From the Departments of Anesthesiology.
Biostatistics, University of Arkansas for Medical Sciences, Little Rock, Arkansas.
Anesth Analg. 2021 Mar 1;132(3):666-675. doi: 10.1213/ANE.0000000000005141.
For emergent intrapartum cesarean delivery (CD), the literature does not support the use of any particular local anesthetic solution to extend epidural analgesia to cesarean anesthesia. We hypothesized that 3% chloroprocaine (CP) would be noninferior to a mixture of 2% lidocaine, 150 µg of epinephrine, 2 mL of 8.4% bicarbonate, and 100 µg of fentanyl (LEBF) in terms of onset time to surgical anesthesia.
In this single-center randomized noninferiority trial, adult healthy women undergoing CD were randomly assigned to epidural anesthesia with either CP or LEBF. Sensory blockade (pinprick) to T10 was established before operating room (OR) entry for elective CD. On arrival to the OR, participants received the epidural study medications in a standardized manner to simulate the conversion of "epidural labor analgesia to surgical anesthesia." The primary outcome was the time to loss of touch sensation at the T7 level. A noninferiority margin was set at 3 minutes. The secondary outcome was the need for intraoperative analgesia supplementation.
In total, 70 women were enrolled in the study. The mean onset time to achieve a bilateral sensory block to touch at the T7 dermatome level was 655 (standard deviation [SD] = 258) seconds for group CP and 558 (269) seconds for group LEBF, a difference in means of 97 seconds (90% confidence interval [CI], SD = -10.6 to 204; P = .10 for noninferiority). The upper limit of the 90% CI for the mean difference exceeded the prespecified 3-minute noninferiority margin. There was no meaningful difference in the requirement for intraoperative analgesia between the 2 groups.
Both anesthetic solutions have a rapid onset of anesthesia when used to extend low-dose epidural sensory block to surgical anesthesia. Data from the current study provide insufficient evidence to confirm that CP is noninferior to LEBF for rapid epidural extension anesthesia for CD, and further research is required to determine noninferiority.
对于紧急情况下的剖宫产（CD），文献不支持使用任何特定的局部麻醉溶液来将硬膜外镇痛延长至剖宫产麻醉。我们假设 3%氯普鲁卡因（CP）在手术麻醉起效时间方面与 2%利多卡因、150μg 肾上腺素、2mL8.4%碳酸氢钠和 100μg 芬太尼（LEBF）的混合物无差异。
在这项单中心随机非劣效性试验中，接受 CD 的成年健康女性被随机分配接受 CP 或 LEBF 硬膜外麻醉。在进入手术室（OR）进行选择性 CD 之前，建立 T10 的感觉阻滞（刺痛）。到达 OR 后，参与者以标准化的方式接受硬膜外研究药物，以模拟“硬膜外分娩镇痛转为手术麻醉”。主要结局是 T7 水平触觉丧失的时间。设定了 3 分钟的非劣效性边界。次要结局是术中镇痛补充的需要。
共有 70 名女性参加了这项研究。达到双侧 T7 皮区触觉阻滞的平均起效时间为 CP 组 655（标准差 [SD] = 258）秒，LEBF 组 558（269）秒，平均差异为 97 秒（90%置信区间 [CI]，SD = -10.6 至 204；P =.10 用于非劣效性）。平均差异的 90%CI 的上限超过了预设的 3 分钟非劣效性边界。两组术中镇痛需求无显著差异。
当用于将低剂量硬膜外感觉阻滞延长至手术麻醉时，两种麻醉溶液的麻醉起效均很快。当前研究的数据提供的证据不足以确认 CP 在快速硬膜外扩展麻醉用于 CD 方面与 LEBF 无差异，需要进一步研究来确定非劣效性。
