Chu C C, Shu S S, Lin S M, Chu N W, Leu Y K, Tsai S K, Lee T Y
Department of Anesthesiology, Veterans General Hospital-Taipei, Taiwan, R.O.C.
Acta Anaesthesiol Sin. 1995 Sep;33(3):149-54.
The use of neuraxial opioids has gained popularity over the last few years; they may augment the analgesia produced by the local anesthetic through direct binding with the specific spinal receptors. Morphine, a lipophobic opioid, may not be optimal as an intrathecal drug for intraoperative analgesia because of its slow onset. The lipophilic opioid, fentanyl for instance, if administered intrathecally, its onset is fast and many of its merits by virtue of its lipophilic property may be seen intraoperatively.
Seventy five healthy pregnant women who sustained cesarean section under spinal anesthesia were assessed in a randomized fashion. The spinal anesthetic used was 0.5% hyperbaric bupivacaine. Patients were divided into 5 groups, 15 in each group. Fentanyl 0 (Group I), 7.5 (Group II), 10 (Group III), 12.5 (Group IV) and 15 (Group V) micrograms was respectively added to normal saline to make a total volume of 0.3 ml, which was then added to bupivacaine and administered to patients in a randomized fashion. The effect of analgesia, vital signs and side effects were observed every 5 min during operation and every 30 min after operation.
It was disclosed that all patients in group V and IV had excellent analgesia intraoperatively, while only 33.3% patients in the control group had an analgesia which was qualified as excellent. Complete analgesia (time from injection to first report of pain) also lasted longer in group IV (201.3 +/- 16.4 min, mean +/- SEM) and group V (210.3 +/- 18.6 min) compared with group I (118.9 +/- 10.4 min). The duration of effective analgesia (time from injection to first parental opioid) was increased with the dose of intrathecal fentanyl above 12.5 micrograms (293 +/- 22.4 min). Both complete analgesia and effective analgesia were not significantly different between group IV and group V. Pruritus was the most common side effect. The incidence of shivering decreased significantly in group IV & V as compared with control group.
The combination of bupivacaine with a dose of fentanyl as low as 7.5 micrograms did not produce actual clinical effects. As the dose of fentanyl was increased to 12.5 micrograms or 15 micrograms the quality of surgical analgesia was better and the postoperative analgesia lasted longer. It seemed that the clinical effect might reach its ceiling at the dose of 12.5 micrograms. Pruritus was the most common side effect, but it was mild.
在过去几年中，神经轴索阿片类药物的使用越来越普遍；它们可能通过与特定的脊髓受体直接结合来增强局部麻醉药产生的镇痛效果。吗啡是一种亲水性阿片类药物，由于其起效缓慢，作为鞘内注射用于术中镇痛可能并非最佳选择。亲脂性阿片类药物，例如芬太尼，若鞘内给药，起效迅速，且术中可展现出许多因其亲脂性所具有的优点。
对75例在脊麻下行剖宫产术的健康孕妇进行随机评估。所用的脊麻药物为0.5%的高压布比卡因。患者被分为5组，每组15例。分别将0（I组）、7.5（II组）、10（III组）、12.5（IV组）和15（V组）微克的芬太尼加入生理盐水中配制成总体积为0.3 ml的溶液，然后加入布比卡因中并随机给予患者。术中每5分钟、术后每30分钟观察镇痛效果、生命体征及副作用。
结果显示，IV组和V组的所有患者术中镇痛效果均极佳，而对照组只有33.3%的患者镇痛效果为良好。IV组（201.3±16.4分钟，均值±标准误）和V组（210.3±18.6分钟）的完全镇痛（从注射到首次报告疼痛的时间）持续时间也比I组（118.9±10.4分钟）更长。鞘内芬太尼剂量高于12.5微克时，有效镇痛时间（从注射到首次使用静脉阿片类药物的时间）随剂量增加而延长（293±22.4分钟）。IV组和V组之间的完全镇痛和有效镇痛效果均无显著差异。瘙痒是最常见的副作用。与对照组相比，IV组和V组寒战的发生率显著降低。
布比卡因与低至7.5微克剂量的芬太尼联合使用未产生实际临床效果。当芬太尼剂量增加至12.5微克或15微克时，手术镇痛质量更佳，术后镇痛持续时间更长。似乎在12.5微克剂量时临床效果可能达到上限。瘙痒是最常见的副作用，但程度较轻。
