Mahmoodzadeh Hossein, Movafegh Ali, Beigi Nooshin Moosavi
Department of Surgery, Ali Shariati Hospital, Tehran Univ. of Medical Sciences, Tehran, Iran.
Middle East J Anaesthesiol. 2010 Feb;20(4):559-63.
Dextromethorphan (DM), the D-isomer of the codeine analogue levorphanol, is a weak, noncompetitive N-Methyl-D-Aspartate (NMDA) receptor antagonist. It has been suggested that NMDA receptor antagonists induce preemptive analgesia when administrated before tissue injury occurs, thus decreasing the subsequent sensation of pain.
The study was conducted in the Dr. Ali Shariati Hospital, Tehran University of Medical Sciences, Tehran, Iran. In this seventy two patients scheduled for elective cholesyctectomy between February 2005 and December 2006 were randomized into three equal groups to receive as premedication either oral dextromethorphan 45 mg (Group D45 = 24), dextromethorphan 90 mg (Group D 90 = 24) or placebo (Group C, n=24), 120 min before surgery. A visual analogue scale (VAS) for pain of each patient measured at arrival in the ward and 6 and 24 hours after surgery, was recorded.
The demographic characteristics of patients, ASA physical status class, duration of surgery, and the basal VAS pain score were similar in the two groups. There was no significant difference in the mean of the VAS pain scores measured over time or morphine consumption between three groups.
Dextromethorphan, 45 and 90 mg orally administrated 2 h before surgery had no effect on postoperative morphine requirement and pain intensity.
右美沙芬（DM）是可待因类似物左啡诺的D - 异构体，是一种弱的、非竞争性N - 甲基 - D - 天冬氨酸（NMDA）受体拮抗剂。有人提出，NMDA受体拮抗剂在组织损伤发生前给药时可诱导超前镇痛，从而减轻随后的疼痛感觉。
该研究在伊朗德黑兰医科大学阿里·沙里亚蒂博士医院进行。2005年2月至2006年12月期间计划进行择期胆囊切除术的72例患者被随机分为三组，每组人数相等，在手术前120分钟分别接受口服45毫克右美沙芬（D45组 = 24例）、90毫克右美沙芬（D90组 = 24例）或安慰剂（C组，n = 24例）作为术前用药。记录了每位患者在进入病房时以及手术后6小时和24小时测量的疼痛视觉模拟量表（VAS）。
两组患者的人口统计学特征、美国麻醉医师协会（ASA）身体状况分级、手术持续时间和基础VAS疼痛评分相似。三组之间随时间测量的VAS疼痛评分均值或吗啡消耗量没有显著差异。
术前2小时口服45毫克和90毫克右美沙芬对术后吗啡需求量和疼痛强度没有影响。
