De Kock M, Gautier P, Pavlopoulou A, Jonniaux M, Lavand'homme P
Department of Anesthesiology, University of Louvain, St. Luc Hospital, Brussels, Belgium.
Anesthesiology. 1999 May;90(5):1354-62. doi: 10.1097/00000542-199905000-00020.
The rationale of this study was to compare high-dose epidural clonidine with a more commonly used agent, such as bupivacaine. This was performed to give a more objective idea of the relative analgesic potency of epidural clonidine.
Sixty patients undergoing intestinal surgery during propofol anesthesia were studied. At induction, the patients received epidurally a dose of 10 micrograms/kg [corrected] clonidine in 7 ml saline followed by an infusion of 6 micrograms [corrected] x kg(-1) x h(-1) (7 ml/h) (group 1, n = 20), a dose of 7 ml bupivacaine, 0.5%, followed by 7 ml/h bupivacaine, 0.25% (group 2, n = 20), or a dose of 7 ml bupivacaine, 0.25%, followed by 7 ml/h bupivacaine, 0.125% (group 3, n = 20). Intraoperatively, increases in arterial blood pressure or heart rate not responding to propofol (0.5 mg/kg) were treated with intravenous alfentanil (0.05 mg/kg). Additional doses of propofol were given to maintain an adequate bispectral index. The epidural infusions were maintained for 12 h. In cases of subjective visual analogue pain scores up to 5 cm at rest or up to 8 cm during coughing, the patients were given access to a patient-controlled analgesia device.
During anesthesia, patients in group 1 required less propofol than those in groups 2 and 3 (78 [36-142] mg vs. 229 [184-252] mg and 362 [295-458] mg; P < 0.05) and less alfentanil than patients in group 3 (0 [0-0] mg vs. 11 [6-20] mg; P < 0.05). Analgesia lasted 380 min (range, 180-645 min) in group 1 versus 30 min (range, 25-40 min) in group 2 and 22 min (range, 12.5-42 min) in group 3 (P < 0.05). There was no suggestion of a hemodynamic difference among the three groups except for heart rates that were significantly reduced in patients in group 1. Sedation scores were significantly higher in this group during the first 2 h postoperatively.
Our results show that high doses of epidural clonidine potentiate general anesthetics and provide more efficient postoperative analgesia than the two bupivacaine dosage regimens investigated.
本研究的目的是比较高剂量硬膜外可乐定与更常用的药物，如布比卡因。这样做是为了更客观地了解硬膜外可乐定的相对镇痛效力。
研究了60例在丙泊酚麻醉下接受肠道手术的患者。诱导时，患者硬膜外给予7ml生理盐水中10微克/千克[校正后]可乐定，随后以6微克[校正后]×千克⁻¹×小时⁻¹（7ml/小时）输注（第1组，n = 20）；给予7ml 0.5%布比卡因，随后以7ml/小时输注0.25%布比卡因（第2组，n = 20）；或给予7ml 0.25%布比卡因，随后以7ml/小时输注0.125%布比卡因（第3组，n = 20）。术中，对丙泊酚（0.5mg/kg）无反应的动脉血压或心率升高，用静脉注射阿芬太尼（0.05mg/kg）治疗。给予额外剂量的丙泊酚以维持适当的脑电双频指数。硬膜外输注维持12小时。若静息时主观视觉模拟疼痛评分高达5cm或咳嗽时高达8cm，患者可使用患者自控镇痛装置。
麻醉期间，第1组患者所需丙泊酚少于第2组和第3组（78[36 - 142]mg对229[184 - 252]mg和362[295 - 458]mg；P < 0.05），所需阿芬太尼少于第3组（0[0 - 0]mg对11[6 - 20]mg；P < 0.05）。第1组镇痛持续380分钟（范围180 - 645分钟），第2组为30分钟（范围25 - 40分钟），第3组为22分钟（范围12.5 - 42分钟）（P < 0.05）。除第1组患者心率显著降低外，三组之间未显示出血流动力学差异。术后前2小时，该组的镇静评分显著更高。
我们的结果表明，高剂量硬膜外可乐定可增强全身麻醉药的效果，并比所研究的两种布比卡因给药方案提供更有效的术后镇痛。
