【摘要】 目的探索超声引导逆行锁骨下臂丛神经阻滞的30 mL罗哌卡因的最佳浓度。方法对择期行上肢手术ASAⅠ~Ⅱ级的13例患者采用序贯法设计试验。罗哌卡因容量定为30 mL,以0.42%为初始浓度,相邻浓度之比为1∶1.2。以感觉神经阻滞完善(VAS<3)为有效。试验终止时不少于5个上-下周期。用Dixon-Massey公式计算半数有效浓度。比较不同浓度罗哌卡因对运动的阻滞效果。结果逆行锁骨下臂丛神经阻滞30 mL罗哌卡因的半数有效浓度为0.324%,0.35%浓度组的运动阻滞程度明显高于0.30%浓度组(P<0.01)。结论超声引导下逆行臂丛神经阻滞的30 mL罗哌卡因的最佳浓度为0.35%。更多还原

【Abstract】 Objective To determine the optimal concentration required to produce an effective retrograde infraclavicular brachial plexus block using an ultrasound(US)-guided technique.Methods Thirteen adults undergoing elective upper limb surgery received a US-guided retrograde infaclavicular block.The initial concentration of 30 mL ropivacaine was 0.42%,which was subsequently varied at a ratio of 1∶1.2 for each consecutive patient according to the response of the previous patient.The medium effective concentration(EC50) was determined using the Dixon and Massey up-and-down method.The degrees of motor block in the two concentration groups were compared.Results The EC50 of 30 mL ropivacaine was 0.324%.The motor block in 0.35% group was significantly better than that in 0.30% group(P<0.01).Conclusion The recommended concentration of 30 mL ropivacaine required for a US-guided retrograde infraclavicular block is 0.35% in clinical practice.更多还原