Lehmann K A, Kratzenberg U, Schroeder-Bark B, Horrichs-Haermeyer G
Department of Anaesthesiology, University of Cologne, FRG.
Clin J Pain. 1990 Sep;6(3):212-20. doi: 10.1097/00002508-199009000-00008.
Forty patients (ASA status I-III) recovering from major orthopedic or gynecological operations were investigated to evaluate analgesic efficacy and threshold concentrations of tramadol and its main metabolite O-demethyltramadol (M1) in serum during the early postoperative period, using patient-controlled analgesia (PCA) by means of the Abbott Lifecare Infuser. Following an individualized intravenous loading dose of 97.5 +/- 42.3 mg (mean, SD), tramadol demand doses were 20 mg with a limit of 500 mg within 4 h; the lockout time was set to 5 min. The duration of PCA was 20.5 +/- 4.8 h. During this time 8.0 +/- 5.0 demands per patient were recorded, resulting in an average tramadol consumption of 257.5 +/- 102.8 mg (including loading dose). Analgesia was mostly judged good to excellent. Side effects were only of minor intensity and never gave rise to concern. There were no statistically significant differences between the types of surgery. Tramadol proved to be about 1/6 to 1/10 as potent an analgesic as morphine when both intensity and duration of effect were considered. Minimum effective tramadol serum concentration (MEC) varied greatly and could be best described by a log-normal distribution (range 20.2-986.3 ng/ml, median 287.7 ng/ml). Intraindividual MEC variability was lower than intersubject variability (38.2 vs 59.1%). Median M1 concentrations were 36.2 ng/ml.
对40例（ASA分级I-III级）接受大型骨科或妇科手术后正在康复的患者进行了研究，以评估曲马多及其主要代谢产物O-去甲基曲马多（M1）在术后早期血清中的镇痛效果和阈浓度，采用雅培生命关爱输注泵进行患者自控镇痛（PCA）。给予个体化静脉负荷剂量97.5±42.3mg（均值，标准差）后，曲马多的按需剂量为20mg，4小时内限量500mg；锁定时间设定为5分钟。PCA持续时间为20.5±4.8小时。在此期间，记录到每位患者平均有8.0±5.0次需求，曲马多平均消耗量为257.5±102.8mg（包括负荷剂量）。镇痛效果大多判定为良好至优秀。副作用仅为轻度，从未引起担忧。不同手术类型之间无统计学显著差异。当同时考虑镇痛强度和持续时间时，曲马多的镇痛效力约为吗啡的1/6至1/10。曲马多的最低有效血清浓度（MEC）差异很大，最好用对数正态分布描述（范围20.2-986.3ng/ml，中位数287.7ng/ml）。个体内MEC变异性低于个体间变异性（38.2%对59.1%）。M1浓度中位数为36.2ng/ml。
