上胸段硬膜外麻醉罗哌卡因和布比卡因的量效关系及效价比

Dose-effect Relationship and Potency Ratio of Ropivacaine and Bupivacaine on Upper Thoracic Epidural Anesthesia

目的:探讨以罗哌卡因和布比卡因行上胸段硬膜外麻醉的半数有效浓度(EC50)、95%有效浓度(EC95)和最佳有效浓度及其效价比。方法:选择拟施上胸段硬膜外麻醉ASAⅠ或Ⅱ级乳腺癌根治术病人197例,分为罗哌卡因组122例(R组)、布比卡因组75例(B组)。观察血压、心率、脉搏血氧饱和度,测定血气、麻醉平面,评价镇痛效果。结果:罗哌卡因和布比卡因的EC50分别为0.10%和0.09%,其效价比为1:0.9;EC95R组为0.14%,B组为0.12%,其效价比为1:0.86;最佳浓度R组为0.17%～0.18%,B组为0.14%～0.15%,其效价比为1:0.78;剂量分别为0.8～1.0mg/kg和0.75～0.85mg/kg。结论:上胸段硬膜外麻醉采用罗哌卡因和布比卡因的EC50和EC95麻醉时只对部分患者有效,而采用罗哌卡因和布比卡因的最佳浓度和剂量可获得镇痛完善、足够的阻滞平面和副作用最小的疗效。两药的效价比与浓度成正相关。

Objective To determine the effective concentrations of ropivacaine and bupivacaine in 50%（EC50） and 95 % （EC95） patients with upper thoracic epidural anesthesia, and to assess the optimal effective concentrations and the potency ratio. Methods One hundred and ninety-seven ASA Ⅰ or Ⅱ patients undergoing selective radical mastectomy with upper thoracic epidural anesthesia were randomly divided into two groups, ropivacaine group（n = 122） and bupiva- caine group（n = 75）. T2.3 interval was selected as a puncture site. A catheter was inserted into the epidural space in a cephalic direction for 3.5 -4.0 cm. Blood pressure（BP） heart rate （HR）, saturation of blood oxygen（SpO2）, blood gases analysis, segment of block and anesthesia effect were monitored during operation. Results the EC50 of ropivacaine and bupivacaine were 0.10% and 0.09% respectively in the two groups. The potency ratio of them was 1：0.9; the EC95 were 0.14% and 0.12%, the potency ratio was 1：0.86; the most effective concentrations of them were 0.17 - 0.18% and 0.14- 0.15%, the potency ratio was 1：0.78.The total amounts of first dose local anesthetics in the two groups were 20 ＋ 5 ml, and the dosages were 0. 8 - 1.0 mg· kg^- 1 and 0.75 - 0.85 mg· kg^- 1 Conclusion The best anesthesia effect, segments of block and minimal side effect can be achieved with the optimal concentrations of ropivacaine or bupivacaine selective radical mastectomy with upper thoracic epidural anesthesia. The potency ratio of two drugs was positively related to the drug concentration.