【Abstract】ObjectiveTo compare the hemodynamic changes during operation of portal venous intubation or splenic venous intubation in extracorporeal venous bypass of swine orthotopic liver transplantation.MethodsThirty couples of healthy Duloke pigs were selected to perform orthotopic liver transplantation. According to the difference of cannula vessel of portal venous system during extracorporeal venous bypass, these pigs were divided into two groups: portal venous intubation group (n=15) and splenic venous intubation group (n=15). Hemodynamic changes were monitored continuously.ResultsTwo recipients died in portal venous intubation group, one died of unsmooth bypass in the operation, the other died of DIC. In splenic venous intubation group there was only one recipient death, who died of hemorrhagic shock. The time of anhepatic phase of splenic venous intubation group was (44.5±7.6) min, it was significantly shorter than portal venous intubation group(51.5±8.7) min(P＜0.05). Hemodynamic changes in phase Ⅲ and phase Ⅳ of portal venous intubation group were significantly different with that of splenic venous intubation group(P＜0.05). ConclusionApplication of bypass through splenic venous intubation during extracorporeal venous bypass of swine orthotopic liver transplantation can shorten the time of anhepatic phase, keep the hemodymamics relative stable in operation, and reduce the occurrence of postoperative correlative complication. It is an effective venovenous bypass pathway.
Objective To investigate the hemodynamic performance of valved bovine jugular vein conduits (BJVC) for right ventricular outflow tract reconstruction in canine model. Methods The BJVC that were treated with the glutaraldehyde were implanted between the pulmonary artery and right ventricle in seven young canines. Right ventricular and pulmonary artery pressures were measured directly before and after the implantation. Hemodynamic evaluations were carried out by echocardiography and cardiac catheterization after the implantation. Results Seven canines were survival one year after the implantation. The pulmonary artery pressures (including systolic pressure, diastolic pressure and mean pressure) had not significantly changed after reconstruction with the conduits. The right ventricular diastolic pressures had not increased after the reconstruction, but the right ventricular systolic pressure and mean pressure had increased. One year later, the echocardiography showed valve motion with no obvious thickening of the leaflets. No graft kinking or obvious regurgitation of the valve was observed. Cardiac catheterization and angiography showed that the pressure gradients between the right ventricle and the conduits varied from 3 to 19mmHg, the diastolic pressures in the conduits were higher than that of right ventricle((Plt;)0.01), and the conduits and pulmonary arteries had no obvious obstruction. Conclusion The glutaraldehyde-fixed bovine jugular vein conduit has good hemodynamic performance in the pulmonary circulation.
The hemodynamics changes of the common carotid arteries in 10 SD rats were measured with a color doppler flowmetry in an attempt to define the changes resulting from end-to-end anastomosis. The left common carotid arteries were divided and followed by end-to-end anastomosis. The systolic mean peak velocities in the left arteries were measured at the proximal, distal and anastomotic sites and in the right intact arteries as well at 6, 12, 24, 48, 72 and 120 hours after repair. The percentage of area reduction at anastomosis was calculated from these data. The results indicated that the systolic mean peak velocity at the anastomotic sites was significantly increased as compared to the velocity at the proximal, distal and contralateral sites (P lt; 0.05). The velocity at the distal sites was significantly lower than that from the proximal and contralateral sites (P lt; 0.05), the mean percentage of the reduction was 33.18% and 33.33%, respectively. From 6 hours to 120 hours after anastomosis of arteries there was various degree of narrowing at the site of anastomosis. The mean per cent of stenosis was 42.48%. It was concluded that from 6 to 120 hours after end-to-end anastomosis of the small arteries, the velocity at the anastomotic site was increased as compared to the velocities at pre- and post-anastomotic sites. The increase of velocity at the site of anatomosis was caused by stenosis at the anastomosis.
ObjectiveTo evaluate the effect of different doses of dexmedetomidine on hemodynamics during endotracheal extubation of laparoscopic cholecystectomy in patients with hypertension. MethodsA total of 120 hypertension patients ready to undergo laparoscopic cholecystectomy under general anesthesia between December 2013 and December 2014 were chosen to be our study subjects. They were randomly divided into 4 groups with 30 patients in each:saline control group (group C), low-dose dexmedetomidine hydrochloride injection group (group D1), moderate-dose dexmedetomidine hydrochloride injection group (group D2), and high-dose dexmedetomidine hydrochloride injection group (group D3). The anesthesia methods and drugs were kept the same in each group, and 20 mL of saline, 0.25, 0.50, 1.00 μg/kg dexmedetomidine (diluted to 20 mL with saline) were given to group C, D1, D2, and D3 respectively 15 minutes before the end of surgery. Time of drug administration was set to 15 minutes. We observed and recorded each patient's mean arterial pressure (MAP) and heart rate (HR) in 5 particular moments:the time point before administration (T1), immediately after administration (T2), extubation after administration (T3), one minute after extubation (T4), and 5 minutes after extubation (T5). Surgery time, recovery time, extubation time and the number of adverse reactions were also detected. ResultsCompared at with, MAP and HR increased significantly at the times points of T3, T4, T5 compared with T1 and T2 in Group C and group D1 (P<0.05), while the correspondent difference was not statistically significant in group D2 and D3 (P>0.05). Compared with group C, MAP and HR decrease were not significantly at the time points of T3, T4, T5 in group D1 (P>0.05). However, MAP and HR decrease at times points of T3, T4, T5 in group D2 and D3 were significantly different from group C and D1 (P<0.05). After extubation, there were two cases of dysphoria in group C and two cases of somnolence in group D3, but there were no cases of dysphoria, nausea or shiver in group D1, D2, D3. ConclusionIntravenously injecting moderate dose of dexmedetomidine 15 minutes before the end of surgery can effectively reduce patients' cardiovascular stress response during laparoscopic cholecystectomy extubation for patients with hypertension, and we suggest a dose of 0.5 μg/kg of dexmedetomidine.
