Department of Anesthesia, Akershus University Hospital, Lørenskog, Norway.
Institute of Clinical Medicine, University of Oslo, Oslo, Norway.
Acta Anaesthesiol Scand. 2018 Oct;62(9):1267-1273. doi: 10.1111/aas.13175. Epub 2018 Jun 25.
The combination of low-dose local anesthesia and lipophilic opioids such as fentanyl is established as a standard solution for labor epidural analgesia. Fentanyl increases efficacy, but may have negative effects on the neonate in terms of reduced neonatal neurologic and adaptive capacity scores and breast feeding. We hypothesized that addition of adrenaline 2 μg/mL to a solution of bupivacaine 1 mg/mL and fentanyl 2 μg/mL would reduce the systemic uptake of fentanyl, resulting in reduced serum fentanyl in the fetus at birth.
Forty-one nulliparous women requesting epidural analgesia were randomized to epidural analgesia with or without adrenaline. Blood samples were drawn from the mother with regular intervals, and at delivery. An umbilical vein blood sample (used as a proxy for fetal exposure) was drawn after clamping.
There were no significant differences between the groups in fentanyl concentrations in the umbilical vein and maternal serum at birth. There was a significantly lower mean area under the maternal serum-concentration curve for the first 2 hours of treatment in the adrenaline group (mean difference 0.161 nmol h/L [0.034; 0.289], P = .015), implying slower systemic uptake in the adrenaline group initially. There were no significant differences in treatment duration, motor block, Apgar scores, umbilical pH and base excess, or mode of delivery.
The addition of adrenaline to an epidural solution containing fentanyl lowered maternal systemic serum fentanyl concentration during the first 2 hours, but did not lower serum fentanyl concentration in the umbilical vein and mother at delivery.
低剂量局部麻醉与脂溶性阿片类药物（如芬太尼）联合应用于分娩硬膜外镇痛已被确立为标准方案。芬太尼可提高镇痛效果，但可能会降低新生儿神经和适应能力评分，以及母乳喂养率，从而对新生儿产生不良影响。我们假设在布比卡因 1mg/ml 和芬太尼 2μg/ml 的溶液中加入肾上腺素 2μg/ml，可减少芬太尼的全身摄取，从而降低胎儿出生时的血清芬太尼浓度。
41 名要求硬膜外镇痛的初产妇随机分为接受或不接受肾上腺素的硬膜外镇痛。定期从母亲和分娩时采集血样。夹闭脐带后抽取脐静脉血样（用作胎儿暴露的替代物）。
两组产妇和新生儿出生时脐静脉和血清中的芬太尼浓度无显著差异。肾上腺素组治疗后 2 小时内母体血清浓度曲线下面积明显较低（平均差异 0.161nmol h/L [0.034; 0.289]，P=0.015），提示肾上腺素组初始时芬太尼的全身摄取速度较慢。两组的治疗持续时间、运动阻滞、Apgar 评分、脐动脉 pH 值和碱剩余值或分娩方式均无显著差异。
在含有芬太尼的硬膜外溶液中加入肾上腺素可降低前 2 小时母体的血清芬太尼浓度，但不降低分娩时脐静脉和母体的血清芬太尼浓度。
