van den Nieuwenhuyzen M C, Engbers F H, Burm A G, Lemmens H J, Vletter A A, van Kleef J W, Bovill J G
Department of Anaesthesiology, University Hospital Leiden, The Netherlands.
Anesthesiology. 1993 Sep;79(3):481-92; discussion 27A. doi: 10.1097/00000542-199309000-00011.
Although computer-controlled infusion (CCI) of alfentanil has been shown to be effective intraoperatively, this technique has not been validated for postoperative use. Therefore, the authors examined the efficacy of this technique in providing postoperative pain relief. The study comprised both a validation of published pharmacokinetic data sets and the definition of the minimum effective analgesic concentrations after major orthopedic surgery.
The bias and inaccuracy of the implemented pharmacokinetic data set were examined, in 20 patients who had undergone major orthopedic surgery, by determination of the median performance error (MDPE) and median absolute performance error (MDAPE). The performance of two other published pharmacokinetic data sets was also examined by simulating the plasma concentrations that would have been predicted, had these data sets been implemented. The minimum effective analgesic concentrations (MEAC) were determined at the following time points: at the onset of pain, at 9:00 PM on the day of surgery, and at 9:00 AM and 9:00 PM on the first postoperative day.
Measured plasma concentration-time profiles generally were parallel to the target concentration-time profiles. The MDPE and MDAPE obtained were 12% and 28%, respectively. The MEACs ranged from < 1 to 175 ng/ml and showed substantial interindividual variability. The median MEACs at the four study times were 59, 52, 65, and 43 ng/ml. The MEAC at 9:00 PM on the first postoperative day was significantly lower than those at the other study times (P < 0.05).
Computer-controlled infusion of alfentanil provides adequate postoperative analgesia. The study demonstrated that pharmacokinetic data sets that are useful for intraoperative CCI of alfentanil are equally valid in the postoperative phase. Although required plasma concentrations of alfentanil are reasonably stable in time, interindividual variations are large, necessitating individual titration.
尽管已证明计算机控制输注（CCI）阿芬太尼在术中有效，但该技术在术后使用尚未得到验证。因此，作者研究了该技术在提供术后疼痛缓解方面的疗效。该研究包括已发表的药代动力学数据集的验证以及大型骨科手术后最低有效镇痛浓度的定义。
在20例接受大型骨科手术的患者中，通过测定中位性能误差（MDPE）和中位绝对性能误差（MDAPE），检查所实施的药代动力学数据集的偏差和不准确性。还通过模拟如果实施这些数据集将会预测的血浆浓度，检查了其他两个已发表的药代动力学数据集的性能。在以下时间点确定最低有效镇痛浓度（MEAC）：疼痛发作时、手术当天晚上9点、术后第一天上午9点和晚上9点。
测得的血浆浓度-时间曲线通常与目标浓度-时间曲线平行。获得的MDPE和MDAPE分别为12%和28%。MEAC范围为<1至175 ng/ml，个体间差异很大。四个研究时间点的中位MEAC分别为59、52、65和43 ng/ml。术后第一天晚上9点的MEAC显著低于其他研究时间点（P<0.05）。
计算机控制输注阿芬太尼可提供充分的术后镇痛。该研究表明，对阿芬太尼术中CCI有用的药代动力学数据集在术后阶段同样有效。尽管阿芬太尼所需的血浆浓度在时间上相当稳定，但个体间差异很大，需要进行个体化滴定。