It has been found that the incidence of cardiovascular disease in patients with lower limb amputation is significantly higher than that in normal individuals, but the relationship between lower limb amputation and the episodes of cardiovascular disease has not been studied from the perspective of hemodynamics. In this paper, numerical simulation was used to study the effects of amputation on aortic hemodynamics by changing peripheral impedance and capacitance. The final results showed that after amputation, the aortic blood pressure increased, the time averaged wall shear stress of the infrarenal abdominal aorta decreased and the oscillatory shear index of the left and right sides was asymmetrically distributed, while the time averaged wall shear stress of the iliac artery decreased and the oscillatory shear index increased. The changes above were more significant with the increase of amputation level, which will result in a higher incidence of atherosclerosis and abdominal aortic aneurysm. These findings preliminarily revealed the influence of lower limb amputation on the occurrence of cardiovascular diseases, and provided theoretical guidance for the design of rehabilitation training and the optimization of cardiovascular diseases treatment.
Objective To observe the effect of ophthalmotonus intervention on ocular hemodynamics in patients with ischemic ophthalmopathy (IOP). Methods 106 IOP patients (106 eyes) were enrolled in this study, including 74 eyes with nonarteritic anterior ischemic optic neuropathy (NAION), 20 eyes with retinal artery occlusion (RAO) and 12 eyes with ocular ischemia syndrome (IOS). The patients were randomly divided into ophthalmotonus intervention group and control group. There were 37 NAION eyes, 10 RAO eyes and six IOS eyes in each group. The patients of ophthalmotonus intervention group received lowering intraocular pressure treatment in addition to the basic therapy to reduce the intraocular pressure to le;12 mm Hg (1 mm Hg=0.133 kPa) or decreased by 7-8 mm Hg, or in a 20%-30% reduction. The patients of control group avoided lowering intraocular pressure treatment. The arm-retinal circulation time (A-RCT) and the peak systolic velocity (PSV), end diastolic velocity (EDV) and resistance index (RI) of ophthalmic artery (OA), central retinal artery (CRA) and short posterior ciliary arteries (PCA) before and one week after treatment were comparatively analyzed by fluorescence fundus angiography (FFA) and color Doppler flow imaging. Results The differences of A-RCT before treatment in ophthalmotonus intervention group and control group in NAION, RAO and IOS patients were not statistically significant (t=0.869, 0.119, 0.000; P＞0.05). The differences of PSV (OA:t=0.586, 0.040, 0.067; CRA:t=0.285, 0.057, 0.775; PCA:t=0.658, 0.653, 1.253), EDV (OA:t=0.274, 0.080, 0.093; CRA:t=0.781, 0.077, 0.277; PCA:t=0.200, 0.209, 0.299) and RI (OA:t=0.121, 0.153, 0.138; CRA:t=0.172, 0.242, 0.642; PCA:t=1.053, 1.066, 0.266) of OA, CRA and PCA before treatment in ophthalmotonus intervention group and control group were not statistically significant (P＞0.05). Compared with control group, A-RCT shortened obviously (t=2.573, 2.236, 2.607; P＜0.05) in ophthalmotonus intervention group one week after treatment. Compared with control group, PSV (OA:t=2.367, 2.368, 2.267; CRA:t=0.775, 1.927, 2.775; PCA:t=2.253, 2.353, 2.353) and EDV (OA:t=2.303, 2.236, 2.503; CRA: t=2.277, 2.377, 2.577; PCA:t=2.299, 2.399, 2.299) of OA, CRA and PCA increased obviously (P＜0.05), RI of OA, CRA and PCA decreased obviously (OA:t=2.238, 2.387, 2.228; CRA:t=2.342, 2.442, 2.542; PCA:t=2.266, 2.366, 2.266; P＜0.05) one week after treatment in treatment group. Conclusion Ophthalmotonus intervention can improve the ocular hemodynamics in IOP patients.
目的 分析彩色多普勒超声对肝硬化患者门静脉血流改变的评价作用。 方法 选择2010年1月－2011年4月收治的50例肝硬化患者作为观察组，其中代偿期患者27例，失代偿期患者23例；同时设置健康对照组50名，比较两组的门静脉内径（Dpv）、门静脉平均血流速度（Vpv）、门静脉血流量（Qpv）。 结果 观察组患者的Dpv增宽，Vpv减慢，Qpv减少，与对照组比较，差异均有统计学意义（P＜0.05）；且失代偿期患者的改变更为明显，与代偿期患者间差异有统计学意义（P＜0.05）。 结论 彩色多普勒超声检查门静脉血流改变可以对肝硬化患者进行初步确诊。