Dreaming and awareness during dexmedetomidine- and propofol-induced unresponsiveness.
British Journal of Anaesthesia July 1, 2018 L Radek, R E Kallionpää, M Karvonen et al.
During anaesthetic-induced unresponsiveness, most people still have experiences, primarily internally generated dreaming rather than external awareness. In a study where healthy participants received stepwise infusions of dexmedetomidine or propofol, 84% of interviews conducted during periods of unresponsiveness contained reports of experiences (90% for dexmedetomidine, 74% for propofol). Internally generated experiences (dreaming) dominated 86% of reports, while externally generated experiences (awareness) were rare and linked to brief arousals. Participants receiving dexmedetomidine reported dreaming and awareness more often than those receiving propofol and recognized emotional sounds better (42% vs 15%), though none spontaneously mentioned sounds. Anaesthetic-induced unresponsiveness does not necessarily induce unconsciousness or disconnectedness.