. CFD Analysis of Core Bypass Phenomena

    Energy Technology Data Exchange (ETDEWEB)

    Richard W. Johnson; Hiroyuki Sato; Richard R. Schultz

    2009-11-01

    The U.S. Department of Energy is exploring the potential for the VHTR which will be either of a prismatic or a pebble-bed type. One important design consideration for the reactor core of a prismatic VHTR is coolant bypass flow which occurs in the interstitial regions between fuel blocks. Such gaps are an inherent presence in the reactor core because of tolerances in manufacturing the blocks and the inexact nature of their installation. Furthermore, the geometry of the graphite blocks changes over the lifetime of the reactor because of thermal expansion and irradiation damage. The existence of the gaps induces a flow bias in the fuel blocks and results in unexpected increase of maximum fuel temperature. Traditionally, simplified methods such as flow network calculations employing experimental correlations are used to estimate flow and temperature distributions in the core design. However, the distribution of temperature in the fuel pins and graphite blocks as well as coolant outlet temperatures are strongly coupled with the local heat generation rate within fuel blocks which is not uniformly distributed in the core. Hence, it is crucial to establish mechanistic based methods which can be applied to the reactor core thermal hydraulic design and safety analysis. Computational Fluid Dynamics (CFD) codes, which have a capability of local physics based simulation, are widely used in various industrial fields. This study investigates core bypass flow phenomena with the assistance of commercial CFD codes and establishes a baseline for evaluation methods. A one-twelfth sector of the hexagonal block surface is modeled and extruded down to whole core length of 10.704m. The computational domain is divided vertically with an upper reflector, a fuel section and a lower reflector. Each side of the one-twelfth grid can be set as a symmetry boundary

  13. CFD Analysis of Core Bypass Phenomena

    Energy Technology Data Exchange (ETDEWEB)

    Richard W. Johnson; Hiroyuki Sato; Richard R. Schultz

    2010-03-01

    The U.S. Department of Energy is exploring the potential for the VHTR which will be either of a prismatic or a pebble-bed type. One important design consideration for the reactor core of a prismatic VHTR is coolant bypass flow which occurs in the interstitial regions between fuel blocks. Such gaps are an inherent presence in the reactor core because of tolerances in manufacturing the blocks and the inexact nature of their installation. Furthermore, the geometry of the graphite blocks changes over the lifetime of the reactor because of thermal expansion and irradiation damage. The existence of the gaps induces a flow bias in the fuel blocks and results in unexpected increase of maximum fuel temperature. Traditionally, simplified methods such as flow network calculations employing experimental correlations are used to estimate flow and temperature distributions in the core design. However, the distribution of temperature in the fuel pins and graphite blocks as well as coolant outlet temperatures are strongly coupled with the local heat generation rate within fuel blocks which is not uniformly distributed in the core. Hence, it is crucial to establish mechanistic based methods which can be applied to the reactor core thermal hydraulic design and safety analysis. Computational Fluid Dynamics (CFD) codes, which have a capability of local physics based simulation, are widely used in various industrial fields. This study investigates core bypass flow phenomena with the assistance of commercial CFD codes and establishes a baseline for evaluation methods. A one-twelfth sector of the hexagonal block surface is modeled and extruded down to whole core length of 10.704m. The computational domain is divided vertically with an upper reflector, a fuel section and a lower reflector. Each side of the sector grid can be set as a symmetry boundary

  14. Alongshore sediment bypassing as a control on river mouth morphodynamics

    Science.gov (United States)

    Nienhuis, Jaap H.; Ashton, Andrew D.; Nardin, William; Fagherazzi, Sergio; Giosan, Liviu

    2016-04-01

    River mouths, shoreline locations where fluvial and coastal sediments are partitioned via erosion, trapping, and redistribution, are responsible for the ultimate sedimentary architecture of deltas and, because of their dynamic nature, also pose great management and engineering challenges. To investigate the interaction between fluvial and littoral processes at wave-dominated river mouths, we modeled their morphologic evolution using the coupled hydrodynamic and morphodynamic model Delft3D-SWAN. Model experiments replicate alongshore migration of river mouths, river mouth spit development, and eventual spit breaching, suggesting that these are emergent phenomena that can develop even under constant fluvial and wave conditions. Furthermore, we find that sediment bypassing of a river mouth develops though feedbacks between waves and river mouth morphology, resulting in either continuous bypassing pathways or episodic bar bypassing pathways. Model results demonstrate that waves refracting into the river mouth bar create a zone of low alongshore sediment transport updrift of the river mouth, which reduces sediment bypassing. Sediment bypassing, in turn, controls the river mouth migration rate and the size of the river mouth spit. As a result, an intermediate amount of river discharge maximizes river mouth migration. The fraction of alongshore sediment bypassing can be predicted from the balance between the jet and the wave momentum flux. Quantitative comparisons show a match between our modeled predictions of river mouth bypassing and migration rates observed in natural settings.

  15. Passive Acoustic Vessel Localization

    Science.gov (United States)

    Suwal, Pasang Sherpa

    This thesis investigates the development of a low-cost passive acoustic system for localizing moving vessels to monitor areas where human activities such as fishing, snorkeling and poaching are restricted. The system uses several off-the-shelf sensors with unsynchronized clocks where the Time Difference of Arrival (TDOA) or time delay is extracted by cross-correlation of the signal between paired sensors. The cross-correlation function uses phase correlation or Phase Transform (PHAT) which whitens the cross-spectrum in order to de-emphasize dominant frequency components. Using the locations of pairs of sensors as foci, hyperbolic equations can be defined using the time delay between them. With three or more sensors, multiple hyperbolic functions can be calculated which intersect at a unique point: the boat's location. It is also found that increasing separation distances between sensors decreased the correlation between the signals. However larger separation distances have better localization capability than with small distances. Experimental results from the Columbia and Willamette Rivers are presented to demonstrate performance.

  16. Seasonal Variation of Climatological Bypassing Flows around the Tibetan Plateau

    Institute of Scientific and Technical Information of China (English)

    LI Qiang; ZHANG Renhe

    2012-01-01

    The present study investigated diagnostically the seasonal variation of the bypassing flows caused by the splitting effect of the Tibetan Plateau (TP).The relationships among the splitting bypassing flows around the TP to precipitation in China,the westerly jet stream,and the thermal status over the TP are revealed.The bypassing flows occur from the 1st to the 22nd pentad and from the 59th to the 73rd pentad,respectively,and they disappear from the 29th to the 58th pentad.They are strongest in winter from the 1st to the 22nd pentad and from the 59th to the 73rd pentad,respectively.During the rebuilding of the bypassing flows from mid-October to mid-February,they are the main cause of precipitation over southeastern China.The enhancement of the bypassing flow intensity in March cau cause the precipitation to increase in the early stage of the persistent spring rain over southeastern China.From winter to summer,the seasonal transition of the bypassing flows in the lower troposphere precedes that of the westerly jet stream axis in the upper troposphere to the west of the TP by ~4 pentads,while from summer to winter lags by ~4 pentads.The seasonal variation of the thermal status over the TP plays an important role in the bypassing flows around the TP.The strengthening of the heating over the TP weakens the bypassing flows,and the increase in cooling over the TP is related to the rebuilding and strengthening of the bypassing flows.

  17. Hypothermia During Cardiopulmonary Bypass Increases Need for Inotropic Support but Does Not Impact Inflammation in Children Undergoing Surgical Ventricular Septal Defect Closure.

    Science.gov (United States)

    Schmitt, Katharina Rose Luise; Fedarava, Katsiaryna; Justus, Georgia; Redlin, Mathias; Böttcher, Wolfgang; Delmo Walter, Eva Maria; Hetzer, Roland; Berger, Felix; Miera, Oliver

    2016-05-01

    Minimizing the systemic inflammatory response caused by cardiopulmonary bypass is a major concern. It has been suggested that the perfusion temperature affects the inflammatory response. The aim of this prospective study was to compare the effects of moderate hypothermia (32°C) and normothermia (36°C) during cardiopulmonary bypass on markers of the inflammatory response and clinical outcomes (time on ventilator) after surgical closure of ventricular septal defects. During surgical closure of ventricular septal defects under cardiopulmonary bypass, 20 children (median age 4.9 months, range 2.3-38 months; median weight 7.2 kg, range 5.2-11.7 kg) were randomized to a perfusion temperature of either 32°C (Group 1, n = 10) or 36°C (Group 2, n = 10). The clinical data and blood samples were collected before cardiopulmonary bypass, directly after aortic cross-clamp release, and 4 and 24 h after weaning from cardiopulmonary bypass. Time on ventilation as primary outcome did not differ between the two groups. Other clinical outcome parameters like fluid balance or length of stay in the intensive care were also similar in the two groups. Compared with Group 2, Group 1 needed significantly higher and longer inotropic support (P bypass temperature does not influence time on ventilation or inflammatory marker release. However, in the present study, with a small patient cohort, patients operated under hypothermic bypass needed higher and longer inotropic support. The use of hypothermic cardiopulmonary bypass in infants and children should be approached with care.

  18. Asendan Desendan Aortic Bypass: Atan Kalpte Mediyan Sternotomi Yoluyla Onarim

    Directory of Open Access Journals (Sweden)

    Muhammet Akyuz

    2013-10-01

    Full Text Available We report the case of a 9-month-old patient presenting for redo aortic arch surgery because of recoarctation. In present case, ascending-to-descending aortic bypass via median sternotomy was performed without cardiopulmonary bypass with good result. In spite of the fact that the different surgical and intervention treatment options of aortic coarctation are quite satisfactory, a certain group of patients need reoperation because of recoarctation. The recoarctation repair of the aorta with the extra-anatomic aortic bypass is considered a low-risk procedure with high success rate.

  19. 34 CFR 300.198 - Continuation of a by-pass.

    Science.gov (United States)

    2010-07-01

    ... 34 Education 2 2010-07-01 2010-07-01 false Continuation of a by-pass. 300.198 Section 300.198... CHILDREN WITH DISABILITIES State Eligibility By-Pass for Children in Private Schools § 300.198 Continuation of a by-pass. The Secretary continues a by-pass until the Secretary determines that the SEA, LEA...

  20. 34 CFR 300.192 - Notice of intent to implement a by-pass.

    Science.gov (United States)

    2010-07-01

    ... 34 Education 2 2010-07-01 2010-07-01 false Notice of intent to implement a by-pass. 300.192... EDUCATION OF CHILDREN WITH DISABILITIES State Eligibility By-Pass for Children in Private Schools § 300.192 Notice of intent to implement a by-pass. (a) Before taking any final action to implement a by-pass,...

  1. 34 CFR 300.191 - Provisions for services under a by-pass.

    Science.gov (United States)

    2010-07-01

    ... 34 Education 2 2010-07-01 2010-07-01 false Provisions for services under a by-pass. 300.191... EDUCATION OF CHILDREN WITH DISABILITIES State Eligibility By-Pass for Children in Private Schools § 300.191 Provisions for services under a by-pass. (a) Before implementing a by-pass, the Secretary consults...

  2. Blood flow dynamics, atherosclerosis and bypass graft failure.

    Science.gov (United States)

    Langille, B L; Ojha, M

    1997-05-01

    Atherosclerosis occurs at reproducible sites in the arterial tree and intimal proliferation that leads to bypass graft occlusion also show a well-defined focal distribution. These observations have led to the hypothesis that local blood flow conditions, especially low or fluctuating shear stresses, are important in the development of both disorders. Basic research using both cell culture and animal models has revealed that endothelial cell biology is very sensitive to local shear stresses and rapid progress is being made in characterizing how endothelial cells transduce shear stress. Endothelial sensitivity to shear stress affects control of hemostasis, leukocyte adherence and transmigration, growth factor production, vasomotor responses, endothelial repair and arterial wall remodeling, all of which can be expected to influence development of vascular pathologies. Also, substantial progress has been made in characterizing complex local hemodynamics at relevant arterial sites; however, further progress is needed in this area, as well as in the extrapolation of advances in basic vascular biology to human vascular disease. (Trends Cardiovasc Med 1997;7:111-118). © 1997, Elsevier Science Inc.

  3. Southeast Region Headboat Survey-Vessel list/Vessel Directory

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — This is a database of vessels that have been on the SRHS through time, their owners/operators, marinas/docks and their contact information. This assists in...

  4. BY FRUSTUM CONFINING VESSEL

    Directory of Open Access Journals (Sweden)

    Javad Khazaei

    2016-09-01

    Full Text Available Helical piles are environmentally friendly and economical deep foundations that, due to environmental considerations, are excellent additions to a variety of deep foundation alternatives available to the practitioner. Helical piles performance depends on soil properties, the pile geometry and soil-pile interaction. Helical piles can be a proper alternative in sensitive environmental sites if their bearing capacity is sufficient to support applied loads. The failure capacity of helical piles in this study was measured via an experimental research program that was carried out by Frustum Confining Vessel (FCV. FCV is a frustum chamber by approximately linear increase in vertical and lateral stresses along depth from top to bottom. Due to special geometry and applied bottom pressure, this apparatus is a proper choice to test small model piles which can simulate field stress conditions. Small scale helical piles are made with either single helix or more helixes and installed in fine grained sand with three various densities. Axial loading tests including compression and tension tests were performed to achieve pile ultimate capacity. The results indicate the helical piles behavior depends essentially on pile geometric characteristics, i.e. helix configuration and soil properties. According to the achievements, axial uplift capacity of helical model piles is about equal to usual steel model piles that have the helixes diameter. Helical pile compression bearing capacity is too sufficient to act as a medium pile, thus it can be substituted other piles in special geoenvironmental conditions. The bearing capacity also depends on spacing ratio, S/D, and helixes diameter.

  5. Reactor vessel support system. [LMFBR

    Science.gov (United States)

    Golden, M.P.; Holley, J.C.

    1980-05-09

    A reactor vessel support system includes a support ring at the reactor top supported through a box ring on a ledge of the reactor containment. The box ring includes an annular space in the center of its cross-section to reduce heat flow and is keyed to the support ledge to transmit seismic forces from the reactor vessel to the containment structure. A coolant channel is provided at the outside circumference of the support ring to supply coolant gas through the keyways to channels between the reactor vessel and support ledge into the containment space.

  6. Ventilation during cardiopulmonary bypass for prevention of respiratory insufficiency

    Science.gov (United States)

    Chi, Dongmei; Chen, Chan; Shi, Yu; Wang, Wanyu; Ma, Ye; Zhou, Ronghua; Yu, Hai; Liu, Bin

    2017-01-01

    Abstract Background: Cardiopulmonary bypass (CPB) is necessary for most cardiac surgery, which may lead to postoperative lung injury. The objective of this paper is to systematically evaluate whether ventilation during CPB would benefit patients undergoing cardiac surgery. Methods: We searched randomized controlled trials (RCTs) through PubMed, Embase, and Cochrane Library from inception to October 2016. Eligible studies compared clinical outcomes of ventilation versus nonventilation during CPB in patients undergoing cardiac surgery. The primary outcome includes oxygenation index (PaO2/FiO2 ratio) or alveolar to arterial oxygen tension difference (AaDO2) immediately after weaning from bypass. The secondary outcomes include postoperative pulmonary complications (PPCs), shunt fraction (Qs/Qt), hospital stay, and AaDO2 4 hours after CPB. Results: Seventeen trials with 1162 patients were included in this meta-analysis. Ventilation during CPB significantly increased post-CPB PaO2/FiO2 ratio (mean difference [MD] = 21.84; 95% confidence interval [CI] = 1.30 to 42.37; P = 0.04; I2 = 75%) and reduced post-CPB AaDO2 (MD = –50.17; 95% CI = –71.36 to –28.99; P <0.00001; I2 = 74%). Qs/Qt immediately after weaning from CPB showed a significant difference between groups (MD = –3.24; 95% CI = –4.48 to –2.01; P <0.00001; I2 = 0%). Incidence of PPCs (odds ratio [OR] = 0.79; 95% CI = 0.42 to 1.48; P = 0.46; I2 = 37%) and hospital stay (MD = 0.09; 95% CI = –23 to 0.41; P = 0.58; I2 = 37%) did not differ significantly between groups. Conclusion: Ventilation during CPB might improve post-CPB oxygenation and gas exchange in patients who underwent cardiac surgery. However, there is no sufficient evidence to show that ventilation during CPB could influence long-term prognosis of these patients. The beneficial effects of ventilation during CPB are requisite to be evaluated in powerful and well

  7. 46 CFR 298.11 - Vessel requirements.

    Science.gov (United States)

    2010-10-01

    ... reconditioning of a Vessel as a condition for issuance of the Letter Commitment. The estimated cost of the Vessel may include escalation for the anticipated construction period of the Vessel. We may contact...

  8. A influência do anel na evolução ponderal após quatro anos da derivação gástrica em y-de-roux laparoscópica Ring influence on ponderal evolution after four years of laparoscopic Roux-en-Y gastric bypass

    Directory of Open Access Journals (Sweden)

    Irineu Rasera-Junior

    2012-12-01

    ção do anel ao se analisar exclusivamente a perda de peso.BACKGROUND: Use of ring in Roux-en-Y gastric bypass is still a matter of controversy among bariatric surgeons. There is no consensus on its impact in relation to weight loss and weight maintenance in the long term. AIM: To evaluate the influence of the ring on the evolution of body weight over four years after bariatric surgery. METHODS: Retrospective analyzis of 143 women who underwent laparoscopic Roux-en-Y gastric bypass paired on the use or not use of Silastic® ring. Follow-up time was 48 months. Inclusion criteria were age over 18 years, primary bariatric operation and regular attendance at the clinic during the period of interest for research. The technique kept small gastric reservoir estimated in a volume of 30 ml. The food limb had in average 150 cm and the bile one 40 cm from the duodenojejunal angle. The group "ring" used Silastic® device with length of 6.5 cm, placed 2 cm from gastrojejunal anastomosis. The ring was closed for five polypropylene surgical thread sutures. In the morning after surgery the patients received isotonic fluids; on the second day salty liquid diet and were discharged on the third day. Semisolid diet started from the 20th day and solid on the 30th, with daily tablet of polivitamins. RESULTS: The weight loss was larger on the ring than without ring groups in all periods, respectively 10% and only 5% in the third postoperative year. The proportion of not having reached the 50% excess weight loss expectative was significantly higher in the group without ring than in the group with the ring (31% and 8% respectively in the fourth year. There was no difference between groups in delayed recovery of weight lost with the operation. CONCLUSIONS: The results were favorable to use the ring exclusively when it is analyzed only the weight loss.

  9. Minimally invasive coronary artery bypass grafting versus stenting for patients with proximal left anterior descending coronary artery disease.

    Science.gov (United States)

    Shirai, Kazuyuki; Lansky, Alexandra J; Mehran, Roxana; Dangas, George D; Costantini, Costantino O; Fahy, Martin; Slack, Steven; Mintz, Gary S; Stone, Gregg W; Leon, Martin B

    2004-04-15

    The purpose of this study was to compare the clinical outcomes of stenting and minimally invasive coronary artery bypass grafting (MIDCAB) in patients with proximal left anterior descending (LAD) coronary artery disease. The Patency, Outcome, Economics of Minimally invasive direct coronary bypass (POEM) study demonstrated that MIDCAB had similar safety and long-term efficacy for LAD revascularization compared with conventional coronary artery bypass grafting. Although LAD stenting is superior to conventional balloon angioplasty, whether it is comparable to MIDCAB is not known. We identified a matched population of 429 consecutive patients with 1-vessel disease who underwent elective proximal LAD stenting and compared their clinical outcomes with those of the 152 patients in the MIDCAB group of the POEM study. The in-hospital event rate was similar in both groups, except for a shorter length of hospital stay with LAD stenting compared with MIDCAB (2.68 vs 4.07 days, p <0.0001). At 6-month follow-up, the incidence of death and Q-wave myocardial infarction or that of cerebrovascular accident was not significantly different between these 2 groups. However, target vessel revascularization was significantly higher with LAD stenting than MIDCAB (13.3% vs 6.6%, p = 0.045). In the subgroup of patients without diabetes, all clinical events were similar in both groups, and the benefit of a shorter hospital stay associated with stenting was maintained. Compared with MIDCAB, LAD stenting is associated with higher repeat revascularization rates but offers the advantage of shorter hospitalization. For nondiabetics with proximal LAD disease, stenting may be the revascularization strategy of choice.

  10. Severe hypoglycaemia post-gastric bypass requiring partial pancreatectomy

    DEFF Research Database (Denmark)

    Patti, M E; McMahon, G; Mun, E C;

    2005-01-01

    was assessed in all three patients. RESULTS: All three patients had evidence of severe postprandial hyperinsulinaemia and hypoglycaemia. In one patient, reversal of gastric bypass was ineffective in reversing hypoglycaemia. All three patients ultimately required partial pancreatectomy for control...

  11. [Psychoprophylaxis in patients after coronary artery bypass graft operations].

    Science.gov (United States)

    Rymaszewska, Joanna; Chładzińska-Kiejna, Sylwia; Górna, Renata; Kustrzycki, Wojciech

    2004-05-01

    The paper presented problems of quality of life and psychosocial functioning of patients following coronary artery bypass grafting operations. Possibilities of psychoprophylactic effects towards these patients and its efficacy were described.

  12. Value of Optical Bypass in Packet Ring Networks

    Institute of Scientific and Technical Information of China (English)

    2003-01-01

    This paper firstly examines the value of optical bypass scheme in packet ring networks. An Integer Linear Program (ILP) formulation is presented and analytical results under different traffic patterns are given.

  13. Oil Bypass Filter Technology Performance Evaluation - January 2003 Quarterly Report

    Energy Technology Data Exchange (ETDEWEB)

    Laurence R. Zirker; James E. Francfort

    2003-01-01

    This report details the initial activities to evaluate the performance of the oil bypass filter technology being tested by the Idaho National Engineering and Environmental Laboratory (INEEL) for the U.S. Department of Energy's FreedomCAR & Vehicle Technologies Program. Eight full-size, four-cycle diesel-engine buses used to transport INEEL employees on various routes have been equipped with oil bypass systems from the puraDYN Corporation. Each bus averages about 60,000 miles a year. The evaluation includes an oil analysis regime to monitor the presence of necessary additives in the oil and to detect undesirable contaminants. Very preliminary economic analysis suggests that the oil bypass system can reduce life-cycle costs. As the evaluation continues and oil avoidance costs are quantified, it is estimated that the bypass system economics may prove increasingly favorable, given the anticipated savings in operational costs and in reduced use of oil and waste oil avoidance.

  14. Oil Bypass Filter Technology Performance Evaluation - First Quarterly Report

    Energy Technology Data Exchange (ETDEWEB)

    Zirker, L.R.; Francfort, J.E.

    2003-01-31

    This report details the initial activities to evaluate the performance of the oil bypass filter technology being tested by the Idaho National Engineering and Environmental Laboratory (INEEL) for the U.S. Department of Energy's FreedomCAR & Vehicle Technologies Program. Eight full-size, four-cycle diesel-engine buses used to transport INEEL employees on various routes have been equipped with oil bypass systems from the puraDYN Corporation. Each bus averages about 60,000 miles a year. The evaluation includes an oil analysis regime to monitor the presence of necessary additives in the oil and to detect undesirable contaminants. Very preliminary economic analysis suggests that the oil bypass system can reduce life-cycle costs. As the evaluation continues and oil avoidance costs are quantified, it is estimated that the bypass system economics may prove increasingly favorable, given the anticipated savings in operational costs and in reduced use of oil and waste oil avoidance.

  15. Prolonged successful therapy for hyperinsulinaemic hypoglycaemia after gastric bypass

    DEFF Research Database (Denmark)

    Myint, K S; Greenfield, J R; Farooqi, I S;

    2012-01-01

    Spontaneous hyperinsulinaemic hypoglycaemia following gastric bypass surgery (GBS) is increasingly recognised. However, its pathophysiology remains unclear. Some patients require pancreatectomy. Medical therapy with calcium channel blockers, acarbose and diazoxide has been reported to be beneficial...

  16. Antiplatelet therapy at the time of coronary artery bypass grafting

    DEFF Research Database (Denmark)

    Kremke, Michael; Tang, Mariann; Bak, Mikkel;

    2013-01-01

    OBJECTIVES: The purpose of this multicentre cohort study was to examine the relationship between antiplatelet therapy (APT) at the time of coronary artery bypass grafting (CABG) and postoperative bleeding complications, transfusion requirements and adverse cardiovascular events. METHODS: A matched...

  17. Canals, Bypass Canal, Published in 2002, Duchesne County.

    Data.gov (United States)

    NSGIC GIS Inventory (aka Ramona) — This Canals dataset, was produced all or in part from Other information as of 2002. It is described as 'Bypass Canal'. Data by this publisher are often provided in...

  18. Palliative surgical bypass for unresectable periampullar y carcinoma

    Institute of Scientific and Technical Information of China (English)

    Shivendra Singh; Ajay Kumar Sachdev; Adarsh Chaudhary; Anil Kumar Agarwal

    2008-01-01

    BACKGROUND:Around 60% to 80% of patients with periampullary carcinoma are unresectable either due to distant metastasis or local vascular invasion. With the advancement of endoscopic interventional procedures, the role of surgical bypass has diminished. However, surgical bypass is still appropriate in patients with unresectable disease discovered at the time of surgery. This study was conducted to assess the results of palliative surgical bypass for patients with unresectable periampullary carcinoma at our hospital, a tertiary referral center of Northern India. METHOD:The study group comprised 204 patients who had undergone surgical bypass for advanced periampullary carcinoma over the last 15 years. RESULTS:Between January 1990 and December 2004, 204 patients (128 males, 76 females) consisting of 179 patients with carcinoma of head of the pancreas, 14 patients with ampullary carcinoma, 8 patients with lower end cholangiocarcinoma and 3 patients with duodenal carcinoma underwent surgical bypass. Their average age was 51 years (range 20-78 years). Both biliary and gastric bypasses were done in 158 (77.45%), biliary bypass alone in 37 (18.13%), and gastric bypass alone in 9 (4.32%). Biliary bypass was done by Roux-en-Y hepaticojejunostomy, and gastric bypass by retrocolic gastrojejunostomy. The overall postoperative mortality and morbidity were 0.98%and 26.9%, respectively. The patients who died had undergone previously endoscopic intervention. Complications included wound infection in 12.25% of the patients, bile leak in 5.12%, delayed gastric emptying in 5.38%, ascitic leak from drains in 8.8%, and upper gastrointestinal bleeding in 1.96%. The incidences of wound infection and bile leak both were signiifcantly higher in patients who had had preoperative biliary stenting. None of the patients who had undergone Roux-en-Y hepati-cojejunostomy+retrocolic gastrojejunostomy required any intervention later in their life. CONCLUSIONS:Surgical bypass is a safe procedure with

  19. Vessel Permit System Data Set

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — GARFO issues federal fishing permits annually to owners of fishing vessels who fish in the Greater Atlantic region, as required by federal regulation. These permits...

