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 observe ocular ischemic appearance (OIA) associated with carotid artery stenosis and its effects on the hemodynamics of central retinal artery (CRA) and ophthalmic artery (OA). MethodsA total of 30 normal persons and 60 patients with carotid artery stenosis diagnosed by color Doppler flow imaging (CDFI) and digital subtraction angiography (DSA) were enrolled in this prospective study.Sixty patients were randomly divided into 2 groups:30 patients with the carotid artery stenosis degree < 60% and 30 cases with the carotid artery stenosis degree≥60%. Thirty normal persons were enrolled in the normal control group. All patients underwent a comprehensive eye examination to determine if OIA exists. The Doppler spectral patterns of CRA and OA were observed by CDFI. The peak systolic velocity (PSV), end diastolic velocity (EDV), blood vessel diameter (BVD) and resistance index (RI) of CRA and OA were measured. ResultsIn the group of the carotid artery stenosis degree≥60%, 24/30 patients (80.0%) had the ophthalmic symptoms and 9/30 patients (30.0%) had ophthalmic signs. In the group of the carotid artery stenosis degree < 60%, 9/30 patients (30.0%) had the ophthalmic symptoms and 3/30 patients (10.0%) had ophthalmic signs. For patients with≥60% stenosis, CDFI revealed a bread-like waveform of CRA, and single peak of OA instead of the typical 3-peak/2-notch waveform. For patients with < 60% stenosis, CDFI revealed a normal pattern of CRA and OA (3-peak/2-notch). The PSV(t=5.255, P=0.007) and EDV(t=4.949, P=0.005) of CRA in the stenosis≥60% group were statistically decreased compared to the normal control group, but the BVD(t=0.457, P > 0.05)and RI(t=0.213, P > 0.05)were normal. The PSV, EDV, BVD and RI of CRA in the stenosis < 60% group were normal(P > 0.05). The PSV(t=4.457, P=0.010)and EDV(t=4.588, P=0.009)of CRA in the stenosis≥60% group were statistically decreased compared to the stenosis < 60% group, but the BVD and RI were the same between these 2 groups. ConclusionPatients with carotid stenosis≥60% had a higher OIA incidence, reduced PSV, EDV of their CRA, while had no significant changes of OA hemodynamics.
目的:观察等效剂量瑞芬太尼和芬太尼诱导气管插管对小儿血流动力学的影响。方法:40例择期行全麻患儿随机分为瑞芬太尼组和芬太尼组,麻醉诱导使用咪唑安定0.15mg/kg、丙泊酚2.5mg/kg、芬太尼2.5μg/kg或瑞芬太尼2μg/kg和维库溴铵0.1mg/kg。分别于麻醉诱导前(T0)、诱导后2min(T1)、插管后1、2min(T2、T3)记录心率、收缩压和舒张压。结果:两组诱导前血流动力学指标相似。与T0时比较,两组患儿T1时收缩压、舒张压均降低(Plt;0.05或Plt;0.01),心率均减慢(Plt;0.05或Plt;0.01);瑞芬太尼组T2.T3时收缩压、舒张压降低(Plt;0.05或Plt;0.01),心率减慢(Plt;0.05);芬太尼组T2、T3时收缩压、舒张压升高(Plt;0.05),心率增快(Plt;0.05)。与芬太尼组比较,瑞芬太尼组T1、T2和T3时收缩压、舒张压均降低(Plt;0.05),心率减慢(Plt;0.05)。结论:瑞芬太尼比等效剂量芬太尼能更好地抑制小儿全麻诱导气管插管时的心血管反应。
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.
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.
Hemodynamics plays a vital role in the development and progression of cardiovascular diseases, and is closely associated with changes in morphology and function. Reliable detection of hemodynamic changes is essential to improve treatment strategies and enhance patient prognosis. The combination of computational fluid dynamics with cardiovascular imaging technology has extended the accessibility of hemodynamics. This review provides a comprehensive summary of recent developments in the application of computational fluid dynamics for cardiovascular hemodynamic assessment and a succinct discussion for potential future development.
