Department of Medicine, Anaesthesiology and Intensive Care, University of Padova, Padova, Italy.
Department of Anaesthesia and Intensive Care, Integrated University Hospital of Verona, Verona, Italy.
Br J Anaesth. 2018 Jul;121(1):198-209. doi: 10.1016/j.bja.2018.02.019. Epub 2018 Mar 27.
General anaesthesia should prevent patients from experiencing surgery, defined as connected consciousness. The isolated forearm technique (IFT) is the current gold standard for connected consciousness monitoring. We evaluated the efficacy of different anaesthesia regimens in preventing IFT responses.
We conducted a systematic review with meta-analysis of studies evaluating IFT in adults. Proportions of IFT-positive patients were compared for inhalational versus intravenous anaesthesia and anaesthesia brain monitor (ABM)-guided versus non-ABM-guided.
Of 1131 patients in 22 studies, 393 (34.8%) had an IFT response during induction or maintenance. IFT-positive patients were less frequent during induction (19.7% [95% CI, 17.5-22.1]) than during maintenance (31.2% [95% CI, 27.8-34.8]). Proportions of IFT-positive patients during induction and maintenance were similar for inhalational (0.51 [95% CI, 0.38-0.65]) and intravenous (0.52 [95% CI, 0.26-0.77]) anaesthesia, but during maintenance were lower with inhalational (0.18 [95% CI, 0.08-0.38]) than with intravenous (0.48 [95% CI, 0.24-0.73]) anaesthesia. Proportions of IFT-positive patients during induction and maintenance were not significantly different for ABM-guided (0.64 [95% CI, 0.39-0.83]) and non-ABM-guided (0.48 [95% CI, 0.34-0.62]) anaesthesia but during maintenance were lower with non-ABM-guided (0.19 [95% CI, 0.09-0.37]) than with ABM-guided (0.57 [95% CI, 0.34-0.77]). Proportions of IFT-positive patients decreased significantly with increasing age and premedication use. Of the 34 anaesthesia regimens, 16 were inadequate. Studies had low methodological quality (only seven randomised controlled trials) and significant heterogeneity.
Standard general anaesthesia regimens might not prevent connected consciousness. More accurate anaesthesia brain monitor methodology to reduce the likelihood of connected consciousness is desirable.
全身麻醉应防止患者经历手术，即意识相连。孤立前臂技术（IFT）是目前监测意识相连的金标准。我们评估了不同麻醉方案预防 IFT 反应的效果。
我们对评估成人 IFT 的研究进行了系统评价和荟萃分析。比较了吸入性麻醉与静脉麻醉、麻醉脑监测（ABM）指导与非 ABM 指导下 IFT 阳性患者的比例。
在 22 项研究的 1131 名患者中，393 名（34.8%）在诱导或维持期间出现 IFT 反应。诱导期间 IFT 阳性患者的频率较低（19.7%[95%置信区间，17.5-22.1%]），维持期间较高（31.2%[95%置信区间，27.8-34.8%]）。诱导和维持期间，吸入性麻醉（0.51[95%置信区间，0.38-0.65]）和静脉麻醉（0.52[95%置信区间，0.26-0.77]）的 IFT 阳性患者比例相似，但维持期间，吸入性麻醉（0.18[95%置信区间，0.08-0.38%]）低于静脉麻醉（0.48[95%置信区间，0.24-0.73%]）。诱导和维持期间，ABM 指导（0.64[95%置信区间，0.39-0.83%]）和非 ABM 指导（0.48[95%置信区间，0.34-0.62%]）麻醉的 IFT 阳性患者比例无显著差异，但维持期间，非 ABM 指导（0.19[95%置信区间，0.09-0.37%]）低于 ABM 指导（0.57[95%置信区间，0.34-0.77%]）。IFT 阳性患者的比例随着年龄的增长和术前用药的使用而显著下降。在 34 种麻醉方案中，有 16 种是不充分的。研究的方法学质量较低（只有 7 项随机对照试验），存在显著的异质性。
标准全身麻醉方案可能无法预防意识相连。需要更准确的麻醉脑监测方法来降低意识相连的可能性。
