Brain protection during antegrade selective cerebral perfusion in patients with old cerebral infarction.

目的：探讨反应性自由基与脑梗死患者顺行选择性脑灌注（ASCP）术后神经功能障碍的关系。我们在犬模型中评估了预防性给药依达拉奉（一种自由基清除剂）对伴有或不伴有老年性梗死脑ASCP的脑保护作用。方法：采用脑中动脉注射圆柱形硅胶栓子建立犬老年性脑梗死模型。有明显神经功能缺损且存活4周及以上的动物加入模型。对完整动物（非依达拉奉组，A组，依达拉奉治疗组，B组）和梗死动物（非依达拉奉组，C组，依达拉奉治疗组，D组）进行深度低温伴ASCP。术中测定血清丙二醛（MDA）、己烯醛-赖氨酸（HEL）、谷氨酸、静脉-动脉乳酸差（VALD）浓度，评估中枢传导时间（CCT）和体感诱发电位振幅。结果：与对照组相比，C组大鼠血清MDA和HEL浓度在ASCP结束时显著升高，谷氨酸在复温期显著升高。d组均抑制了上述生化指标的升高。C组28℃复温期VALD显著高于对照组。C组术后CCT明显延长，神经元活性明显降低，d组均恢复正常。结论：预防依达拉奉对陈旧性脑梗死犬ASCP术后神经功能障碍有显著保护作用。

Objective : Reactive free radical species are thought to be involved in postoperative neurological dysfunction after antegrade selective cerebral perfusion (ASCP) in brain with old infarction. We assessed the brain protective effect of prophylactically administered edaravone, a free radical scavenger, for ASCP in brains with or without old infarction in a canine model.Methods : Canine model of old cerebral infarction was created by injecting cylindrical silicone embolus into the middle cerebral artery. Animals showing obvious neurologic deficits and surviving 4 weeks or longer were included in the model. Deep hypothermia with ASCP was performed in both intact (non-edaravone; group A, edaravone-treated; group B) and infarcted animals (non-edaravone; group C, edaravone-treated; group D). Serum concentrations of malondialdehyde (MDA), hexanoyle-lysine (HEL), glutamate, and venous-arterial lactate difference (VALD) were measured and central conduction time (CCT) and amplitude of somatosensory evoked potentials were assessed during the operation.Results : Compared with the intact groups, serum concentrations of MDA and HEL in group C significantly increased at the end of ASCP, while that of glutamate did so in the rewarming phase. Increase in all these biochemical parameters were suppressed in group D. In group C, VALD was significantly greater in the rewarming phase at 28℃ compared with intact groups. Significant prolongation of post operative CCT and decrease in neuronal activity were detected in group C, both of which recovered in group D.Conclusion : Prophylactic administration of edaravone exerted a significant protective effect against postoperative neurological dysfunction after ASCP in a canine model with old cerebral infarction.