  20. 2011 Great Lakes Vessel Tracklines

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Automatic Identification Systems (AIS) are a navigation safety device that transmits and monitors the location and characteristics of many vessels in U.S. and...

  1. 2013 East Coast Vessel Tracklines

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Automatic Identification Systems (AIS) are a navigation safety device that transmits and monitors the location and characteristics of many vessels in U.S. and...

  2. SC/OQ Vessel Database

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Data tables holding information for the Surf Clam/Ocean Quahog vessel and dealer/processor logbooks (negative and positive), as well as individual tag information...

  3. Regulation of Blood Vessel Sprouting

    Science.gov (United States)

    Chappell, John C; Wiley, David M; Bautch, Victoria L

    2012-01-01

    Blood vessels are essential conduits of nutrients and oxygen throughout the body. The formation of these vessels involves angiogenic sprouting, a complex process entailing highly integrated cell behaviors and signaling pathways. In this review, we discuss how endothelial cells initiate a vessel sprout through interactions with their environment and with one another, particularly through lateral inhibition. We review the composition of the local environment, which contains an initial set of guidance cues to facilitate the proper outward migration of the sprout as it emerges from a parent vessel. The long-range guidance and sprout stability cues provided by soluble molecules, extracellular matrix components, and interactions with other cell types are also discussed. We also examine emerging evidence for mechanisms that govern sprout fusion with its target and lumen formation. PMID:22020130

  4. Coastal Discard Logbook Survey (Vessels)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — This data set contains data on the type and amount of marine resources that are discarded or interacted with by vessels that are selected to report to the Southeast...

  5. 2011 East Coast Vessel Tracklines

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Automatic Identification Systems (AIS) are a navigation safety device that transmits and monitors the location and characteristics of many vessels in U.S. and...

  6. 2013 West Coast Vessel Tracklines

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Automatic Identification Systems (AIS) are a navigation safety device that transmits and monitors the location and characteristics of many vessels in U.S. and...

  7. Night Blindness and Vitamin A Deficiency following Jejunoilieal Bypass Surgery

    OpenAIRE

    Adams, Paul C; Canny, Christopher L.

    1989-01-01

    A 42-year-old man who developed severe night blindness 15 years following jejunoileal bypass surgery for morbid obesity is described. Ophthamological testing, including dark adaptation, electroretinography and serum vitamin A levels, confirmed a diagnosis of vitamin A deficiency. Oral vitamin A 25,000 iu/day for two months resulted in a full recovery of visual deficits. Nutritional vitamin A deficiency is discussed in the context of intestinal bypass surgery.

  8. Severe peripheral neuropathy following gastric bypass surgery for morbid obesity.

    OpenAIRE

    Maryniak, O.

    1984-01-01

    Severe weakness in the limbs developed in a young woman 3 1/2 months after successful gastric bypass surgery for morbid obesity. Electromyography confirmed the clinical impression of generalized axonal polyneuropathy. Vitamin B replacement therapy was started. The gastric bypass was not reversed, and the patient continued to lose weight while undergoing rehabilitation. After 10 months she had almost fully recovered. Her total weight loss was 76 kg. Neuropathy is an uncommon but serious compli...

  9. Association of sex with patency of femorodistal bypass grafts

    DEFF Research Database (Denmark)

    Watson, H R; Schroeder, T V; Simms, M H;

    2000-01-01

    There is evidence for superior patency in infra-inguinal bypass procedures in men compared to women. A large, prospectively planned series was investigated in order to confirm this finding and to determine the origin of this difference in outcome.......There is evidence for superior patency in infra-inguinal bypass procedures in men compared to women. A large, prospectively planned series was investigated in order to confirm this finding and to determine the origin of this difference in outcome....

  10. Bypass Selection for Control of Heat Exchanger Network

    Institute of Scientific and Technical Information of China (English)

    SUN Lin; LUO Xionglin; HOU Benquan; BAI Yujie

    2013-01-01

    Considering the flexibility and controllability of heat exchanger networks (HENs),bypasses are widely used for effective control of process stream target temperatures.However,the optimal location for the bypass is generally difficult to design with the trade-off between controllability and capital investments.In this paper,based on the steady-state model of heat exchanger networks the optimal bypass location was firstly selected by iteratively calculating the non-square Relative Gain Array (ns-RGA).To simplify the calculation process,rules of bypass selection were also proposed.In order to evaluate this method,then,the structural controllability of heat exchanger networks was analyzed.With both the consideration of the controllability and capital investments,the bypasses locations were finally selected.A case study on the HEN in Crude Distillation Unit was presented in which the ns-RGA and structural controllability were used to select bypasses and also to evaluate the results.

  11. One-dimensional Arterial Network Model for Bypass Grafts Assessment

    CERN Document Server

    Ghigo, Arthur; Wang, Xiaofei; Lagrée, Pierre-Yves; Fullana, Jose-Maria

    2016-01-01

    We propose an arterial network model based on 1D blood hemodynamic equations to study the behavior of different vascular surgical bypass grafts in case of an arterial occlusive pathology: an obliteration or stenosis of the iliac artery. We investigate the performances of three different bypass grafts (Aorto-Femoral, Axillo-Femoral and cross-over Femoral) depending on the degree of obliteration of the stenosis. Numerical simulations show that all bypass grafts are efficient since we retrieve in all cases the normal hemodynamics in the stenosed region while ensuring at the same time a global healthy circulation. We analyze in particular the Axillo-Femoral bypass graft by performing hundreds of simulations by varying the values of the Young's modulus [0.1--50 MPa] and the radius [0.01--5 cm] of the bypass graft. We show that the Young's modulus and radius of commercial bypass grafts are optimal in terms of hemodynamic considerations. The numerical findings prove that this approach could be used to optimize or pl...

  12. Perioperative Changes of Plasma Endothelin-1 in Patients Undergoing Coronary Artery bypass Grafting and the Effect of Nitroglycerin

    Institute of Scientific and Technical Information of China (English)

    陈鑫; 蒋英硕; 徐明; 陈振强; 郭子黄

    2002-01-01

    Objectioe To observe the dynamic changes of the plasma ET-1 and the effect of low dose nitroglycerin in patients with coronary artery bypass surgery. Methods Forty patravenous nitroglycerin 1 μg @ kg-1 @ rain-1 perioperatively. RIA was used to assay the plasma ET-1 lev-el. All the hemodynamie parameters were recorded by the Swan-Ganze catheter. Results The preoperative plasma ET-1 level in patients with coronary artery disease was significantly higher than the normal level. Five minutes after cardiopalmouary bypass in these patients the plasma ET-1 level was increased significantly until 6 to 8 h after operation. The increasing plasma ET-1 level in group B was less intense than that in group A. There was a positive correlation between the plasma ET-1 level and the mean pulmonary artery pressure in group A 2 and 8 h after operation. Conclusion In patients undergoing coronary artery bypass surgery, the increased plasma ET-1 level may be due to the influence of cardiopulmonary bypass partly. Low dose nitroglycerin is beneficial to these patients.

  13. Predictors of atrial fibrillation after coronary artery bypass graft: a meta-analysis

    Institute of Scientific and Technical Information of China (English)

    Liang Yin; Zhi-Nong Wang; Yi-Feng Wang; Wen-Tao Wang; Guang-Yu Ji; Xin-Wei Yang; Zhi-Yun Xu

    2009-01-01

    Objectives Postoperative atrial fibrillation (AF) has been associated with less favorable outcomes in patients undergoing coronary artery bypass graft surgery (CABG) and may result in increased post-operative morbidity and mortality. A systematic review and meta-analysis of published studies was conducted to examine the risk factors of occurrence AF after CABG. Methods Using the Medline database, the Cochrane clinical trials database and online clinical trial databases, we reviewed all randomized controlled trials (RCTs) and observational studies examining the risk factors of occurrence of AF after CABG. We searched for literature published April 2009 or earlier. Results Our review identified 8 studies (observational studies), involving 14548 patients, that examined the risk factors of occurrence of AF after CABG. Although studies provide conflicting results, the overall outcomes suggests that advanced age, previous hypertension, numbers of bridge vessels may increase the occurrence of AF after CABG, while no significant difference of diabetes, preoperative myocardial infarction, and preoperative medication of 13 -Blocker have been observed between the AF patients and no-AF patiens. Conclusions Patients with advanced age, previous hypertension and more numbers of bridge vessels had higher risk for the occurrence of AF after CABG, and perioperative medication and care must be intensified to decrease the postoperative occurrence of AF.

  14. Livstruende underernæring efter gastrisk bypass behandlet med reetablering af normal tarmanatomi

    DEFF Research Database (Denmark)

    Poulsen, Inge Marie; Hansen, Dorte Lindqvist; Grønbæk, Karin Elmegård

    2014-01-01

    reverting the stomach and small intestine into normal anatomy and it was performed without complications so the condition resolved. The malnutrition was probably caused by a mixture of an eating disorder and the effects of the operation influencing gut hormones. It is important to handle this category......We present a case report of a woman who had repeating episodes of severe life-threatening malnutrition four years after a laparoscopic gastric bypass operation for severe overweight. Despite several normal examinations her condition remained unstable. She was offered a laparoscopic operation...

  15. Psychological characteristics and associations with weight outcomes two years after gastric bypass surgery

    DEFF Research Database (Denmark)

    Beck, Nina N; Mehlsen, Mimi; Støving, René Klinkby

    2012-01-01

    This study investigated symptoms of eating disorder, depression, and anxiety among Roux-en-Y gastric bypass patients two years after surgery, and the relationship between these characteristics and weight loss. Respondents completed assessment questionnaires including Eating Disorder Inventory-2...... (EDI-2), Harvard Anxiety and Depression Scale (HADS), and questions related specifically to binge eating. Forty-five patients (8 men, 37 women) out of 65 (67%) responded. Scores were significant higher on impulse regulation, interoceptive awareness, ineffectiveness, maturity fears and interpersonal...... that knowledge of the potential influence of eating disorder symptoms on outcomes after bariatric surgery is needed in order to optimize weight outcomes following surgery....

  16. Post-gastric bypass hypoglycaemia: a review.

    Science.gov (United States)

    Shantavasinkul, Prapimporn C; Torquati, Alfonso; Corsino, Leonor

    2016-07-01

    Bariatric surgery is a highly effective treatment for severe obesity, resulting in substantial weight loss and normalizing obesity-related comorbidities. However, long-term consequences can occur, such as postbariatric surgery hypoglycaemia. This is a challenging medical problem, and the number of patients presenting with it has been increasing. Roux-en-Y gastric bypass (RYGB) is the most popular bariatric procedure, and it is the surgery most commonly associated with the development of postbariatric surgery hypoglycaemia. To date, the pathogenesis of this condition has not been completely established. However, various factors - particularly increased postprandial glucagon-like peptide (GLP)-1 secretion - have been considered as crucial mediator. The mechanisms responsible for diabetic remission after bariatric surgery may be responsible for the development of hypoglycaemia, which typically occurs 1-3 h after a meal and is concurrent with inappropriate hyperinsulinaemia. Carbohydrate-rich foods usually provoke hypoglycaemic symptoms, which can typically be alleviated by strict dietary modifications, including carbohydrate restriction and avoidance of high glycaemic index foods and simple sugars. Few patients require further medical intervention, such as medications, but some patients have required a pancreatectomy. Because this option is not always successful, it is no longer routinely recommended. Clinical trials are needed to further determine the pathophysiology of this condition as well as the best diagnostic and treatment approaches for these patients.

  17. Current status of mini-gastric bypass

    Science.gov (United States)

    Mahawar, Kamal K.; Kumar, Parveen; Carr, William RJ; Jennings, Neil; Schroeder, Norbert; Balupuri, Shlok; Small, Peter K.

    2016-01-01

    Mini-gastric bypass (MGP) is a promising bariatric procedure. Tens of thousands of this procedure have been performed throughout the world since Rutledge performed the first procedure in the United States of America in 1997. Several thousands of these have even been documented in the published scientific literature. Despite a proven track record over nearly two decades, this operation continues to polarise the bariatric community. A large number of surgeons across the world have strong objections to this procedure and do not perform it. The risk of symptomatic (bile) reflux, marginal ulceration, severe malnutrition, and long-term risk of gastric and oesophageal cancers are some of the commonly voiced concerns. Despite these expressed fears, several advantages such as technical simplicity, shorter learning curve, ease of revision and reversal, non-inferior weight loss and comorbidity resolution outcomes have prompted some surgeons to advocate a wider adoption of this procedure. This review examines the current status of these controversial aspects in the light of the published academic literature in English. PMID:27251826

  18. Postoperative abdominal complications after cardiopulmonary bypass

    Directory of Open Access Journals (Sweden)

    Dong Guohua

    2012-10-01

    Full Text Available Abstract Background To summarize the diagnostic and therapeutic experiences on the patients who suffered abdominal complications after cardiovascular surgery with cardiopulmonary bypass(CPB. Methods A total of 2349 consecutive patients submitted to cardiovascular surgery with CPB in our hospital from Jan 2004 to Dec 2010 were involved. The clinical data of any abdominal complication, including its incidence, characters, relative risks, diagnostic measures, medical or surgical management and mortality, was retrospectively analyzed. Results Of all the patients, 33(1.4% developed abdominal complications postoperatively, including 11(33.3% cases of paralytic ileus, 9(27.3% of gastrointestinal haemorrhage, 2(6.1% of gastroduodenal ulcer perforation, 2(6.1% of acute calculus cholecystitis, 3(9.1% of acute acalculus cholecystitis, 4(12.1% of hepatic dysfunction and 2(6.1% of ischemia bowel diseases. Of the 33 patients, 26 (78.8% accepted medical treatment and 7 (21.2% underwent subsequent surgical intervention. There were 5(15.2% deaths in this series, which was significantly higher than the overall mortality (2.7%. Positive history of peptic ulcer, advanced ages, bad heart function, preoperative IABP support, prolonged CPB time, low cardiac output and prolonged mechanical ventilation are the risk factors of abdominal complications. Conclusions Abdominal complications after cardiovascular surgery with CPB have a low incidence but a higher mortality. Early detection and prompt appropriate intervention are essential for the outcome of the patients.

  19. Current status of mini-gastric bypass

    Directory of Open Access Journals (Sweden)

    Kamal K Mahawar

    2016-01-01

    Full Text Available Mini-gastric bypass (MGP is a promising bariatric procedure. Tens of thousands of this procedure have been performed throughout the world since Rutledge performed the first procedure in the United States of America in 1997. Several thousands of these have even been documented in the published scientific literature. Despite a proven track record over nearly two decades, this operation continues to polarise the bariatric community. A large number of surgeons across the world have strong objections to this procedure and do not perform it. The risk of symptomatic (bile reflux, marginal ulceration, severe malnutrition, and long-term risk of gastric and oesophageal cancers are some of the commonly voiced concerns. Despite these expressed fears, several advantages such as technical simplicity, shorter learning curve, ease of revision and reversal, non-inferior weight loss and comorbidity resolution outcomes have prompted some surgeons to advocate a wider adoption of this procedure. This review examines the current status of these controversial aspects in the light of the published academic literature in English.

  20. SUrgical versus PERcutaneous Bypass: SUPERB-trial; Heparin-bonded endoluminal versus surgical femoro-popliteal bypass: study protocol for a randomized controlled trial

    NARCIS (Netherlands)

    Lensvelt, M.M.A.; Holewijn, S.; Fritschy, W.M.; Wikkeling, O.R.; Walraven, L.A. van; Wallis de Vries, B.M.; Zeebregts, C.J.A.; Reijnen, M.M.P.J.

    2011-01-01

    BACKGROUND: Endovascular treatment options for the superficial femoral artery are evolving rapidly. For long lesions, the venous femoropopliteal bypass considered to be superior above the prosthetic bypass. An endoluminal bypass, however, may provide equal patency rates compared to the prosthetic ab

  1. SUrgical versus PERcutaneous Bypass : SUPERB-trial; Heparin-bonded endoluminal versus surgical femoro-popliteal bypass: study protocol for a randomized controlled trial

    NARCIS (Netherlands)

    Lensvelt, Mare M. A.; Holewijn, Suzanne; Fritschy, Wilbert M.; Wikkeling, Otmar R. M.; van Walraven, Laurens A.; de Vries, Bas M. Wallis; Zeebregts, Clark J.; Reijnen, Michel M. P. J.

    2011-01-01

    Background: Endovascular treatment options for the superficial femoral artery are evolving rapidly. For long lesions, the venous femoropopliteal bypass considered to be superior above the prosthetic bypass. An endoluminal bypass, however, may provide equal patency rates compared to the prosthetic ab

  2. HULL GESTURE AND RESISTANCE PREDICTION OF HIGH-SPEED VESSELS*

    Institute of Scientific and Technical Information of China (English)

    NI Chong-ben; ZHU Ren-chuan; MIAO Guo-ping; FAN Ju

    2011-01-01

    Since trim and sinkage are significant while vessels are advancing forward with high speed, the predicted vessel resistance based on restrained model theory or experiment may not be real resistance of vessels during voyage. It is necessary to take the influence of hull gesture into account for oredicting the resistance of high-speed ship. In the present work the resistance problem of high speed ship is treated with the viscous flow theory, and the dynamic mesh technique is adopted to coincide with variation of hull gesture of high speed vessel on voyage. The simulation of the models of S60 ship and a trimaran moving in towing tank with high speed are conducted by using the above theory and technique. The corresponding numerical results are in good agreement with the experimental data. It indicates that the resistance prediction for high speed vessels should take hull gesture into consideration and the dynamic mesh method proposed here is effective in calculating the resistance of high speed vessels.

  3. The use of BDNF to enhance the patency rate of small-diameter tissue-engineered blood vessels through stem cell homing mechanisms.

    Science.gov (United States)

    Zeng, Wen; Wen, Can; Wu, Yangxiao; Li, Li; Zhou, Zhenhua; Mi, Jianhong; Chen, Wen; Yang, Mingcan; Hou, Chunli; Sun, Jiansen; Zhu, Chuhong

    2012-01-01

    The patency rate of small-diameter tissue-engineered blood vessels is the determinant for their application in coronary artery bypass grafting. The coronary artery is innervated by vagus nerves. The origin of vagus nerves is rich in brain-derived neurotrophic factors (BDNF). We have investigated whether BDNF could improve the patency rate of small-diameter tissue-engineered blood vessels through promoting stem cell homing and paracrine activity. In vitro, we isolated early and late endothelial progenitor cells (EPCs) and found BDNF could promote single clone formation and paracrine function of EPCs, and could also induce the proliferation, migration and differentiation of late EPCs. BDNF could enhance the capturing of EPCs in parallel-plate flow chamber. Flow cytometric analysis and laser-scanning confocal microscope showed BDNF could enhance the mobilization and homing of C57BL/6 mouse EPCs after wire injury. Based on it, BDNF was coupled to the lumen surface of the blood vessel matrix material incubated with collagen through SPDP to construct BDNF-modified small-diameter tissue-engineered blood vessel. The blood vessel patency rate was significantly higher than that of control group 8 weeks after implantation in rats and the endothelialization level was superior to control. These results demonstrate that BDNF can effectively improve patency of small-diameter tissue-engineered blood vessels through stem cell homing and paracrine, and it is expected to play an important role in the construction of substitutes for coronary artery bypass grafting.

  4. 46 CFR 169.249 - Pressure vessels.

    Science.gov (United States)

    2010-10-01

    ... 46 Shipping 7 2010-10-01 2010-10-01 false Pressure vessels. 169.249 Section 169.249 Shipping COAST... and Certification Inspections § 169.249 Pressure vessels. Pressure vessels must meet the requirements of part 54 of this chapter. The inspection procedures for pressure vessels are contained in...

  5. 46 CFR 182.330 - Pressure vessels.

    Science.gov (United States)

    2010-10-01

    ... 46 Shipping 7 2010-10-01 2010-10-01 false Pressure vessels. 182.330 Section 182.330 Shipping COAST...) MACHINERY INSTALLATION Auxiliary Machinery § 182.330 Pressure vessels. All unfired pressure vessels must be... unfired pressure vessels must meet the applicable requirements of subchapter F (Marine Engineering)...

  6. Clay Corner: Recreating Chinese Bronze Vessels.

    Science.gov (United States)

    Gamble, Harriet

    1998-01-01

    Presents a lesson where students make faux Chinese bronze vessels through slab or coil clay construction after they learn about the history, function, and design of these vessels. Utilizes a variety of glaze finishes in order to give the vessels an aged look. Gives detailed guidelines for creating the vessels. (CMK)

  7. Annular MHD Physics for Turbojet Energy Bypass

    Science.gov (United States)

    Schneider, Steven J.

    2011-01-01

    The use of annular Hall type MHD generator/accelerator ducts for turbojet energy bypass is evaluated assuming weakly ionized flows obtained from pulsed nanosecond discharges. The equations for a 1-D, axisymmetric MHD generator/accelerator are derived and numerically integrated to determine the generator/accelerator performance characteristics. The concept offers a shockless means of interacting with high speed inlet flows and potentially offers variable inlet geometry performance without the complexity of moving parts simply by varying the generator loading parameter. The cycle analysis conducted iteratively with a spike inlet and turbojet flying at M = 7 at 30 km altitude is estimated to have a positive thrust per unit mass flow of 185 N-s/kg. The turbojet allowable combustor temperature is set at an aggressive 2200 deg K. The annular MHD Hall generator/accelerator is L = 3 m in length with a B(sub r) = 5 Tesla magnetic field and a conductivity of sigma = 5 mho/m for the generator and sigma= 1.0 mho/m for the accelerator. The calculated isentropic efficiency for the generator is eta(sub sg) = 84 percent at an enthalpy extraction ratio, eta(sub Ng) = 0.63. The calculated isentropic efficiency for the accelerator is eta(sub sa) = 81 percent at an enthalpy addition ratio, eta(sub Na) = 0.62. An assessment of the ionization fraction necessary to achieve a conductivity of sigma = 1.0 mho/m is n(sub e)/n = 1.90 X 10(exp -6), and for sigma = 5.0 mho/m is n(sub e)/n = 9.52 X 10(exp -6).

  8. Partial sternotomy coronary surgery with triple-vessel disease in dextrocardia and situs inversus totalis.

    Science.gov (United States)

    Su, Pi Xiong; Gu, Song; Liu, Yan; Gao, Jie

    2013-07-01

    Dextrocardia associated with situs inversus totalis is a rare congenital condition. A small number of cases with these conditions have been reported who underwent myocardial revascularization via the on-pump or off-pump techniques. Among them, only 1 patient with dextrocardia and situs inversus totalis was reported to have the procedure performed with minimally invasive coronary surgery via a right anterior small thoracotomy. However, the case was a single-vessel disease and only one graft was achieved. We describe the case of a 65-year old female patient with triple-vessel obstructive coronary diseases who was successfully revascularized with three grafts using a minimally invasive technique. This was achieved via partial sternotomy and employing off-pump coronary artery bypass grafting.

  9. 46 CFR 116.1120 - Drainage of cockpit vessels, well deck vessels, and open boats.

    Science.gov (United States)

    2010-10-01

    ... 46 Shipping 4 2010-10-01 2010-10-01 false Drainage of cockpit vessels, well deck vessels, and open boats. 116.1120 Section 116.1120 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) SMALL... Drainage of cockpit vessels, well deck vessels, and open boats. Drainage of cockpit vessels, well...

  10. Strategies to prevent intraoperative lung injury during cardiopulmonary bypass

    Directory of Open Access Journals (Sweden)

    Siminelakis Stavros N

    2010-01-01

    Full Text Available Abstract During open heart surgery the influence of a series of factors such as cardiopulmonary bypass (CPB, hypothermia, operation and anaesthesia, as well as medication and transfusion can cause a diffuse trauma in the lungs. This injury leads mostly to a postoperative interstitial pulmonary oedema and abnormal gas exchange. Substantial improvements in all of the above mentioned factors may lead to a better lung function postoperatively. By avoiding CPB, reducing its time, or by minimizing the extracorporeal surface area with the use of miniaturized circuits of CPB, beneficial effects on lung function are reported. In addition, replacement of circuit surface with biocompatible surfaces like heparin-coated, and material-independent sources of blood activation, a better postoperative lung function is observed. Meticulous myocardial protection by using hypothermia and cardioplegia methods during ischemia and reperfusion remain one of the cornerstones of postoperative lung function. The partial restoration of pulmonary artery perfusion during CPB possibly contributes to prevent pulmonary ischemia and lung dysfunction. Using medication such as corticosteroids and aprotinin, which protect the lungs during CPB, and leukocyte depletion filters for operations expected to exceed 90 minutes in CPB-time appear to be protective against the toxic impact of CPB in the lungs. The newer methods of ultrafiltration used to scavenge pro-inflammatory factors seem to be protective for the lung function. In a similar way, reducing the use of cardiotomy suction device, as well as the contact-time between free blood and pericardium, it is expected that the postoperative lung function will be improved.

