序贯实验法测定布比卡因和罗哌卡因中胸段硬膜外镇痛的EC50

Determination of ECs0 of bupivacaine and ropivacaine for mid - thoracic epidural analgesia by up - down sequential allocation.

目的测定布比卡因和罗哌卡因用于上腹部术后中胸段硬膜外镇痛的EC50，探讨二者用于中胸段硬膜外镇痛的效价比。方法择期成年上腹部手术患者47例，随机分为罗哌卡因组和布比卡因组。全麻加硬膜外维持麻醉，术后患者自觉疼痛难忍时，硬膜外推注布比卡因或罗哌卡因药液10ml，药物浓度按序贯增减法调整，用100mmVAS评分法评估镇痛效果，VAS≤10镇痛有效，VAS〉10镇痛无效。按Dixon法计算布比卡因和罗哌卡因的EC50。结果布比卡因的EC50为0．073％，罗哌卡因的EC50为0．105％。结论罗哌卡因用于中胸段硬膜外术后镇痛的效能低于布比卡因。

Objective To determine the median effective concentration （EC50） of bupivacaine and ropivacine for mid -thoracic epidural analgesia, and compare the efficacy of the 2 analgesics. Methods 47 patients （ ASA Ⅰ -Ⅱ ） undergoing epigast surgery were randomly divided into bupivacaine group and ropivacaine group. Total anesthesia combined epidurai anesthesia was performed. After operation, 10ml bupivacaine or ropivacaine was injected into epidural with different concentration which was decided by up - down sequential allocation when patients could not tolerate pain. The analgesic efficacy was assessed with 100mm visual analog pain scores（VAS） ,and effectiveness was defined as VAS≤ 10mm. EC50 of bupivacaine and ropivacine was determined by the formula of Dixon. Result EC50 of bupivacaine and ropivaeine were 0.073% and 0. 105% respectively. Conclusion The Bupivacaine is better than Ropivacaine to use analgesia about thoracic segments epidural.