体外循环对脑电图双频和听觉诱发电位指数的影响

The effect of cardiopulmonary bypass on bispectral index and auditory evoked potentials

目的 探讨体外循环 (CPB)非搏动性血流灌注、流量、灌注压、温度、低温停循环和脑缺血再灌注对脑电图(EEG)双频指数 (bispectralindexBIS) ,听觉诱发电位指数 (auditoryevokedpotentialsAEP)的影响。 方法 2 0例低温停循环患者分为Ⅰ组高流量和Ⅱ组低流量。每组设麻醉前、麻醉后等 15个观测点。在平稳的麻醉状态下观察CPB非搏动性灌注、流量、灌注压、温度和低温停循环对BIS、AEP的影响。结果 体外转流时、主动脉阻断时BIS、AEP明显下降 (p<0 .0 5 )。低温停循环时BIS、AEF显著下降 (p<0 .0 1)。恢复循环后显著上升 (p<0 .0 1)。心脏复跳后 ,体外停机后BIS、AEP明显上升 (p <0 .0 5 )。结论 CPB非搏动性血流灌注对脑电活动和意识有明显的抑制。CPB低流量、低灌注压、低温均对BIS和AEP有明显的抑制。

OBJECTIVE To analysis the effects of non-pulsating perfusion, flow, blood pressure(BP), temperature(T), hypothermia with circulatory arrest(HCA) and cerebral ischemia and reperfusion on bispectral index(BIS) and auditory evoked potentials(AEP).METHODS 20 cased were divided into two groups randomly: I group(high flow) and II group(low flow). During the stable state of anesthesia, BIS and AEP were recorded at 15 different times. Non-pulsating perfusion, flow, BP, T and hypothermia with circulatory arrest were also recorded simultaneously. RESULTS During cardiopulmonary bypass(CPB), BIS and AEP decreased markedly after aorta occlusion (p<0.05)and in hypothermia with circulatory arrest (p<0.01). BIS and AEP increased markedly after the recovery of circulation(p<0.01)and after return of heart beat and the stop of CPB(p<0.05).CONCLUSIONS Non-pulsating perfusion in CPB can markedly depressed the activity of cerebral electricity and consciousness. During CPB, low flow, hypotension, hypothermia can markedly depressed BIS and AEP. Hypothermia with circulatory arrest can induce δ waves of cerebral ischemia-reperfusion.