【作者】 张宏鹏；

【导师】 郭伟；

【作者基本信息】 中国人民解放军军医进修学院 ， 外科学， 2007， 硕士

【摘要】 目的：建立多参数脊髓缺血监测和评价系统，利用支架型血管制作胸主动脉EVR模型，探讨术中不同血压对截瘫并发症的影响。方法：(1)造影测量犬胸主动脉的长度和近远端的内径，根据结果设计制造支架型血管，并利用改造的输送器，以髂动脉为入路，将支架型血管释放于胸主动脉；(2)将20只犬随机分为高血压组、低血压组、正常血压组和空白对照组；(3)分别在术前、术后15、30、60、90分钟进行SEP，脑脊液和动脉血的PH值、pCO2、葡萄糖、乳酸、NSE定量检验，术后24、48、72小时分别进行神经系统评分，术后1个月处死后行脊髓病理观察；(4)将实验数据进行统计学分析(p＜0.05)。结果：(1)适合体重为23-25kg成年家犬胸主动脉使用的支架型血管的平均型号为近端直径20mm，远端直径12mm，长度250mm，髂动脉能够容纳的输送器的最大外径为18F。(2)各手术组，脑脊液中的乳酸含量术后均多于术前，同一时间不同实验组乳酸含量无统计学差异。(3)各实验组，脑脊液中的葡萄糖含量术后与术前无统计学差异，同一时间不同实验组葡萄糖含量无统计学差异。(4)各手术组，脑脊液中的NSE含量术后60、90分钟多于术前。术后30分钟，低血压组含量多于正常血压组；术后60、90分钟，高血压组含量少于低血压组，而高血压组和正常血压组以及正常血压组和低血压组间无统计学差异。(5)各手术组，脑脊液中的pCO2值术后60、90分钟高于术前。术后60、90分钟，高血压组的值低于低血压组。术后60分钟，正常血压组的值低于低血压组。(6)高血压组术后60分钟脑脊液中的PH值低于术前。同一时间不同实验组间无统计学差异。(7)神经系统评分：各组内不同时间无统计学差异；术后24小时，低血压组与空白对照组有统计学差异。(8)诱发电位结果：高血压组内除术后15分钟，均与术前有统计学差异；正常血压组和低血压组内术后均与术前有统计学差异。同一时间段不同实验组间均有统计学差异，波幅峰值空白对照组＞高血压组＞正常血压组＞低血压组，潜伏期空白对照组＜高血压组＜正常血压组＜低血压组。(9)病理检查结果：各手术组脊髓出现不同程度的缺血坏死。高血压组与低血压组和正常血压组有统计学差异。结论：脑脊液中乳酸和NSE的升高以及pCO2值的下降表示脊髓发生缺血，而葡萄糖、PH值对脊髓缺血不敏感；pCO2值和NSE对机体血压变化引起的脊髓血供改变敏感，但乳酸不敏感。SEP对脊髓缺血非常敏感，机体血压变化会引起SEP的相应改变；病理结果符合SEP的变化趋势。综合各指标得出结论，胸主动脉腔内修复术中高血压对脊髓血供有保护作用，低血压可加重脊髓缺血损伤。更多还原

【Abstract】 Objective: Set up a multi-factors system for monitoring and evaluating spinal cord ischemia and make a canine EVR model with stent-graft. Probe the effect of blood pressure on paraplegia during endovascular TA repair with the model.Methods: (1) To design and manufacture the stent-grafts which are fit for the ascending aorta in canine through measuring the radiography result. Using a special delivery, we release the stent-graft to TA from iliac artery. (2) 20 canines were used, which were randomly divided into group A (Hypertension), B (Hypotension), C (Normal) and D (Vacant control group). (3) Arterial blood and CSF samples were carried out to determine PH, pCO2, glucose, lactate and NSE at preoperation and postoperation 15, 30, 60 and 90 mins. SEP was measured at the same intervals. All animals were evaluated neurologically at postoperation 24, 48 and 72 hours. At last canines were sacrificed for spinal cord pathologic assessment at postoperation 1 month. (4) Statistical analysis (p ≤ 0.05).Results:(1) The average size of stent-graft fitting for 23-25kg dogs are that proximal diameter is 20mm, distal diameter is 12mm, length is 250mm. The biggest diameter is 18F that could pass through the iliac artery.(2) In operation groups, the level of lactate in CSF at postoperation is higher than preoperation. And in different groups p > 0.05 at the same time.(3) In all groups, the level of glucose in CSF has no singnificantly difference which is similar with in multigroups at same time.(4) In operation groups, the level of NSE in CSF at postoperation 60, 90 mins are higher than preoperation. At 30mins, NSE in B group is more than in C group. At 60, 90 mins, NSE in A group is less than B. However, between A and C groupp > 0.05 similar with C and B group.(5) In operation groups, the level of pCO2 in CSF at postoperation 60, 90 mins are higher than preoperation. At 60, 90mins, pCO2 in A group is less than in B group. At 60mins, pCO2 in C group is less than B.(6) In A group, the level of pCO2 in CSF 60 mins is lower than preoperation. In different groups p > 0.05 at the same time.(7) Neurologic assessment: In every group, p > 0.05 at different times. At 24 hours, there is singnificantly difference between B and D group.(8) SEP: In operation groups, there are singnificantly differences at different times similar. At same time, between different groups there are singnificantly differences: the ratio of amplitude is D > A > C> B, the incubation period is D < A<C<B.(9) Pathologic assessment: In operation groups, the spinal cord have different degree cellular necrosis. There is singnificantly difference between B and A similar with A and C.Conclusions: Increased levels of lactate and NSE as well as decreasing level of pCO2 in CSF predict spinal ischemia, but the change of glucose and PH in CSF isn’t sensitive to spinal ischemia. SEP seems to be a useful and efficient monitoring that could forcast spinal ischemia and effect of different blood pressure on the risk of paraplegia which is similar with pCO2 and NSE in CSF, yet lactate isn’t a good predictor to blood pressure. Pathology results are consistent with SEP outcome. From our observation we conclude that during endovascular thoracic aorta repair hypertension can lower the risk of paraplegia, however hypotension worsen spinal ischemia injury.更多还原