上胸段硬膜外阻滞与尼莫地平减轻兔脑血管痉挛作用的比较

目的比较上胸段硬膜外阻滞（HTEB）减轻兔蛛网膜下腔出血（SAH）后脑血管痉挛（CVS）的作用是否优于尼莫地平。方法切开置管法制备HTEB模型的新西兰兔60只,按随机数字表法随机分成4组（n=15）：假手术组、对照组）、HTEB治疗组和尼莫地平治疗组。＂枕大池二次注血法＂（0.5ml/kg）制成兔SAH模型,1、7和14d后用经颅多普勒检测基底动脉平均血流速度（Vm）。处死后取基底动脉,光镜下观察其形态学变化。结果与假手术组相比,对照组、HTEB治疗组和尼莫地平组的基底动脉Vm均明显升高（P〈0.01）;但HTEB治疗组和尼莫地平组的基底动脉Vm明显低于对照组（P〈0.05）,而两治疗组差异无统计学意义（P〉0.05）。光镜下,对照组基底动脉管壁增厚、管腔变窄;两治疗组管壁增厚不明显,管腔仍有狭小,较对照组明显改善;两治疗组之间血管壁变化无明显差异。结论 HTEB减轻兔SAH后CVS的程度与尼莫地平相当。

Comparison of preventive effect of high thoracic epidural block on cerebral vasospasm with that of nimodipine in the rabbits

Objective To compare the preventive effects of high thoracic epidural block （HTEB） on cerebral vasospasm （CVS） following subarachnoid hemorrhage （SAH） with that of nimodipine in rabbits. Methods HTEB at T6~7 epidural space was performed in 60 rabbits, who were randomly divided into 4 groups of 15 rabbits each, i. e. the sham-operation group, control group, HTEB treatment group, nimodipine treatment group. SAH was developed by two injection of autoblood into the cistern magna （0.5 ml/kg）. Transcranial Doppler ultrasonography was used to detect the basilar artery mean flow velocity （Vm） 1, 7 and 14 days after SAH. The changes in histological morphology of the basilar artery were observed under a light Microscope. Results The Vm of the basilar artery in the control group and two treatment groups was significantly faster than that in the sham operation group （P〈0.01）; The Vm of the basilar artery in the control group was significantly faster than that in both the treatment groups （P〈0.05）; There were insignificant difference in the Vm of the basilar artery between both the treatment groups （P〉0.05）. Pathological observations showed that in the control group the lumina of the basilar arteries was narrower and the basilar artery walls were thicker than those in the two treatment groups, but there were no significant difference in the walls thickness and the lumens sizs of the basilar arteries between the two treatment groups. Conclusion Continuous HTEB is similar to nimodipine in preventive effect on SAH-associated CVS in rabbits.