颅脑损伤患者丙泊酚靶控浓度与脑电双频指数变化的关系

目的观察丙泊酚诱导过程中,轻中度颅脑损伤患者的效应室浓度与脑电双频指数(BIS)变化的关系。方法选择颅脑损伤后GCS评分为9～15分,拟行急诊开颅手术的患者19例。所有患者入室后行BIS及心电图、上臂血压、血氧饱和度(SpO2)监测,以丙泊酚靶控输注进行诱导,靶控效应室浓度从0.5μg/ml开始,当效应室达到设定浓度后增加0.5μg/ml,直到3.5μg/ml,记录基础值及每个浓度稳定时的BIS值、心率(HR)及平均动脉压(MAP)。结果效应室靶控浓度与BIS呈直线负相关(r=-0.63,P<0.01),回归方程:BIS值=81.2-11.47×丙泊酚效应室靶控浓度。效应室靶控浓度达到3.5μg/ml时,MAP降幅达到基础值的34.7%。结论丙泊酚效应室靶控浓度与BIS呈负相关,可用于评估镇静深度。当效应室靶控浓度>3μg/ml,对轻中度颅脑损伤的MAP影响较大。

The relationship between targeting effect compartment concentration of propofol and the fluctuation of bispectral index in patients with brain injuries

Objective To investigate the relationship between the target effect compartment site concentration of propofol and the changes of bispectral index(BIS) during propofol induction for patients with mild and moderate brain injuries.Methods 19 patients with brain injuries(GCS 9～15) and planned for emergency craniotomy were enrolled in this study.The monitoring of BIS,ECG,blood pressure and SpO2 for all patients after entering the operation room were performed.Target-controlled infusion of propofol for induction and the target effect compartment site concentration of propofol started with 0.5μg/ml,when the target effect compartment concentration of propofol reached to the predicted plasma propofol concentration,the latter was increased by 0.5μg/ml until the former reached to 3.5μg/ml.Recorded the baseline values and the BIS values,HR and MAP at each stable concentration.Results The target effect-site concentration of propofol is adversely associated with BIS(r=-0.63,P<0.01,regression equation:BIS=81.2-11.47×target effect-site concentration of propofol.Basic MAP reached to a decrease of 34.7% when target effect-site concentration of propofol was up to 3.5μg/ml.Conclusion The target effect-site concentration of propofol is adversely associated with BIS which can be used as markers to evaluate the depth of sedation.It will be greatly impacted on the MAP of the mild and moderate brain injuries when target effect-site concentration of propofol was over 3μg/ml.