Brain State Monitoring: Current Research and Future Possibilities.

Processed electroencephalography (pEEG) devices have been used as depth of anesthesia monitors for over two decades to monitor anesthetic depth and reduce the incidence of awareness with recall (AWR). Each device has unique strengths and weaknesses. A growing body of evidence questions the ability of a pEEG-derived numerical indices to consistently, rapidly, and reliably quantify consciousness and prevent AWR in patients under general anesthesia.