  11. Vessel enhancing diffusion: a scale space representation of vessel

    NARCIS (Netherlands)

    R. Manniesing (Rashindra); M.A. Viergever; W.J. Niessen (Wiro)

    2006-01-01

    textabstractA method is proposed to enhance vascular structures within the framework of scale space theory. We combine a smooth vessel filter which is based on a geometrical analysis of the Hessian's eigensystem, with a non-linear anisotropic diffusion scheme. The amount and orient

  12. Photovoltaic-module bypass-diode encapsulation. Annual report

    Energy Technology Data Exchange (ETDEWEB)

    1983-06-20

    The design and processing techniques necessary to incorporate bypass diodes within the module encapsulant are presented in this annual report. A comprehensive survey of available pad-mounted PN junction and Schottky diodes led to the selection of Semicon PN junction diode cells for this application. Diode junction-to-heat spreader thermal resistance measurements, performed on a variety of mounted diode chip types and sizes, have yielded values which are consistently below 1/sup 0/C per watt, but show some instability when thermally cycled over the temperature range from -40 to 150/sup 0/C. Based on the results of a detailed thermal analysis, which covered the range of bypass currents from 2 to 20 amperes, three representative experimental modules, each incorporating integral bypass diode/heat spreader assemblies of various sizes, were designed and fabricated. Thermal testing of these modules has enabled the formation of a recommended heat spreader plate sizing relationship. The production cost of three encapsulated bypass diode/heat spreader assemblies were compared with similarly rated externally-mounted packaged diodes. An assessment of bypass diode reliability, which relies heavily on rectifying diode failure rate data, leads to the general conclusion that, when proper designed and installed, these devices will improve the overall reliability of a terrestrial array over a 20 year design lifetime.

  13. The Limit of Large Vessels

    Institute of Scientific and Technical Information of China (English)

    Yang Peiju

    2011-01-01

    On Feb 21(st),the industry was shocked by the news that AP Moller-Maersk placed an order of 10 container ships of 18,000 TEU with the South Korean ship yards.The order brings the development of large vessels to a new climax and at the same time puts forward a series of research subjects to the industry,such as what is the limit for the development of large vessels,whether ship safety can be guaranteed,and etc.

  14. Influence of Preoperative Cerebrovascular Evaluation on Neurological Complications Following Off -Pump Coronary Artery Bypass Grafting%术前脑血管评估对非体外循环冠状动脉旁路移植术后神经系统并发症的影响研究

    Institute of Scientific and Technical Information of China (English)

    许保磊; 毕齐; 陈明盈; 骆迪; 乔秋博

    2016-01-01

    目的 探讨非体外循环冠状动脉旁路移植术 (OPCABG) 后神经系统并发症 (NC) 的发生率及其危险因素, 并明确术前脑灌注异常、 颅脑CT血管成像 ( CTA) 狭窄情况与术后NC的关系. 方法 选取2010年7月—2012年7月北京安贞医院心脏外科连续收治的具有行OPCABG手术指征患者556例, 术前均采用320排动态容积CT评估脑灌注情况, 采用颅脑CTA评估脑血管狭窄情况. 所有患者分别于术前和术后1周进行NC评估, 根据OPCABG后是否发生NC分为NC组 (n=118) 和非NC组 (n=438), 分析脑灌注异常、 颅脑CTA狭窄情况对术后NC的影响. 结果术后 NC 总发生率为 21.2% ( 118/556 ) , 其中脑梗死为1.3% ( 7/556 ) , 缺血低氧性脑病 ( HIE ) 为 2.9%(16/556), 谵妄为1.1% (6/556), 术后认知功能障碍 (POCD) 为11.9% (66/556), 焦虑、 抑郁状态为6.0%(33/556). NC组脑血管病史、 脑灌注异常比例及颅脑CTA狭窄程度均高于非NC组, 差异有统计学意义 ( P<0.05).多因素Logistic回归分析结果显示, 脑血管病史、 术前脑灌注异常为术后NC发生的独立影响因素 ( P<0.05). 多因素Logistic回归分析结果亦显示, 与颅脑CTA 无狭窄患者相比, 重度狭窄患者术后发生NC 的OR ( 95%CI ) 为2.25 (1.35, 3.77), P<0.05. NC组颞叶、 枕叶、 基底核区达峰时间 (TTP) 差值, 枕叶、 基底核区对比剂平均通过时间(MTT) 差值均大于非NC组, 差异有统计学意义 (P<0.05). 结论 OPCABG后NC发生率较高, 脑血管病史、 术前脑灌注异常为术后NC的独立危险因素, 随着颅脑CTA狭窄程度增加, 术后NC的发生风险逐渐增加.%Objective To investigate the incidence and risk factors of neurological complications ( NC) following off-pump coronary artery bypass grafting (OPCABG) .Methods We recruited 556 patients who were admitted into Department of Cardiac Surgery of Beijing Anzhen University and underwent OPCABG there from July 2010 to July 2012.Before

  15. Pulsatile flow characterization in a vessel phantom with elastic wall using ultrasonic particle image velocimetry technique: the impact of vessel stiffness on flow dynamics.

    Science.gov (United States)

    Qian, Ming; Niu, Lili; Wong, Kelvin Kian Loong; Abbott, Derek; Zhou, Qifa; Zheng, Hairong

    2014-09-01

    This study aims to experimentally investigate the impact of vessel stiffness on the flow dynamics of pulsatile vascular flow. Vessel phantoms with elastic walls were fabricated using polyvinyl alcohol cryogel to result in stiffness ranging from 60.9 to 310.3 kPa and tested with pulsatile flows using a flow circulation set-up. Two-dimensional instantaneous and time-dependent flow velocity and shear rate vector fields were measured using ultrasonic particle image velocimetry (EchoPIV). The waveforms of peak velocities measured by EchoPIV were compared with the ultrasonic pulse Doppler spectrum, and the measuring accuracy was validated. The cyclic vessel wall motion and flow pressure were obtained as well. The results showed that vessel stiffening influenced the waveforms resulting from vessel wall distension and flow pressure, and the fields of flow velocity and shear rate. The stiffer vessel had smaller inner diameter variation, larger pulse pressure and median pressure. The velocity and shear rate maximized at peak systole for all vessels. The results showed a decrease in wall shear stress for a stiffer vessel, which can initiate the atherosclerotic process. Our study elucidates the impact of vessel stiffness on several flow dynamic parameters, and also demonstrates the EchoPIV technique to be a useful and powerful tool in cardiovascular research.

  16. Selection of materials for pressure vessels and chemical plants

    Energy Technology Data Exchange (ETDEWEB)

    Huppertz, P.H.; Retter, A. (Linde A.G., Hoellriegelskreuth (Germany, F.R.). Werksgruppe Tieftemperatur und Verfahrenstechnik)

    1980-04-01

    The selection of materials for pressure vessels and chemical plants depends on a number of factors such as operating, operating temperature, operating medium, regulations in force in the country of the plant user concerned and manufacturing possibilities. The essay clearly explains how the above specified factors individually influence the selection of materials. The article also deals with the ranges of application of certain material groups such as unalloyed and low-alloy steels, fine-grained steels, austenitic chromium-nickel steels, unalloyed ferritic chromium steels and other materials. The article closes with remarks on the operational safety of pressure vessels.

  17. Results of bypasses to the anterior tibial artery through the interosseous membrane.

    Science.gov (United States)

    Illuminati, G; Calio, F G; Bertagni, A; Martinelli, V

    1998-08-01

    The purpose of the present study was to retrospectively evaluate the results of anatomically tunneled grafts to the anterior tibial artery for distal revascularization in terms of patency and limb salvage rates as well as local morbidity, which can lengthen the postoperative hospital stay. Twenty-three patients received 24 bypasses to the anterior tibial artery, with grafts tunneled through the interosseous membrane. The mean age was 67 years; 10 patients were diabetic, 12 were smokers, 9 presented with significant coronary artery disease, and 2 with chronic renal insufficiency. The donor vessel was the common femoral artery in 17 cases, the superficial femoral artery in 4, and the infra-articular popliteal artery in 3. The graft material consisted in the reversed saphenous vein in 4 cases, the non-reversed devalvulated ex situ saphenous vein in 11, composite polytetrafluoroethylene (PTFE) + inversed saphenous vein in 6, and PTFE alone in 3 cases. No postoperative mortality was observed, nor was there postoperative graft occlusion or need for major amputation. The average postoperative length of stay in the hospital was 9.7 days. Two local surgical wound complications were observed, which did not necessitate a postoperative hospital stay exceeding 15 days. Cumulative primary patency and limb salvage rates at 3 years were 50% and 70%, respectively. Anatomic tunneling of grafts to the anterior tibial artery yields patency and limb salvage rates comparable to those reported in the literature for distal bypasses and, considered overall, an acceptably low local morbidity and short hospital stay. Definitive superiority over externally tunneled grafts, however, is not definitely demonstrated by this study and should be prospectively tested.

  18. Adenosine Preconditioning versus Ischemic Preconditioning in Patients undergoing Off-Pump Coronary Artery Bypass (OPCAB

    Directory of Open Access Journals (Sweden)

    SeyedKhalil Forouzannia

    2015-10-01

    Full Text Available Background: During off-pump coronary artery bypass (OPCAB, the heart is subjected to ischemic and reperfusion injury. Preconditioning is a mechanism that permits the heart to tolerate myocardial ischemia. The aim of this study was to compare the effects of Adenosine preconditioning with ischemic preconditioning on the global ejection fraction (EF in patients undergoing OPCAB.Methods: In this single-blind, randomized controlled trial, sixty patients undergoing OPCAB were allocated into three equally-numbered groups through simple randomization: Adenosine group, ischemic group, and control group. The patients in the Adenosine group received an infusion of Adenosine. In the ischemic group, ischemic preconditioning was induced by the temporary occlusion of the left anterior descending coronary artery twice for a 2-minute period, followed by 3-minute reperfusion before bypass grafting of the first coronary vessel. The control group received an intravenous infusion of 0.9% saline. Blood samples at different times were sent for the measurement of creatine kinase isoenzyme MB (CK-MB and cardiac troponin I (cTnI. We also recorded electrocardiographic indices and clinical parameters, including postoperative use of inotropic drugs and preoperative and postoperative EF.Results: History of myocardial infarction, hyperlipidemia, diabetes mellitus, kidney disease, preoperative arrhythmias, and utilization of postoperative inotrope was the same between the three groups. The incidence of postoperative arrhythmias was not significant between the three groups. Also, there were no significant differences in preoperative and postoperative EF and the serum levels of enzymes (cTnI and CK-MB between the groups.Conclusion: Based on the findings of this study, there was no significant difference in the postoperative EF between the groups. Although the incidence of arrhythmias was higher in the ischemic preconditioning group than in the other groups, the difference

  19. Neuroprotective Strategies during Cardiac Surgery with Cardiopulmonary Bypass

    Science.gov (United States)

    Salameh, Aida; Dhein, Stefan; Dähnert, Ingo; Klein, Norbert

    2016-01-01

    Aortocoronary bypass or valve surgery usually require cardiac arrest using cardioplegic solutions. Although, in principle, in a number of cases beating heart surgery (so-called off-pump technique) is possible, aortic or valve surgery or correction of congenital heart diseases mostly require cardiopulmonary arrest. During this condition, the heart-lung machine also named cardiopulmonary bypass (CPB) has to take over the circulation. It is noteworthy that the invention of a machine bypassing the heart and lungs enabled complex cardiac operations, but possible negative effects of the CPB on other organs, especially the brain, cannot be neglected. Thus, neuroprotection during CPB is still a matter of great interest. In this review, we will describe the impact of CPB on the brain and focus on pharmacological and non-pharmacological strategies to protect the brain. PMID:27879647

  20. Vitamin deficiency after gastric bypass surgery: a review.

    Science.gov (United States)

    Matrana, Marc R; Davis, William E

    2009-10-01

    More than 60% of the adult US population now meets the criteria for being overweight or obese. Gastric bypass surgery has become a popular and effective way to combat this medical problem. Despite the success of these procedures, they are associated with many complications, including malnutrition, neurological compromise, and vitamin deficiency. Research has determined that even with multivitamin supplementation for life, a large percentage of bypass patients develop vitamin deficiencies. We present a case of beriberi after Roux-en-Y bypass that illustrates the importance of close follow up. A thorough review of vitamin deficiencies in this unique patient population is explored. Vitamin supplementation and treatment recommendations are compiled from the most up-to-date sources. Even patients on regular supplements should be closely monitored for vitamin deficiencies. Patient education regarding vitamin supplementation is vital; it should begin prior to surgery and continue throughout the postoperative period and beyond.

  1. A Comparative Performance Analysis of Low Power Bypassing Array Multipliers

    Directory of Open Access Journals (Sweden)

    Nirlakalla Ravi

    2013-07-01

    Full Text Available Low power design of VLSI circuits has been identified as vital technology in battery powered portable electronic devices and signal processing applications such as Digital Signal Processors (DSP. Multiplier has an important role in the DSPs. Without degrading the performance of the processor, low power parallel multipliers are needed to be design. Bypassing is the widely used technique in the DSPs when the input operand of the multiplier is zero. A Row based Bypassing Multiplier with compressor at the final addition of the ripple carry adder (RCA is designed to focus on low power and high speed. The proposed bypassing multiplier with compressor shows high performance and energy efficiency than Kuo multiplier with Carry Save Adder (CSA at the final RCA.

  2. Rankine cycle load limiting through use of a recuperator bypass

    Science.gov (United States)

    Ernst, Timothy C.

    2011-08-16

    A system for converting heat from an engine into work includes a boiler coupled to a heat source for transferring heat to a working fluid, a turbine that transforms the heat into work, a condenser that transforms the working fluid into liquid, a recuperator with one flow path that routes working fluid from the turbine to the condenser, and another flow path that routes liquid working fluid from the condenser to the boiler, the recuperator being configured to transfer heat to the liquid working fluid, and a bypass valve in parallel with the second flow path. The bypass valve is movable between a closed position, permitting flow through the second flow path and an opened position, under high engine load conditions, bypassing the second flow path.

  3. Proposal of bypass in heat recovery system with sucking air

    Science.gov (United States)

    Siažik, Ján; Malcho, Milan; Rezničák, Štefan

    2016-06-01

    Waste heat is utilized in a wide variety of technologies for a number of reasons. But the significant one such reason is use of the energy contained for example in waste water or waste heat that would otherwise left unused. Other considerable reason it is also reduces primary costs to operate the technology. The article deals with the arrangement section of the unit in heat recovery systems where the entry of waste gases into defluorinastion device. The technologies re-use heat often use the bypass. Bypass fulfill their duty in equipment failures, for example heat exchanger where it is not possible to stop the operationimmediately and the hot combustion gases can flow bypass without interrupting operation.

  4. Grounding Damage to Conventional Vessels

    DEFF Research Database (Denmark)

    Lützen, Marie; Simonsen, Bo Cerup

    2003-01-01

    The present paper is concerned with rational design of conventional vessels with regard to bottom damage generated in grounding accidents. The aim of the work described here is to improve the design basis, primarily through analysis of new statistical data for grounding damage. The current...

  5. Commercial Passenger Fishing Vessel Fishery

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — This data set contains the logbook data from U.S.A. Commercial Passenger Fishing Vessels (CPFV) fishing in the U.S.A. EEZ and in waters off of Baja California, from...

  6. Reactor pressure vessel structural integrity research

    Energy Technology Data Exchange (ETDEWEB)

    Pennell, W.E.; Corwin, W.R. [Oak Ridge National Lab., TN (United States)

    1995-04-01

    Development continues on the technology used to assess the safety of irradiation-embrittled nuclear reactor pressure vessels (RPVs) containing flaws. Fracture mechanics tests on RPV steel, coupled with detailed elastic-plastic finite-element analyses of the crack-tip stress fields, have shown that (1) constraint relaxation at the crack tip of shallows surface flaws results in increased data scatter but no increase in the lower-bound fracture toughness, (2) the nil ductility temperature (NDT) performs better than the reference temperature for nil ductility transition (RT{sub NDT}) as a normalizing parameter for shallow-flaw fracture toughness data, (3) biaxial loading can reduce the shallow-flaw fracture toughness, (4) stress-based dual-parameter fracture toughness correlations cannot predict the effect of biaxial loading on a shallow-flaw fracture toughness because in-plane stresses at the crack tip are not influenced by biaxial loading, and (5) an implicit strain-based dual-parameter fracture toughness correlation can predict the effect of biaxial loading on shallow-flaw fracture toughness. Experimental irradiation investigations have shown that (1) the irradiation-induced shift in Charpy V-notch vs temperature behavior may not be adequate to conservatively assess fracture toughness shifts due to embrittlement, and (2) the wide global variations of initial chemistry and fracture properties of a nominally uniform material within a pressure vessel may confound accurate integrity assessments that require baseline properties.

  7. Reactor vessel lower head integrity

    Energy Technology Data Exchange (ETDEWEB)

    Rubin, A.M.

    1997-02-01

    On March 28, 1979, the Three Mile Island Unit 2 (TMI-2) nuclear power plant underwent a prolonged small break loss-of-coolant accident that resulted in severe damage to the reactor core. Post-accident examinations of the TMI-2 reactor core and lower plenum found that approximately 19,000 kg (19 metric tons) of molten material had relocated onto the lower head of the reactor vessel. Results of the OECD TMI-2 Vessel Investigation Project concluded that a localized hot spot of approximately 1 meter diameter had existed on the lower head. The maximum temperature on the inner surface of the reactor pressure vessel (RPV) in this region reached 1100{degrees}C and remained at that temperature for approximately 30 minutes before cooling occurred. Even under the combined loads of high temperature and high primary system pressure, the TMI-2 RPV did not fail. (i.e. The pressure varied from about 8.5 to 15 MPa during the four-hour period following the relocation of melt to the lower plenum.) Analyses of RPV failure under these conditions, using state-of-the-art computer codes, predicted that the RPV should have failed via local or global creep rupture. However, the vessel did not fail; and it has been hypothesized that rapid cooling of the debris and the vessel wall by water that was present in the lower plenum played an important role in maintaining RPV integrity during the accident. Although the exact mechanism(s) of how such cooling occurs is not known, it has been speculated that cooling in a small gap between the RPV wall and the crust, and/or in cracks within the debris itself, could result in sufficient cooling to maintain RPV integrity. Experimental data are needed to provide the basis to better understand these phenomena and improve models of RPV failure in severe accident codes.

  8. Comprehensive assessment of a post-coronary bypass graft patient with cardiovascular magnetic resonance imaging and multi-detector computed tomography

    Institute of Scientific and Technical Information of China (English)

    Pairoj Rerkpattanapipat; Patcharee Paijitprapaporn; Suthipong Jongjirasiri; Jiraporn Laothamatas; Nithi Mahanonda

    2007-01-01

    Coronary bypass graft surgery (CABG) is a revascularization procedure which reduces myocardial ischemia and cardiovascular morbidity and mortality in selected patients; however, up to 40% of saphanous vein grafts may degenerate over 10 years. Although coronary angiography is the gold standard to detect graft patency and native vessel disease, sometimes it is difficult to locate the grafts resulting in increased exposure to radiation and contrast administration. This case highlights the utility of cardiac computerized tomography and magnetic resonance imaging to provide comprehensive noninvasive assessment in a patient post CABG.

  9. Fibrin Adhesive: Clinical Application in Coronary Artery Bypass Graft Surgery

    Science.gov (United States)

    Fundaró, Pino; Velardi, Antonio R.; Santoli, Carmine

    1985-01-01

    Fibrin adhesive was used 72 times in a group of 67 patients undergoing elective coronary artery bypass graft surgery. The indications were prophylactic sealing of potential sources of bleeding, topical hemostasis (control of bleeding sites dangerous or difficult to suture), and fixation of the graft in the optimal position. The method of glue application under varying circumstances is described and the results are reported. This experience suggests that in some cases the glue expedites the operation and makes it safer. We conclude that the fibrin sealing represents a valid aid in coronary artery bypass graft surgery. PMID:15227018

  10. Obstetrical and neonatal outcomes in women following gastric bypass

    DEFF Research Database (Denmark)

    Berlac, Janne Foss; Skovlund, Charlotte Wessel; Lidegaard, Ojvind

    2014-01-01

    more admissions to neonatal intensive care unit compared with newborn of normal weight mothers; RR = 1.5 (1.1-2.0). CONCLUSIONS: Gastric bypass may reduce the risk of preeclampsia, emergency cesarean section, and perinatal asphyxia, compared with adipose women without surgery. Compared with normal...... weight controls women who had had a gastric bypass had a higher risk of hypertension, gestational diabetes, and acute abdominal pain during pregnancy and their children a lower birthweight and higher incidence of admittance to neonatal intensive care....

  11. [Prevalence of early and late dumping after gastric bypass].

    Science.gov (United States)

    Héraïef, R; Giusti, V

    2014-03-26

    Gastric bypass surgery is an effective treatment of obesity, bringing a significant weight loss and a major improvement of carbohydrate profile. However, in some patients, a deregulation in carbohydrate metabolism between insulin secretion and sensitivity is observed, whereupon early and late dumping happen. Their prevalence isn't well studied, although it seems that 10 to 20% of patients are affected. We've studied a cohort of 70 patients who undergone gastric bypass surgery at the CHUV. 18 (25.7%) patients have a positive anamnesis for early dumping and 10 (14.3%) for late dumping, being it superior as what is described in the literature.

  12. Dextrocardia with situs inversus totalis: coronary artery bypass grafting.

    Science.gov (United States)

    Hashmi, Salila; Anis, Mariam; Darr, Umer

    2012-01-01

    Dextrocardia with situs inversus is a rare congenital abnormality involving a left-handed mal rotation of the visceral organs. The incidence of coronary artery disease is the same as that in the general population. Performing coronary artery bypass surgery on patients with dextrocardia poses a more challenging task. It is recommended that the right internal mammary artery be the first choice of graft for the anterior descending artery for a "situs inversus" situation. We report 2 cases of patients with Dextrocardia who developed coronary artery disease and underwent coronary artery bypass grafting. Also mentioned is the slight difference in our technique.

  13. Vessel tree extraction using locally optimal paths

    DEFF Research Database (Denmark)

    Lo, Pechin Chien Pau; van Ginneken, Bram; de Bruijne, Marleen

    2010-01-01

    This paper proposes a method to extract vessel trees by continually extending detected branches with locally optimal paths. Our approach uses a cost function from a multi scale vessel enhancement filter. Optimal paths are selected based on rules that take into account the geometric characteristics...... of the vessel tree. Experiments were performed on 10 low dose chest CT scans for which the pulmonary vessel trees were extracted. The proposed method is shown to extract a better connected vessel tree and extract more of the small peripheral vessels in comparison to applying a threshold on the output...

  14. Tidlige erfaringer med duplexovervågning af femoropopliteale og -krurale vene-bypass

    DEFF Research Database (Denmark)

    Nielsen, Tina G; von Jessen, Frants; Schroeder, T V

    1993-01-01

    Identification and correction of graft stenoses in femoropopliteal and -crural vein bypasses can prevent reconstruction failure. Sixty six consecutive vein bypasses entered a postoperative surveillance protocol, which implied clinical assessment, measurement of ankle blood pressure and duplex-sca...

  15. Managing the Inflammatory Response after Cardiopulmonary Bypass : Review of the Studies in Animal Models

    NARCIS (Netherlands)

    Liguori, Gabriel Romero; Kanas, Alexandre Fligelman; Moreira, Luiz Felipe Pinho

    2014-01-01

    OBJECTIVE: To review studies performed in animal models that evaluated therapeutic interventions to inflammatory response and microcirculatory changes after cardiopulmonary bypass. METHODS: It was used the search strategy ("Cardiopulmonary Bypass" (MeSH)) and ("Microcirculation" (MeSH) or "Inflammat

  16. Off-pump coronary artery bypass grafting in patients with mirror-imaging dextrocardia.

    Science.gov (United States)

    Yuan, Xin; Sun, Hansong; Wang, Xianqiang

    2015-08-01

    Dextrocardia requires alterations in techniques during coronary artery bypass graft (CABG) surgery. We report two cases undergoing off-pump coronary artery bypass graft (OPCAB) surgery and discuss techniques for the operative management of these patients.

  17. Preliminary studies of coolant by-pass flows in a prismatic very high temperature reactor using computational fluid dynamics

    Energy Technology Data Exchange (ETDEWEB)

    Hiroyuki Sato; Richard Johnson; Richard Schultz

    2009-09-01

    Three dimensional computational fluid dynamic (CFD) calculations of a typical prismatic very high temperature gas-cooled reactor (VHTR) were conducted to investigate the influence of gap geometry on flow and temperature distributions in the reactor core using commercial CFD code FLUENT. Parametric calculations changing the gap width in a whole core length model of fuel and reflector columns were performed. The simulations show the effects of core by-pass flows in the heated core region by comparing results for several gap widths including zero gap width. The calculation results underline the importance of considering inter-column gap width for the evaluation of maximum fuel temperatures and temperature gradients in fuel blocks. In addition, it is shown that temperatures of core outlet flow from gaps and channels are strongly affected by the gap width of by-pass flow in the reactor core.

