Use of Cerebral State Index Monitoring to Detect Purposeful Movement in Unsedated Brain-injured Patients

Abstract

To test whether the cerebral state index (CSI) can be used as a measurement of the level of consciousness in unsedated brain-injured patients, 21 brain-injured adults were prospectively assessed in 77 separate sessions. After CSI monitoring was set up, the patient's motor responses to verbal and/or painful stimuli were assessed. CSI values were recorded before and after external stimulation. Purposeful movement in response to external stimuli was defined as command obeying and pain localization. Mean maximal CSI values increased significantly after external stimulation: from 71 to 89 and 49 to 62 in patients exhibiting purposeful and non-purposeful movements, respectively. The CSI value showed a high prediction probability (P_K < 0.8) for detecting purposeful movement to external stimuli, especially after external stimulation (P_K < 0.9). These results suggest that CSI monitoring might be a valid method for detecting purposeful movement in response to external stimuli in unsedated brain-injured patients.

Keywords

Brain injury Electroencephalogram Cerebral state index Intensive care unit Monitoring

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