Dreaming and awareness during dexmedetomidine- and propofol-induced unresponsiveness.
Linda Radek, Roosa E Kallionpää, M Karvonen, Annalotta Scheinin, Anu Maksimow, Jaakko Långsjö, Kaike Kaisti, Tero Vahlberg, Antti Revonsuo, Harry Scheinin, Katja Valli
British Journal of Anaesthesia July 1, 2018 DOI: 10.1016/j.bja.2018.03.014 (opens in new tab)
Study at a glance
AI-extracted from the abstract| Characteristics | Randomized controlled trial Peer reviewed |
|---|---|
| Sample size | 47 |
| Population | Healthy participants |
| Interventions | dexmedetomidine propofol |
| Topics | Dreaming |
| Keywords | Awareness Consciousness Dexmedetomidine Interview Propofol |
| Registration | NCT01889004 |
| Key findings | Anaesthetic-induced unresponsiveness does not induce unconsciousness or necessarily even disconnectedness; most participants reported experiences, primarily dreaming, during periods of unresponsiveness. |
Abstract
Experiences during anaesthetic-induced unresponsiveness have previously been investigated by interviews after recovery. To explore whether experiences occur during drug administration, we interviewed participants during target-controlled infusion (TCI) of dexmedetomidine or propofol and after recovery. Healthy participants received dexmedetomidine (n=23) or propofol (n=24) in stepwise increments until loss of responsiveness (LOR1). During TCI we attempted to arouse them for interview (return of responsiveness, ROR1). After the interview, if unresponsiveness ensued with the same dose (LOR2), the procedure was repeated (ROR2). Finally, the concentration was increased 1.5-fold to achieve presumable loss of consciousness (LOC), infusion terminated, and the participants interviewed upon recovery (ROR3). An emotional sound stimulus was presented during LORs and LOC, and memory for stimuli was assessed with recognition task after recovery. Interview transcripts were content analysed. Of participants receiving dexmedetomidine, 18/23 were arousable from LOR1 and LOR2. Of participants receiving propofol, 10/24 were arousable from LOR1 and two of four were arousable from LOR2. Of 93 interviews performed, 84% included experiences from periods of unresponsiveness (dexmedetomidine 90%, propofol 74%). Internally generated experiences (dreaming) were present in 86% of reports from unresponsive periods, while externally generated experiences (awareness) were rare and linked to brief arousals. No within drug differences in the prevalence or content of experiences during infusion vs after recovery were observed, but participants receiving dexmedetomidine reported dreaming and awareness more often. Participants receiving dexmedetomidine recognised the emotional sounds better than participants receiving propofol (42% vs 15%), but none reported references to sounds spontaneously. Anaesthetic-induced unresponsiveness does not induce unconsciousness or necessarily even disconnectedness. NCT01889004.
Comparable studies
Other randomized controlled trials on dreaming, most cited first.
| Study | Year | Design | Participants |
|---|---|---|---|
| Efficacy of a Cognitive‐Behavioral Treatment for Insomnia and Nightmares in Afghanistan and Iraq Veterans With PTSD Combat veterans of Operation Enduring Freedom and/or Operation Iraqi Freedom (mean age... | 2013 | Randomized controlled trial | n = 40 |
| Lucid Dreaming Treatment for Nightmares: A Pilot Study Chronic nightmare sufferers | 2006 | Randomized controlled trial | n = 23 |
| Testing the involvement of the prefrontal cortex in lucid dreaming: A tDCS study Participants spending three consecutive nights in a sleep laboratory | 2013 | Randomized controlled trial | n = 19 |
| Pre-sleep treatment with galantamine stimulates lucid dreaming: A double-blind, placebo-controlled, crossover study Adults with high dream recall and an interest in lucid dreaming | 2018 | Randomized crossover trial | n = 121 |
| Studies with lucid dreaming as add-on therapy to Gestalt therapy Adults with nightmares (ICD-10: F51.5) at least twice a week | 2015 | Randomized controlled trial | n = 32 |
Citations in the library
Cited by 23
- The spectral exponent of the resting EEG indexes the presence of consciousness during unresponsiveness induced by propofol, xenon, and ketamine Neuroimage January 11, 2019
- General Anesthesia: A Probe to Explore Consciousness Frontiers in Systems Neuroscience August 14, 2019
- Foundations of Human Consciousness: Imaging the Twilight Zone. Journal of Neuroscience February 24, 2021
- Local orchestration of distributed functional patterns supporting loss and restoration of consciousness in the primate brain. Nature Communications March 11, 2024
- The nature of consciousness in anaesthesia BJA Open September 26, 2023
and 18 more in the library
Cites 9
- Unresponsiveness ≠ Unconsciousness Anesthesiology February 7, 2012
- Consciousness lost and found: subjective experiences in an unresponsive state. Brain and Cognition December 1, 2011
- Laboratory references in dreams: Methodological problem and/or evidence for the continuity hypothesis of dreaming? heiDOK (Heidelberg University) 2008
- General anaesthesia as fragmentation of selfhood: insights from electroencephalography and neuroimaging British Journal of Anaesthesia February 4, 2018
- Propofol dose and incidence of dreaming during sedation. European journal of anaesthesiology October 2009
and 4 more in the library