  18. Consequences of material effects on in-vessel retention

    Energy Technology Data Exchange (ETDEWEB)

    Seiler, Jean Marie [CEA Grenoble, DTN/SE2T/LPTM, 17 rue des Martyrs, 38054 Grenoble Cedex 9 (France); Tourniaire, Bruno [CEA Grenoble, DTN/SE2T/LPTM, 17 rue des Martyrs, 38054 Grenoble Cedex 9 (France)]. E-mail: bruno.tourniaire@cea.fr; Defoort, Francoise [CEA Grenoble, DTN/SE2T/LPTM, 17 rue des Martyrs, 38054 Grenoble Cedex 9 (France); Froment, Karine [CEA Grenoble, DTN/SE2T/LPTM, 17 rue des Martyrs, 38054 Grenoble Cedex 9 (France)

    2007-09-15

    In-vessel retention (IVR) consists in cooling the corium contained in the reactor vessel by natural convection and reactor cavity flooding. This strategy of severe accident management enables the corium to be kept inside the second confinement barrier: the reactor vessel. The general approach which is used to study IVR problems is a 'bounding' approach which consists in assuming a specified corium stratification in the vessel and then demonstrating that the vessel can cope with the resulting thermal and mechanical loads. Thermal loading on the vessel is controlled by the convective heat transfer inside the molten corium in the lower head. If there is no water in the vessel and if the corium pool is overlaid by a liquid steel layer, then the heat flux might focus on the vessel in front of the steel layer ('focusing effect') and exceed the dry-out heat flux (CHF or DHF). One of the critical points of these studies is linked to the determination of the height of the molten steel layer that can stratify above the oxidic pool. The MASCA experiments have highlighted that part of molten steel may stratify under the oxidic corium which reduces the thickness of the steel layer on top of the pool. This behavior can be explained by chemical interaction between the oxide and metallic phases of the pool which confirms that these materials cannot be treated as inert species. Following these conclusions, a methodology which couples physicochemical effects and thermalhydraulics has been developed to address the IVR issue. The main purpose of this paper is to present this methodology and its application for given corium mass inventories. Attention focuses on the influence of parameters such as the ratio U/Zr and oxidation ratio of zirconia. For a 1000 MW PWR, approximately 10 t of steel stratify at the bottom of the vessel for 40% Zr oxidation, and 25 t for 30% Zr oxidation. This leads to a 25-50% increase of the mass of molten steel that is required for

  19. Hereditary spherocytosis in a patient undergoing coronary artery bypass grafting with cardiopulmonary bypass--a case report.

    Science.gov (United States)

    Spegar, J; Riha, H; Kotulak, T; Vanek, T

    2015-01-01

    Hereditary spherocytosis is a genetically determined abnormality of red blood cells. It is the most common cause of inherited haemolysis in Europe and North America within the Caucasian population. We document a patient who underwent an aortocoronary bypass procedure on cardiopulmonary bypass. In view of the uncertain tolerance of the abnormal red cells in hereditary spherocytosis to cardiopulmonary bypass, we reviewed the patient's chart and analyzed recorded values of these parameters: free plasma haemoglobin, renal parameters, cystatin C, bilirubin, liver tests, urine samples. From the results, we can see that slight haemolysis-elevated bilirubin in the blood sample and elevated bilirubin and urobilinogen in the urine sample occurred on the first postoperative day. The levels of these parameters slowly decreased during the next postoperative days. There was no real clinical effect of this haemolysis on renal functions.

  20. P/Q-type and T-type voltage-gated calcium channels are involved in the contraction of mammary and brain blood vessels from hypertensive patients

    DEFF Research Database (Denmark)

    Thuesen, A D; Lyngsø, K S; Rasmussen, L

    2017-01-01

    AIM: Calcium channel blockers are widely used in cardiovascular diseases. Besides L-type channels, T- and P/Q-type calcium channels are involved in the contraction of human renal blood vessels. It was hypothesized that T- and P/Q-type channels are involved in the contraction of human brain...... and mammary blood vessels. METHODS: Internal mammary arteries from bypass surgery patients and cerebral arterioles from patients with brain tumours with and without hypertension were tested in a myograph and perfusion set-up. PCR and immunohistochemistry were performed on isolated blood vessels. RESULTS......: The P/Q-type antagonist ω-agatoxin IVA (10(-8) mol L(-1) ) and the T-type calcium blocker mibefradil (10(-7) mol L(-1) ) inhibited KCl depolarization-induced contraction in mammary arteries from hypertensive patients with no effect on blood vessels from normotensive patients. ω-Agatoxin IVA decreased...

  1. Cavitation damage prediction for the JSNS mercury target vessel

    Science.gov (United States)

    Naoe, Takashi; Kogawa, Hiroyuki; Wakui, Takashi; Haga, Katsuhiro; Teshigawara, Makoto; Kinoshita, Hidetaka; Takada, Hiroshi; Futakawa, Masatoshi

    2016-01-01

    The liquid mercury target system for the Japan Spallation Neutron Source (JSNS) at the Materials and Life science experimental Facility (MLF) in the Japan Proton Accelerator Research Complex (J-PARC) is designed to produce pulsed neutrons. The mercury target vessel in this system, which is made of type 316L stainless steel, is damaged by pressure wave-induced cavitation due to proton beam bombardment. Currently, cavitation damage is considered to be the dominant factor influencing the service life of the target vessel rather than radiation damage. In this study, cavitation damage to the interior surface of the target vessel was predicted on the basis of accumulated damage data from off-beam and on-beam experiments. The predicted damage was compared with the damage observed in a used target vessel. Furthermore, the effect of injecting gas microbubbles on cavitation damage was predicted through the measurement of the acoustic vibration of the target vessel. It was shown that the predicted depth of cavitation damage is reasonably coincident with the observed results. Moreover, it was confirmed that the injection of gas microbubbles had an effect on cavitation damage.

  2. 21 CFR 870.4410 - Cardiopulmonary bypass in-line blood gas sensor.

    Science.gov (United States)

    2010-04-01

    ... 21 Food and Drugs 8 2010-04-01 2010-04-01 false Cardiopulmonary bypass in-line blood gas sensor... Cardiopulmonary bypass in-line blood gas sensor. (a) Identification. A cardiopulmonary bypass in-line blood gas sensor is a transducer that measures the level of gases in the blood. (b) Classification. Class...

  3. Fabrication of nanofiber non-wovens on the melt blowing die with air by-passes

    Directory of Open Access Journals (Sweden)

    Chen Ting

    2016-01-01

    Full Text Available The air flow field of the melt blowing die with air by-passes is simulated. The results show that fibers fabricated on the die with air by-passes are much finer than those without air by-passes, which indicates an energy-saving approach to fabricating nanofibers on the melt blowing equipment.

  4. Fabrication of nanofiber non-wovens on the melt blowing die with air by-passes

    OpenAIRE

    Chen Ting; Yang Kang; Wu Li-Li

    2016-01-01

    The air flow field of the melt blowing die with air by-passes is simulated. The results show that fibers fabricated on the die with air by-passes are much finer than those without air by-passes, which indicates an energy-saving approach to fabricating nanofibers on the melt blowing equipment.

  5. On-Pump Versus Off-Pump Coronary Artery Bypass Surgery in Elderly Patients

    DEFF Research Database (Denmark)

    Holme, Susanne Juel; Houlind, Kim; Kjeldsen, Bo Juul;

    2012-01-01

    Conventional coronary artery bypass grafting performed with the use of cardiopulmonary bypass is a well-validated treatment for patients with ischemic heart disease. Off-pump coronary artery bypass grafting (OPCAB) has been suggested to reduce the number of perioperative complications, especially...... in elderly patients....

  6. Natural headland sand bypassing; towards identifying and modelling the mechanisms and processes

    NARCIS (Netherlands)

    Bin Ab Razak, M.S.

    2015-01-01

    Natural headland sand bypassing: Towards identifying and modelling the mechanisms and processes contributes to the understanding of the mechanisms and processes of sand bypassing in artificial and non-artificial coastal environments through a numerical modelling study. Sand bypassing processes in ge

  7. On-pump versus off-pump coronary artery bypass surgery

    DEFF Research Database (Denmark)

    Houlind, Kim Christian

    2013-01-01

    Off pump coronary artery bypass surgery has been purported to be safer than conventional coronary artery bypass surgery performed using cardiopulmonary bypass. This theory was supported by a number of early series, but failed to be confirmed by a number of small, randomized controlled trials . Co...

  8. 21 CFR 870.4210 - Cardiopulmonary bypass vascular catheter, cannula, or tubing.

    Science.gov (United States)

    2010-04-01

    ... Devices § 870.4210 Cardiopulmonary bypass vascular catheter, cannula, or tubing. (a) Identification. A cardiopulmonary bypass vascular catheter, cannula, or tubing is a device used in cardiopulmonary surgery to... 21 Food and Drugs 8 2010-04-01 2010-04-01 false Cardiopulmonary bypass vascular catheter,...

  9. Patient Bypass Behavior and Critical Access Hospitals: Implications for Patient Retention

    Science.gov (United States)

    Liu, Jiexin (Jason); Bellamy, Gail R.; McCormick, Melissa

    2007-01-01

    Purpose: To assess the extent of bypass for inpatient care among patients living in Critical Access Hospital (CAH) service areas, and to determine factors associated with bypass, the reasons for bypass, and what CAHs can do to retain patients locally. Methods: Six hundred and forty-seven subjects, aged 18 years and older, who had been admitted to…

  10. Uncooled infrared camera for the noninvasive visualization of the vascular flow in an anastomotic vessel during neurological surgery: technical note.

    Science.gov (United States)

    Otani, Naoki; Ishihara, Miya; Nakai, Kanji; Fujita, Masanori; Wada, Kojiro; Mori, Kentaro

    2014-06-17

    We herein present our experience to assess intraoperative confirmation of vascular patency with an uncooled infrared camera in extracranial-intracranial (EC-IC) bypass surgery. This camera had distinguishing characteristics, including its small size, light weight, and adequate temperature resolution (camera to assess the vascular flow of the end-to-side anastomosis model in rats. In addition, we evaluated the vascular flow in continuous clinical series using this infrared camera during EC-IC bypass in 14 patients (17 sides). This infrared camera offers real-time information on the vascular patency of end-to-side anastomosis vessels of all relevant diameters. The spatial resolution and image quality are satisfactory, and the procedure can be safely repeatable. We have shown that the infrared camera could be a new and feasible technology for intraoperative imaging of the vascular flow and is considered to be clinically useful during cerebrovascular surgery.

  11. US Virgin Islands Abandoned Vessel Inventory

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — NOAA Abandoned Vessel Project Data for US Virgin Islands. Abandoned vessels pose a significant threat to the NOAA Trust resources through physical destruction of...

  12. Hawaii Abandoned Vessel Inventory, Kure, NWHI

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — NOAA Abandoned Vessel Project Data for Kure, NWHI. Abandoned vessels pose a significant threat to the NOAA Trust resources through physical destruction of coral...

  13. Hawaii Abandoned Vessel Inventory, Maro Reef, NWHI

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — NOAA Abandoned Vessel Project Data for Maro Reef, NWHI. Abandoned vessels pose a significant threat to the NOAA Trust resources through physical destruction of coral...

  14. Hawaii Abandoned Vessel Inventory, Lisianski Island, NWHI

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — NOAA Abandoned Vessel Project Data for Lisianski Island, NWHI. Abandoned vessels pose a significant threat to the NOAA Trust resources through physical destruction...

  15. AFSC/FMA/Vessel Assessment Logging

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Vessels fishing trawl gear, vessels fishing hook-and-line and pot gear that are also greater than 57.5 feet overall, and shoreside and floating processing facilities...

  16. 2013 EPA Vessels General Permit (VGP)

    Data.gov (United States)

    U.S. Environmental Protection Agency — Information for any vessel that submitted a Notice of Intent (NOI), Notice of Termination (NOT), or annual report under EPA's 2013 Vessel General Permit (VGP)....

  17. Hawaii Abandoned Vessel Inventory, Hawaii Island

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — NOAA Abandoned Vessel Project Data for Hawaii Island. Abandoned vessels pose a significant threat to the NOAA Trust resources through physical destruction of coral...

  18. Hawaii Abandoned Vessel Inventory, Midway Island, NWHI

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — NOAA Abandoned Vessel Project Data for Midway Island, NWHI. Abandoned vessels pose a significant threat to the NOAA Trust resources through physical destruction of...

  19. Using Vessel Monitoring System Data to Identify and Characterize Trips Made by Fishing Vessels in the United States North Pacific

    Science.gov (United States)

    Haynie, Alan C.

    2016-01-01

    Time spent fishing is the effort metric often studied in fisheries but it may under-represent the effort actually expended by fishers. Entire fishing trips, from the time vessels leave port until they return, may prove more useful for examining trends in fleet dynamics, fisher behavior, and fishing costs. However, such trip information is often difficult to resolve. We identified ~30,000 trips made by vessels that targeted walleye pollock (Gadus chalcogrammus) in the Eastern Bering Sea from 2008–2014 by using vessel monitoring system (VMS) and landings data. We compared estimated trip durations to observer data, which were available for approximately half of trips. Total days at sea were estimated with 5 million VMS records (timestamps and vessel locations), this study was as much about understanding and managing data errors as it was about characterizing trips. Missing VMS records were pervasive and they strongly influenced our approach. To understand implications of missing data on inference, we simulated removal of VMS records from trips. Removal of records straightened (i.e., shortened) vessel trajectories, and travel distances were underestimated, on average, by 1.5–13.4% per trip. Despite this bias, VMS proved robust for trip characterization and for improved quality control of human-recorded data. Our scrutiny of human-reported and VMS data advanced our understanding of the potential utility and challenges facing VMS users globally. PMID:27788174

  20. Transit-time flow measurement as a predictor of coronary bypass graft failure at one year angiographic follow-up

    DEFF Research Database (Denmark)

    Lehnert, Per; Møller, Christian H; Damgaard, Sune;

    2015-01-01

    on graft vessel type, anastomatic configuration, and coronary artery size. RESULTS: Nine hundred eighty-two coronary anastomoses were performed of which 12% had signs of graft failure at one year angiographic follow-up. In internal mammary arteries (IMAs), analysis showed a 4% decrease in graft failure......BACKGROUND: Transit-time flow measurement (TTFM) is a commonly used intraoperative method for evaluation of coronary artery bypass graft (CABG) anastomoses. This study was undertaken to determine whether TTFM can also be used to predict graft patency at one year postsurgery. METHODS: Three hundred...... forty-five CABG patients with intraoperative graft flow measurements and one year angiographic follow-up were analyzed. Graft failure was defined as more than 50% stenosis including the "string sign." Logistic regression analysis was used to analyze the risk of graft failure after one year based...

  1. [Coronary artery bypass surgery: methods of performance monitoring and quality control].

    Science.gov (United States)

    Albert, A; Sergeant, P; Ennker, J

    2009-10-01

    The strength of coronary bypass operations depends on the preservation of their benefits regarding freedom of symptoms, quality of life and survival, over decades. Significant variability of the results of an operative intervention according to the hospital or the operating surgeon is considered a weakness in the procedure. The external quality insurance tries to reach a transparent service providing market through hospital ranking comparability. Widely available information and competition will promote the improvement of the whole quality. The structured dialog acts as a control instrument for the BQS (Federal Quality Insurance). It is launched in case of deviations from the standard references or statistically significant differences between the results of the operations in any hospital and the average notational results. In comparison to the external control the hospital internal control has greater ability to reach a medically useful statement regarding the results of the treatment and to correct the mistakes in time. An online information portal based on a departmental databank (DataWarehouse, DataMart) is an attractive solution for the physician in order to get transparently and timely informed about the variability in the performance.The individual surgeon significantly influences the short- and long-term treatment results. Accordingly, selection, targeted training and performance measurements are necessary.Strict risk management and failure analysis of individual cases are included in the methods of internal quality control aiming to identify and correct the inadequacies in the system and the course of treatment. According to the international as well as our own experience, at least 30% of the mortalities after bypass operations are avoidable. A functioning quality control is especially important in minimally invasive interventions because they are often technically more demanding in comparison to the conventional procedures. In the field of OPCAB surgery

  2. Emergency EC-IC bypass for symptomatic atherosclerotic ischemic stroke.

    Science.gov (United States)

    Horiuchi, Tetsuyoshi; Nitta, Junpei; Ishizaka, Shigetoshi; Kanaya, Kohei; Yanagawa, Takao; Hongo, Kazuhiro

    2013-10-01

    Previous studies have shown that extracranial-intracranial (EC-IC) bypass surgery has no preventive effect on subsequent ipsilateral ischemic stroke in patients with symptomatic atherosclerotic internal carotid occlusion and hemodynamic cerebral ischemia. A few studies have assessed whether an urgent EC-IC bypass surgery is an effective treatment for main trunk stenosis or occlusion in acute stage. The authors retrospectively reviewed 58 consecutive patients who underwent urgent EC-IC bypass for symptomatic internal carotid artery or the middle cerebral artery stenosis or occlusion between January 2003 and December 2011. Clinical characteristics and neuroimagings were evaluated and analyzed. Based on preoperative angiogram, responsible lesions were the internal carotid artery in 19 (32.8%) patients and the middle cerebral artery in 39 (67.2%). No hemorrhagic complication occurred. Sixty-nine percent of patients showed improvement of neurological function after surgery, and 74.1% of patients had favorable outcome. Unfavorable outcome was associated with insufficient collateral flow and new infarction after bypass surgery.

  3. Emergency bypass post percutaneous atrial ablation: a case report.

    LENUS (Irish Health Repository)

    Hargrove, M

    2010-11-01

    A 34-year-old male undergoing percutaneous atrial ablation procedure for paroxysmal fibrillation required emergency sternotomy for cardiac tamponade. The patient had been anticoagulated and had received plavix and aspirin prior to and during the ablation procedure. Seven units of red cell concentrate had been transfused in the cardiac catherisation laboratory. On arrival in theatre, the patient was hypotensive, but was awake on induction of anaesthesia. No recordable blood pressure with non-invasive monitoring was observed. A sternotomy was immediately performed and, on evacuation of the pericardium, a bleeding site was not visible. The patient was commenced on cardiopulmonary bypass. Bleeding site was identified and the defect closed. The patient was weaned from cardiopulmonary bypass with minimal inotropic support and made an uneventful recovery. Bypass time was 38 minutes. A literature review showed a 1% incidence of post-ablation bleeding(1). The incidence of reverting to bypass for such an event has not been reported previously. During these procedures, it might be wise to have the cardiothoracic team notified while atrial ablation procedures are being performed in the cardiac catheterization laboratory.

  4. 21 CFR 870.4350 - Cardiopulmonary bypass oxygenator.

    Science.gov (United States)

    2010-04-01

    ... 21 Food and Drugs 8 2010-04-01 2010-04-01 false Cardiopulmonary bypass oxygenator. 870.4350 Section 870.4350 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES... gases between blood and a gaseous environment to satisfy the gas exchange needs of a patient during...

  5. Bypassing of a barrier by dissociated and superlattice dislocations

    DEFF Research Database (Denmark)

    Bhushan, Karihaloo

    1975-01-01

    Very simple procedures are used to calculate the upper and lower bounds for the applied stress required for the leading extended (superlattice) dislocation in a group of n coplanar screw dislocations of like sign with Burgers vector b to bypass a noncoplanar perfect screw dislocation with Burgers...... vector mb (m...

  6. Polarization for the by-pass SLAC/PEP collider

    Energy Technology Data Exchange (ETDEWEB)

    Chao, A.W.

    1980-06-01

    It was suggested that one can collide the store e/sup +/ beam in PEP with the e/sup /minus// beam from SLAC to reach a center-of-mass energy higher than that achieved by the PEP colliding beams. Although the future of this PEP/SLAC collider is not yet certain, it is useful to first explore its physics possibilities. One possible version of the SLAC/PEP collider utilizes a by-pass at the interaction point; the stored beam is displaced vertically by a set of vertical bending magnets every time the linac beam arrives. One feature of this by-pass scheme that makes it attractive is that the amount of the vertical displacement of the by-pass can be chosen so that the spin polarization of the stored beam is made longitudinal at the point of interaction. In this note, we have studied the various depolarization effects of the stored e/sup +/ beam due to the perturbation of the by-pass magnets. 1 fig.

  7. Prediction of bypass transition with differential Reynolds stress models

    NARCIS (Netherlands)

    Westin, K.J.A.; Henkes, R.A.W.M.

    1998-01-01

    Boundary layer transition induced by high levels of free stream turbulence (FSl), so called bypass transition, can not be predicted with conventional stability calculations (e.g. the en-method). The use of turbulence models for transition prediction has shown some success for this type of flows, and

  8. Blood concentrations of cefuroxime in cardiopulmonary bypass surgery

    NARCIS (Netherlands)

    Bertholee, Daphne; ter Horst, Peter G. J.; Hijmering, Michel L.; Spanjersberg, Alexander J.; Hospes, Wobbe; Wilffert, Bob

    2013-01-01

    Objectives Patients with coronary artery bypass graft (CABG) surgery are at risk for severe postoperative infections. Prophylactic cefuroxime may help to reduce this risk, however sufficient concentrations, i.e. above the breakpoint (32 mg/L), are mandatory. The aim of this study is to evaluate the

  9. Gastrointestinal motility during cardiopulmonary bypass : A sonomicrometric study

    NARCIS (Netherlands)

    Gu, YJ; de Kroon, TL; Elstrodt, JM; Rakhorst, G

    2006-01-01

    Cardiopulmonary bypass (CPB) is known to impair the integrity of the gastrointestinal tract. However, little is known about the movement behavior of the gastrointestinal tract during CPB. This study was aimed to assess the gastrointestinal motility with sonomicrometry, a distance measurement using u

  10. Fabric heart retractor for coronary artery bypass operations.

    Science.gov (United States)

    Kazama, S; Ishihara, A

    1993-06-01

    A new device for heart retraction during coronary artery bypass operations has been developed. It provides safe and steady support and an unobstructed view of the lateral, posterior, and inferior surfaces of the heart; in addition, it is easy to handle.

  11. Pathophysiology and treatment of edema following femoropopliteal bypass surgery

    NARCIS (Netherlands)

    te Slaa, A.; Dolmans, D. E. J. G. J.; Ho, G. H.; Moll, F. L.; van der Laan, L.

    2012-01-01

    Substantial lower-limb edema affects the majority of patients who undergo peripheral bypass surgery. Edema has impairing effects on the microvascular and the macrovascular circulation, causes discomfort and might delay the rehabilitation process of the patient. However, the pathophysiology of this e

  12. Clinical benefit of steroid use in patients undergoing cardiopulmonary bypass

    DEFF Research Database (Denmark)

    Whitlock, Richard P; Chan, Simon; Devereaux, P J;

    2008-01-01

    We sought to establish the efficacy and safety of prophylactic steroids in adult patients undergoing cardiopulmonary bypass (CPB). We performed a meta-analysis of randomized trials reporting the effects of prophylactic steroids on clinical outcomes after CPB. Outcomes examined were mortality...

  13. 46 CFR 119.330 - Pressure vessels.

    Science.gov (United States)

    2010-10-01

    ... 46 Shipping 4 2010-10-01 2010-10-01 false Pressure vessels. 119.330 Section 119.330 Shipping COAST... Machinery § 119.330 Pressure vessels. All unfired pressure vessels must be installed to the satisfaction of the cognizant OCMI. The design, construction, and original testing of such unfired pressure...

  14. Photoacoustic determination of blood vessel diameter.

    NARCIS (Netherlands)

    Kolkman, R.G.; Klaessens, J.H.G.M.; Hondebrink, E.; Hopman, J.C.W.; Mul, F.F. de; Steenbergen, W.; Thijssen, J.M.; Leeuwen, T.G. van

    2004-01-01

    A double-ring sensor was applied in photoacoustic tomographic imaging of artificial blood vessels as well as blood vessels in a rabbit ear. The peak-to-peak time (tau(pp)) of the laser (1064 nm) induced pressure transient was used to estimate the axial vessel diameter. Comparison with the actual ves

  15. Is there an association between urolithiasis and roux-en-y gastric bypass surgery?

    Directory of Open Access Journals (Sweden)

    Andre Costa-Matos

    2009-08-01

    Full Text Available Purpose: Several studies have documented high incidence of urinary lithiasis after jejunoileal by-pass. Roux-en-y gastric bypass surgery (RYGB is currently the most common bariatric procedure. Because of its difficult for absorption, RYGB has a potential risk to increase the incidence of lithiasis. This study was conducted in order to test the hypothesis that RYGB increases the incidence urolithiasis after 50% of excessive weight loss. Materials and Methods: We performed a retrospective cohort study to evaluate 58 patients who underwent RYGB at the Obesity Service at Santa Casa de Misericordia de Sao Paulo, between 2000 and 2005, with minimum follow-up of 10 and maximum of 72 months, after the procedure. Results: Forty-five (77.6% patients had ≥ 50% loss of weight excess. There was no difference between the frequency of urolithiasis before and after the procedure, and nephrolithiasis was observed after surgery in only one patient, however this had been detected before the procedure. Conclusion: In the period studied, RYGB does not seem to affect the incidence of urolithiasis after weight reduction. This may be due to its smaller malabsorptive component as compared with jejunoileal “by-pass”, thereby possibly not significantly influencing the oxalate metabolism.

  16. Influence Factors of Nuclear Power Plant Reactor Pressure Vessel on Irradiation Embrittlement%反应堆压力容器钢辐照脆化的影响因素分析

    Institute of Scientific and Technical Information of China (English)

    王荣山; 徐超亮; 刘向兵; 黄平; 陈骏; 李承亮

    2014-01-01

    压力容器(RPV)在工况条件下经中子辐照后将导致力学性能退化,发生辐照脆化现象。相关研究表明,引起 RPV 钢辐照脆化的因素包括自身材料因素和服役环境因素。材料因素是 RPV 钢自身性质对辐照脆化的影响,包括材料化学成分、微观组织特性与晶粒尺寸,环境因素是 RPV 服役环境对辐照脆化的影响,包括中子注量、中子注量率、中子能谱和辐照温度。%The performance degradation of nuclear power plant reactor pressure vessel (RPV)will happen after neu-tron irradiation in service conditions.Relevant researches show that factors of the material properties and work envi-ronment are associated with the irradiation embrittlement.The material properties are the RPV steel properties that associate with the irradiation embrittlement,including the chemical component,microstructure and grain size;and the work environment is the RPV service condition which connects with the embrittlement,containing the neutron fluence,neutron fluence rate,neutron energy spectrum and irradiation temperature.

