腰池持续引流防治蛛网膜下腔出血后脑血管痉挛的作用机制

目的　研究腰池持续引流对蛛网膜下腔出血 (SAH)后脑血管痉挛 (CVS)的防治作用 ,并进一步探讨引流的作用机制。方法　经皮枕大池 2次注血法建立犬SAH动物模型 ,设立引流组和对照组 ,引流组于第 2次注血后即开始腰椎蛛网膜下腔置管持续引流血性脑脊液 ,动态测定两组脑脊液中红细胞 (RBC)、内皮素 1(ET 1)和一氧化氮 (NO)含量 ,脑血管造影确定脑血管痉挛程度 (%reductionofbasilararterydiamiter,%RBAD)。对两组CVS的影像学结果及脑脊液中RBC、ET 1和NO含量进行对比分析。结果　SAH后引流组CVS例数少 ,痉挛程度轻。引流组脑脊液中红细胞清除速率快 ,ET 1含量显著低于对照组 ,NO含量显著高于对照组。结论　SAH后腰池持续引流通过清除蛛网膜下腔致痉挛物质 ,改变脑脊液中ET 1和NO的含量 ,可以预防和缓解血管痉挛。

Effect and mechanism of lumbar subarachnoid space continuous drainage on cerebral vasospasm prevention and treatment following experimental subarachnoid hemorrhage

Objective To investigate the effect of lumbar subarachnoid space continuous drainage on cerebral vasospasm(CVS) prevention and treatment following experimental subarachnoid hemorrhage(SAH), and further explore the mechanism of CVS prevention and treatment.Methods An experimental SAH was achieved by twice injections of fresh autologous arterial blood into cisterna magna of each dog. The dogs were randomly divided into drainage group and control group and it was just after the second injection of fresh blood that the drainage group began to drain blood cerebral spinal fluid(CSF).The contents of red blood cell(RBC), endothelin-1(ET-1) and nitric oxygen(NO) in CSF were measured respectively. The degree of CVS was analyzed through angiography (%reduction of basilar artery diamiter,%RBAD). The angiographic results of CVS were analyzed and the changes of RBC, ET-1 and NO in CSF at different stages were compared between two groups. Results The drainage group had fewer cases of CVS and the severity of CVS was more slight compared with control group.Drainage group had a significantly higher cleaning rate of RBC.In drainage group,the content of ET-1 was lower and the content of NO was higher significantly than control group.Conclusions Through cleaning the vasogenic substances in subarachnoid space,lumbar subarachnoid space continuous drainage can change the levels of ET-1 and NO in CSF and may prevent and reverse CVS following.