Li D F, Rees G A, Rosen M
Br J Anaesth. 1985 Mar;57(3):264-70. doi: 10.1093/bja/57.3.264.
The efficacy of an extradural infusion of 0.0625% or 0.125% bupivacaine was studied in 98 primigravid mothers in active labour. No special measures were taken to posture the mother (except to avoid aorto-caval compression). The study regimen included a control group (no infusion) receiving intermittent top-ups (0.25%. bupivacaine 8-10 ml), two groups receiving bupivacaine 6.25 mg h-1 infusion in different concentrations (0.0625% and 0.125%), a fourth group receiving 0.125% bupivacaine 12.5 mg h-1 infusion, and a fifth group receiving 0.125% bupivacaine 18.75 mg h-1 infusion. The optimum infusion rate was 0.125% bupivacaine 10 ml h-1, at which 69% of primigravid mothers required none or only one "top-up" of 0.25% bupivacaine 8-10 ml during a mean duration of 7.1 h labour. In the group who had no extradural infusion, only 32% of mothers managed with one or no top-up. The median interval between top-ups was increased from 145 min in the no infusion group to 245 min in those mothers receiving 0.125% bupivacaine 10 ml h-1 by infusion. Increasing the rate of infusion to 15 ml h-1 did not improve the results. Spread of local anaesthetic to higher levels was limited (less than T5) so that testing sensory loss at the T5-6 level at 2-hourly intervals should detect accidental spinal blockade resulting from inadvertent intrathecal infusion.
在98名处于活跃期的初产妇中研究了硬膜外输注0.0625%或0.125%布比卡因的疗效。未采取特殊措施让产妇保持体位（除避免主动脉-腔静脉受压外）。研究方案包括一个对照组（不输注），接受间歇性追加剂量（0.25%布比卡因8 - 10 ml），两组接受不同浓度（0.0625%和0.125%）的布比卡因6.25 mg/h输注，第四组接受0.125%布比卡因12.5 mg/h输注，第五组接受0.125%布比卡因18.75 mg/h输注。最佳输注速率为0.125%布比卡因10 ml/h，在此速率下，69%的初产妇在平均7.1小时的产程中无需或仅需一次0.25%布比卡因8 - 10 ml的“追加剂量”。在未进行硬膜外输注的组中，只有32%的产妇只需一次或无需追加剂量。追加剂量之间的中位间隔时间从无输注组的145分钟增加到接受0.125%布比卡因10 ml/h输注的产妇的245分钟。将输注速率提高到15 ml/h并未改善结果。局部麻醉药向更高平面的扩散受限（低于T5），因此每隔2小时在T5 - 6平面检测感觉丧失应能发现因无意鞘内输注导致的意外脊髓阻滞。
