腰麻病人瑞芬太尼和舒芬太尼呼吸抑制的半数血浆靶浓度

Respiratory depressant half-effective target plasma concentration of remifentanil and sufentanil during subarachnoid anesthesia

目的 测定腰麻病人靶控输注瑞芬太尼和舒芬太尼引起呼吸抑制的半数血浆靶浓度。方法 择期行腰麻手术病人40例，随机分为2组（n=20），瑞芬太尼组按序贯法靶控输注瑞芬太尼20min，相邻血浆靶浓度之间比值为1．5；舒芬太尼组按序贯法靶控输注舒芬太尼40min，相邻血浆靶浓度之间比值为1.2。根据呼吸频率、呼吸暂停时间、脉搏血氧饱和度、呼气末二氧化碳分压及动脉血气分析判定呼吸抑制。结果 瑞芬太尼引起呼吸抑制的半数血浆靶浓度为1．8μg·L^-1，95％可信区间为1．5～2．1μg·L^-1；舒芬太尼引起呼吸抑制的半数血浆靶浓度为0．23μg·L^-1，95％可信区间为0．21-0．25μg·L^-1。结论 腰麻时靶控输注瑞芬太尼和舒芬太尼引起呼吸抑制的半数血浆靶浓度分别为1．8μg·L^-1。和0．23μg·L^-1。

Objective To determine the half-effective target plasma concentration （Cp50） of remifentanil and sufentanil causing respiratory depression during subarachnoid anesthesia. Methods Forty ASA Ⅰ or Ⅱ patients aged 18-65 yr undergoing elective operation under subarachnoid anesthesia were randomly divided into 2 groups （ n = 20 each） ： A remifentanil group and B sufentanil group. The patients were unpremeditated. ECG, BP, HR, SpO2 and PrrCO2 were monitored before and during operation. Suharachnoid block was performed at I3-4 with bupivacaine 15 mg （0.75% bupivacaine 2 ml ＋ 10% glucose 1 ml）, The block height was 〈 T8 , TCI of remifentanil was started from target plasma concentration of 0.7μg·L^-1 and sufentanil 0.1μg·L^-1 , Cp50 was determined by up-and-down sequential trial, The ratio of two successive plasma concentrations were 1.5 （remifentanil） and 1.2 （sufentanil） respectively. Respiratory depression was defined as RR 〈 8 bpm or/and apnea 〉 15 sor/and SpO2 〈94% or/and PrrCO2 〉55 mm Hg. Results The Cp50 of remifentanil 1.8μg·L^-1（95% confidence interval 1.5-2.1μg·L^-1）. The Cp50 of sufentanil was 0.23μg·L^-1（95 % confidence interval 0.21- 0.25μg·L^-1 ）. Conclusion Cp50 of remifentanil by TCI causing respiratory depression was 1.8 μg·L^-1 and sufentanil 0.23μg·L^-1 .