In order to study effect of endothelin (ET-1) on hepatic blood flow in rats and effect of nitric oxide (NO) and prostacyclin (PGI2) on ET-1 biological function, 20 rats were randomized into control, ET-1, ET-1 plus nitric-Larginine, ET-1 plus prostacyclin and indomethen groups. The result showed that ET-1 decreased hepatic blood flow and lasted for longer time. NO and PGI2 may antagonize the biological action of ET-1 during endotoxemia. Therefore, the endothelium-derived vascular factors may regulate hepatic blood flow.
Objective To investigate the long effect of nonpulsatile flow on changes of structure and function in pulmonary microcirculation and to identify the pulmonary reconstruction under this blood perfusion. Methods Canine models with nonpulsatile flow in the right lung was established, and sacrificed 6 months later. Compare endothelial nitric oxide synthase (eNOS) in vascular endothelium, apoptosis in smooth muscle cell with immunohistochemistry by streptavidinbioepidermmultienzyme complex methodes, and observe structural changes in pulmonary arterioles with optical microscope. Results The expression of eNOS in the right nonpulsatile flow perfusing lung was weaker as compared to the left lung （10 846.7±177.8 vs. 13 136.1±189.6;t＝2.240, P=0.040）, the fas was ber as compared to the left lung（14 254.1±217.1 vs. 11 976.7±195.7; t＝2.160, P=0.040）. The ratio of wall thichness/vessel diameter in the right lung（13.64%±12.80% vs. 14.96%±13.10%） and wall area/vessel area(46.40%±11.70% vs. 47.80%±12.20%) was lower as compared to the left lung(Plt;0.05). Conclusion Longterm nonpulsatile flow can decrease the expression of eNOS, contract the muscles in capillary net, and increase pulmonary vascular resistance. Moreover it canincrease the arteriole apoptosis, leading to vascular structure remodeling.
In order to investigate the influence on the blood flow direction and pattern at the arterial bifurcation, the mesenteric arterioles of 19 SD rats were observed under the OLYMPUS BH2 surgical microscope. After the rats were anesthetized and the body temperature was kept at 37℃ to 38℃, the mesenteric membrane wasexposed and the pattern and direction of the blood flow of the arterioles whichbifurcated at angle of 45±5°, 90±5° and 135±5° were observed. Results showed that the deformation of RBCs made them easy to adapt to the intravascular geometry and pass by fluently without sticking. It was implied that the alteration in arterial flow direction did not cause turbulance at the bifurcation site, and this in return suggested that in end-to-side anastomosis of small arteries,the flow volume would not be reduced and the chance of thrombosis would not be increased.
Abstract An animal experiment had been conducted for the purpose to find out the possibility of application of instantaneous sustained limited expansion (ISLE). A total of 54 skin defects in 9 pigs were obtained and were divided into two groups. One group of the pigs were subjected to instantaneous sustained limited expansion, the others, as the control group, just received the tension suture. At the same time the blood supply of the skin was measured by laser doppler flowmeter (LDF). It was showed that microcirculatory perfusion of the ISLE group was considerably better than that of the control. Inaddition, the correlation between the blood flow of the skin and the expanding pressure, as well as the pathologic changes of the skin were discussed.
Objective To evaluate hepatic functional reserve and investigate the clinical value through measuring hepatic functional blood flow by D-sorbitol clearance rate and liver volume changes with CT. Methods Ninety-two patients with portal hypertension due to posthepatic cirrhosis were investigated (cirrhosis group). Twenty healthy volunteers were used as control group. D-sorbitol was infused intravenously at a steady rate. Blood and urine were collected and recorded once before infusion and at 120, 150 and 180 min after infusion, and their concentrations of D-sorbitol were examined by enzyme spectrophotometry. From pharmacokinetic equations, hepatic clearance rate of D-sorbitol (CLH) was calculated. Total hepatic blood flow (QTOTAL) was measured by Doppler sonography, intrahepatic shunt rate (RINS) was obtained. The liver volume change rate was obtained in patients with cirrhosis through the abdominal CT scan. The relations among the indicators, Child classification and postoperative complications were studied. Results After D-sorbitol was infused intravenously for 120 min, the plasma concentration was at the steady state. The plasma concentration was (0.189±0.05) mmol/L in control group and (0.358±0.06) mmol/L in cirrhosis group (Plt;0.01). CLH was (1 248.3±210.5) ml/min in control group and (812.7±112.4) ml/min in cirrhosis group (Plt;0.01). Although QTOTAL in cirrhosis group was declined, compared with the control group 〔(1 280.6±131.4) ml/min vs. (1 362.4±126.9) ml/min〕, Pgt;0.05, while RINS increased markedly 〔(36.54±10.65)% vs. (8.37±3.32)%, Plt;0.01〕. In cirrhosis group, the mean liver volume of Child A, B and C patients were (1 057±249) cm3, (851±148) cm3 and (663±77) cm3 respectively. There were significant differences among the mean liver volume (Plt;0.05). The liver volume was significantly smaller in Child B and C patients than that in Child A (Plt;0.05, Plt;0.01). When CLH was less than 600 ml/min, and liver volume decreased by more than 40%, postoperative complications increased significantly. CLH and the liver volume change rate were not in absolutely good accordance with Child classification. Conclusion The hepatic clearance of D-sorbitol and the quantitative determination of the liver volume with CT can be an objective evaluation of the liver metabolism of the inherent capacity and the hepatic functional blood flow changes. It contributes to the correct understanding of the hepatic functional reserve and lay the foundation for determining a reasonable treatment plan, surgical methods and time.
