Department of Anesthesiology, Duke University Medical Center, Durham, North Carolina, 2705, USA.
Curr Opin Anaesthesiol. 2011 Dec;24(6):665-9. doi: 10.1097/ACO.0b013e32834c7acf.
Devices using the electroencephalogram to estimate anesthetic depth have been available since 1996. Despite the use of these monitors for over a decade, there is little agreement among clinicians about the need for or value of depth of anesthesia monitoring. Since the majority of the studies evaluating the impact of depth of anesthesia monitoring on postoperative outcomes have utilized the bispectral index (BIS Covidian), this manuscript will focus on studies with this device. This review will evaluate the evidence that BIS monitoring can improve long-term outcomes.
BIS-guided anesthesia can reduce the incidence of awareness with recall in high-risk patients, but a recent study found that anesthetic management directed by an end-tidal anesthetic-agent concentration protocol is equally effective, and probably less expensive. Deep anesthesia (BIS < 45) during the intraoperative period is associated with increased postoperative mortality, but this relationship may be an epiphenomenon rather than causal.
There is growing concern that anesthetic management and even specific anesthetic agents may worsen outcomes in high-risk patients. There is, however, no conclusive evidence that depth of anesthesia monitors can improve outcomes and no evidenced-based reasons for anesthesia providers to change their current practice.
自 1996 年以来，已有使用脑电图来估计麻醉深度的设备。尽管这些监测器已经使用了十多年，但临床医生对于麻醉深度监测的必要性或价值仍存在很大分歧。由于评估麻醉深度监测对术后结果影响的大多数研究都使用了双频谱指数（BIS Covidian），因此本文将重点介绍该设备的研究。这篇综述将评估 BIS 监测可以改善长期结果的证据。
BIS 引导的麻醉可以降低高危患者中出现回忆的意识发生率，但最近的一项研究发现，根据呼气末麻醉剂浓度方案进行的麻醉管理同样有效，而且可能更便宜。术中深度麻醉（BIS<45）与术后死亡率增加相关，但这种关系可能是一种偶然现象而不是因果关系。
越来越多的人担心麻醉管理甚至特定的麻醉剂可能会使高危患者的预后恶化。然而，没有确凿的证据表明麻醉深度监测器可以改善结果，也没有基于证据的理由让麻醉提供者改变其当前的做法。
