目的·通过序贯分析法确定择期剖宫产蛛网膜下腔联合硬膜外麻醉（腰硬联合麻醉）后90%产妇不发生低血压的去甲肾上腺素静脉推注剂量。方法·根据偏倚钱币序贯法依次对40例择期剖宫产的产妇进行前瞻性双盲序贯研究。主要观察指标为胎儿娩出前维持产妇收缩压高于其基础值80%所使用的去甲肾上腺素静脉推注剂量。次要观察指标包括头晕、胸闷、恶心、呕吐、心动过缓、继发性高血压、补救性使用阿托品的发生率、补救性使用去甲肾上腺素的发生率，以及新生儿1 min和5 min Apgar评分等。使用Isotonic回归分析估计90%有效剂量（90% effective dose，ED90）及其95%CI。结果·腰硬联合麻醉后预防性静脉推注去甲肾上腺素维持产妇血压的ED90为［10.85（95%CI 9.20～11.67）］ μg。产妇头晕、胸闷、恶心的发生率分别为2.5%、7.5%和10.0%，补救性使用去甲肾上腺素发生率为5.0%；未出现呕吐、心动过缓、继发性高血压及补救性使用阿托品。所有新生儿1 min及5 min Apgar评分均为10分。结论·建议剖宫产腰硬联合麻醉后单次静脉推注去甲肾上腺素11 μg，以预防产妇麻醉后低血压的发生。
SHEN Ting
,
XU Tao
,
ZHENG Jing
,
AN Xiao-hu
,
XU Zi-feng
,
CHAI Jing
. 去甲肾上腺素预防剖宫产腰硬联合麻醉后低血压的90%有效剂量的临床研究[J]. 上海交通大学学报（医学版）, 2020
, 40(11)
: 1495
-1499
.
DOI: 10.3969/j.issn.1674-8115.2020.11.010
Objective · To determine the optimal intravenous norepinephrine bolus dose needed to prevent hypotension after combined spinal and epidural anesthesia in 90% of women during elective cesarean delivery. Methods · Forty women undergoing elective cesarean delivery were allocated into this double-blinded, prospective, and sequential dose-finding study using biased coin design sequential method. The primary outcome was the successful use of the norepinephrine bolus dose to maintain systolic blood pressure above 80% of the baseline until delivery. Secondary outcomes included dizziness, breathlessness, nausea, vomiting, bradycardia, secondary hypertension and supplemental use of atropine or norepinephrine of the women, as well as 1 min and 5 min Apgar scores of the newborns. The 90% effective dose (ED90) and its 95%CI were estimated using Isotonic regression methods. Results · The estimated ED90 intravenous bolus dose of norepinephrine was [10.85 (95%CI 9.20-11.67)] μg to prevent hypotension after combined spinal and epidural anesthesia during cesarean delivery. The occurrence rates of dizziness, breathlessness, and nausea were 2.5%, 7.5% and 10.0%, respectively. The occurrence rate of additional rescue norepinephrine boluses was 5.0%. No vomiting, bradycardia, secondary hypertension and supplemental use of atropine appeared. Apgar scores of all newborns at 1 min and 5 min were 10. Conclusion · An intravenous norepinephrine bolus dose of 11 μg is recommended to prevent hypotension after combined spinal and epidural anesthesia during cesarean delivery for clinical practice.
