Maternal-Fetal Medicine Unit, Department of Obstetrics and Gynaecology, University of Brescia, Italy.
Br J Anaesth. 2011 Feb;106(2):221-4. doi: 10.1093/bja/aeq317. Epub 2010 Nov 24.
The effects of epidural anaesthesia on maternal uteroplacental blood flow in the presence of uterine contractions remain unclear. The aim of our study was to evaluate the effects of epidural analgesia with bolus doses on uterine artery pulsatility index (UtA-PI) during labour.
In a prospective case-control study, UtA-PI was measured during uterine contraction and relaxation in nulliparous women in active labour with (epidural group) and without (control group) epidural analgesia. Patients in the two groups were matched for gestational age at delivery, American Society of Anesthesiologists physical status score, and cervical dilatation at the beginning of labour. In the epidural group, an epidural catheter was placed after prehydration with 500 ml i.v. saline, and sufentanil 2 μg ml⁻¹ (5 ml) and ropivacaine 1 mg ml⁻¹ (20 ml) were administered. UtA-PI was measured before (T0), 30 min (T30), and 90 min (T90) after the first administration of epidural analgesic drugs, during both uterine relaxation and contraction.
Fifty-two patients were included in the study, 33 in the epidural group and 19 in the control. UtA-PI was significantly higher in the epidural compared with the control group, only at T30 and during contraction. There were no differences in the rate of oxytocin augmentation, mode of delivery, birth weight, and umbilical artery pH between the two groups.
Epidural analgesia using ropivacaine 1 mg ml⁻¹ (20 ml) significantly reduced placental blood flow only transiently during uterine contraction 30 min after the injection. These changes did not seem to affect neonatal outcomes.
在存在子宫收缩的情况下，硬膜外麻醉对产妇子宫胎盘血流的影响尚不清楚。我们的研究目的是评估在分娩过程中使用单次剂量硬膜外镇痛对子宫动脉搏动指数（UtA-PI）的影响。
在一项前瞻性病例对照研究中，我们在活跃分娩的初产妇中测量了存在（硬膜外组）和不存在（对照组）硬膜外镇痛时子宫收缩和松弛期间的 UtA-PI。两组患者在分娩时的胎龄、美国麻醉医师协会身体状况评分和分娩开始时的宫颈扩张程度方面相匹配。在硬膜外组，在预补液 500ml 静脉生理盐水后放置硬膜外导管，并给予舒芬太尼 2μgml⁻¹（5ml）和罗哌卡因 1mgml⁻¹（20ml）。在第一次给予硬膜外镇痛药物前（T0）、30 分钟（T30）和 90 分钟（T90）测量 UtA-PI，在子宫松弛和收缩期间均进行测量。
本研究共纳入 52 例患者，其中 33 例在硬膜外组，19 例在对照组。与对照组相比，硬膜外组的 UtA-PI 仅在 T30 和收缩时明显更高。两组间催产素增强率、分娩方式、出生体重和脐动脉 pH 无差异。
在子宫收缩期间，单次注射 1mgml⁻¹（20ml）罗哌卡因的硬膜外镇痛仅在注射后 30 分钟短暂地降低了胎盘血流。这些变化似乎不会影响新生儿结局。