ObjectiveTo investigate impact of splenectomy plus pericardial devascularization on liver hemodynamics and liver function for liver cirrhosis patients with portal hypertension. MethodsThe internal diameter, maximum velocity, minimum velocity, mean velocity, and flow volume of portal vein and hepatic artery of 42 cases of liver cirrhosis with portal hypertension were measured by Doppler ultrasonic instrument on day 1 before operation and on day 7 after operation. The free portal pressures at different phases (after open abdomen, after splenic artery ligation, after splenectomy, and after devasculanrization) were read from the disposable pressure sensor. Twenty-four healthy people through physical examination were selected as control. Results① The free portal pressure of liver cirrhosis patients with portal hypertension was decreased from (29.12±1.40) mm Hg after open abdomen to (22.71±1.21) mm Hg after splenic artery ligation, and further decreased to (21.32±1.12) mm Hg after splenectomy, but increased to (22.42±1.15) mm Hg after devasculanrization, the difference was statisticly different (all P < 0.01). ② Compared with the healthy people, for the liver cirrhosis patients with portal hypertension, the internal diameter, maximum velocity, minimum velocity, and flow volume of portal vein were significantly enlarged (all P < 0.01), which of hepatic artery were significantly reduced (all P < 0.01) on day 1 before operation; On day 7 after operation, the internal diameter of portal vein was significantly reduced (P < 0.01), the maximum velocity, minimum velocity, and mean velocity of portal vein were significantly enlarged (all P < 0.01), but the internal diameter of hepatic artery was significantly reduced (P < 0.01), the maximum velocity, minimum velocity, mean velocity, and flow volume of hepatic artery were significantly enlarged (all P < 0.01). For the liver cirrhosis patients with portal hypertension, compared with the values on day 1 before operation, the internal diameter and the flow volume of portal vein were significantly reduced (all P < 0.01) on day 7 after operation; the internal diameter, maximum velocity, minimum velocity, mean velocity, and flow volume of hepatic artery were significantly enlarged (all P < 0.01) on day 7 after operation. ③ The Child-Pugh classification of liver function between before and after surgery had no significant difference (χ2=1.050, P > 0.05). ④ No death and no hepatic encephalopathy occurred, no thrombosis of splenic vein or portal vein was observed on day 7 after surgery. Conclusionsplenectomy plus pericardial devascularization could decrease portal vein pressure and reduce blood flow of portal vein, while increase blood flow of hepatic artery, it doesn't affect liver function.
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。
目的 评价舒芬太尼复合艾司洛尔对腹腔镜胆囊切除术二氧化碳气腹期间心血管反应和脑电双频指数（BIS）的影响。 方法 2010年1月－2011年12月间，选择美国麻醉医师协会分级Ⅰ～Ⅱ级择期腹腔镜胆囊切除术患者90例，随机分为芬太尼组（A组）、舒芬太尼组(B组）和舒芬太尼+艾司洛尔组（C组）。A组用芬太尼4 μg/kg，B、C组用舒芬太尼0.6 μg/kg麻醉诱导后气管插管，机械通气；C组在气腹前加用艾司洛尔。3组均常规静脉注射咪达唑仑0.1 mg/kg、丙泊酚2 mg/kg和维库溴铵0.1 mg/kg。分别记录各组在气腹前（T1）、气腹30 s（T2）、气腹5 min（T3）、气腹15 min（T4）时的收缩压、舒张压、平均动脉压、心率、血氧饱和度和BIS值。 结果 T1时C组收缩压、舒张压、心率、BIS值最低，各组间差异无统计学意义（P＞0.05）；T2、T3、T4时A组收缩压、舒张压、心率、BIS明显增加，B组有所上升，ⅢC组各时段变化不明显。A组与B组、B组与C组间差异有统计学意义（P＜0.05）。 结论 舒芬太尼复合艾司洛尔能更好地预防腹腔镜胆囊切除术二氧化碳气腹期间心血管反应和抑制BIS的增加。
Objective To introduce the clinical significance and pathophysiologic aspects of the circulatory and cardiac complications in terminal stage cirrhosis. Methods Recently relevant literatures were reviewed and summarized. Results Haemodynamic changes in cirrhosis arose on the basis of combined humoral and nervous dysregulation, with abnormalities in cardiovascular regulation, volume distribution and cardiac performance. Conclusion Comprehending the mechanisms of cardiovascular complications will contribute a lot for the treatment of terminal stage cirrhosis.