Chen L K, Lin C J, Huang C H, Wang M H, Lin P L, Lee C N, Sun W Z
Department of Anesthesiology, National Taiwan University Hospital, College of Medicine, Taipei, Taiwan.
Br J Anaesth. 2006 Feb;96(2):226-30. doi: 10.1093/bja/aei311. Epub 2005 Dec 23.
The transient effects of epidural bupivacaine 0.25-0.5% on the Doppler velocimetry of umbilical and uterine arteries had been reported, but the effects of continuous lower dose epidural bupivacaine (0.05-0.1%) infusion for labour analgesia have never been reported. In this study, we evaluated the effects of continuous epidural bupivacaine 0.075% on the Doppler velocimetry of uterine arteries.
Twenty pregnant women for labour analgesia received continuous epidural bupivacaine 0.075% infusion. We used a 4-MHz continuous-wave Doppler probe (Multigon 500A) with a 200 Hz thump filter to detect uterine blood flow velocity. We recorded the velocimetry data for uterine relaxation and contraction during five time periods: pre-epidural insertion, 1, 2, and 4 h post-epidural infusion, and after delivery of fetus.
Our data showed that the velocimetric indices of uterine vascular resistance were significantly increased 1, 2, and 4 h after epidural infusion when compared with the pre-epidural level; these returned to the baseline after delivery.
Continuous epidural analgesia with bupivacaine 0.075% increases the resistance of uterine artery and therefore possibly reduces the uterine blood flow.
已有报道0.25 - 0.5%的硬膜外布比卡因对脐动脉和子宫动脉多普勒测速的短暂影响，但连续低剂量硬膜外布比卡因（0.05 - 0.1%）输注用于分娩镇痛的影响尚未见报道。在本研究中，我们评估了连续硬膜外输注0.075%布比卡因对子宫动脉多普勒测速的影响。
20名接受分娩镇痛的孕妇接受连续硬膜外输注0.075%布比卡因。我们使用带有200 Hz重击滤波器的4 MHz连续波多普勒探头（Multigon 500A）来检测子宫血流速度。我们记录了五个时间段子宫舒张和收缩时的测速数据：硬膜外穿刺前、硬膜外输注后1、2和4小时以及胎儿娩出后。
我们的数据显示，与硬膜外穿刺前水平相比，硬膜外输注后1、2和4小时子宫血管阻力的测速指标显著增加；这些指标在胎儿娩出后恢复到基线水平。
连续硬膜外输注0.075%布比卡因进行镇痛会增加子宫动脉阻力，因此可能会减少子宫血流。
