Department of Anesthesiology and Intensive Care Medicine, Medical University of Graz, Graz, Austria.
Minerva Anestesiol. 2011 Apr;77(4):388-93. Epub 2010 Dec 9.
Anesthesiologists who work extended hours exhibit acute and chronic sleep deprivation. The newest bilateral Bispectral Index (BIS)-Vista monitor offers new advantages over earlier models, which include a new algorithm (version 1.4). One possible useful application for BIS monitoring of physiological sleep would be in critically ill patients who almost uniformly suffer from sleep disruption and deprivation because they loose their circadian rhythm due to the harsh noisy environment of critical care units. Previous studies, which used earlier versions of the BIS monitor to depict normal physiologic sleep, produced widely conflicting results. The aim of our study was to assess whether the new BIS-Vista monitor would exhibit a temporal decline that corresponds to natural physiologic sleep stages in healthy sleep-deprived, post-call anesthesiologists.
BIS-Vista sensors were bilaterally mounted, according to the manufacturer guidelines, onto the forehead of 10 healthy sleep-deprived volunteer anesthesiologists. Using the conventional Rechtschaffen and Kales criteria, BIS values during the awake, S1, S2, S3, S4, and rapid eye movement (REM) sleep stages were recorded.
Mean±SD BIS values during the awake, S1, S2, S3, S4, and REM sleep stages significantly declined for the left (96±2, 82±11, 73±10, 53±13, 43±11, 66±9) and right (97±2, 78±11, 69±9, 50±10, 39±13, 61±14) hemispheres respectively. There were no significant interhemispheric differences in BIS values over time (two-way ANOVA). However, in one subject, the left and right BIS values were mostly discordant throughout the recordings.
We demonstrated that although the BIS-Vista monitor was neither designed nor validated for monitoring normal physiologic sleep, it depicted a temporal decline that corresponds to normal physiologic sleep stages in sleep-deprived anesthesiologists.
长时间工作的麻醉师会经历急性和慢性睡眠剥夺。最新的双侧双谱指数（BIS）-Vista 监测仪与早期模型相比具有新的优势，包括新的算法（版本 1.4）。BIS 监测生理睡眠的一个可能有用的应用是在危重病患者中，由于重症监护病房嘈杂的恶劣环境，他们几乎普遍遭受睡眠中断和剥夺，因为他们失去了昼夜节律。先前使用早期版本 BIS 监测仪来描述正常生理睡眠的研究产生了广泛冲突的结果。我们的研究目的是评估新的 BIS-Vista 监测仪是否会表现出与健康睡眠剥夺后呼叫麻醉师的自然生理睡眠阶段相对应的时间下降。
根据制造商的指南，将 BIS-Vista 传感器双侧安装在 10 名健康睡眠剥夺的志愿麻醉师的额头上。使用传统的雷赫施芬和卡尔斯标准，记录 BIS 值在清醒、S1、S2、S3、S4 和快速眼动（REM）睡眠阶段。
左（96±2、82±11、73±10、53±13、43±11、66±9）和右（97±2、78±11、69±9、50±10、39±13、61±14）半球在清醒、S1、S2、S3、S4 和 REM 睡眠阶段的平均±SD BIS 值显著下降。左右半球的 BIS 值在时间上没有显著的半球间差异（双向 ANOVA）。然而，在一个受试者中，左右 BIS 值在整个记录过程中大多不一致。
我们证明，尽管 BIS-Vista 监测仪既不是为监测正常生理睡眠而设计也没有经过验证，但它描绘了睡眠剥夺麻醉师的正常生理睡眠阶段的时间下降。
