人工流产术患者复合异丙酚时靶控输注瑞芬太尼的药效学

目的 探讨人工流产术患者复合异丙酚4.5 μg/ml时靶控输注瑞芬太尼的药效学.方法 拟行人工流产术患者135例,年龄18～30岁,ASAI级,孕6～10周.随机分为9组(n=15):瑞芬太尼效应室靶浓度分别为0.5、0.8、1.1、1.4、1.7、2.0、2.3、2.6和2.9 ng/ml(Ⅰ组～Ⅸ组).各组异丙酚效应室靶浓度均为4.5 μg/ml.采用概率单位回归分析法,计算麻醉效果达优时瑞芬太尼效应室靶浓度EC50、EC95及其95%可信区间(CI)和呼吸抑制时瑞芬太尼效应室靶浓度EC50、EC95及其95%CI.结果 麻醉效果达优时瑞芬太尼的效应室靶浓度EC50为1.67 ng/ml,其95%CI为1.45～1.90 ng/ml,EC95为3.88 ng/ml,其95%CI为3.08～5.89 ng/ml;呼吸抑制时瑞芬太尼效应室靶浓度EC50为2.44 ng/ml,其95%CI为2.28～2.64 ng/ml,EC95为3.36 ng/ml,其95%CI为2.99～4.34 ng/ml.麻醉效果达优时瑞芬太尼的效应室靶浓度EC95高于呼吸抑制时效应室靶浓度EC95(P＜0.05).结论 人工流产术患者复合异丙酚4.5 μg/ml时,麻醉效果达优时瑞芬太尼的效应室靶浓度EC50、EC95,分别为1.67、3.88 ng/ml,呼吸抑制时瑞芬太尼的效应室靶浓度EC50、EC95,分别为2.44、3.36 ng/ml.

Pharmacodynamics of remifentanil by TCI used in combination with propofol for dilatation and curettage

Objective To determine the effective effect-site concentration and respiratory depression effect-site concentration of remifentanil used in combination with propofol for dilatation and curettage(D&C).Methods One-hundred and thirty-five ASA Ⅰ 6-10 wk pregnant nulliparae aged 18-30 yr undergoing D&C were randomly allocated into 9 groups based on the initial effect-site concentration of remifentanil administered by TCI (n=15 each):0.5,0.8,1.1,1.4,1.7,2.0,2.3,2.6 and 2.9 ng/ml.Anesthesia was induced with propofol TCI(effect-site concentration was set at 4.5 μg/ml)and TCI of remifentanil at 9 effect-site concentrations.One minute after the effect-site concentrations of propofol and remifentanil had been reached the patients'consciousness was evaluated.If conscious the effect-site concentration of remifentanil was increased until consciousness was lost.D&C was then started.If respiratory depression occurred(apnea＞1 min),the patient was mechanically ventilated via face mask.Anesthetic efficacy was evaluated on the basis of consciousness and the degree of body movement in response to surgical stimulus.Effective effect-site concentration(EC50,EC95)and respiratory depression effect-site concentration(EC50,EC95)were calculated using probit analysis.Results The effective effect-site concentration of remifentanil:EC50 was 1.67 ng/ml(95% confidence interval ranged from 1.45-1.90 ng/ml)and EC95 was 3.88ng/ml(95% confidence interval ranged from 3.08-5.89 ng/ml).The respiratory depression effect-site concentration of remifentanil:EC50 was 2.44 ng/ml(95% confidence interval ranged between 2.28-2.64 ng/ml),and EC95 was 3.36 ng/ml(95% confidence interval ranged between 2.99-4.34 ng/ml).Conclusion The effective and respiratory depression effect-site concentration(EC50,EC95)of remifentanil are 1.67,3.88;2.44,3.36 ng/ml respectively when used in combination with propofol TCI(effect-site concentration is set at 4.5 μg/ml)for dilatation and curettage.