罗哌卡因复合舒芬太尼用于剖宫产术后硬膜外镇痛的半数有效浓度

EC50 of Ropivacaine Combined with Sufentanil for Epidural Analgesia after Cesarean Delivery

目的测定剖宫产术后硬膜外镇痛时罗哌卡因复合0.4mg.L-1舒芬太尼的半数有效浓度(EC50),为其临床应用提供参考依据。方法选择孕36～40周择期剖宫产术、ASAⅠ-Ⅱ级孕妇38例。复合舒芬太尼0.4mg.L-1。按照序贯法进行试验,硬膜外罗哌卡因的质量浓度分别由低到高设为1.0、1.25、1.5、1.75和2.0g.L-1,初始靶质量浓度为1.5g.L-1,若术后8h访视患者静息时视觉模拟评分(VAS)高于3分,则下一例患者采用高一级浓度的罗哌卡因;若患者术后VAS<3分,则下一例患者采用低一级浓度的罗哌卡因。采用序贯法计算公式,计算剖宫产术后硬膜外镇痛时罗哌卡因复合0.4mg.L-1舒芬太尼的EC50及其95%可信区间(CI)。同时记录术后运动阻滞发生率。结果 38例患者中20例硬膜外镇痛有效,18例患者硬膜外镇痛无效,有效镇痛患者术后运动阻滞发生率与无效患者比较差异无统计学意义(P>0.05)。剖宫产术后硬膜外镇痛时罗哌卡因复合0.4mg.L-1舒芬太尼的EC50为1.39g.L-1,95%CI为1.29～1.49g.L-1。结论罗哌卡因复合0.4mg.L-1舒芬太尼用于剖宫产术后镇痛EC50为1.39g.L-1,不良反应少,能够减轻剖宫产术后疼痛。

Objective To determine the half-effective concentration （ECs0） values of ropiva- caine combined with 0.4 mg. L-1 sufentanil for epidural analgesia after cesarean delivery, and to provide a reference for the clinical application. Methods Thirty-eight ASA I - I1 patients at 36-40 weeks＇ gestation were scheduled for cesarean delivery. The concentrations of ropivacaine were set at 1.0,1.25,1.5,1.75 and 2.0 g.L-1 using sequential trial design,and the initial concentration was set at 1.5 g.L-1. If VAS score was greater than 3 at 8 hours after operation,the next patient would receive a higher concentration of ropivacaine. If VAS score was less than 3, the next patient would receive a lower concentration of ropivacaine. ECs0 values and their 95 % confidence intervals were calculated using probit analysis. Moreover, the incidence of motor block was recorded after operation. Results Among the 38 patients,epidural analgesia was effective in 20 and ineffective in 18. There was no significant difference in the incidence of motor block between patients who un- derwent effective analgesia and patients who underwent ineffective analgesia（P〉0.05）. The ECs0 of ropivacaine was 1.39 g.L-1 and 95% confidence interval ranged from 1.29-1.49 g.L-1. Con- clusion The ropivacaine with an ECs0 at 1.39 g.L-1 combined with 0.4 mg.L-1 sufentanil for epidural analgesia after cesarean delivery can reduce postoperative pain with fewer adverse reac- tions.