Department of Anaesthesia, Queen Victoria Hospital, East Grinstead,West Sussex RH19 3DZ, UK.
Br J Anaesth. 2013 Mar;110(3):432-7. doi: 10.1093/bja/aes387. Epub 2012 Dec 6.
Paracetamol formulations provide effective analgesia after surgery [Duggan ST, Scott LJ. Intravenous paracetamol (acetominophen). Drugs 2009; 69: 101-13; Toms L, McQuay HJ, Derry S, Moore RA. Single dose oral paracetamol (acetaminophen) for postoperative pain in adults. Cochrane Database Syst Rev 2008: CD004602]. I.V. paracetamol is superior to oral for pain rescue (Jarde O, Boccard E. Parenteral versus oral route increases paracetamol efficacy. Clin Drug Invest 1997; 14: 474-81). By randomized, double-blinded trial, we aimed to determine whether preoperative oral paracetamol provides inferior postoperative analgesia to preoperative i.v. paracetamol.
One hundred and thirty participants received either oral paracetamol and i.v. placebo (Group OP), or oral placebo and i.v. paracetamol (Perfalgan™) (Group IP). Oral preparations were given at least 45 min before surgery; i.v. preparations after induction of anaesthesia. Pain was assessed by a 100 mm visual analogue scale (VAS) 1 h from the end of surgery. Rescue analgesia was given on request.
A total of 128 patients completed the study. There were no significant differences in baseline characteristics or intraoperative variables between the groups. The study was designed to reveal whether OP is inferior to IP, with an inferiority margin of 20%. The number of patients reporting satisfactory analgesia at 1 h with VAS ≤ 30 mm were 15 (OP) and 17 (IP), respectively. The secondary outcome measure of the mean (standard deviation) VAS (mm) for the whole of each group was 52 (22) for OP and 47 (22) for IP. Analysis of confidence intervals indicates that oral paracetamol is not inferior to i.v. paracetamol. The median survival (90% CI) to rescue analgesia request was 54.3 (51.2-57.4) min in Group OP and 57.3 (55.4-59.2) min in Group IP; there was no significant difference in this measure.
In this study of lower third molar extraction, oral paracetamol is not inferior to i.v. for postoperative analgesia. ISRCTN Registration http://www.controlled-trials.com/ISRCTN77607163.
扑热息痛制剂在手术后能提供有效的镇痛效果[Duggan ST, Scott LJ. 静脉注射扑热息痛（对乙酰氨基酚）。药物 2009; 69: 101-13; Toms L, McQuay HJ, Derry S, Moore RA. 单次口服扑热息痛（对乙酰氨基酚）用于成人术后疼痛。Cochrane 数据库系统评价 2008: CD004602]。静脉注射扑热息痛在疼痛解救方面优于口服[Jarde O, Boccard E. 静脉内与口服途径增加扑热息痛的疗效。临床药物研究 1997; 14: 474-81]。通过随机、双盲试验，我们旨在确定术前口服扑热息痛是否会导致术后镇痛效果不如术前静脉注射扑热息痛。
130 名参与者分别接受口服扑热息痛和静脉注射安慰剂（OP 组）或口服安慰剂和静脉注射扑热息痛（Perfalgan™）（IP 组）。口服制剂在手术结束前至少 45 分钟给予；静脉注射制剂在麻醉诱导后给予。术后 1 小时使用 100mm 视觉模拟评分（VAS）评估疼痛。按需给予解救性镇痛。
共有 128 名患者完成了研究。两组在基线特征和术中变量方面无显著差异。本研究旨在确定 OP 是否劣于 IP，劣效性边界为 20%。在术后 1 小时，VAS≤30mm 的患者报告满意镇痛的人数分别为 OP 组 15 例和 IP 组 17 例。OP 组和 IP 组的 VAS（mm）均值（标准差）的次要终点测量结果分别为 52（22）和 47（22）。置信区间分析表明，口服扑热息痛并不劣于静脉注射扑热息痛。OP 组请求解救性镇痛的中位生存（90%CI）时间为 54.3（51.2-57.4）分钟，IP 组为 57.3（55.4-59.2）分钟；两组无显著差异。
在这项关于下颌第三磨牙拔除术的研究中，口服扑热息痛在术后镇痛方面并不劣于静脉注射。ISRCTN 注册 http://www.controlled-trials.com/ISRCTN77607163。
