Laitio Ruut M, Kaskinoro Kimmo, Särkelä Mika O K, Kaisti Kaike K, Salmi Elina, Maksimow Anu, Långsjö Jaakko W, Aantaa Riku, Kangas Katja, Jääskeläinen Satu, Scheinin Harry
Turku Positron Emission Tomography (PET) Centre, and Department of Anesthesiology and Intensive Care, Turku University Hospital, Turku, Finland.
Anesthesiology. 2008 Jan;108(1):63-70. doi: 10.1097/01.anes.0000296106.52472.a6.
The aim was to evaluate the performance of anesthesia depth monitors, Bispectral Index (BIS) and Entropy, during single-agent xenon anesthesia in 17 healthy subjects.
After mask induction with xenon and intubation, anesthesia was continued with xenon only. BIS, State Entropy and Response Entropy, and electroencephalogram were monitored throughout induction, steady-state anesthesia, and emergence. The performance of BIS, State Entropy, and Response Entropy were evaluated with prediction probability, sensitivity, and specificity analyses. The power spectrum of the raw electroencephalogram signal was calculated.
The mean (SD) xenon concentration during anesthesia was 66.4% (2.4%). BIS, State Entropy, and Response Entropy demonstrated low prediction probability values at loss of response (0.455, 0.656, and 0.619) but 1 min after that the values were high (0.804, 0.941, and 0.929). Thereafter, equally good performance was demonstrated for all indices. At emergence, the prediction probability values to distinguish between steady-state anesthesia and return of response for BIS, State Entropy, and Response Entropy were 0.988, 0.892, and 0.992. No statistical differences between the performances of the monitors were observed. Quantitative electroencephalogram analyses showed generalized increase in total power (P < 0.001), delta (P < 0.001) and theta activity (P < 0.001), and increased alpha activity (P = 0.003) in the frontal brain regions.
Electroencephalogram-derived depth of sedation indices BIS and Entropy showed a delay to detect loss of response during induction of xenon anesthesia. Both monitors performed well in distinguishing between conscious and unconscious states during steady-state anesthesia. Xenon-induced changes in electroencephalogram closely resemble those induced by propofol.
目的是评估17名健康受试者在单药氙气麻醉期间麻醉深度监测仪双频谱指数（BIS）和熵指数的性能。
采用氙气面罩诱导和插管后，仅用氙气维持麻醉。在整个诱导期、稳态麻醉期和苏醒期监测BIS、状态熵和反应熵以及脑电图。通过预测概率、敏感性和特异性分析评估BIS、状态熵和反应熵的性能。计算原始脑电图信号的功率谱。
麻醉期间氙气浓度的平均值（标准差）为66.4%（2.4%）。BIS、状态熵和反应熵在反应消失时的预测概率值较低（分别为0.455、0.656和0.619），但此后1分钟时这些值较高（分别为0.804、0.941和0.929）。此后，所有指标均表现出同样良好的性能。在苏醒期，BIS、状态熵和反应熵区分稳态麻醉和反应恢复的预测概率值分别为0.988、0.892和0.992。未观察到监测仪性能之间的统计学差异。定量脑电图分析显示，全脑总功率（P < 0.001）、δ波（P < 0.001）和θ波活动（P < 0.001）普遍增加，额叶脑区α波活动增加（P = 0.003）。
脑电图衍生的镇静深度指标BIS和熵指数在氙气麻醉诱导期间检测反应消失存在延迟。两种监测仪在稳态麻醉期间区分清醒和无意识状态方面表现良好。氙气引起的脑电图变化与丙泊酚引起的变化非常相似。
