脑电非线性分析在麻醉深度监测中的应用

Application of EEG non-linear analysis in monitoring depth of anesthesia

目的 探讨全身麻醉 (全麻)过程中脑电非线性动力学特性的变化规律 ,并应用非线性指数实时监测全麻过程。方法 6 5名手术患者随机分为异氟醚组、七氟醚组、地氟醚组(每组 15例 )、静脉全凭异丙酚 8mg/ (kg·h)组和 10mg/ (kg·h)组 (每组 10例 ) ,对所有患者全麻过程进行了全程脑电监测 ,包括入室、诱导、手术中、复苏、觉醒过程 ,并利用关联维数(D2 )和近似熵 (ApEn)非线性指数进行了麻醉过程的实时监测。结果 非线性指数在入室清醒状态最高 ,诱导过程中迅速降低 ,手术中保持低水平、相对稳定的数值 ,以后随复苏过程逐渐升高 ,最后在觉醒时恢复较高水平。其中D2 非线性指数分别为 4 99、4 14、3 4 2、3 99、4 5 6 ,ApEn非线性指数分别为 0 83、0 6 9、0 5 4、0 6 3、0 74。结论 非线性指数能够实时监测全麻过程脑电活动的变化 ,准确反映麻醉深度的变化情况。脑电非线性动力学分析能够提供更多有关意识层次的信息。

Objective To investigate the changes in non-linear dynamics properties of EEG and the application of real-time monitoring of non-linear indexes during the course of general anesthesia. Methods EEG was recorded in 65 patients undergoing operations. They were randomly divided into five groups: isoflurane, sevoflurane, desflurane (n=15, respectively), propofol 8mg/(kg·h) and propofol 10mg/(kg·h) (n=10, respectively). The EEG derived parameters correlation dimension (D 2 ) and approximate entropy (ApEn) non-linear indexes were calculated simultaneously during the whole operation, including the time of entering the operation room, anesthetic induction, intraoperation, recovery, and regaining consciousness. Results At the time of entering the operation room, their D 2 and ApEn nonlinear indexes appeared to be highest. Both the indexes decreased swiftly during anesthetic induction, and they dropped to lower values and leveled off during the intra-operation period. During recovery period, both of them rose gradually and returned to a high level in the post-operation awaking period. Conclusions Changes in the depth of anesthesia could be real-timely monitored and precisely measured with non-linear indexes of EEG. Non-linear dynamic analysis might provide us with more information on consciousness during general anesthesia