  17. Reoperations for occluded arterial bypasses in the lower limbs

    Institute of Scientific and Technical Information of China (English)

    2006-01-01

    Background We reviewed the outcomes of reoperations for 29 patients (30 limbs) who had undergone occluded arterial bypass in the lower limbs from May 1996 to September 2005. Methods The 30 lower limbs of the 29 patients with arteriosclerotic obstruction received 44 reoperations, including thrombectomy alone (group T, 27) and inflow or outflow reconstruction plus thrombectomy (group C, 17). Among the 17 operations in group C, 17.6% (3/17) were inflow reconstructions involving the axillary-femoral (1), aorta-iliac (1) and aorta-femoral (1) arteries, and 76.4% (13/17) outflow reconstructions involving the femoral-popliteal bypass-tibial (8), femoral-tibial (1), femoral-popliteal bypass-popliteal arteries below the knee (2), and the femoral-popliteal bypass-tibial-peroneal trunk (2). One patient (1 limb) underwent both inflow and outflow reconstructions with an iliac arterial stent and a graft-popliteal anastomosis patch. Polytetrafluoroethylene (PTFE) grafts were used in the inflow or outflow reconstructions abve the knee. Autovenous grafts or autovenously combined PTFE grafts were used in the outflow reconstructions below the knee. Results The percentages of Fontaine stage III and IV before primary operation and reoperation were 60% (18/30) and 86.7% (26/30), respectively (P0.05). Among 42 reoperations, 19 failed within 1 month in groups T (16) and C (3) (P0.05). The rate of limb salvage was 64.29% (18/28). Conclusions The percentages of Fontaine stage III and IV before reoperation may be much higher than those before primary operation. Thrombectomy plus inflow/outflow reconstruction creates patency better than thrombectomy alone for re-occluded bypass.

  18. Trends in the treatment of coronary disease today. Selective use of PTCA and bypass surgery.

    Science.gov (United States)

    Jones, E L; Craver, J M; Guyton, R A; Bone, D K; Hatcher, C R

    1983-01-01

    Selection and treatment of patients with ischemic heart disease is presently undergoing an evolutionary trend. Percutaneous transluminal coronary angioplasty (PTCA) has been recommended as the initial procedure for many patients with coronary artery disease (CAD), thus possibly redefining candidates for coronary bypass surgery (CABS). Between October 1980 and June 1982, 777 patients having PTCA and 2068 patients having CABS were analyzed for differences in clinical presentation, complications, and early outcome. Patients having CABS were significantly older, had a higher incidence of hypertension (46% vs. 32%), more multivessel disease (80% vs. 12%), and poorer left ventricular function (nl. wall motion = 88% vs. 52%). The incidence of myocardial infarction in patients after PTCA was 1.0% (8/777). Emergency CAB was required in 5.3% of patients following PTCA. There were no deaths following the angioplasty procedure and 25 deaths in 2068 patients having CABS (hospital mortality rate = 1.2%). Since 1973, there has been a progressive decline in hospital mortality rate (now, less than 1%), postoperative infarction (now, 3%), requirement for inotropic drugs (now, 5%) and frequency of IABP (less than 1%). Increasing ability to achieve complete revascularization now means improved survival and freedom from angina with CAB surgery. PTCA and CAB are both procedures that may be used effectively for selected patients, depending on clinical presentation, extent of CAD, and left ventricular function (LVF). Careful patient selection affords the opportunity for use of PTCA in patients with single-vessel disease (SVD) and good LVF and CABS in patients with multivessel disease, regardless of LVF. Symptomatic patients with SVD and total vessel occlusion are not candidates for PTCA. Our data demonstrate that both PTCA and CABS may be accomplished with very low perioperative complications and hospital mortality. PMID:6222708

  19. Cooperative Control of Unmanned Surface Vessels and Unmanned Underwater Vessels for Asset Protection

    Science.gov (United States)

    2015-05-18

    COOPERATIVE LOCALIZATION OF UUVS 9.1 Overview Localization of vehicles beneath the surface presents a very challenging problem given that...A TRIDENT SCHOLAR PROJECT REPORT NO. 444 Cooperative Control of Unmanned Surface Vessels and Unmanned Underwater Vessels for Asset...project report; no. 444 (2015) COOPERATIVE CONTROL OF UNMANNED SURFACE VESSELS AND UNMANNED UNDERWATER VESSELS FOR ASSET PROTECTION by

  20. PV modules without bypass diodes; PV-Module ohne Bypass-Dioden? - Untersuchungen an einer PV-Fassade

    Energy Technology Data Exchange (ETDEWEB)

    Laukamp, H.; Kresse, A.; Leithold, W. [Fraunhofer-Institut fuer Solare Energiesysteme (ISE), Freiburg im Breisgau (Germany)]|[Ingenieurbuero A. Kresse, Karlsruhe (Germany)]|[Solare Systemtechnik GmbH, Freiburg (Germany)

    1998-12-01

    In order to protect solar modules against high output losses with non-homogeneous irradiation, bypass diodes which are mostly accommodated in the module connection socket are used. One would often gladly dispense with these connection sockets for integration of customer-specific large modules in facades. The question: ``Where will the diodes go?`` must then be satisfactorily answered. Both laminating the diodes in the module and their external accommodation cause extra expense elsewhere. It would be ideal if one could dispense with the bypass diodes altogether. This article tries to answer the question, in what conditions this is possible. Starting from the PV facade `Freiburg solar centre`, where one dispensed with the protective diodes, investigations are carried out experimentally and by means of simulation calculations. [Deutsch] Um Solarmodule bei inhomogener Bestrahlung vor hohen Verlustleistungen zu schuetzen, werden ueblicherweise Bypass-Dioden eingesetzt, die zumeist in der Modulanschlussdose untergebracht sind. Zur Fassadenintegration von kundenspezifischen Grossmodulen wuerde man manchmal gerne auf die Anschlussdosen verzichten. Hierfuer muesste zunaechst die Frage `wohin mit den Dioden?` befriedigend beantwortet werden. Sowohl die Einlaminierung der Dioden in das Modul, als auch deren externe Unterbringung versursachen an anderer Stelle einen erhoehten Aufwand. Ideal waere es, wenn man auf die Bypass-Dioden ganz verzichten koennte. Die vorliegende Arbeit versucht die Frage zu beantworten, unter welchen Bedingungen dies moeglich ist. Ausgehend von der PV-Fassade `Solarzentrum Freiburg` - hier wurde auf den Einsatz von Schutzdioden verzichtet - werden experimentell und mittels Simulationsrechnungen Untersuchungen durchgefuehrt. (orig./RHM)

  1. Long-term patency of superficial temporal artery to middle cerebral artery bypass for cerebral atherosclerotic disease: factors determining the bypass patent.

    Science.gov (United States)

    Matano, Fumihiro; Murai, Yasuo; Tateyama, Kojiro; Tamaki, Tomonori; Mizunari, Takayuki; Matsukawa, Hideoshi; Teramoto, Akira; Morita, Akio

    2016-10-01

    Long-term patency of superficial temporal artery to middle cerebral artery (STA-MCA) bypass surgery for atherosclerotic disease and associated risk factors for loss of patency have rarely been discussed. We retrospectively analyzed long-term patency following STA-MCA bypass and evaluated various demographic and clinical factors to identify the ones predictive of postsurgical loss of patency using records of 84 revascularization procedures (58 patients, 45 males; mean age at surgery 63.6 years, range 31-78 years). Bypass patency was diagnosed based on magnetic resonance angiography or three-dimensional computed tomography. The mean follow-up period was 24.7 months (range 6-63 months). Decreased bypass patency was observed in 4 of 58 patients (6.9 %) who collectively underwent 6 bypasses (7.1 %) of 84. All cases of decreased bypass patency were first detected within 6 months of surgery. Bypass patency was not correlated with age, sex, number of anastomoses, postoperative cerebral infarction, or control of postoperative diabetes mellitus. We found a significant association of bypass patency with hyperperfusion (p = 0.01) and postoperative smoking (p = 0.0036). Furthermore, we found a significant association of hyperperfusion with STA diameter (p bypass patency in cerebral atherosclerotic disease patients. Careful monitoring of patency to prevent hyperperfusion and cessation of smoking are recommended, particularly within 6 months of the surgery.

  2. Numerical analysis for the matching of the core driven compression system in a double bypass engine

    Institute of Scientific and Technical Information of China (English)

    ZHANG Xin; LIU Bao-jie

    2011-01-01

    The numerical analysis for the matching of the core driven compression system in a double bypass variable cycle engine was presented in this paper. The system consists of a one-stage-core driven fan stage (CDFS), an inner bypass duet and a five-stage high pressure compressor (HPC), providing two basic operating modes: the single bypass mode and the double bypass mode. Variable vanes are necessary to realize the mode switch of the system. The correct matching in the double bypass mode requires a proper combination of the mass flow, total pressure ratio and blade speed. The work capacity of the system decreases in the double bypass mode and the pressure ratio tends to decrease more for the CDFS and the front stages of the HPC. The overall system efficiency is higher in the double bypass mode. The radial distributions of aerodynamic parameters are similar in different modes. The notable redistribution of mass flow downstream the CDFS in the single bypass mode leads to strong radial flows and additional mixing losses. The absolute flow angles into the inner bypass increase for the inner span and decrease for the outer span when the system is switched from the single bypass mode to the double bypass mode.

  3. Cryopreserved allograft veins as alternative coronary artery bypass conduits: early phase results.

    Science.gov (United States)

    Laub, G W; Muralidharan, S; Clancy, R; Eldredge, W J; Chen, C; Adkins, M S; Fernandez, J; Anderson, W A; McGrath, L B

    1992-11-01

    Traditional autologous conduits are sometimes unavailable or unsuitable to permit total revascularization during coronary artery bypass grafting. In these patients the results of using nonautologous alternative conduits has been disappointing. Encouraged by the excellent long-term results seen with cryopreserved allograft valves, a clinical protocol was developed to evaluate the use of a commercially cryopreserved allograft saphenous vein (CPV). Our protocol consisted of using CPV when left internal mammary arteries and autologous saphenous vein grafts were unavailable or unsuitable for complete revascularization. Blood group (ABO) typed CPVs were thawed and implanted as required using standard surgical techniques. From December 1989 through June 1991, 19 of 1,602 patients who underwent coronary revascularization had CPVs implanted (1.2%). There were no operative deaths. An attempt was made to evaluate the patency of all grafts with coronary arteriography or ultrafast computed tomographic scans. Fourteen patients were available for patency evaluation. Patency rate in the 14 patients studied at a mean of 7 +/- 2 months (range, 2 to 16 months) were: internal mammary artery, 93% (14/15); saphenous vein graft, 80% (4/5); and CPV, 41% (7/17). The patency of the CPV was significantly less than the patency rate for the saphenous vein and internal mammary artery (p = 0.004). We conclude that the short-term patency rate of CPVs is inferior to that of autologous vessels. Due to its poor patency, we recommend that CPV should only be used when no other autologous conduit is available.

  4. In vitro flow investigations in the aortic arch during cardiopulmonary bypass with stereo-PIV.

    Science.gov (United States)

    Büsen, Martin; Kaufmann, Tim A S; Neidlin, Michael; Steinseifer, Ulrich; Sonntag, Simon J

    2015-07-16

    The cardiopulmonary bypass is related to complications like stroke or hypoxia. The cannula jet is suspected to be one reason for these complications, due to the sandblast effect on the vessel wall. Several in silico and in vitro studies investigated the underlying mechanisms, but the applied experimental flow measurement techniques were not able to address the highly three-dimensional flow character with a satisfying resolution. In this work in vitro flow measurements in a cannulated and a non-cannulated aortic silicone model are presented. Stereo particle image velocimetry measurements in multiple planes were carried out. By assembling the data of the different measurement planes, quasi 3D velocity fields with a resolution of~1.5×1.5×2.5 mm(3) were obtained. The resulting velocity fields have been compared regarding magnitude, streamlines and vorticity. The presented method shows to be a suitable in vitro technique to measure and address the three-dimensional aortic CPB cannula flow with a high temporal and spatial resolution.

  5. Arterial pressure and deltoid muscle gas tensions during cardiopulmonary bypass in man.

    Science.gov (United States)

    Stanley, T H

    1978-07-01

    The results of this study demonstrate that standard techniques of conducting cardiopulmonary bypass produce low muscle oxygen and high muscle carbon dioxide tensions and, thus, little perfusion of skeletal muscle. Our findings also show that PmO2 and PmCO2 do not return to pre-bypass levels until the mean arterial blood pressure exceeds 12 kPa (90 torr) during bypass and that utilization of vasopressor drugs during bypass maintains the pressure; but at the expense of muscle blood flow. The data indicate that both high mean blood pressure and high flow are necessary during bypass to ensure skeletal muscle perfusion and suggest, when combined with preliminary animal findings, that this type of bypass perfusion may prove to be superior to standard techniques in hastening recovery after cardio-pulmonary bypass.

  6. Organic fiber/epoxy pressure vessels

    Science.gov (United States)

    Chiao, T. T.; Hamstad, M. A.; Marcon, M. A.

    1974-01-01

    We evaluated the performance of an organic fiber in an epoxy matrix by winding 20-cm diam spherical and cylindrical pressure vessels of various designs. For the spherical vessels, we used soft aluminum liners 0.76 mm thick for a double boss design and 2 mm thick for a single boss design. For the cylindrical vessels, we used both 0.5-mm rubber liners and 0.76-mm soft aluminum liners. Vessels of both types were tested for burst pressure and cyclic fatigue at room temperature and liquid hydrogen temperature. The effects of temperature and vessel shape on the vessel performance factor were negligible. Our vessel fatigue data were marred by premature failure of the liners.

  7. Impact of bypass flow rate and catheter position in veno-venous extracorporeal membrane oxygenation on gas exchange in vivo.

    Science.gov (United States)

    Togo, Konomi; Takewa, Yoshiaki; Katagiri, Nobumasa; Fujii, Yutaka; Kishimoto, Satoru; Date, Kazuma; Miyamoto, Yuji; Tatsumi, Eisuke

    2015-06-01

    The clinical use of veno-venous extracorporeal membrane oxygenation (VVECMO) in adult patients with respiratory failure is rapidly increasing. However, recirculation of blood oxygenated by ECMO back into the circuit may occur in VVECMO, resulting in insufficient oxygenation. The cannula position and bypass flow rate are two major factors influencing recirculation, but the relationship and ideal configuration of these factors are not fully understood. In the present study, we attempted to clarify these parameters for effective gas exchange. VVECMO was performed in eight adult goats under general anesthesia. The position of the drainage cannula was fixed in the inferior vena cava (IVC), but the return cannula position was varied between the IVC, right atrium (RA), and superior vena cava (SVC). At each position, the recirculation rates calculated, and the adequacy of oxygen delivery by ECMO in supplying systemic oxygen demand was assessed by measuring the arterial oxygen saturation (SaO2) and pressure (PaO2). Although the recirculation rates increased as the bypass flow rates increased, SaO2 and PaO2 also increased in any position of return cannula. The recirculation rates and PaO2 were 27 ± 2% and 162 ± 16 mmHg, 36 ± 6% and 139 ± 11 mmHg, and 63 ± 6% and 77 ± 9 mmHg in the SVC, RA and IVC position at 4 L/min respectively. In conclusion, the best return cannula position was the SVC, and a high bypass flow rate was advantageous for effective oxygenation. Both the bypass flow rates and cannula position must be considered to achieve effective oxygenation.

  8. Selection of material for building pressure vessels and chemical plants

    Energy Technology Data Exchange (ETDEWEB)

    Huppertz, P.H.; Retter, A.

    1979-06-01

    The authors give on extensive survey on the materials used in building pressure vessels and chemical plants for a temperature region of -200 to +1000/sup 0/C. The effect of various influences on the material behaviour is critically examined on the existing control plant, where the differences to foreign control are indicated. NE metals also come into consideration apart from steels, especially with low-temperature application.

  9. Totally laparoscopic bypass surgery for aortoiliac occlusive disease in China

    Institute of Scientific and Technical Information of China (English)

    GUO Lian-rui; GU Yong-quan; QI Li-xing; TONG Zhu; WU Xin; GUO Jian-ming; ZHANG Jian

    2013-01-01

    Background Totally laparoscopic aortic surgery is still in its infancy in China.One of the factors preventing adoption of this technique is its steep learning curve.The objective of this study was to evaluate the feasibility and safety of laparoscopic surgery for aortoiliac occlusive disease (AIOD).Methods From November 2008 to November 2012,12 patients were treated for severe AIOD with a totally laparoscopic bypass surgery at our university hospital.The demographic data,operative data,postoperative recovery data,morbidity and mortality were analyzed and compared with those of conventional open approach.Results Twelve totally laparoscopic aortic surgery procedures,including two iliofemoral bypasses (IFB),three unilateral aortofemoral bypasses (UAFB),and seven aortobifemoral bypasses (ABFB),were performed.Conversion to open procedures was required in three patients.The mean operation time was 518 (range,325-840) minutes,mean blood loss was 962 (range,400-2500) ml,and mean aortic anastomosis time was 75 (range,40-150) minutes.Compared with conventional open approach for aortofemoral bypasses performed concomitantly during this period,laparoscopic patients required fewer narcotics and a shorter in-hospital stay and earlier recovery.Postoperative complications developed in four patients,including a single patient with transient left hydronephrosis,ischemic colonic fistula and pneumonia,residual aortic stenosis proximal to the anastomotic site,and asymptomatic partial left renal infarction.All patients recovered and were discharged on postoperative Days 7-14 except one patient that died of respiratory failure on Day 46.All grafts were patent with follow-up imaging performed by Duplex examination,with a mean follow-up time of 10.7 (range,2-61) months.Conclusion Totally laparoscopic bypass surgery is a feasible and safe procedure forAIOD,but attention needs to be paid to improve laparoscopic skills of vascular surgery in order to minimize morbidity during the learning

  10. The Vessel Schedule Recovery Problem

    DEFF Research Database (Denmark)

    Brouer, Berit Dangaard; Plum, Christian Edinger Munk; Vaaben, Bo;

    Maritime transportation is the backbone of world trade and is accountable for around 3% of the worlds CO2 emissions. We present the Vessel Schedule Recovery Problem (VSRP) to evaluate a given disruption scenario and to select a recovery action balancing the trade off between increased bunker cons...... consumption and the impact on the remaining network and the customer service level. The model is applied to 4 real cases from Maersk Line. Solutions are comparable or superior to those chosen by operations managers. Cost savings of up to 58% may be achieved....

  11. A idade influencia os desfechos em pacientes com idade igual ou superior a 70 anos submetidos à cirurgia de revascularização miocárdica isolada Age influences outcomes in 70-year or older patients undergoing isolated coronary artery bypass graft surgery

    Directory of Open Access Journals (Sweden)

    Antônio Sérgio Cordeiro da Rocha

    2012-03-01

    Full Text Available OBJETIVO: Analisar os resultados da cirurgia de revascularização miocárdica (CRVM isolada com circulação extracorpórea em pacientes com idade > 70 anos em comparação àqueles com 70 anos foi fator preditivo independente para maior letalidade operatória (P=0,004 e para RRH (P=0,002, sepse (P=0,002, complicações respiratórias (P 70 anos estão sob maior risco de morte e outras complicações no pós-operatório de CRVM em comparação aos pacientes mais jovens.OBJECTIVE: To analyze the results of isolated on-pump coronary artery bypass graft surgery (CABG in patients >70 years-old in comparison to patients 70 years-old and G2 (age 70-year-old was an independent predictive factor for higher in-hospital mortality (P=0.004, reexploration for bleeding (P=0.002, sepsis (P=0.002, respiratory complications (P 70 years-old were at increased risk of death and other complications in the CABG's postoperative period in comparison to younger patients.

  12. Directional wave measurements using an autonomous vessel

    Science.gov (United States)

    Hole, Lars R.; Fer, Ilker; Peddie, David

    2016-09-01

    An autonomous vessel, the Offshore Sensing Sailbuoy, was used for wave measurements near the Ekofisk oil platform complex in the North Sea (56.5º N, 3.2º E, operated by ConocoPhillips) from 6 to 20 November 2015. Being 100 % wind propelled, the Sailbuoy has two-way communication via the Iridium network and has the capability for missions of 6 months or more. It has previously been deployed in the Arctic, Norwegian Sea and the Gulf of Mexico, but the present study was the first test for wave measurements. During the campaign the Sailbuoy held position about 20 km northeast of Ekofisk (on the lee side) during rough conditions. Mean wind speed measured at Ekofisk during the campaign was 9.8 m/s, with a maximum of 20.4 m/s, with wind mostly from south and southwest. A Datawell MOSE G1000 GPS-based 2 Hz wave sensor was mounted on the Sailbuoy. Mean significant wave height ( H s 1 min) measured was 3 m, whereas maximum H s was 6 m. Mean wave period was 7.7 s, while maximum wave height, H max, was 12.6 m. These measurements have been compared with non-directional Waverider observations at the Ekofisk complex. The agreement between the two data sets was very good, with a mean percent absolute error of 7 % and a linear correlation coefficient of 0.97. The wave frequency spectra measured by the two instruments compared very well, except for low H s (˜1 m), where the motion of the vessel seemed to influence the measurements. Nevertheless, the Sailbuoy performed well during this campaign, and results suggest that it is a suitable platform for wave measurements in a broad range of sea conditions.

  13. Selective Search and Intensity Context Based Retina Vessel Image Segmentation.

    Science.gov (United States)

    Tang, Zhaohui; Zhang, Jin; Gui, Weihua

    2017-03-01

    In the framework of computer-aided diagnosis of eye disease, a new contextual image feature named influence degree of average intensity is proposed for retinal vessel image segmentation. This new feature evaluates the influence degree of current detected pixel decreasing the average intensity of the local row where that pixel located. Firstly, Hessian matrix is introduced to detect candidate regions, for the reason of accelerating segmentation. Then, the influence degree of average intensity of each pixel is extracted. Next, contextual feature vector for each pixel is constructed by concatenating the 8 feature neighbors. Finally, a classifier is built to classify each pixel into vessel or non-vessel based on its contextual feature. The effectiveness of the proposed method is demonstrated through receiver operating characteristic analysis on the benchmarked databases of DRIVE and STARE. Experiment results show that our method is comparable with the state-of-the-art methods. For example, the average accuracy, sensitivity, specificity achieved on the database DRIVE and STARE are 0.9611, 0.8174, 0.9747 and 0.9547, 0.7768, 0.9751, respectively.

  14. Determinants of Vessel Targeting in Vasculitis

    Directory of Open Access Journals (Sweden)

    Gary S. Hoffman

    2004-01-01

    Full Text Available Studies of autoimmune diseases have not yet elucidated why certain organs or vessels become the objects of injury while others are spared. This paper will explore the hypothesis that important differences exist in regions of the aorta that determine vulnerability to diseases, such as atherosclerosis, aortitis, giant cell arteritis and Takayasu's disease. The reader is invited to reassess; (1 whether the aorta is indeed a single homogeneous structure, and (2 whether the initial stage of aortitis (and indeed other diseases considered “autoimmune” may be primarily due to acquired alterations of substrate, that influence unique immune profiles, which by themselves may not be pathogenic. Disease susceptibility and patterns are influenced by many factors that are inborn and acquired. Examples include genetic background, gender, ethnicity, aging, prior and concomitant illnesses, habits, diet, toxin and environmental exposures. Studies of vascular diseases must assess how such variables may affect regional differences in endothelial cells, subendothelial matrix, vascular smooth muscle and the response of each to a variety of stimuli.

  15. Long-term outcome of native artery versus bypass graft intervention in prior coronary artery bypass graft patients with ST-segment elevation myocardial infarction

    Institute of Scientific and Technical Information of China (English)

    LIU Wei; LIU Yu-yang; Venkata K.Mukku; SHI Dong-mei; L(U) Shu-zheng; ZHOU Yu-jie

    2013-01-01

    Background Patients with prior coronary artery bypass graft (CABG) have a poor outcome after acute myocardial infarction (AMI).Little is known about the treatment strategy and outcome of percutaneous coronary intervention (PCI) in these patients.The purpose of this study was to investigate the impact of graft versus native artery PCI on the outcomes of prior CABG patients with AMI.Methods Between September 2005 and October 2011,a total of 140 consecutive patients with previous CABG undergoing PCI for the treatment of AMI were included.Clinical/procedural characteristics and long-term clinical outcomes were compared between graft and native artery PCI patients.Results The mean time interval to prior CABG was (5.6±4.2) years.Thirty patients received graft PCI,success rate being 90%.One hundred and ten patients received native artery PCI,success rate being 90.7% (P >0.05).There were no significant differences in the basic characteristics between the two groups.All patients received drug eluting stents (DESs).Three patients died during hospitalization in the graft-PCI group (10% vs.native PCI 0,P <0.05).After a median followup of two years,major adverse cardiac events (MACE) (myocardial infarction,target vessel revascularization,total death) were 20% with no significant difference between the two groups.Cox regression analysis showed that both diabetes mellitus (DM,HR 3.57,95% CI 1.03-5.75,P <0.05) and primary PCI (HR 5.932,95% Cl 1.91-18.4,P <0.05) were independent predictors of MACE.Conclusions More patients with prior CABG underwent native artery PCI for AMI.PCI to culprit graft vessels had higher in-hospital mortality.DM and primary PCI,but not graft PCI,were predictors for adverse long-term outcome.

  16. Comparison of pressure vessel neutron fluences for the Balakovo-3 reactor with measurements and investigation of the influence of neutron cross sections and number of groups on the results

    Energy Technology Data Exchange (ETDEWEB)

    Barz, H.U.; Boehmer, B.; Konheiser, J.; Stephan, I.

    1998-10-01

    The general methodical questions of experimental and theoretical determination of neutron fluences have been described in connection with the measurements and 3-D Monte Carlo calculation for the Rovno-3 reactor. The same calculation and measurement methods were applied for the Balakovo-3 reactor. In the first part, the results of the comparison for Balakovo will be given and discussed. However, for this reactor the main attention was focussed on investigations of the accuracy of the calculation. In this connection an important question is the influence of neutron data on the results. With this respect not only the source of the data but also the number of energy groups is important. (orig.)

