Department of Anesthesiology and Pain Medicine, Seoul Medical Center, Seoul, Korea.
Korean J Anesthesiol. 2010 Dec;59(6):371-6. doi: 10.4097/kjae.2010.59.6.371. Epub 2010 Dec 31.
Propofol and remifentanil are usually co-administered and have shown synergistic effect for anesthesia. However, the synergistic effect of the two drugs on hypnosis measured by bispectral index (BIS) was controversial in previous studies. The aim of this study was to identify the interaction of propofol and remifentanil on BIS and the optimal dose combinations for hypnosis under 66% N(2)O during surgery.
Patients (age 55-75 and American Society of Anesthesiologists [ASA] 1-2) undergoing gastrectomy were enrolled in this study. Propofol and remifentanil were co-administered incrementally at 1 : 1 potent ratio (the P1R1 group), at 1 : 2 potent ratio (the P1R2 group), or at 2 : 1 potent ratio (the P2R1 group) using effect site target-controlled infusion and BIS was measured. 66% N(2)O was concomitantly administered to all groups. The dose-effect curves, the 90% effective dose (EC(90)) for adequate hypnosis (BIS 40), isobolograms and combination index were obtained by Calcusyn program (Biosoft) to reveal the interaction of propofol and remifentanil.
The P2R1 group showed synergistic action on BIS. However, the other groups needed larger amount of each drug than the doses of additive action. The EC(90) of the P2R1 group was propofol, 3.34 µg/ml and remifentanil, 2.41 ng/ml under 66% of N(2)O.
Propofol dominant co-administration is needed for dose reduction in BIS guided hypnosis.
丙泊酚和瑞芬太尼通常联合使用，并已显示出协同效应，可用于麻醉。然而，在以前的研究中，关于这两种药物对双频谱指数（BIS）测量的催眠作用的协同效应存在争议。本研究旨在确定丙泊酚和瑞芬太尼对 BIS 的相互作用，以及在手术中 66%氧化亚氮（N2O）下催眠的最佳剂量组合。
本研究纳入了接受胃切除术的年龄在 55-75 岁且美国麻醉医师协会（ASA）分级为 1-2 级的患者。采用效应部位靶控输注，以 1:1 效价比（P1R1 组）、1:2 效价比（P1R2 组）或 2:1 效价比（P2R1 组）递增联合给予丙泊酚和瑞芬太尼，并测量 BIS。所有组均同时给予 66%N2O。通过 Calcusyn 程序（Biosoft）获得剂量-效应曲线、足够催眠的 90%有效剂量（EC90，BIS 40）、等比图形和合并指数，以揭示丙泊酚和瑞芬太尼的相互作用。
P2R1 组在 BIS 上显示出协同作用。然而，其他组需要比相加作用的剂量更大的每种药物的量。在 66%的 N2O 下，P2R1 组的 EC90 为丙泊酚 3.34μg/ml，瑞芬太尼 2.41ng/ml。
在 BIS 指导的催眠下，需要丙泊酚主导的联合用药以减少剂量。
