不同浓度罗哌卡因在坐骨神经阻滞中的半数有效剂量比较

Comparison of Half Effective Dose of Ropivacaine of different Concentration for Sciatic Nerve Block

目的:比较采用不同浓度罗哌卡因行坐骨神经阻滞时所需的半数有效剂量。方法:择期单侧足踝手术病人30例随机进入高浓度组(H组,n=15)或低浓度组(L组,n=15)。采用Probit概率单位回归法计算不同浓度罗哌卡因行坐骨神经阻滞的半数有效剂量。结果:高浓度组的半数有效剂量10.18 mL,低浓度组的半数有效剂量11 mL(P>0.05)。结论:采用0.375%和0.5%两种不同浓度罗哌卡因行坐骨神经阻滞时所需的半数有效剂量没有显著性差异。

Objective To compare half effective dose（ED50） of different ropivacaine for sciatic nerve block. Methods Thirty patients scheduled for foot or ankle surgery under the sciatic nerve block were randomly di-vided into the following two groups, one was high concentration group（group H ,n=15）, the other was low concen-tration group（group L,n=15）. Both groups of the patients were received the parasacal sciatic nerve block with the aid of nerve stimulator.The initial dose of both groups were 14 mL in the first patient and the ratio between the 2 successive doses was 1.2.The ED50 and 95% confidence interval（CI）of ropivacaine were calculated by Probit Regeression method. Results The ED50 and the 95% CI of 0.375%ropivacaine in patients of group L was 11 mL（9.46 mL-12.53 mL）, while those of 0.5% ropivacaine in patients of the group H was 10.18 mL（8.67 mL 1-1.17 mL）. There were no significant difference between the two groups. （P〉0.05）. Conclusion The ED50 of 0.375%and 0.5% ropivacaine for sciatic nerve block has no significant difference..