  17. A 7-year, single-center research and long term follow-up of graft patency of robotic total arterial off-pump coronary artery bypass grafting

    Directory of Open Access Journals (Sweden)

    Guo-peng LIU

    2016-06-01

    Full Text Available Objective  The aim of the study was to explore the long-term benefits of coronary artery bypass grafting (CABG. Methods  From January 2007 to November 2014, 240 patients (187 males and 53 females, average age 59 years received robotic off-pump CABG assisted with da Vinci Surgical System (Intuitive Surgical, USA in our center. Totally endoscopic coronary artery bypass (totally robot-assisted TECAB, n=100 or mini-thoracotomy direct coronary artery bypass (free of internal mammary artery, IMA, by robot, MIDCAB, n=140 grafting was performed. Patients were followed-up regularly, and their graft patency was assessed every 6 months by coronary angiography or 64-multi-slide CT angiography. Results  All the procedures were completed successfully without conversion to median sternotomy or cardiopulmonary bypass , there was no operative mortality. 237 unilateral IMA grafts (98.7% and 3 bilateral IMA grafts (1.3% were used. Hybrid revascularization of non-left anterior descending vessels was performed in 24 patients (10%. In the follow-up of 41.1±12.9 months, no death, stroke or myocardial infarction occurred. All grafts were patent before discharge. The IMA graft patency was 97.1% in TECAB and 96.4 % in MIDCAB over 3 years (up to 91 months after surgery. Conclusions  Robotic off-pump CABG using IMA grafts is a safe and effective surgery method in selected patients. The long-term outcome and patency of IMA grafts are excellent. DOI: 10.11855/j.issn.0577-7402.2016.06.15

  18. Systematic comparison of the effectiveness of radial artery and saphenous vein or right internal thoracic artery coronary bypass grafts in non-left anterior descending coronary arteries

    Institute of Scientific and Technical Information of China (English)

    Xiang HU; Qiang ZHAO

    2011-01-01

    Coronary artery bypass grafting surgery is increasingly being carried out on patients with multi-vessel coronary artery disease, but the best grafting candidate for non-left antetior descending coronary arteries is unclear.This research sought to systematically compare the efficacies and safeties of coronary bypass with radial artery and other available grafts. A systematic literature retrieval was performed for all clinical trials comparing the outcomes of coronary artery bypass surgery with radial artery and other grafts in PubMed, EMBASE, and the Cochrane Library.Seven eligible clinical studies, comparing radial artery and great saphenous vein grafts, were found between 1966 and 2010: one prospective non-randomized and six prospective randomized trials. The pooling analysis obtained a relative risk of 0.507 (P<0.05) of graft occlusion in radial arteries compared with great saphenous veins. There was a significantly lower infection rate in arms (i.e., harvest sites for radial arteries) relative to legs (harvest sites for veins), with a pooled relative risk of 0.140 (P<0.05). From the reports on mortality after follow-up ranging from one year to six years,there was no significant difference in mortality between the two graft types (P=0.927). In addition, four cohort controlled trials for radial and right internal thoracic artery grafts were included. The radial graft was associated with less cardiac related events relative to the right intemal thoracic artery graft (P=0.014), but with comparable mortality and comparable rates of repeat percutaneous transluminal coronary angioplasty. Subjects with radial arteries seemed to have a lower occlusion rate and a lower graft harvest site infection rate than those with great saphenous veins. Moreover there were fewer cardiac related events with radial arteries relative to the right internal thoracic artery grafts. More studies are needed to confirm these findings concerning the favorable outcomes of coronary artery

  19. Biomimetic control of vascular smooth muscle cell morphology and phenotype for functional tissue-engineered small-diameter blood vessels.

    Science.gov (United States)

    Chan-Park, Mary B; Shen, Jin Ye; Cao, Ye; Xiong, Yun; Liu, Yunxiao; Rayatpisheh, Shahrzad; Kang, Gavin Chun-Wei; Greisler, Howard P

    2009-03-15

    Small-diameter blood vessel substitutes are urgently needed for patients requiring replacements of their coronary and below-the-knee vessels and for better arteriovenous dialysis shunts. Circulatory diseases, especially those arising from atherosclerosis, are the predominant cause of mortality and morbidity in the developed world. Current therapies include the use of autologous vessels or synthetic materials as vessel replacements. The limited availability of healthy vessels for use as bypass grafts and the failure of purely synthetic materials in small-diameter sites necessitate the development of a biological substitute. Tissue engineering is such an approach and has achieved promising results, but reconstruction of a functional vascular tunica media, with circumferentially oriented contractile smooth muscle cells (SMCs) and extracellular matrix, appropriate mechanical properties, and vasoactivity has yet to be demonstrated. This review focuses on strategies to effect the switch of SMC phenotype from synthetic to contractile, which is regarded as crucial for the engineering of a functional vascular media. The synthetic SMC phenotype is desired initially for cell proliferation and tissue remodeling, but the contractile phenotype is then necessary for sufficient vasoactivity and inhibition of neointima formation. The factors governing the switch to a more contractile phenotype with in vitro culture are reviewed.

  20. Impact of Intraoperative Events on Cerebral Tissue Oximetry in Patients Undergoing Cardiopulmonary Bypass.

    Science.gov (United States)

    Ševerdija, Ervin E; Vranken, Nousjka P A; Teerenstra, Steven; Ganushchak, Yuri M; Weerwind, Patrick W

    2015-03-01

    Previous studies showed that decreased cerebral saturation during cardiac surgery is related to adverse postoperative outcome. Therefore, we investigated the influence of intraoperative events on cerebral tissue saturation in patients undergoing cardiac surgery with cardiopulmonary bypass (CPB). A total of 52 adult patients who underwent cardiac surgery using pulsatile CPB were included in this prospective explorative study. Cerebral tissue oxygen saturation (SctO2) was measured in both the left and right cerebral hemisphere. Intraoperative events, involving interventions performed by anesthesiologist, surgeon, and clinical perfusionist, were documented. Simultaneously, in-line hemodynamic parameters (partial oxygen pressure, partial carbon dioxide pressure, hematocrit, arterial blood pressure, and CPB flow rates) were recorded. Cerebral tissue saturation was affected by anesthetic induction (p retractor (p cardiac surgery. Future studies are needed to identify methods of mitigating periods of reduced cerebral saturation.

  1. Tea May Benefit Blood Vessels

    Institute of Scientific and Technical Information of China (English)

    华剑铭

    2000-01-01

    读到有关饮茶有益健康的消息,我总是充满了自豪感:茶的故乡毕竟在中国。饮茶对人的心脏有益,这已经不是新闻,但是到底如何起到此类保健作用,多年来一直是一个谜。本文揭开了此谜底: Drinking a cup of tea makes blood vessels work better within 2 hours, dilating(扩张)the arteries(动脉)and improving blood flow. 文章令我感动之处在于那些科研人员的敬业精神。比如茶中含有caffeine(咖啡因),饮茶对心脏有利,此“利”是否源于caffeine呢?试验人员为了弄清这 一点,便让另一组受试人员服用等量的caffeine,结果证实:Caffeine had no response on the blood vessel function.】

  2. Jugular-axillary vein bypass for salvage of arteriovenous access.

    Science.gov (United States)

    Fulks, K D; Hyde, G L

    1989-01-01

    Stenosis or occlusion of the subclavian vein can cause incapacitating upper extremity swelling and venous hypertension in the patient with an arteriovenous (AV) access. A case of subclavian vein occlusion is reported that was treated with internal jugular-axillary vein bypass. This procedure resulted in salvage of the access and rapid resolution of the associated upper extremity swelling. It was concluded that jugular-axillary vein bypass should be considered in patients who have massive upper extremity edema resulting from a functioning AV access and ipsilateral subclavian vein occlusion. Patients undergoing creation of an AV access who have had previous temporary subclavian catheters or previous early failure of an AV access should have phlebography before surgery.

  3. Arteriovenous fistulas aggravate the hemodynamic effect of vein bypass stenoses

    DEFF Research Database (Denmark)

    Nielsen, T G; Djurhuus, C; Pedersen, Erik Morre;

    1996-01-01

    PURPOSE: The purpose of this study was to assess the impact of arteriovenous fistulas combined with varying degrees of stenosis on distal bypass hemodynamics and Doppler spectral parameters. METHODS: In an in vitro flow model bypass stenoses causing 30%, 55%, and 70% diameter reduction were induced...... 10 cm upstream of a fistula with low outflow resistance. Flow and intraluminal pressure were measured proximal to the stenosis and downstream of the fistula. The waveform parameters peak systolic velocity, end-diastolic velocity, pulsatility index, and pulse rise time were determined from midstream...... Doppler spectra obtained 10 cm downstream of the fistula. All measurements were carried out with open and clamped fistula. RESULTS: At 30% diameter reducing stenosis opening of the fistula induced a 12% systolic pressure drop across the stenosis but had no adverse effect on the Doppler waveform parameters...

  4. Dobutamine for inotropic support during emergence from cardiopulmonary bypass.

    Science.gov (United States)

    Tinker, J H; Tarhan, S; White, R D; Pluth, J R; Barnhorst, D A

    1976-04-01

    Dobutamine, a recently introduced derivative of dopamine, is reported to retain inotropic properties with less pronounced chronotropic and arrhythmogenic effects than isoproterenol. The drug was evaluated in two doses, 5 mug/kg/min and 10 mug/kg/min, in two groups of ten patients each, during emergence from cardiopulmonary bypass. A third group of five patients was studied similarly with isoproterenol, 0.02 mug/kg/min. Cardiac index increased 16 and 28 per cent eith the two doses of dobutamine, respectively, and 9 per cent with isoproterenol. Heart rate, in contrast, increased 6 and 15 per cent with dobutamine (not significant) and 44 per cent with isoproterenol (significant). Dobutamine seemed to associated with fewer arrhythmias than isoproterenol. It is concluded that dobutamine, 5-10 mug/kg/min, is suitable for use during emergence from cardiopulmonary bypass and may possess advantages over isoproterenol.

  5. Coronary artery bypass grafting in a patient with organophosphate poisoning.

    Science.gov (United States)

    Pieris, Rajeeva R; Fernando, Ravindra

    2015-08-30

    A 43-year-old male, with no previous history of mental illness, was diagnosed with coronary heart disease, after which he became acutely depressed and attempted suicide by ingesting an organophosphate pesticide. He was admitted to an intensive care unit and treated with pralidoxime, atropine, and oxygen. His coronary occlusion pattern required early coronary artery bypass grafting (CABG) surgery. His family, apprehensive of a repeat suicidal attempt, requested surgery be performed as soon as possible. He recovered well from the OP poisoning and was mentally fit to express informed consent 2 weeks after admission. Seventeen days after poisoning, he underwent coronary artery bypass grafting and recovered uneventfully. Six years later, he remains in excellent health. We report this case because to the best of our knowledge there is no literature regarding CABG performed soon after organophosphate poisoning.

  6. ANALYSIS OF 312 CASES OF REPEAT CORONARY ARTERY BYPASS GRAFTING

    Institute of Scientific and Technical Information of China (English)

    陈长志; 陆佩中

    2003-01-01

    Objective To evaluate repeat coronary artery bypass grafting (CABG) in 312 patients.Methods The data of 312 patients (average age 65±9 years) who had CABG operation in Hartford hospital were collected and analyzed. The mean duration follow up after the first CABG was 11.8±4.5 years. A total of 1069 bypass grafts were performed. Among them, 386 were arterial grafts such as internal mammary artery, radial artery and gastroepiploic artery; 682 were venous grafts and 1 Gore-Tex graft. Results The operative mortality was 4. 5%. Fifteen patients (4. 8%) had peri-operative myocardial infarction and 46 patients (15%) had low cardiac output syndrome. Intra-aortic balloon pump (IABP) was used in 131 patients before, during and after operation. One hundred and nineteen patients weaned off IABP and recovered. ConclusionAlthough the difficulties and risk factors were increased, the results of redo CABG were still good.

  7. Numerical Simulation of Bleeding from Ruptured Vessels in Microgravity

    Science.gov (United States)

    Hitt, Darren L.

    2000-11-01

    With the projected increase of manned space activity in the forthcoming years, there will be a heightened risk of serious injury and/or need for surgical procedures resulting in significant blood loss. The bleeding process may be quite different in a microgravity environment compared with the terrestrial setting. Owing to the removal of normally dominant body forces, the mechanism by which the blood exits a ruptured vessel may be greatly influenced by surface tension. Consequently, blood may be ejected from a blood vessel in the form of droplets rather than a continuous leakage; stable domes of blood surrounding a wound may also be possible. The present study represents the first step towards a theoretical and computational model of the bleeding process in microgravity. A finite element-based numerical model (FIDAP 8.5) is developed for the problem of blood loss from a single ruptured vessel into a quiescent, miscible medium. Computations are carried out in two-dimensions and three-dimensions to investigate the rate of blood loss as a function of flow pulsatility, red blood cell concentration, rupture geometry, and vessel wall elasticity. Blood will be modeled as a Newtonian fluid with a concentration-dependent viscosity (Casson's model).

  8. Design of Mooring System for Oil Storage Vessels

    Institute of Scientific and Technical Information of China (English)

    李文龙; 谭家华

    2003-01-01

    The floating oil storage system has been proposed as a new facility for Strategic Petroleum Reserve (SPR) in China. Mooring is one of the key technologies to ensure the safety, reliability, and performance of the oil storage system. This paper describes the concept, analysis, design and reliability of the mooring system. For mooring system design of these oil vessels, analysis is essential of the behavior of the vessel in connection with mooring facilities of nonlinear resilience. A nonlinear mathematical model for analyzing a moored vessel is established and solved. Some results of numerical simulations are presented. Assessment of the safety regarding the mooring system in terms of failure probability is carried out. Another simulation model for calculating the failure probability of the mooring system is proposed. The design parameters that have an influence on the characteristics of the failure probability have been identified. The simulation results show that the mooring system has an annual reliability value of 0.999998. The proposed simulation method is proved to be effective in quantitative evaluation of the safety of the mooring system for floating oil storage vessels.

  9. The impact of avoiding cardiopulmonary by-pass during coronary artery bypass surgery in elderly patients: the Danish On-pump Off-pump Randomisation Study (DOORS)

    DEFF Research Database (Denmark)

    Houlind, Kim; Kjeldsen, Bo Juul; Madsen, Susanne Nørgaard;

    2009-01-01

    BACKGROUND: Coronary Artery Bypass Graft operation for ischemic heart disease provides improved quality of life and, in some patients, prolonged survival. Concern has, however, been raised about complications that may be related to the use of cardiopulmonary by-pass (CPB) and aortic cross-clampin...

  10. secondary Prevention of Coronary Events by Coronary Artery Bypass Surgery

    OpenAIRE

    2003-01-01

    Coronary artery bypass surgery has shown its superiority on other therapeutic options in specific but frequent indications such as left main lesions, multivessel disease with alteration of ventricular function, proximal lesions of the LAD, and multivessel diseases in diabetic patients. After reviewing the epidemiology of coronary artherosclerosis, we emphasize the efficacy of the surgical treatment compared to medical or interventional therapy for preventing ischemic events. The results deriv...

  11. Human gut microbiota in obesity and after gastric bypass.

    Science.gov (United States)

    Zhang, Husen; DiBaise, John K; Zuccolo, Andrea; Kudrna, Dave; Braidotti, Michele; Yu, Yeisoo; Parameswaran, Prathap; Crowell, Michael D; Wing, Rod; Rittmann, Bruce E; Krajmalnik-Brown, Rosa

    2009-02-17

    Recent evidence suggests that the microbial community in the human intestine may play an important role in the pathogenesis of obesity. We examined 184,094 sequences of microbial 16S rRNA genes from PCR amplicons by using the 454 pyrosequencing technology to compare the microbial community structures of 9 individuals, 3 in each of the categories of normal weight, morbidly obese, and post-gastric-bypass surgery. Phylogenetic analysis demonstrated that although the Bacteria in the human intestinal community were highly diverse, they fell mainly into 6 bacterial divisions that had distinct differences in the 3 study groups. Specifically, Firmicutes were dominant in normal-weight and obese individuals but significantly decreased in post-gastric-bypass individuals, who had a proportional increase of Gammaproteobacteria. Numbers of the H(2)-producing Prevotellaceae were highly enriched in the obese individuals. Unlike the highly diverse Bacteria, the Archaea comprised mainly members of the order Methanobacteriales, which are H(2)-oxidizing methanogens. Using real-time PCR, we detected significantly higher numbers of H(2)-utilizing methanogenic Archaea in obese individuals than in normal-weight or post-gastric-bypass individuals. The coexistence of H(2)-producing bacteria with relatively high numbers of H(2)-utilizing methanogenic Archaea in the gastrointestinal tract of obese individuals leads to the hypothesis that interspecies H(2) transfer between bacterial and archaeal species is an important mechanism for increasing energy uptake by the human large intestine in obese persons. The large bacterial population shift seen in the post-gastric-bypass individuals may reflect the double impact of the gut alteration caused by the surgical procedure and the consequent changes in food ingestion and digestion.

  12. Assessing Patient bypass Behavior Using Taxi Trip Origin–Destination (OD Data

    Directory of Open Access Journals (Sweden)

    Gege Yang

    2016-09-01

    Full Text Available Many patients prefer to use the best hospitals even if there are one or more other hospitals closer to their homes; this behavior is called “hospital bypass behavior”. Because this behavior can be problematic in urban areas, it is important that it be reduced. In this paper, the taxi GPS data of Beijing and Suzhou were used to measure hospital bypass behavior. The “bypass behavior index” (BBI represents the bypass behavior for each hospital. The results indicated that the mean hospital bypass trip distance value ranges from 5.988 km to 9.754 km in Beijing and from 4.168 km to 10.283 km in Suzhou. In general, the bypass shares of both areas show a gradually increasing trend. The following hospitals exhibited significant patient bypass behavior: the 301 Hospital, Beijing Children’s Hospital, the Second Affiliated Hospital of Soochow University and the Suzhou Hospital of Traditional Chinese Medicine. The hospitals’ reputation, transport accessibility and spatial distribution were found to be the main factors affecting patient bypass behavior. Although the hospital bypass phenomena generally appeared to be more pronounced in Beijing, the bypass trip distances between hospitals were found to be more significant in Suzhou.

  13. Distal wound complications following pedal bypass: analysis of risk factors.

    Science.gov (United States)

    Robison, J G; Ross, J P; Brothers, T E; Elliott, B M

    1995-01-01

    Wound complications of the pedal incision continue to compromise successful limb salvage following aggressive revascularization. Significant distal wound disruption occurred in 14 of 142 (9.8%) patients undergoing pedal bypass with autogenous vein for limb salvage between 1986 and 1993. One hundred forty-two pedal bypass procedures were performed for rest pain in 66 patients and tissue necrosis in 76. Among the 86 men and 56 women, 76% were diabetic and 73% were black. All but eight patients had a history of diabetes and/or tobacco use. Eight wounds were successfully managed with maintenance of patent grafts from 5 to 57 months. Exposure of a patent graft precipitated amputation in three patients, as did graft occlusion in an additional patient. One graft was salvaged by revision to the peroneal artery and one was covered by a local bipedicled flap. Multiple regression analysis identified three factors associated with wound complications at the pedal incision site: diabetes mellitus (p = 0.03), age > 70 years (p = 0.03), and rest pain (p = 0.05). Ancillary techniques ("pie-crusting") to reduce skin tension resulted in no distal wound problems among 15 patients considered to be at greatest risk for wound breakdown. Attention to technique of distal graft tunneling, a wound closure that reduces tension, and control of swelling by avoiding dependency on and use of gentle elastic compression assume crucial importance in minimizing pedal wound complications following pedal bypass.

  14. Percutaneous mechanical thrombectomy for treatment of acute femoropopliteal bypass occlusion

    Directory of Open Access Journals (Sweden)

    Lichtenberg M

    2012-05-01

    Full Text Available Michael Lichtenberg1, Matthias Käunicke1, Birgit Hailer1,21Cardiovascular Clinic, Vascular Center, Katholisches Klinikum Essen, Germany; 2University of Witten/Herdecke, GermanyAbstract: Acute and subacute ischemia of the legs in acute and subacute femoropopliteal bypass occlusion is a dramatic situation that endangers the survival of the limbs, depending on the severity of the ischemia. Different therapy options like percutaneous mechanical thrombectomy procedures, which include rotational thrombectomy, have become available in recent years, in addition to local lysis and surgical thrombectomy. Surgical thrombectomy using the Fogarty catheter technique, in particular, shows an increased incidence of perioperative complications but only small technical success rates in randomized trials. On the other hand, local lysis is associated with increased costs due to resource-consuming measures, such as intensive monitoring and repeat angiographies, in addition to bleeding complications. In the past, further development of the Straub Rotarex® system as an endovascular therapy option has demonstrated good success leading to amputation-free survival in multiple studies. At the same time, a low rate of complications with use has been documented. Most examinations have been conducted in the thigh. To date, there are little investigational data on its use in acutely and subacutely occluded femoropopliteal bypasses. In this paper, the current study-based significance of the Rotarex system for this indication is analyzed based on the existing literature and the authors' own experiences with 22 patients.Keywords: acute limb ischemia, femoropopliteal bypass, local lysis, rotational thrombectomy

  15. Pipelining and bypassing in a RISC/DSP processor

    Science.gov (United States)

    Yu, Guojun; Yao, Qingdong; Liu, Peng; Jiang, Zhidi; Li, Fuping

    2005-03-01

    This paper proposes pipelining and bypassing unit (BPU) design method in our 32-bit RISC/DSP processor: MediaDsp3201 (briefly, MD32). MD32 is realized in 0.18μm technology, 1.8v, 200MHz working clock and can achieve 200 million/s Multiply-Accumulate (MAC) operations. It merges RISC architecture and DSP computation capability thoroughly, achieves fundamental RISC, extended DSP and single instruction multiple data (SIMD) instruction set with various addressing modes in a unified and customized DSP pipeline stage architecture. We will first describe the pipeline structure of MD32, comparing it to typical RISC-style pipeline structure. And then we will study the validity of two bypassing schemes in terms of their effectiveness in resolving pipeline data hazards: Centralized and Distributed BPU design strategy (CBPU and DBPU). A bypassing circuit chain model is given for DBPU, which register read is only placed at ID pipe stage. Considering the processor"s working clock which is decided by the pipeline time delay, the optimization of circuit that serial select with priority is also analyzed in detail since the BPU consists of a long serial path for combination logic. Finally, the performance improvement is analyzed.

  16. Ileal loop interposition:an alternative biliar y bypass technique

    Institute of Scientific and Technical Information of China (English)

    Felipe JF Coimbra; Alessandro L Diniz; Heber SC Ribeiro; Wilson L Costa Jr.; Eduardo NP Lima; André L Montagnini

    2010-01-01

    BACKGROUND: Obstructive jaundice is a common condition in advanced digestive cancer. Palliative procedures can improve quality of life and allow patients to attempt a systemic treatment. Bilioenteric anastomosis is still the procedure of choice for patients in many centers. When a surgical bypass is not possible, biliary drainage can be done by placing endoscopic or transparietal stents, which are less durable methods even when an expandable stent is employed. METHODS: A 47-year-old male with an excellent clinical status and a previous cholecystectomy and an exploratory laparotomy for advanced gastric cancer was referred with obstructive jaundice. A preoperative CT scan showed a dilated bile duct and a small mass at the distal hepatic hilum. No other signs of metastasis were found. A surgical bilioenteric anastomosis was indicated. At surgery, a distal choledochal obstruction and a mesenteric retraction by a lymph node mass prevented the jejunum to ascend for a bilioenteric anastomosis. Surgically, an alternative bilioenteric bypass was performed by means of an ileal loop interposition between the bile duct and the jejunum. RESULT: The recovery of the patient was uneventful and his bilirubin levels normalized after one week. The patient was then referred for systemic chemotherapy. CONCLUSIONS: This alternative biliary bypass can be safely and easily performed, and may be a good alternative for patients already referred for surgery because of a better life expectancy and when the jejunum is not an alternative.

  17. Breast cancer biomarkers predict weight loss after gastric bypass surgery

    Directory of Open Access Journals (Sweden)

    Sauter Edward R

    2012-01-01

    Full Text Available Abstract Background Obesity has long been associated with postmenopausal breast cancer risk and more recently with premenopausal breast cancer risk. We previously observed that nipple aspirate fluid (n levels of prostate specific antigen (PSA were associated with obesity. Serum (s levels of adiponectin are lower in women with higher body mass index (BMI and with breast cancer. We conducted a prospective study of obese women who underwent gastric bypass surgery to determine: 1 change in n- and s-adiponectin and nPSA after surgery and 2 if biomarker change is related to change in BMI. Samples (30-s, 28-n and BMI were obtained from women 0, 3, 6 and 12 months after surgery. Findings There was a significant increase after surgery in pre- but not postmenopausal women at all time points in s-adiponectin and at 3 and 6 months in n-adiponectin. Low n-PSA and high s-adiponectin values were highly correlated with decrease in BMI from baseline. Conclusions Adiponectin increases locally in the breast and systemically in premenopausal women after gastric bypass. s-adiponectin in pre- and nPSA in postmenopausal women correlated with greater weight loss. This study provides preliminary evidence for biologic markers to predict weight loss after gastric bypass surgery.

