Capogna G, Celleno D, Fusco P, Lyons G, Columb M
Department of Anaesthesia, Fatebenefratelli General Hospital, Rome, Italy.
Br J Anaesth. 1999 Mar;82(3):371-3. doi: 10.1093/bja/82.3.371.
We have used the technique of randomized, double-blind sequential allocation to compare the minimum local analgesic concentrations (MLAC) of epidural bupivacaine and ropivacaine for women in the first stage of labour. The test bolus was 20 ml of local anaesthetic solution. The concentration was determined by the response of the previous woman to a higher or lower concentration of local anaesthetic, according to up-down sequential allocation. Efficacy was assessed using a 100-mm visual analogue pain score (VAPS). The test solution had to achieve a VAPS of 10 mm or less to be judged effective. For bupivacaine, MLAC was 0.093 (95% CI 0.076-0.110)% w/v, and for ropivacaine, 0.156 (95% CI 0.136-0.176)%w/v (P < 0.0001, 95% CI difference 0.036-0.090). The analgesic potency of ropivacaine was 0.60 (0.47-0.75) relative to bupivacaine. Claims for reduced toxicity and motor block must be considered with differences in analgesic potency in mind.
我们采用随机、双盲序贯分配技术，比较布比卡因和罗哌卡因用于分娩第一产程女性时的最低局部镇痛浓度（MLAC）。试验推注剂量为20 ml局部麻醉溶液。根据上下序贯分配法，浓度由前一位女性对更高或更低浓度局部麻醉药的反应来确定。使用100 mm视觉模拟疼痛评分（VAPS）评估疗效。试验溶液必须达到10 mm或更低的VAPS才能判定为有效。布比卡因的MLAC为0.093（95%CI 0.076 - 0.110）%w/v，罗哌卡因为0.156（95%CI 0.136 - 0.176）%w/v（P < 0.0001，95%CI差值0.036 - 0.090）。相对于布比卡因，罗哌卡因的镇痛效能为0.60（0.47 - 0.75）。在考虑毒性和运动阻滞降低的说法时，必须牢记镇痛效能的差异。
