心率变异性近似熵分析法与脑电双频谱指数间的相关性

目的:观察全身麻醉时心率变异性分析中近似熵分析法与脑电双频谱指数(BIS)在监测麻醉深度时的相关性。方法:对40例全身麻醉病人测定麻醉前(T1)、诱导插管(T2)、术中(T3)、苏醒(T4)4个时间点各5min的心率(HR)、平均动脉压(MAP)、脑电双频谱指数(BIS)和近似熵(ApEn)变化。结果:HR在T2、T3和T4均较T1值升高(P0.01～0.05)。MAP在T2时较T1值降低(P0.05),T3、T4较T1值升高(P0.05),而T4比T3明显升高(P0.01)。BIS值在麻醉后各时点均较T1值下降明显(P0.01),其中T4也较T1下降(P0.05),T3与T2时相比明显降低(P0.01),而T4较T3明显升高(P0.01)。近似熵值的T1值均大于其他各时点(P0.01～0.05),其T4较T3时点升高(P0.01),T3较T2时点降低(P0.05)。结论:作为心率变异性的非线性分析方法指标的近似熵分析法,能描述围术期心脏自主神经功能状态的变化,但其与BIS并无相关性。

Correlation between Monitoring Parameters of Approximate Entropy of Heart Rate Variability and BIS during General Anesthesia

Objective To compare the changes of approximate entropy and bispectral index（BIS） during general anesthesia, and to estimate the relationship between approximate entropy and bispectral index.Methods Parameters as heart rate（HR） mean arterial pressure（MAP） BIS and approximate entropy were monitored and recorded before induction T1）, induction and intubation（T2）, operating 1h（T3） and regain consciousness（T4） of forty patients of ASA 1～II with general anesthesia.Results Compared to T1, the HR was increased at the other time-points.The value of MBP at T2 was lower than that at T1, and at T3 and T4 were higher than that at T1, but the value of T3 was significantly different from that of T4.Compared to T1 the value of BIS at the other time-point was decreased and that at T4 was lower than that at T1,.That at T3 was significantly lower than that at T2, but that at T4 was higher than that at T3.the value of approximate entropy at T1 was higher than at the other time-points and that at T4 was higher than those at T2 and T3, but compared to that at T2 that at T3 was higher.But approximate entropy and BIS had no correlation.Conclusion As the parameter of the nonlinear analysis of heart rate variability, the approximate entropy can describe the changes of the autonomic nerve system functional status, but with no relationship to BIS.