  18. EARLY POSTOPERATIVE COMPLICATIONS IN ROUX-EN-Y GASTRIC BYPASS

    Science.gov (United States)

    STOLL, Aluisio; ROSIN, Leandro; DIAS, Mariana Fernandes; MARQUIOTTI, Bruna; GUGELMIN, Giovana; STOLL, Gabriela Fanezzi

    2016-01-01

    ABSTRACT Background: Roux-en-Y gastric bypass is one of the most common bariatric surgery and leads to considerable weight loss in the first months. Aim: To quantify the main early postoperative complications in patients submitted to the gastric bypass. Method: Observational retrospective cohort. Data of 1051 patients with class II obesity associated with comorbidities or class III obesity submitted to the gastric bypass with 30 days of follow-up starting from the date of the surgery. Results: The age average was 36 years with a predominance of females (81.1%). The mean preoperative body mass index was 43 kg/m². The major complication was fistula (2.3%), followed by intestinal obstruction (0.5%) and pulmonary embolism (0.5%). Death occurred in 0.6% of the cases. Conclusion: In the period of 30 days after surgery the overall complication rate was 3.8%; reoperation was necessary in 2.6% and death occurred in 0.6%. Fistula was the main complication and the leading cause of hospitalization in intensive care unit, reoperation and death. PMID:27683781

  19. COMPLICATIONS RELATED TO GASTRIC BYPASS PERFORMED WITH DIFFERENT GASTROJEJUNAL DIAMETERS

    Science.gov (United States)

    SAMPAIO-NETO, José; BRANCO-FILHO, Alcides José; NASSIF, Luis Sérgio; BROSKA, Anne Caroline; KAMEI, Douglas Jun; NASSIF, André Thá

    2016-01-01

    ABSTRACT Background: Among the options for surgical treatment of obesity, the most widely used has been the Roux-en-Y gastric bypass. The gastrojejunal anastomosis can be accomplished in two ways: handsewn or using circular and linear stapled. The complications can be divided in early and late. Aim: To compare the incidence of early complications related with the handsewn gastrojejunal anastomosis in gastric bypass using Fouchet catheter with different diameters. Method: The records of 732 consecutive patients who had undergone the bypass were retrospectively analyzed and divided in two groups, group 1 with 12 mm anastomosis (n=374), and group 2 with 15 mm (n=358). Results: The groups showed anastomotic stenosis with rates of 11% and 3.1% respectively, with p=0.05. Other variables related to the anastomosis were also analyzed, but without statistical significance (p>0.05). Conclusion: The diameter of the anastomosis of 15 mm was related with lower incidence of stenosis. It was found that these patients had major bleeding postoperatively and lower surgical site infection, and in none was observed presence of anastomotic leak. PMID:27683767

  20. Hydrogen storage in insulated pressure vessels

    Energy Technology Data Exchange (ETDEWEB)

    Aceves, S.M.; Garcia-Villazana, O. [Lawrence Livermore National Lab., CA (United States)

    1998-08-01

    Insulated pressure vessels are cryogenic-capable pressure vessels that can be fueled with liquid hydrogen (LH{sub 2}) or ambient-temperature compressed hydrogen (CH{sub 2}). Insulated pressure vessels offer the advantages of liquid hydrogen tanks (low weight and volume), with reduced disadvantages (lower energy requirement for hydrogen liquefaction and reduced evaporative losses). This paper shows an evaluation of the applicability of the insulated pressure vessels for light-duty vehicles. The paper shows an evaluation of evaporative losses and insulation requirements and a description of the current analysis and experimental plans for testing insulated pressure vessels. The results show significant advantages to the use of insulated pressure vessels for light-duty vehicles.

  1. Automatic Vessel Segmentation on Retinal Images

    Institute of Scientific and Technical Information of China (English)

    Chun-Yuan Yu; Chia-Jen Chang; Yen-Ju Yao; Shyr-Shen Yu

    2014-01-01

    Several features of retinal vessels can be used to monitor the progression of diseases. Changes in vascular structures, for example, vessel caliber, branching angle, and tortuosity, are portents of many diseases such as diabetic retinopathy and arterial hyper-tension. This paper proposes an automatic retinal vessel segmentation method based on morphological closing and multi-scale line detection. First, an illumination correction is performed on the green band retinal image. Next, the morphological closing and subtraction processing are applied to obtain the crude retinal vessel image. Then, the multi-scale line detection is used to fine the vessel image. Finally, the binary vasculature is extracted by the Otsu algorithm. In this paper, for improving the drawbacks of multi-scale line detection, only the line detectors at 4 scales are used. The experimental results show that the accuracy is 0.939 for DRIVE (digital retinal images for vessel extraction) retinal database, which is much better than other methods.

  2. Multiscale Vessel-guided Airway Tree Segmentation

    DEFF Research Database (Denmark)

    Lo, Pechin Chien Pau; Sporring, Jon; de Bruijne, Marleen

    2009-01-01

    that is trained to differentiate between airway and non-airway voxels. Vessel and airway orientation information are used in the form of a vessel orientation similarity measure, which indicates how similar the orientation of the an airway candidate is to the orientation of the neighboring vessel. The method...... is evaluated within EXACT’09 on a diverse set of CT scans. Results show a favorable combination of a relatively large portion of the tree detected correctly with very few false positives....

  3. Exponential Stabilization of an Underactuated Surface Vessel

    Directory of Open Access Journals (Sweden)

    Kristin Y. Pettersen

    1997-07-01

    Full Text Available The paper shows that a large class of underactuated vehicles cannot be asymptotically stabilized by either continuous or discontinuous state feedback. Furthermore, stabilization of an underactuated surface vessel is considered. Controllability properties of the surface vessels is presented, and a continuous periodic time-varying feedback law is proposed. It is shown that this feedback law exponentially stabilizes the surface vessel to the origin, and this is illustrated by simulations.

  4. SUrgical versus PERcutaneous Bypass: SUPERB-trial; Heparin-bonded endoluminal versus surgical femoro-popliteal bypass: study protocol for a randomized controlled trial

    Directory of Open Access Journals (Sweden)

    Wallis de Vries Bas M

    2011-07-01

    Full Text Available Abstract Background Endovascular treatment options for the superficial femoral artery are evolving rapidly. For long lesions, the venous femoropopliteal bypass considered to be superior above the prosthetic bypass. An endoluminal bypass, however, may provide equal patency rates compared to the prosthetic above knee bypass. The introduction of heparin-bonded endografts may further improve patency rates. The SUrgical versus PERcutaneous Bypass (SuperB study is designed to assess whether a heparin-bonded endoluminal bypass provides equal patency rates compared to the venous bypass and to prove that it is associated with improved quality of life, related to a decreased complication rate, or not. Methods/design Two-hundred-twenty-two patients with peripheral arterial occlusive disease, category 3-6 according to Rutherford, will be randomized in two treatment arms; 1. the surgical femoro-popliteal bypass, venous whenever possible, and 2. the heparin-bonded endoluminal bypass. The power analysis was based on a non-inferiority principle, with an effect size of 90% and 10% margins (alpha 5%, power 80%. Patients will be recruited from 5 teaching hospitals in the Netherlands during a 2-year period. The primary endpoint is primary patency and quality of life evaluated by the RAND-36 questionnaire and the Walking Impairment Questionnaire. Secondary endpoints include secondary patency, freedom-from-TLR and complications. Discussion The SuperB trial is a multicentre randomized controlled trial designed to show non-inferiority in patency rates of the heparin-bonded endograft compared to the surgical bypass for treatment of long SFA lesions, and to prove a better quality of life using the heparin bonded-endograft compared to surgically treatment, related to a reduction in complications. Trial Registration Clinicaltrials: NCT01220245

  5. Coronary artery bypass grafting versus percutaneous intervention in coronary revascularization: a historical perspective and review

    Directory of Open Access Journals (Sweden)

    Burgess SN

    2015-06-01

    Full Text Available Sonya N Burgess,1 John J Edmond,2 Craig P Juergens,1 John K French11Department of Cardiology, Liverpool Hospital and South Western Sydney Clinical School, The University of New South Wales, Sydney, NSW, Australia; 2Department of Cardiology, Dunedin Public Hospital, Dunedin, New Zealand Background: Coronary artery bypass graft surgery is arguably the most intensively studied surgical procedure, and percutaneous coronary intervention (PCI has been subjected to more randomized clinical trials than any other interventional procedure. Changes seen in revascularization techniques have been numerous. The rapid evolution of evidence-based revascularization procedures has occurred as a result of many pivotal large randomized clinical trials. Objective: This review compares and contrasts outcomes from two coronary revascularization techniques, coronary artery bypass grafting (CABG and PCI, with particular reference to the landmark trials that inform practice guidelines. Methods: We undertook a comprehensive review of published literature addressing trials in this field performed to address current knowledge both in the predrug-eluting stent and postdrug-eluting stent era. Results and discussion: Surgical and percutaneous revascularization strategies have different strengths and weaknesses, and neither strategy is superior in all patients, clinical presentations, or anatomical subgroups. Current data support the use of percutaneous intervention in ST elevation myocardial infarction and in single-vessel disease. In noncomplex multivessel disease and isolated left main stem PCI, the data support non-inferiority of PCI compared to CABG as reflected in the 2014 European Society of Cardiology guidelines. Landmark revascularization trials of multivessel disease comparing CABG to PCI found no survival benefit to CABG over PCI, except in patients with complex disease. In these trials, revascularization drove differences in primary endpoints and in all but the

  6. Laparoscopic gastric bypass to robotic gastric bypass: time and cost commitment involved in training and transitioning an academic surgical practice.

    Science.gov (United States)

    Lyn-Sue, Jerome R; Winder, Josh S; Kotch, Shannon; Colello, Jacob; Docimo, Salvatore

    2016-06-01

    The Roux-en-Y gastric bypass is the gold standard procedure for weight loss. This relatively complex procedure has excellent outcomes when performed via laparoscopy. The advent of the DaVinci robotic platform has been a technological advancement. Our goal is to provide information regarding the cost, time commitment, and advantages of transitioning an LRYGB program to an RRYGB program in an academic setting. We retrospectively reviewed the last 25 laparoscopic gastric bypass procedures and the first 25 robotic gastric bypass procedures performed by a single surgeon. We compared clinical outcomes and focused on time and hospital cost during this transition phase. There was no significant demographic difference between the groups. The mean age was 41.7 (RRYGB) years vs 43.4 (LRYGM) years. The mean BMI were similar between groups, 45.3 vs 46.5 kg/m(2) for RRYGB and LRYGB. No anastomotic leaks or mortalities were noted. There was one anastomotic stricture in both groups. Excess weight loss was similar in both groups at 1 year. There was a significant increase in operative time with RRYGB, mean 241 min vs mean 174 min (p = 0.0005). Operative time fell by 25 min after the first 10 cases. The hospital cost was also increased with RRYGB mean $5922 vs $4395 (p = 0.03). Transitioning from a laparoscopic to a robotic practice can be done safely, however, the initial operative times were longer and the hospital cost was higher for robotic gastric bypass. We hope in the future that these will decrease after overcoming the learning and as the technology becomes widespread.

  7. [Results of using composite bypass grafts with infragenicular distal anastomosis].

    Science.gov (United States)

    Pokrovskiĭ, A V; Iakhontov, D I

    2014-01-01

    The authors share herein their experience with composite bypass grafts and PTFE synthetic prostheses used for treatment of obliterating diseases of the infrainguinal-segment arteries. The data of the study were based on the outcomes obtained in 92 patients. The authors assessed the condition of the outflow pathways and their effect on patency of composite bypass grafts in the immediate and remote postoperative periods, followed by comparative analysis of the short- and long-term therapeutic outcomes after using composite bypass grafts and PTFE synthetic prostheses in the infragenicular position for femoropopliteal and femorotibial reconstructions, also assessing the effect of the localization of the distal anastomosis on the immediate and remote therapeutic outcomes. Based on the obtained findings it was determined that the immediate results of patency depended upon the state of the outflow pathways and localization of the distal anastomosis. Thus, by the 1st, 3rd and 5th year of follow up patency of transplants in patients with the runoff score less than 7.0 amounted to 78.3, 21.7 and 4.3%, respectively. Analogous indices of patency in patients with the runoff score equalling or greater than 7.0 amounted to 60.7 and 3.6% for the 1st and 3rd year, respectively. The remote results of patency turned out to depend on the type of a vascular transplant and the state of the outflow pathways and did not depend on the localization of the distal anastomosis. Thus, the remote results of patency for the composite bypass graft for the 1st, 3rd and 5th year of follow up amounted to 74.5, 19.6 and 5.9%, respectively, versus 60.8 and 8.6% by the first and third year for the PTFE prosthesis. The limb salvage rate at the same terms for the composite bypass graft amounted to 94.1, 84.3 and 78.4% versus 73.9, 56.5 and 52.2% for the PTFE prosthesis.

  8. Role of precoating in artificial vessel endothelialization

    Institute of Scientific and Technical Information of China (English)

    肖乐; 时德

    2004-01-01

    @@ As the progress of vascular surgery, artificial vessels have become the substitute for large and middle diameter vessels but have not for small diameter ones owing to thrombogenesis and occlusion within a short period of time after being applied.Artificial vessel endothelialization is one of the ideal methods to resolve such issue and has been improved continuously since Herring1 in 1978 put forward this term in the first time and utilized vascular endothelial cells (ECs) harvested from living animals to perform the test of artificial vessel endothelialization.

  9. Passage of downstream migrant American eels through an airlift-assisted deep bypass

    Science.gov (United States)

    Haro, Alexander J.; Watten, Barnaby J.; Noreika, John

    2016-01-01

    Traditional downstream guidance and bypass facilities for anadromous fishes (i.e., surface bypasses, surface guidance structures, and behavioral barriers) have frequently been ineffective for anguillid eels. Because eels typically spend the majority of their time near the bottom in the vicinity of intake structures, deep bypass structures with entrances near the bottom hold promise for increased effectiveness, thereby aiding in the recovery of this important species. A new design of a deep bypass system that uses airlift technology (the Conte Airlift Bypass) to induce flow in a bypass pipe was tested in a simulated intake entrance environment under controlled laboratory conditions. Water velocities of 0.9–1.5 m s−1 could be generated at the bypass entrance (opening with 0.073 m2 area), with corresponding flows through the bypass pipe of 0.07–0.11 m3 s−1. Gas saturation and hydrostatic pressure within the bypass pipe did not vary appreciably from a control (no air) condition under tested airflows. Migratory silver-phase American eels (Anguilla rostrata) tested during dark conditions readily located, entered, and passed through the bypass; initial avoidance rates (eels approaching but not entering the bypass entrance) were lower at higher entrance velocities. Eels that investigated the bypass pipe entrance tended to enter headfirst, but those that then exited the pipe upstream did so more frequently at lower entrance velocities. Eels appeared to swim against the flow while being transported downstream through the pipe; median transit times through the bypass for each test velocity ranged from 5.8 to 12.2 s, with transit time decreasing with increasing entrance velocity. Eels did not show strong avoidance of the vertical section of the pipe which contained injected air. No mortality or injury of bypassed eels was observed, and individual eels repeatedly passed through the bypass at rates of up to 40 passes per hour, suggesting that individuals do not

  10. Anatomic study of infrapopliteal vessels.

    Science.gov (United States)

    Lappas, D; Stavropoulos, N A; Noussios, G; Sakellariou, V; Skandalakis, P

    2012-08-01

    The purpose of this project is to study and analyse the anatomical variations of the infrapopliteal vessels concerning their branching pattern. A reliable sample of one hundred formalin-fixed adult cadavers was dissected by the Anatomical Laboratory of Athens University. The variations can be classified in the following way: the normal branching of the popliteal artery was present in 90%. The remainder revealed variant branching patterns: hypoplastic or aplastic posterior tibial artery and the pedis arteries arising from the peroneal (3%); hypoplastic or aplastic anterior tibial artery (1.5%); and the dorsalis pedis formed by two equal branches, arising from the peroneal and the anterior tibial artery (2%). The variations were more frequent in females and in short-height individuals. Knowledge of these variations is rather important for any invasive technic concerning lower extremities.

  11. Prevention and treatment of infection after lower extremity arterial bypass%下肢动脉旁路术后人工血管感染的预防

    Institute of Scientific and Technical Information of China (English)

    胡松杰; 陆彬; 郎德海

    2014-01-01

    目的:探讨下肢动脉旁路术后人工血管感染的处理方法,为预防和治疗患者感染提供参考依据。方法选取2004年5月-2013年5月在医院接受治疗的下肢动脉旁路术后人工血管感染患者9例;对所有患者进行病原菌培养及药敏试验,根据结果选择抗菌药物,出院后对患者进行定期随访,记录随访结果。结果9例感染患者术后保肢6例、截肢2例、围手术期死亡1例,死亡原因为并发心肌梗死;8例术后生存患者均进行12~60个月随访,其中1例患者在随访中死亡,死亡原因为脑出血;生存7例,其中3例保留通畅血管,2例去除人工血管未重建血运,2例截肢患者无异常;下肢动脉旁路术后人工血管感染病死率为22.22%、存活率为77.78%、截肢率为22.22%。结论下肢动脉旁路术后人工血管感染病死率和截肢率较高,临床上一旦发生,大多需要取出人工血管,对于血运通畅者可考虑保留人工血管。%OBJECTIVE To investigate the treatment methods for infection after lower extremity arterial bypass ,so as to provide reference for better prevention and treatment of patient infection .METHODS Totally 9 patients who had artificial blood vessel infection after lower extremity arterial bypass during May 2004 to May 2013 in the hos‐pital were enrolled .Pathogen culture and antimicrobial susceptibility test were conducted for all the patients and the appropriate antimicrobial drugs were selected according to the test results .Regular follow‐ups were conducted after discharge ,and the follow‐up results were recorded .RESULTS Among the nine patients ,there were six cases of limb salvage ,two cases of amputation ,one case of perioperative death due to concurrence of myocardial infarc‐tion .The eight cases of survival patients were followed up for 12~60 months and one patient died during follow‐up due to cerebral hemorrhage .The other seven

  12. Operation characteristics of AMS-02 loop heat pipe with bypass valve

    CERN Document Server

    Wang, N H; Xin, G M; Song, J W; Cui, Z; Burger, J; Du, W J; Luo, F; Cheng, L

    2011-01-01

    Loop heat pipes (LHPs) were designed for the alpha magnetic spectrometer (AMS-02) to dissipate heat from the cryocoolers. A bypass valve is applied to the LHP to keep the cryocooler temperature above its limit (-20A degrees C) in cold environment. Extensive experiments were performed on operation characteristics of LHPs with the bypass valve for AMS-02 during thermal vacuum and thermal balance (TVTB) test. We found that the bypass valve can start up successfully in cold environment. With the bypass valve, the evaporator temperature is stable and can meet the requirement of the cryocooler. We analyzed three operating modes of the bypass valve. Set point temperature and regulation temperature shifts were observed and their relations with the bypass valve temperature were given.

  13. 46 CFR 42.05-63 - Ship(s) and vessel(s).

    Science.gov (United States)

    2010-10-01

    ...) and vessel(s) are interchangeable or synonymous words, and include every description of watercraft, other than a seaplane on the water, used or capable of being used as a means of transportation on water....

  14. Estimation of ex-vessel steam explosion pressure loads

    Energy Technology Data Exchange (ETDEWEB)

    Leskovar, Matjaz [Jozef Stefan Institute, Jamova cesta 39, SI-1000 Ljubljana (Slovenia)], E-mail: matjaz.leskovar@ijs.si; Ursic, Mitja [Jozef Stefan Institute, Jamova cesta 39, SI-1000 Ljubljana (Slovenia)

    2009-11-15

    An ex-vessel steam explosion may occur when, during a severe reactor accident, the reactor vessel fails and the molten core pours into the water in the reactor cavity. A steam explosion is a fuel coolant interaction process where the heat transfer from the melt to water is so intense and rapid that the timescale for heat transfer is shorter than the timescale for pressure relief. This can lead to the formation of shock waves and production of missiles that may endanger surrounding structures. A strong enough steam explosion in a nuclear power plant could jeopardize the containment integrity and so lead to a direct release of radioactive material to the environment. In this article, different scenarios of ex-vessel steam explosions in a typical pressurized water reactor cavity are analyzed with the code MC3D, which is being developed for the simulation of fuel-coolant interactions. A parametric study was performed varying the location of the melt release (central, right and left side melt pour), the cavity water subcooling, the primary system overpressure at vessel failure and the triggering time for explosion calculations. The main purpose of the study was to establish the influence of the varied parameters on the fuel-coolant interaction behaviour, to determine the most challenging cases and to estimate the expected pressure loadings on the cavity walls. For the most explosive central, right side and left side melt pour scenarios a detailed analysis of the explosion simulation results was performed. The study shows that for some ex-vessel steam explosion scenarios higher pressure loads are predicted than obtained in the OECD programme SERENA phase 1.

  15. Novel blood sampling method of an artificial endocrine pancreas via the cardiopulmonary bypass circuit.

    Science.gov (United States)

    Kawahito, Shinji; Higuchi, Seiichi; Mita, Naoji; Kitagawa, Tetsuya; Kitahata, Hiroshi

    2013-12-01

    We tried to perform continuous blood glucose monitoring during cardiovascular surgery involving cardiopulmonary bypass using an artificial endocrine pancreas (STG-22 or -55; Nikkiso, Tokyo, Japan); however, we often encountered problems during these procedures because insufficient blood was obtained for monitoring. Thus, we started performing the blood sampling via the venous side of the cardiopulmonary bypass circuit. As a result, continuous blood glucose monitoring using an artificial endocrine pancreas was proven to be stable and reliable during cardiovascular surgery involving cardiopulmonary bypass.

  16. Adherence to treatment after coronary bypass surgery: Psychological aspects

    Directory of Open Access Journals (Sweden)

    Maria V. Iakovleva

    2016-01-01

    Full Text Available Poor adherence to treatment is a problem of great importance and striking magnitude. Its consequences are increased health care costs and poor health outcomes. It defined the objective of this research, which is the study of psychological characteristics of patients with different degrees of adherence to rehabilitation treatment after coronary bypass surgery. Ninety male and female patients with CHD, aged 46---71, were examined. The study was carried out using the questionnaire of ways of coping and the technique for diagnosing the types of attitude toward the disease, and the study of medical history. The analysis of the types of attitude toward the disease revealed that adherent patients show higher values on the harmonious type; patients with poor adherence show higher values on the apathetic, as well as the melancholic type of attitude toward illness. This study shows that wide range of psychological characteristics is significant for the definition of adherence to treatment. It is essential to consider the patient’s personality and his characteristics, such as attitude toward the disease, because they influence the adherence and, therefore, the effectiveness of therapy in the postoperative period. La escasa adherencia a la terapia es un problema de gran importancia ampliamente extendido. Sus consecuencias son el aumento de costes del tratamiento y su baja eficacia. El objetivo de la investigación fue el estudio de las características psicológicas de pacientes con diferentes grados de adherencia al tratamiento de rehabilitación después de la cirugía de derivación coronaria. Se recogieron datos clínicos de 90 pacientes de ambos sexos con cardiopatía coronaria, sometidos a cirugía de derivación coronaria, con edades comprendidas entre 46-71 a˜nos. Los cuestionarios administrados fueron el cuestionario de estilos de afrontamiento y la técnica de diagnóstico de tipos de actitud hacia la enfermedad. Además se realizó un estudio

  17. Dopexamine increases internal mammary artery blood flow following coronary artery bypass grafting.

    LENUS (Irish Health Repository)

    Flynn, Michael J

    2012-02-03

    OBJECTIVE: Vasoactive agents and inotropes influence conduit-coronary blood flow following coronary artery bypass grafting (CABG). It was hypothesized that dopexamine hydrochloride, a dopamine A-1 (DA-1) and beta(2) agonist would increase conduit-coronary blood flow. A prospective randomized double blind clinical trial was carried out to test this hypothesis. DA-1 receptors have previously been localized to human left ventricle. METHODS: Twenty-six American Society of Anaesthesiology class 2-3 elective coronary artery bypass graft patients who did not require inotropic support on separation from cardiopulmonary bypass (CPB) were studied. According to a randomized allocation patients received either dopexamine (1 microg\\/kg per min) or placebo (saline) by intravenous infusion for 15 min. Immediately prior to and at 5,10 and 15 min of infusion, blood flow through the internal mammary and vein grafts (Transit time flow probes, Transonic Ltd.), heart rate, cardiac index, mean arterial pressure and pulmonary haemodynamics were noted. The data were analysed using multivariate analysis of variance. RESULTS: Low-dose dopexamine (1 microg\\/kg per min) caused a significant increase in mammary graft blood flow compared to placebo at 15 min of infusion (P=0.028, dopexamine group left internal mammary artery (LIMA) flow of 43.3+\\/-14.2 ml\\/min, placebo group LIMA flow at 26.1+\\/-16.3 ml\\/min). Dopexamine recipients demonstrated a non-significant trend to increased saphenous vein graft flow (P=0.059). Increased heart rate was the only haemodynamic change induced by dopexamine (P=0.004, dopexamine group at 85.2+\\/-9.6 beats\\/min and placebo group at 71.1+\\/-7.6 beats\\/min after 15 min of infusion). CONCLUSION: This study demonstrates that administration of dopexamine (1 microg\\/kg per min) was associated with a significant increase in internal mammary artery graft blood flow with mild increase in heart rate being the only haemodynamic change. Low-dose dopexamine may

  18. Postoperative neuropsychological change and its underlying mechanism in patients undergoing coronary artery bypass grafting

    Institute of Scientific and Technical Information of China (English)

    YIN Yi-qing; LUO Ai-lun; GUO Xiang-yang; LI Li-huan; HUANG Yu-guang

    2007-01-01

    Background The high incidence of neuropsychologic deficits after cardiac surgery, including cognitive dysfunction and mood status, has significantly influenced the prognosis, outcome of treatment and long-term quality of life of patients. With a circadian secretion pattern, melatonin and cortisol are capable of modulating the human physiological processes and neuropsychological status, whereas disorder of their secretion pattern may lead to many diseases. However, it is unclear whether neuroendocrine variations are related to the neuropsychologic status in patients undergoing coronary artery bypass grafting (CABG). Methods Forty male patients scheduled for CABG with hypothermic cardiopulmonary bypass (CPB) (n=20) or off-pump coronary artery bypass (OPCAB) (n=20) were studied. Blood samples were taken intraoperatively at specific time-points and every 3 hours within the first postoperative 24 hours to determine plasma concentrations of melatonin and cortisol. A neuropsychologic test battery including depression and anxiety was administered preoperatively and 7 to 10 days postoperatively. Statistical methods included the nonparametric analysis, multiple linear regression and cosinor analysis. Results The patients in the CPB group exhibited more severe neuropsychologic deficits and more anxious than those in the OPCAB group after surgery. In both groups, patients were more depressed postoperatively than preoperatively and recovered 3 months after surgery. Depression and anxiety were correlated with some factors of cognitive dysfunctions. In the postoperative 24 hours, 2 patients in the CPB group, and 6 patients in the OPCAB group showed a circadian rhythm of melatonin secretion. As for cortisol secretion, there were 3 patients in the CPB group and 7 in the OPCAB group respectively. Parameters of circadian rhythm of melatonin in the CPB group and those of secretion rhythm of cortisol in both groups were correlated with depression and some neuropsychologic tests

  19. 78 FR 77430 - Proposed Information Collection; Comment Request; Foreign Fishing Vessel Permits, Vessel, and...

