■硬膜外非阿片类药物佐剂也减少了局部麻醉药的使用。我们的目的是检验假设,与目前的标准芬太尼相比,右美托咪定或艾氯胺酮联合局部麻醉药用于患者自控硬膜外镇痛(PCEA)时,局部麻醉药的每小时消耗量至少与此相当.
■总共招募了120名需要分娩镇痛的未分娩受试者进行最终统计分析。受试者随机接受0.075%罗哌卡因加三种等效佐剂之一:0.4μg/mL芬太尼,0.4μg/mL右美托咪定,或1.0毫克/毫升艾氯胺酮。主要结果是每小时消耗罗哌卡因。与芬太尼组相比,右美托咪定和艾氯胺酮组每小时局部麻醉药用量的20%差异被认为是临床差异(非劣效性).
■芬太尼组的每小时罗哌卡因消耗量为12.4(95%置信区间11.2至13.6)ml/h,因此,预设的非劣效性限值为2.5ml/h。芬太尼组的每小时罗哌卡因消耗量不逊于右美托咪定组(12.4ml/h与11.9ml/h,风险差异,0.5;95%置信区间CI,-1.0至2.0,符合非劣效性标准)。然而,艾氯胺酮组每小时的罗哌卡因消耗量为14.3ml/h,芬太尼组为12.4ml/h(风险差异,1.9,95%CI,0.2至3.6),未能确认非劣效性,非劣效性为20%。芬太尼组瘙痒发生率最高,而轻度头晕的发生率在艾氯胺酮组中最高。
■在设定本研究的条件时,与硬膜外芬太尼联合罗哌卡因用于分娩期间的PCEA相比,硬膜外右美托咪定的效果不差。同时,与硬膜外芬太尼联合罗哌卡因用于分娩镇痛相比,我们未能确定硬膜外用艾氯胺酮的非劣效性.
UNASSIGNED: Epidural nonopioid adjuvants also reduce local anesthetic use. We aimed to test the hypothesis that, compared with the present standard fentanyl, the hourly consumption of local anesthetic was at least as good when dexmedetomidine or esketamine was combined with local anesthetic for patient-controlled epidural analgesia (PCEA).
UNASSIGNED: A total of 120 laboring nulliparous subjects requiring labor analgesia were recruited for the final statistical analysis. Subjects were randomized to receive 0.075 % ropivacaine added with one of three equivalent adjuvants: 0.4 μg/mL fentanyl, 0.4 μg/mL dexmedetomidine, or 1.0 mg/mL esketamine. The primary outcome was hourly ropivacaine consumption. Compared with the fentanyl group, a 20 % difference in hourly local anesthetic consumption between the dexmedetomidine and esketamine groups was considered a clinical difference (non-inferiority margin).
UNASSIGNED: The hourly ropivacaine consumption of the fentanyl group was 12.4 (95 % confidence interval CI 11.2 to 13.6) ml/h, so the prespecified non-inferiority limit was 2.5 ml/h. The hourly ropivacaine consumption of the fentanyl group was not inferior to that of the dexmedetomidine group (12.4 ml/h vs. 11.9 ml/h, risk difference, 0.5; 95 % confidence interval CI, -1.0 to 2.0, meeting criteria for non-inferiority). However, the hourly ropivacaine consumption of the esketamine group was 14.3 ml/h, and that of the fentanyl group was 12.4 ml/h (risk difference, 1.9, 95 % CI, 0.2 to 3.6), failing to confirm non-inferiority with a non-inferiority margin of 20 %. The incidence of pruritus was highest in the fentanyl group, whereas the occurrence of mild dizziness was highest in the esketamine group.
UNASSIGNED: In setting of the conditions of this study, epidural dexmedetomidine was non-inferior compared with epidural fentanyl in combination with ropivacaine for PCEA during labor. Meanwhile, we failed to establish the non-inferiority of epidural esketamine compared with epidural fentanyl in combination with ropivacaine for labor analgesia.