异丙酚对定量药物脑电图δ频段影响的量效与时效关系

目的通过观察异丙酚对兔翻正反射的影响和定量药物脑电图(QPEEG)的变化,探讨异丙酚对 QPEEG δ频段影响的量效关系和时效关系.方法选用健康成年白色家兔18只,雌雄兼用,随机分为 3组,每组 6只.应用 QPEEG,采用功率谱分析法,分析兔静注异丙酚前后脑电活动的变化.结果异丙酚2.5 mg/kg对δ频段的功率百分比无明显影响; 5 mg/kg使δ频段的功率百分比增大1倍以上,但差异没有显著性意义( P >0.05); 10 mg/kg使各脑区δ频段功率百分比在20 s～ 5 min内均显著增大( r=0.68,0.84,0.93,0.94,P < 0.01, P < 0.05)且与行为变化平行.δ频段的改变与异丙酚剂量在5min内均呈显著正相关( r = 0.62～ 0.95,P < 0.01).结论异丙酚以剂量依赖方式增大兔QPEEGδ频段的功率百分比,提示δ频段可在一程度上成为反映催眠作用的深度及镇痛程度的指标.

Dose-effect and time-effect of propofol on δ-band of quantitative pharmaco-EEG

Aim The study is to investigate the effects of propofol on δ-band of quantitative pharmaco-electroencephalography(QPEEG) in the rabbits, determination of dose-effect and time-effect relationships.Methods One dose of propofol was injected to the rabbits.The EEG samples were obtained prior to and at regular intervals following the injection of propofol.The EEG activity was processed with the power spectral analysis.Results The percentage of δ-band power showed no significant changes in group of 2.5 mg/kg; The percentage of δ-band power were increased 1 folds higher, but did not reach significant level(P >0.05) in group 5 mg/kg.However, the changes in group 10 mg/kg was significant (r=0.68,0.84,0.93,0.94,P< 0.01,P< 0.05), and moreover it has parallelism with behavior alteration of the rabbit from 20 s to 5 min.A positive correlation of δ-band power and propofol dose was detected during 5 min(r=0.62- 0.95, P< 0.01).Couclusion With the increase of propofol dose,the percentage of power progressively increased at δ-band, it is suggested that the percentage of power at δ-band would be a effective mean of monitoring anesthesia depth.