    Science.gov (United States)

    2013-12-23

    ... fishery or joint venture operation, transship fish harvested by a U.S. vessel to a location outside the U... fishing vessels that participate in a directed fishery or a joint venture operation. In particular these... fishing, participation in joint ventures with U.S. vessels, or transshipments of fish or fish...

  20. Retinal vessel diameters and cerebral small vessel disease: the Rotterdam Scan Study

    NARCIS (Netherlands)

    Ikram, M.K.; Jong, F.J. de; Dijk, E.J. van; Prins, N.D.; Hofman, A.; Breteler, M.M.B.; de Jong, P.T.V.M.

    2006-01-01

    The direct visualization of retinal vessels provides a unique opportunity to study cerebral small vessel disease, because these vessels share many features. It was reported that persons with smaller retinal arteriolar-to-venular ratio tended to have more white matter lesions on MRI. It is unclear wh

  1. Final report for confinement vessel analysis. Task 2, Safety vessel impact analyses

    Energy Technology Data Exchange (ETDEWEB)

    Murray, Y.D. [APTEK, Inc., Colorado Springs, CO (United States)

    1994-01-26

    This report describes two sets of finite element analyses performed under Task 2 of the Confinement Vessel Analysis Program. In each set of analyses, a charge is assumed to have detonated inside the confinement vessel, causing the confinement vessel to fail in either of two ways; locally around the weld line of a nozzle, or catastrophically into two hemispheres. High pressure gases from the internal detonation pressurize the inside of the safety vessel and accelerate the fractured nozzle or hemisphere into the safety vessel. The first set of analyses examines the structural integrity of the safety vessel when impacted by the fractured nozzle. The objective of these calculations is to determine if the high strength bolt heads attached to the nozzle penetrate or fracture the lower strength safety vessel, thus allowing gaseous detonation products to escape to the atmosphere. The two dimensional analyses predict partial penetration of the safety vessel beneath the tip of the penetrator. The analyses also predict maximum principal strains in the safety vessel which exceed the measured ultimate strain of steel. The second set of analyses examines the containment capability of the safety vessel closure when impacted by half a confinement vessel (hemisphere). The predicted response is the formation of a 0.6-inch gap, caused by relative sliding and separation between the two halves of the safety vessel. Additional analyses with closure designs that prevent the gap formation are recommended.

  2. The role of bypass diodes in the failure of solar battery charging stations in Thailand

    Energy Technology Data Exchange (ETDEWEB)

    Greacen, C.; Green, D. [Energy and Resources Group, 310 Barrows Hall no. 3050, University of California, 94720-3050 Berkeley, CA (United States)

    2001-12-15

    This paper focuses on the failure of bypass diodes in solar battery charging stations (SBCS) in Thailand. The Thai government has installed over 1000 SBCS in unelectrified villages to be used to charge 12-V batteries for household lights and small appliances. The unnecessary inclusion of bypass diodes in these systems created an unexpected failure mode when villagers misconnected their batteries with reverse polarity. In a survey of 31 stations, 18 stations were disabled by burnt-out bypass diodes. The electrical engineering theory of this failure mode is analyzed. In addition, we discuss how the bypass diode failures have been compounded by lack of end-user feedback to the implementing agencies.

  3. AUTOMATIC RETINAL VESSEL DETECTION AND TORTUOSITY MEASUREMENT

    Directory of Open Access Journals (Sweden)

    Temitope Mapayi

    2016-07-01

    Full Text Available As retinopathies continue to be major causes of visual loss and blindness worldwide, early detection and management of these diseases will help achieve significant reduction of blindness cases. However, an efficient automatic retinal vessel segmentation approach remains a challenge. Since efficient vessel network detection is a very important step needed in ophthalmology for reliable retinal vessel characterization, this paper presents study on the combination of difference image and K-means clustering for the segmentation of retinal vessels. Stationary points in the vessel center-lines are used to model the detection of twists in the vessel segments. The combination of arc-chord ratio with stationary points is used to compute tortuosity index. Experimental results show that the proposed K-means combined with difference image achieved a robust segmentation of retinal vessels. A maximum average accuracy of 0.9556 and a maximum average sensitivity of 0.7581 were achieved on DRIVE database while a maximum average accuracy of 0.9509 and a maximum average sensitivity of 0.7666 were achieved on STARE database. When compared with the previously proposed techniques on DRIVE and STARE databases, the proposed technique yields higher mean sensitivity and mean accuracy rates in the same range of very good specificity. In a related development, a non-normalized tortuosity index that combined distance metric and the vessel twist frequency proposed in this paper also achieved a strong correlation of 0.80 with the expert ground truth.

  4. Analyzing Vessel Behavior Using Process Mining

    NARCIS (Netherlands)

    Maggi, F.M.; Mooij, A.J.; Aalst, W.M.P. van der

    2013-01-01

    In the maritime domain, electronic sensors such as AIS receivers and radars collect large amounts of data about the vessels in a certain geographical area. We investigate the use of process mining techniques for analyzing the behavior of the vessels based on these data. In the context of maritime sa

  5. Supply vessel operations in a harsh environment

    Energy Technology Data Exchange (ETDEWEB)

    Strong, R. [Seabase Ltd., St. John' s, NF (Canada)

    2004-07-01

    Supply vessel contracts provide a range of services for multi-purpose supply vessels (MPSV) and anchor handling tug supply (AHTS) vessels. The features of both types of vessels were presented along with the key challenges to meet operational expectations, particularly in harsh environments. The successes and accomplishments for Seabase/Maersk in Atlantic Canada were reviewed. The work role of Seabase Ltd. is to ensure safety in offshore cargo operations, anchor handling, rig move operations, iceberg management, sub-sea support operations, and environmental response operations such as oil boom deployment. Seabase Ltd. also monitors other environmental factors such as icing, visibility, wind speed, sea height, and weather conditions. Seabase/Maersk currently provides contracts to 8 supply vessels that are actively working in east coast Canada. In 2003 there were no lost time accidents. figs.

  6. Influence on adipose tissue insulin resitance of type 2 diabetic rats after gastric bypass operation%胃转流术对2型糖尿病大鼠脂肪组织胰岛素抵抗的影响

    Institute of Scientific and Technical Information of China (English)

    温雨晴; 谭迎春; 张蓬波; 吕墩涛; 任泽强

    2013-01-01

    目的 观察胃转流术(GBP)对2型糖尿病(T2DM)大鼠脂肪组织胰岛素受体底物1(IRS-1)、磷酸肌醇3激酶(PI3K)蛋白表达的影响,探讨GBP改善胰岛素抵抗的机制.方法 将36只T2DM SD大鼠随机分为手术组(T组)、饮食控制组(F组)和糖尿病对照组(C组),每组12只.术前及术后第1、2、4、8周测空腹血糖(FPG)、空腹胰岛素(FINS)并计算术前及术后第8周胰岛素敏感指数(QUICKI),Western blot检测各组术后第8周脂肪组织IRS-1、PI3K蛋白的表达.结果 与术前和同时间点对照组比较,GBP手术组大鼠FPG术后第1周开始降低,至术后第8周时T组大鼠FPG由术前的(17.28 ±2.15) mmol/L降至(5.79±1.83) mmol/L(P <0.05);T组大鼠FINS经历了先升后降的过程,至第8周时FINS降至(7.69±1.73) mU/L(P<0.05);QUICKI在术后第8周时高于术前及对照组(P<0.05);手术组IRS-1、PI3K表达水平均显著高于对照组(P<0.05).结论 GBP可改善脂肪细胞IRS-1/PI3K胰岛素信号转导通路,纠正脂肪细胞的胰岛素抵抗,提高T2DM大鼠的胰岛素敏感性.%Objective To investigate the expressions of insulin receptor substrate-1 (IRS-1) and phosphatidylinositol 3 kinase (PI3K) in adipose tissue of type 2 diabetic rats after gastric bypass operation,and to study the possible mechanism of adipose tissue insulin resitance.Methods Thirty-six type 2 diabetic SD rats were randomly divided into 3 experimental groups:Gastric bypass operation group (T group),food control group (F group),type 2 diabetes rats control group (C group),12 rats in each group.Plasma glucose concentration,insulin,were measured in preoperative and postoperative at week 1,2,4 and 8.Quantitative insulin sensitivity check index (QUICKI) were measured in preoperative and postoperative at week 8.And the protein of adipose tissue IRS-1and PI3K were measured at week 8 after operative.Results The fasting blood glucose of T group rats at the first week were so obviously lower than F and

  7. Evaluation of the In-vessel Downstream Effects for the APR1400 Design and License

    Energy Technology Data Exchange (ETDEWEB)

    Suh, Jeong-kwan; Kim, Jae-won; Kwon, Sun-guk; Lee, Jae-yong [KHNP Central Research Institute, Daejeon (Korea, Republic of)

    2015-10-15

    These reports include the licensing issues as follows; the effect of a flow channel gap change, the effect of debris settling, the accuracy of the GF630 flow meter, the effect of bubbles impinging on the bottom nozzle, and the bypass fiber amount. In this paper, the valuation results of the in-vessel downstream effects for the APR1400 were described. In addition, the effect of a flow channel gap change and the bypass fiber amount were evaluated. In-vessel downstream effect tests with a mock-up PLUS7 fuel assembly were performed to confirm that the head losses caused by debris meet the available driving head following a LOCA. All the test results showed lower pressure drops than the available head limits. Therefore, a sufficient driving force is available to maintain an adequate flow rate, and the LTCC capability is adequately maintained in the APR1400. A sensitivity test was conducted to assess the effect of a change in the gap size between the mock-up fuel assembly and the test column. The maximum pressure drop recorded for the test was 19.73 kPa under the re-manufactured condition. This value is larger by 1.6% than the previous test result (19.4 kPa) under the same conditions. As such, changing the gap of the flow path between the mock-up fuel assembly and the test column from the previous manufactured conditions to the re-manufactured conditions is expected to result in a slight increase in the differential pressure. However, this is a negligible amount compared to the test uncertainty value of 25%.

  8. Electroencephalography during surgery with cardiopulmonary bypass and hypothermia.

    Science.gov (United States)

    Bashein, G; Nessly, M L; Bledsoe, S W; Townes, B D; Davis, K B; Coppel, D B; Hornbein, T F

    1992-06-01

    After more than 30 yr of use, electroencephalographic (EEG) monitoring during cardiopulmonary bypass has not gained wide clinical acceptance. To assess its utility to predict central nervous system injury, two-channel recordings were made from 78 patients undergoing cardiopulmonary bypass and anesthetized with fentanyl/diazepam/enflurane. The perfusion regimen included the use of high pump flow, a bubble oxygenator, and no arterial tubing filter. Target values were 28-32 degrees C for the minimum rectal temperature, 60-80 mmHg for mean arterial pressure, and 20-25% for hematocrit. Eight descriptors of the Fourier power spectra of the EEG were calculated off-line, and outcome comparisons were made with the results from neuropsychological tests. Among 58 patients yielding complete data of acceptable quality, a statistically significant reduction in total power was observed from prebypass to postbypass, accompanied by an increase in the fractional power in the theta and beta frequency bands and in the spectral edge frequency. The shifts in total and theta power were weakly associated with short-term but not with long-term changes in neuropsychological scores. Nearly 40% of the patients' EEGs were corrupted with electrical noise at some time during bypass. In 15 patients selected for having high-quality recordings and no neuropsychological deficit, an extensive statistical analysis failed to reveal any consistent variation in the EEG descriptors with hypothermia. Under the conditions studied, it appears that for other than gross signal dropout, the strong background variability in the EEG makes it have little value for detecting harbingers of brain injury.

  9. Hospitalization before and after mini-gastric bypass surgery.

    Science.gov (United States)

    Rutledge, Robert

    2007-02-01

    The mini-gastric bypass (MGB) was developed to address some of the limitations of the Roux-en-Y gastric bypass ("RNY"). The RNY has recently been reported to increase the need for hospitalization for complications after RNY surgery. To determine the rates and indications for inpatient hospital use before and after MGB in comparison to similar rates in RNY. The study is a self reported retrospective study of patients from across the United States receiving MGB in Centers for Excellence in Laparoscopic Obesity Surgery ("CELOS") hospitals from 2000 to 2005. Complications and hospitalization in the year before and in the 1 to 5 years after MGB. 1069 patients who underwent MGB were selected for study. The rate of hospitalization in the year following MGB was 67% of the rate in the year preceding MGB (11% vs. 17%, P<0.001). The most common reasons for admission prior to MGB were general medical problems (38%) obstetric and Gynecological issues (36%), orthopedic problems (16%), gallbladder surgery (9%) and renal stones in 2%. The most common reasons for hospital admission after MGB were complications from surgery (29%), gallbladder surgery (20%), renal stones (14%), plastic surgery procedures (11%), appendectomy (9%), Gynecologic issues (9%) and orthopedic problems (6%). Thus while MGB complications made up a third of hospital readmissions following MGB surgery the over all hospitalization rates declined significantly. Previous studies have demonstrated that hospitalization after RNY gastric bypass increases remarkably (20% per year). The present study shows that hospitalization following MGB instead of rising, as reported with RNY, decreases by a third. The MGB has been shown to be a short, safe successful weight loss surgery in previous work. The present study supports the MGB as a low risk procedure that decreases the need for hospitalization.

  10. 36 CFR 13.1154 - Commercial vessel permits and conditions.

    Science.gov (United States)

    2010-07-01

    ...) A tour vessel, charter vessel, and passenger ferry must have a commercial authorization to operate in Glacier Bay. (c) The operator of a cruise ship, tour vessel, charter vessel, and passenger ferry... advance of entering Glacier Bay or immediately upon entry. (d) Cruise ships and tour vessels...

  11. Cryosurgical effects on growing vessels.

    Science.gov (United States)

    Ladd, A P; Rescorla, F J; Baust, J G; Callahan, M; Davis, M; Grosfeld, J L

    1999-07-01

    Cryosurgical treatment of unresectable hepatic malignancies has proven beneficial in adults. Concerns regarding its use in children include the effect on growth and the risk of injury to adjacent structures. To test the effect of cryoablation on adjacent vascular structures in a growing animal, liquid nitrogen cryoablation was performed on a juvenile murine model. Sprague Dawley rats underwent double freeze-thaw cryoablation of the abdominal aorta with interposed liver tissue. Serial sacrifices were performed over 120 days. Comparisons were made with sham-operated controls. Overall, animal growth paralleled that of sham controls through all time points. Gross examination of aortic diameter also showed similar growth in vessel size between the groups. Histologic analysis demonstrated injury after cryoablation with smooth muscle cell vacuolization, followed by cell death. Aortic media layer collapse resulted from cellular loss, however, elastin fiber composition was maintained. Aortic patency was preserved despite evidence of cellular injury and aortic wall remodeling. An associated thermal sink effect on the opposing wall was identified. After cryoablation adjacent to the abdominal aorta in adolescent rats, vascular patency is maintained and animal growth and structural function is preserved, despite cellular injury and wall compression. These observations suggest that cryoablation may be a useful treatment adjunct in young subjects.

  12. Popular Hybrid Congenital Heart Procedures without Cardiopulmonary Bypass

    Science.gov (United States)

    Gupta, Aamisha; Amin, Zahid

    2017-01-01

    As surgical and catheter interventions advance, patients with congenital heart disease are now offered alternative treatment options that cater to their individual needs. Furthermore, collaboration between interventional cardiologists and cardiac surgeons have led to the development of hybrid procedures, using the best techniques of each respective field to treat these complex cardiac entities from initial treatment in the pediatric patient to repeat intervention in the adult. We present a review of the increased popularity and trend in hybrid procedures in congenital heart disease without the use of cardiopulmonary bypass.

  13. Epidemiologic Surveillance for Staphylococcus epidermidis infections related to cardiopulmonary bypass.

    Science.gov (United States)

    Lathrop, G D; Brockett, R M; Blouse, L E

    1978-07-01

    Epidemiologic investigation of 20 Staphylococcus infections among valvular and aortocoronary bypass graft patients indicated a broad spectrum of clinical illness in these two groups. The highest infection rate (9.3%) and case specific mortality rate (54.5%) were noted among those patients undergoing cardiovalvular replacement surgery with protheses. The median onset of infection was 6 days suggesting infection during the intraoperative period. Using the epidemiologic data from this investigation, a transmission pattern was formulated and a series of control measures designed to interdict the routes of transmission were instituted wigh marked success. These measures significantly reduced the incidence of S. epidermidis infections among these high risk patients.

  14. Lower leg electrical impedance after distal bypass surgery

    DEFF Research Database (Denmark)

    Belanger, G K; Bolbjerg, M L; Heegaard, N H

    1998-01-01

    Electrical impedance was determined in 13 patients following distal bypass surgery to evaluate lower leg oedema as reflected by its circumference. Tissue injury was assessed by the plasma concentration of muscle enzymes. After surgery, the volume of the control lower leg increased from 1250 (816...... of troponin I (n = 8). In conclusion, tissue injury was reflected by increases in muscle enzymes in plasma. We found an inverse correlation between lower leg electrical impedance and volume, but the deviation in electrical impedance was approximately twice that of the leg volume. Electrical impedance appears...

  15. Transient cortical blindness and successful recovery after coronary bypass surgery.

    Science.gov (United States)

    Tasdemir, Kutay; Evereklioglu, Cem; Kaya, Mehmet G

    2011-10-01

    Left ventricular injury has a bad prognosis, especially when a coronary artery is involved. After perforation of the left cardiac ventricle by a knife, a 19-year-old male patient presented with: (i) complete bilateral visual loss; (ii) left anterior descending (LAD) artery injury; (iii) severe systemic hypotension. Under emergency conditions and cardiopulmonary bypass, the LAD artery was revascularized by a saphenous vein graft. Bilateral blindness recovered within several days. Cerebral hypoxia as a result of severe systemic hypotension was the most likely underlying mechanism.

  16. Sen perforation af tyndtarm efter laparoskopisk gastrisk bypass

    DEFF Research Database (Denmark)

    Spanager, Lene; Sigild, Ulf Henrik; Neuenschwander, Anders Ulrich

    2010-01-01

    We present two cases in which the patients were admitted to a local hospital with acute abdominal pain four or five months after having undergone laparoscopic gastric bypass. In both cases, operation revealed a perforation of the small bowel close to the distal anastomosis. In the first case......, a massive constipation of the small bowel was most likely a contributing factor. In the second case, the cause was a kink of the entero-entero anastomosis leading to obstruction and finally perforation of the biliary limp. Late perforations are among the rarely reported complications associated with gastric...

  17. Quality of life-associated factors among patients undergoing coronary artery bypass surgery as measured using the WHOQOL-BREF.

    Science.gov (United States)

    Najafi, Mahdi; Sheikhvatan, Mehrdad; Montazeri, Ali

    2009-01-01

    This was a study of the pre-operative factors that influence quality of life (QoL) in patients with coronary artery disease and the relationship between pre-operative QoL and early outcome after coronary artery bypass surgery (CABG). Using the WHOQOL-BREF questionnaire, 283 patients who underwent isolated coronary artery bypass surgery were interviewed and scores were obtained for the physical, psychological, social and environmental components. The study found that the independent physical component predictors for higher QoL included male gender and diabetes mellitus, while the independent psychological component predictors were male gender and high ejection fraction. Males, diabetics and patients with low education levels had higher social well-being than others. Among the postoperative complications, only respiratory failure was found to have a relationship with physical and psychological components. Women with coronary artery disease who were candidates for CABG had lower scores than the men in respect of all components of QoL. Furthermore, a lower pre-operative psychological score in patients undergoing CABG can influence postoperative complications, especially respiratory failure.

  18. In vivo performance of the polyesterurethane Vascugraft prosthesis implanted as a thoraco-abdominal bypass in dogs: an exploratory study.

    Science.gov (United States)

    Zhang, Z; King, M W; Marois, Y; Marois, M; Guidoin, R

    1994-10-01

    Among the various prototype vascular prostheses that have been developed over recent years as small vessel substitutes, the Vascugraft polyurethane device produced by Braun-Melsungen AG has a number of attractive features. As well as having high mechanical compliance similar to that of the arterial tree, it has been manufactured from a specially synthesized poly(ester urethane) with improved biostability and its microfibrous structure provides a highly porous wall with open communicating pores. With a view to evaluating the in vivo biofunctionality and biostability of this prosthesis in the dog, 10 mm diameter grafts were implanted as thoraco-abdominal bypasses for prescheduled periods of 1 months and 12 months, and their performance monitored in terms of gross morphology, histology and the measurement of the chemical and physical properties of the explanted and cleaned specimens. Both grafts were patent at retrieval. Each had a smooth and glistening flow surface without organized mural thrombi and showed the development of a thin collagenous internal capsule with the presence of endothelial-like cells. Both grafts were well encapsulated externally and revealed a small distal bend or kink which is frequently observed by any thoraco-abdominal bypass in dogs. The fresh explanted prostheses were cleaned by a new enzyme treatment which provided specimens for microscopic, mechanical and thermal analyses, as well as studies of the surface and bulk chemistry. By comparing the results from the explanted and cleaned material with those of the virgin prosthesis, we have observed some deterioration in the integrity of the microfibrous structure, some loss in mechanical performance, marginal changes in molecular weight, and an apparent microphase separation of the hard and soft segment domains at a depth of a few microns. While the biofunctionality of a 10 mm calibre device has been demonstrated, additional in vivo studies are recommended to assess the biofunctionality at

  19. Fuel temperature prediction using a variable bypass gap size in the prismatic VHTR

    Energy Technology Data Exchange (ETDEWEB)

    Lee, Sung Nam, E-mail: snlee@kaeri.re.kr; Tak, Nam-il; Kim, Min Hwan

    2016-04-15

    Highlights: • The bypass flow of the prismatic very high temperature reactor is analyzed. • The bypass gap sizes are calculated considering the effect of the neutron fluences and thermal expansion. • The fuel hot spot temperature and temperature profiles are calculated using the variable gap size. • The BOC, MOC and EOC condition at the cycle 07 and 14 are applied. - Abstract: The temperature gradient and hot spot temperatures were calculated in the prismatic very high temperature reactor as a function of the variable bypass gap size. Many previous studies have predicted the temperature of the reactor core based on a fixed bypass gap size. The graphite matrix of the assemblies in the reactor core undergoes a dimensional change during the operation due to thermal expansion and neutron fluence. The expansion and shrinkage of the bypass gaps change the coolant flow fractions into the coolant channels, the control rod holes, and the bypass gaps. Therefore, the temperature of the assemblies may differ compared to those for the fixed bypass gap case. The temperature gradient and the hot spot temperatures are important for the design of reactor structures to ensure their safety and efficiency. In the present study, the temperature variation of the PMR200 is studied at the beginning (BOC), middle (MOC), and end (EOC) of cycles 07 and 14. CORONA code which has been developed in KAERI is applied to solve the thermal-hydraulics of the reactor core of the PMR200. CORONA solves a fluid region using a one-dimensional formulation and a solid region using a three-dimensional formulation to enhance the computational speed and still obtain a reasonable accuracy. The maximum temperatures in the fuel assemblies using the variable bypass gaps did not differ much from the corresponding temperatures using the fixed bypass gaps. However, the maximum temperatures in the reflector assemblies using the variable bypass gaps differ significantly from the corresponding temperatures

  20. Coronary artery bypass graft imaging using ECG-gated multislice computed tomography: Comparison with catheter angiography

    Energy Technology Data Exchange (ETDEWEB)

    Moore, R.K.G. [Cardiothoracic Centre, Liverpool (United Kingdom)]. E-mail: moore@roger.go-legend.net; Sampson, C. [Cardiothoracic Centre, Liverpool (United Kingdom); MacDonald, S. [Cardiothoracic Centre, Liverpool (United Kingdom); Moynahan, C. [Cardiothoracic Centre, Liverpool (United Kingdom); Groves, D. [National Refractory Angina Centre, Liverpool (United Kingdom); Chester, M.R. [National Refractory Angina Centre, Liverpool (United Kingdom)

    2005-09-01

    AIM: To compare the value of multislice computerized tomography (MSCT) in imaging coronary artery bypass grafts (CABGs) by direct quantitative comparison with standard invasive angiography. METHODS: Using MSCT, 50 consecutive patients who had previously undergone CABG surgery and had recently undergone invasive angiography for recurrent angina pectoris, were studied further using MSCT after intravenous injection of non-ionic contrast agent; cardiac imaging was performed during a single breath-hold. Graft anatomy was quantified, using both quantitative coronary angiography (QCA) and MSCT, by different investigators blinded to each other. Reproducibility was quantified using the standard error of the measurement expressed as a percentage in log-transformed values (CV%) and intraclass correlation (ICC). RESULTS: All 150 grafts were imaged using MSCT; only 4 patent grafts were not imaged using selective angiography. Good agreement was achieved between MSCT and QCA on assessment of proximal anastomoses (CV% 25.2, ICC 0.84), mid-vessel luminal diameter (CV% 15.5, ICC 0.91) and aneurysmal dilations (CV% 14.3). Reasonable agreement was reached on assessment of distal anastomoses (CV% 26.7, ICC 0.66) and categorization of distal run-off (ICC 0.73). Good agreement was observed for stenoses of over 50% luminal loss (CV% 8.7, ICC 0.97) but agreement on assessment of less severe lesions was poor (CV% 208.7, ICC 0.51). CONCLUSION: This study demonstrates that CABGs can be quantitatively evaluated using MSCT, and that significant lesions present in all CABG segments can be reliably identified. Agreement between MSCT and QCA for lesions of less than 50% luminal loss was poor.