[双谱指数与低于1个最低肺泡有效浓度的地氟醚浓度]

[Bispectral index and desflurane concentration below 1 MAC].

作者信息

Wrobel M, Kreuer S, Wilhelm W

机构信息

Klinik für Anaesthesiologie und Intensivmedizin, Universitätskliniken des Saarlandes.

出版信息

Anaesthesist. 2004 Jan;53(1):36-40. doi: 10.1007/s00101-003-0610-z.

DOI:10.1007/s00101-003-0610-z

PMID:14749874

Abstract

INTRODUCTION

We investigated the relationship between bispectral index (BIS, A-2000, Aspect Medical Systems, USA) and end-tidal desflurane concentrations below 1 MAC which is especially the range of interest if desflurane is combined with remifentanil for fast-track anaesthesia.

METHODS

With institutional review board approval and written informed consent we investigated 50 adult ASA I-III patients scheduled for minor orthopaedic surgical procedures. The BIS electrode (BIS-Sensor, Aspect Medical Systems, USA) was positioned on the patient's forehead as recommended by the manufacturer. All patients were premedicated with 0.15 mg x kg(-1) diazepam orally in the evening and on the morning before surgery. Induction of anaesthesia was started with a remifentanil infusion at 0.4 micro g x kg(-1) x min(-1) and 5 min later 2 mg x kg(-1) propofol was given for hypnosis. Immediately after intubation, remifentanil was reduced to 0.2 micro g x kg(-1) x min(-1), and the depth of anaesthesia was adjusted according to clinical needs by regulating the desflurane concentration. Starting 20 min after induction, a total of 1,483 data pairs, i.e. end-tidal desflurane concentrations with corresponding BIS values, was recorded. During surgery data pairs were analysed by linear regression analysis for each patient separately. During emergence from anaesthesia, desflurane effect compartment concentrations were simulated and non-linear regression analysis was applied.

RESULTS

We found a relationship between BIS ranges and mean end-tidal desflurane concentrations: A BIS range of 100-85 was related to 1.1+/-0.7 vol%, BIS 84-65 to 1.5+/-1.2 vol%, BIS 64-50 to 2.9+/-1.3 vol% and BIS 49-40 to 3.1+/-0.9 vol%. In particular, end-tidal desflurane concentrations related to these BIS ranges were significantly different from each other (ANOVA; P<0.05). Intraoperatively, we obtained a correlation coefficient of R=0.42+/-0.24 (mean+/-SD, range 0.05-0.96), during emergence from anaesthesia the correlation coefficient was R=0.84+/-0.12 (range 0.61-0.99).

CONCLUSION

We could demonstrate a relationship between bispectral index and end-tidal desflurane concentrations below 1 MAC with a BIS range of 49-40 being associated with approximately 0.5 MAC of desflurane during desflurane-remifentanil-anaesthesia.

摘要

引言

我们研究了脑电双频指数（BIS，A - 2000，美国Aspect Medical Systems公司）与低于1个最低肺泡有效浓度（MAC）的呼气末地氟烷浓度之间的关系，尤其是当地氟烷与瑞芬太尼联合用于快通道麻醉时，这一浓度范围是特别受关注的。

方法

经机构审查委员会批准并获得书面知情同意后，我们对50例计划进行小型骨科手术的成年美国麻醉医师协会（ASA）I - III级患者进行了研究。按照制造商的建议，将BIS电极（BIS - Sensor，美国Aspect Medical Systems公司）放置在患者前额。所有患者在手术前一晚及手术当天早晨口服0.15 mg/kg的地西泮进行术前用药。麻醉诱导开始时，以0.4 μg/kg·min⁻¹的速度输注瑞芬太尼，5分钟后给予2 mg/kg的丙泊酚进行催眠。插管后立即将瑞芬太尼剂量减至0.2 μg/kg·min⁻¹，并根据临床需要通过调节地氟烷浓度来调整麻醉深度。诱导后20分钟开始，共记录了1483对数据，即呼气末地氟烷浓度及其相应的BIS值。手术期间，对每位患者的数据对分别进行线性回归分析。在麻醉苏醒期，模拟地氟烷效应室浓度并应用非线性回归分析。

结果

我们发现BIS范围与平均呼气末地氟烷浓度之间存在关系：BIS范围为100 - 85时，对应地氟烷浓度为1.1±0.7 vol%；BIS 84 - 65时为1.5±1.2 vol%；BIS 64 - 50时为2.9±1.3 vol%；BIS 49 - 40时为3.1±0.9 vol%。特别是，与这些BIS范围相关的呼气末地氟烷浓度彼此之间存在显著差异（方差分析；P<0.05）。术中，我们得到的相关系数R = 0.42±0.24（平均值±标准差，范围0.05 - 0.96），在麻醉苏醒期，相关系数为R = 0.84±0.12（范围0.61 - 0.99）。