ObjectiveTo summarize and share the surgical nursing experiences for hybrid procedures in the treatment of congenital heart disease with diminished pulmonary blood flow and aortopulmonary collateral arteries (APCA). MethodWe retrospectively analyzed the clinical data, including nursing problems, interventions and outcomes, of 15 patients with congenital heart disease with diminished pulmonary blood flow and APCA treated between May 2011 and February 2012. ResultsAll operations were completed successfully with effective nursing interventions. No complications like low cardiac output syndrome, lung over-perfusion, vital organ dysfunction, neuropsychological disorder, or systemic infection were noticed. ConclusionsHybrid procedure in the treatment of congenital heart disease with diminished pulmonary blood flow and APCA with complex surgical procedures, intraoperative variables and high surgical risks requires multi-disciplinary collaboration. Effective surgical nursing intervention is important to ensure the successful completion of surgery, and reduce possible complications.
The present research aims to point out the long-existing defect of analyzing the spectrum diagram only from the perspective of haemodynamics instead of haemorheology. In the light of the theories of haemodynamics and haemorheology, the causes of spectrum diagram formation of carotid artery blood at the rapid and slow flow can be clarified completely and accurately. Four conclusions have been drawn in the end. As long as the velocity gradient is large enough, obvious red blood cells concentrate to the shaft even in the big or bigger blood vessels; the spectrum diagram is the powerful proof of the two phase flow model of blood; the spectrum diagram can be completely and accurately analyzed only by combining haemodynamics with haemorheology; and only when the red blood cells concentrate to the shaft, the big or bigger blood vessels can be regarded as haemogeneous fluid.
The development and progression of atherosclerosis and thrombosis are closely related to changes of hemodynamics parameters. Ultrasonic pulse wave Doppler technique is normally used for noninvasively blood flow imaging. However, this technique only provides one-dimensional velocity and depends on the angle between the ultrasound beam and the local velocity vector. In this study, ultrasonic particle image velocimetry method was used to assess whole field hemodynamic changes in normal blood vessels. By using the polynomial fitting method, we investigated the velocity gradient and assessed the shear in different blood flow velocity of 10 healthy rats. It was found that using four polynomial fitting could result in optimal measurement results. The results obtained by ultrasonic particle image velocimetry accorded with the results obtained using Doppler technique. The statistical average of cyclical vessel wall shear stress was positively related to the locational mean velocity. It is proven that ultrasonic particle image velocimetry method could be used to assess directly the real-time whole field hemodynamic changes in blood vessels and was non-invasively, and should be a good prosperous technique for monitoring complex blood flow in stenotic arteries.
ObjectTo evaluate the feasibility of measuring the descending aortic blood flow using transesophageal ultrasound Doppler under cardiopulmonary bypass (CPB). MethodWe retrospectively analyzed the clinical data of 10 adult patients accepted elective cardiac surgery under CPB in March 2014 year. There were 4 males and 6 females with a mean age of 44.5±12.3 years ranging from 24.5-64.0 years. The descending aorta diameter and velocity time integral (VTI) of blood flow of middle esophageal and lower esophageal of these patients were detected by transesophageal echocardiography (TEE) under CPB. We took the formula of classic ultrasound texting the blood flow to calculate the descending aorta blood flow (DABF). At the same time, we recorded the data of CPB and index of hemodynamics. Compared with the flow of CPB pump, we analyzed the correlation between pump flow and the raliability of DABF texting value under CPB. ResultsTwo patients quit the trail for blurred imaging. The quality of blood flow spectrum images aquirded from the middle esophageal were inferior to those from the lower esophageal (P < 0.01) in the 10 patients. Among the patients 90% of DABF from the middle esophageal and 50% of DABF from the lower esophageal were more than pump flow. however, the texting value had an excellence correlation to PF (r=0.795, r=0.825). ConclusionThe classical TEE technique can not obtain accurate blood flow during CPB.
ObjectiveTo systematically review the efficacy and safety of hemihepatic blood flow occlusion versus Pringle's maneuver during hepatectomy. MethodsWe electronically searched The Cochrane Library (Issue 8, 2013), PubMed, EMbase, CBM, CNKI, VIP and WanFang Data for randomized controlled trials (RCTs) about hemihepatic blood flow occlusion versus Pringle's maneuver during hepatectomy. The duration of search was from the inception of the databases to August 2013. Meanwhile, references of the included studies were also retrieved. After literature selection, data extraction and quality assessment conducted by two reviewers independently, meta-analysis was conducted using RevMan 5.2 software. ResultsSeven studies involving 624 patients were finally included. The results of meta-analysis showed that: a) for safety, Pringle's maneuver was shorter than hemihepatic blood flow occlusion in operation time (SMD=0.34, 95%CI 0.02 to 0.66, P=0.04). But they were alike in intraoperative blood loss, transfusion requirements, hospitalization time, and complications. b) For effectiveness, Pringle's maneuver was lower than hemihepatic blood flow occlusion in the levels of 3rd day ALT (SMD=-0.71, 95%CI-1.28 to-0.14, P=0.02), 7th day ALT (SMD=-1.73, 95%CI-2.85 to-0.62, P=0.002), 1st day AST (SMD=-0.74, 95%CI-1.38 to-0.09, P=0.03), 7th day AST (SMD=-0.99, 95%CI-1.26 to-0.71, P < 0.000 01), 3rd day TBIL (SMD=-0.34, 95%CI-0.57 to-0.10, P=0.005), and 7th day TBIL (SMD=-0.52, 95%CI-1.02 to-0.01, P=0.04). ConclusionCompared to the Pringle's maneuver, hemihepatic blood flow occlusion during hepatectomy could promote the recovery of liver function. However, the number of the included RCTs in the review is small and the quality is low, some of the main information is not reported and the information for analysis lacks. Therefore, the aforementioned conclusion needs to be verified by conducting more large-scale, multicenter and high-quality RCTs.