Department of Anesthesia and Pain Management, Mount Sinai Hospital, University of Toronto, Toronto, ON, Canada.
Department of Anesthesia and Pain Management, Mount Sinai Hospital, University of Toronto, 600 University Avenue, Room 19-103, Toronto, ON, M5G 1X5, Canada.
Can J Anaesth. 2019 Sep;66(9):1075-1081. doi: 10.1007/s12630-019-01407-7. Epub 2019 May 31.
The optimal epidural mixtures and settings for programmed intermittent epidural bolus (PIEB) labour analgesia have yet to be determined. A previous study by our group demonstrated that 10 mL boluses of bupivacaine 0.0625% with fentanyl 2 µg·mL administered every 40 min provided effective analgesia during the first stage of labour for 90% of women, without breakthrough pain. We wanted to determine the effective PIEB time interval of 5 mL boluses of bupivacaine 0.125% with fentanyl 2 µg·mL under the same study circumstances, aiming at a future comparative study.
This double-blind dose-finding study used the biased coin up-and-down sequential allocation method to determine the effective PIEB interval 90% (EI90) needed to provide effective analgesia without breakthrough pain during the first stage of labour. We used fixed 5 mL boluses of bupivacaine 0.125% with fentanyl 2 µg.mL and studied time intervals of 60, 50, 40, and 30 min. The first patient was assigned an interval of 60 min and the remaining intervals were assigned as per the biased coin up-and-down method.
The estimated EI90 was 36.5 min (95% confidence interval [CI], 34.0 to 39.0) by the truncated Dixon and Mood method and 34.2 min (95% CI, 30.8 to 41.5) by the isotonic regression method. We found that 20/40 women had an upper sensory block to ice above T6, 34/40 women had no motor block, and no woman required treatment for hypotension.
The EI90 between 5 mL boluses of bupivacaine 0.125% with fentanyl 2 µg·mL during the first stage of labour is approximately 35 min.
www.clinicaltrials.gov (NCT #02758405); registered 2 May, 2016.
程序化间歇硬膜外推注（PIEB）分娩镇痛的最佳硬膜外混合药物和设置仍有待确定。本研究组之前的一项研究表明，在第一产程中，每 40 分钟给予 10mL 布比卡因 0.0625%加芬太尼 2μg·mL 的负荷剂量，90%的产妇可获得有效的镇痛效果，且无爆发痛。我们希望在相同的研究条件下确定 5mL 布比卡因 0.125%加芬太尼 2μg·mL 的有效 PIEB 时间间隔，以便进行未来的比较研究。
这项双盲剂量探索研究采用偏倚硬币上下序贯分配法来确定在第一产程中提供有效镇痛而无爆发痛所需的有效 PIEB 间隔 90%（EI90）。我们使用固定的 5mL 布比卡因 0.125%加芬太尼 2μg·mL 的负荷剂量，并研究了 60、50、40 和 30min 的时间间隔。第 1 位患者被分配 60min 的间隔，其余间隔则根据偏倚硬币上下序贯法进行分配。
通过截断 Dixon 和 Mood 法估计的 EI90 为 36.5min（95%置信区间[CI]：34.0-39.0），通过等张回归法估计的 EI90 为 34.2min（95%CI：30.8-41.5）。我们发现，20/40 名女性的上半身对冰的感觉阻滞在上胸 6 水平以上，34/40 名女性无运动阻滞，无女性需要治疗低血压。
第一产程中，5mL 布比卡因 0.125%加芬太尼 2μg·mL 的负荷剂量的 EI90 约为 35min。
www.clinicaltrials.gov（NCT #02758405）；2016 年 5 月 2 日注册。
