Department of Anesthesia and Perioperative Medicine, University of Manitoba, Winnipeg, MB R3T 2N2 Canada.
Anesth Analg. 2013 Mar;116(3):541-8. doi: 10.1213/ANE.0b013e31827b117e. Epub 2013 Feb 11.
Bispectral Index (BIS)-guided anesthesia administration has been reported to reduce the time to tracheal extubation. However, no trials have compared the ability of BIS guidance to promote earlier tracheal extubation relative to guidance by end-tidal anesthetic concentration (ETAC). We hypothesized that BIS-guided anesthesia would result in earlier tracheal extubation compared with ETAC-guided anesthesia in fast-track cardiac surgery patients.
This study consisted of patients at a single institution who were enrolled in the larger, multicenter BIS or Anesthesia Gas to Reduce Explicit Recall (BAG-RECALL) clinical trial that compared rates of postoperative awareness for patient whose anesthetic was guided by BIS versus ETAC. Patients undergoing cardiac surgery were randomized to BIS (n = 361) or ETAC (n = 362) guided anesthesia. Volatile anesthetic was titrated either to maintain a BIS value of 40 to 60 (BIS group), or an age-adjusted minimum alveolar concentration of 0.7 to 1.3 (ETAC group). In the ETAC group, anesthesiologists were blinded to the BIS values. In this substudy, time to tracheal extubation was compared between groups. Cox regression identified predictors affecting the instantaneous probability of tracheal extubation.
Time to tracheal extubation was not significantly different between groups (odds ratio 1.04, 95% confidence interval, 0.88-1.23, P = 0.643). In addition, group assignment did not influence the instantaneous probability of tracheal extubation (P = 0.433). Predictors decreasing the instantaneous probability of tracheal extubation included higher body mass index (P = 0.001), higher logistic EuroSCORE (P = 0.015), complex surgery type (P = 0.034), and surgery completion in the evening (P = 0.03).
Compared with management based on ETAC, anesthetic management based on BIS guidance does not strongly increase the probability of earlier tracheal extubation in patients undergoing fast-track cardiac surgery. The decision to extubate the trachea is more influenced by patient characteristics and perioperative course than the assignment to BIS or ETAC monitoring.
双频谱指数（BIS）指导下的麻醉管理已被报道可减少气管拔管时间。然而，尚无试验比较 BIS 指导与呼气末麻醉浓度（ETAC）指导在促进快速通道心脏手术患者更早气管拔管方面的能力。我们假设与 ETAC 指导的麻醉相比，BIS 指导的麻醉会导致快速通道心脏手术患者更早的气管拔管。
这项研究包括在一家机构的患者，他们参加了更大规模的多中心 BIS 或麻醉气体减少明确回忆（BAG-RECALL）临床试验，该试验比较了接受 BIS 与 ETAC 指导的麻醉的患者术后意识发生率。接受心脏手术的患者被随机分配至 BIS（n=361）或 ETAC（n=362）指导的麻醉。挥发性麻醉剂的滴定要么维持 40 至 60 的 BIS 值（BIS 组），要么维持年龄调整后的最低肺泡浓度为 0.7 至 1.3（ETAC 组）。在 ETAC 组中，麻醉师对 BIS 值是盲法的。在这项子研究中，比较了两组之间气管拔管的时间。Cox 回归确定了影响气管拔管瞬时概率的预测因素。
两组之间气管拔管时间无显著差异（优势比 1.04，95%置信区间，0.88-1.23，P=0.643）。此外，组分配不影响气管拔管的瞬时概率（P=0.433）。降低气管拔管瞬时概率的预测因素包括较高的体重指数（P=0.001）、较高的 logistic EuroSCORE（P=0.015）、复杂的手术类型（P=0.034）和晚上完成手术（P=0.03）。
与基于 ETAC 的管理相比，基于 BIS 指导的麻醉管理并未在快速通道心脏手术患者中强烈增加更早气管拔管的概率。气管拔管的决定更多地受到患者特征和围手术期过程的影响，而不是 BIS 或 ETAC 监测的分配。
