Opioids can increase sensitivity to noxious stimuli and cause opioid-induced hyperalgesia. We performed a systematic review to evaluate the clinical consequences of intra-operative doses of opioid.We identified randomized controlled trials which compared intra-operative opioid to lower doses or placebo in adult patients undergoing surgery from MEDLINE, EMBASE, LILAC, Cochrane, and hand searches of trial registries. We pooled data of postoperative pain intensity, morphine consumption, incidence of opioid-related side-effects, primary and secondary hyperalgesia. For dichotomous outcomes relative risks [95
作者：D, Fletcher；V, Martinez
来源：British journal of anaesthesia 2014 年 112卷 6期
