Cobb Benjamin, Cho Yuri, Hilton Gillian, Ting Vicki, Carvalho Brendan
From the *Department of Anesthesiology, Perioperative and Pain Medicine, Stanford University School of Medicine, Stanford, California; †Pacific Alliance Medical Center, Los Angeles, California; and ‡Department of Anesthesia, Santa Clara Valley Medical Center, San Jose, California.
Anesth Analg. 2016 May;122(5):1490-7. doi: 10.1213/ANE.0000000000001181.
The aim of this study was to apply both IV fluid and forced-air warming to decrease perioperative hypothermia in women undergoing cesarean delivery with spinal anesthesia. The authors hypothesize that combined-modality active warming (AW) would increase maternal temperature on arrival at the postanesthesia care unit (PACU) and decrease the incidence of maternal perioperative hypothermia (<36°C) compared with no AW.
Forty-six healthy women (n = 23 per group) undergoing scheduled cesarean delivery with spinal anesthesia (10-12 mg bupivacaine + 10 μg fentanyl) were enrolled in this double-blinded, randomized controlled trial. Women were randomly assigned to receive either AW (warmed IV fluid and lower body forced-air warmer) or no warming (NW; blankets only). SpotOn Monitoring System was used to measure core temperature intraoperatively and for 1 hour postoperatively. The primary outcome measure was maternal temperature on arrival at the PACU. Secondary outcome measures included incidence of maternal perioperative hypothermia (<36°C), incidence of shivering, thermal comfort scores (0-100 scale), Apgar scores, and umbilical cord blood gas analysis.
Demographic, obstetric, and surgical data were similar between study groups. The AW group (35.9°C ± 0.5°C) had a significantly higher temperature on arrival at the PACU compared with the NW group (35.5°C ± 0.5°C, P = 0.006; 95% confidence interval of mean difference, 0.1°C-0.7°C). Fourteen (64%) women in the AW group and 20 (91%) in the NW group were hypothermic during the study period (P = 0.031). Median (interquartile range) thermal comfort scores were 100 (95-100) in the AW group and 90 (70-100) in the NW group (P = 0.008). There were no significant differences in the incidence of intraoperative shivering (22% in the AW and 45% in the NW groups; P = 0.11), Apgar scores, or umbilical vein blood gas values between the study groups.
Fluid combined with forced-air warming is effective in decreasing the incidence of perioperative hypothermia and improving maternal thermal comfort. However, despite multimodal AW, the majority of women became hypothermic, and shivering was not prevented. The findings suggest that combined AW for cesarean delivery with spinal anesthesia is difficult, and only modest benefit should be expected.
本研究旨在应用静脉输液和强制空气加温来降低接受脊髓麻醉剖宫产的女性围手术期体温过低的发生率。作者假设，与不进行主动加温（AW）相比，联合模式主动加温（AW）会使产妇到达麻醉后护理单元（PACU）时的体温升高，并降低产妇围手术期体温过低（<36°C）的发生率。
46名计划接受脊髓麻醉（10 - 12毫克布比卡因 + 10微克芬太尼）剖宫产的健康女性（每组n = 23）参与了这项双盲随机对照试验。女性被随机分配接受AW（加温静脉输液和下半身强制空气加温器）或不加温（NW；仅使用毛毯）。使用SpotOn监测系统在术中及术后1小时测量核心体温。主要结局指标是产妇到达PACU时的体温。次要结局指标包括产妇围手术期体温过低（<36°C）的发生率、寒战发生率、热舒适度评分（0 - 100分制）、阿氏评分以及脐动脉血气分析。
研究组之间的人口统计学、产科和手术数据相似。与NW组（35.5°C ± 0.5°C，P = 0.006；平均差异的95%置信区间为0.1°C - 0.7°C）相比，AW组到达PACU时的体温显著更高（35.9°C ± 0.5°C）。在研究期间，AW组有14名（64%）女性体温过低，NW组有20名（91%）女性体温过低（P = 0.031）。AW组的热舒适度评分中位数（四分位间距）为100（95 - 100），NW组为90（70 - 100）（P = 0.008）。研究组之间术中寒战发生率（AW组为22%，NW组为45%；P = 0.11）、阿氏评分或脐静脉血气值无显著差异。
液体联合强制空气加温可有效降低围手术期体温过低的发生率并改善产妇的热舒适度。然而，尽管采用了多模式AW，大多数女性仍出现体温过低，且未能预防寒战。研究结果表明，脊髓麻醉剖宫产联合AW操作困难，预期获益有限。
