A pre-print version of the Aware II paper is now available online. The final version may get locked away behind a paywall so its worth grabbing a copy now if interested: Awareness During Resuscitation – II: A Multi-Center Study of Consciousness and Awareness in Cardiac Arrest (PDF)
The AWARE and AWARE II studies attempted an empirical examination of patient’s experience of consciousness and the accompanying electrocortical biomarkers during cardiopulmonary resuscitation.
During the study, as well as recording an EEG, headphones playing an auditory cue were placed on patients being resusciated and a tablet containing visual targets was placed in such a way that it could only be seen from above.
It has been reported elsewhere that only 2-3% of patients who have been resuscitated report any form of NDE.
You can see the difficulty gathering any statistically significant information.
So. In this study, 567 patients were enrolled, but only 53 survived to discharge and only 28 of those were interviewed.
Of those who were interviewed:
- 39% reported broad perceptions or memories.
- 20% had a transcendent experience.
- 7% reported experiences consistant with CPR induced consciousness (eg feeling the chest compressions, feeling defibrillation etc).
- 7% reported auditory experience.
- 3.5% visual experience.
And unfortunatelly, no….nobody was able to recall the targets on the tablet devices.
Themes that occured in those who had a transcendent experience included:
- Undergoing an educational re-evaluation of life
- Perception of separation from the body
- Perception of heading towards a destination.
- Perception of returning to a place that felt like home.
The authors of the study warn that interpretation of these experiences is confounded by the fragmentation and loss of memories during the resuscitation as well as misinterpretation of experiences (for example combining memory fragments of ICU care into the resuscitation experience) and reporting through personal interpretation biases such as religious beliefs and reports of NDEs in the media.
Specifically the study concluded:
- Consciousness and awareness does occcur during cardiac arrest.
- Those experiences may be related to the quality of resuscitation efforts.
- Experiences during states of unconsciousness may impact longer-term psychological outcomes in survivors.
Well the first two points are not surprising. Working as an emergency department nurse, I occasionally witnessed patients become conscious and even talk during effective CPR in the midst of a ‘cardiac arrest’ (known as CPR induced consciousness).
What is interesting to me is the reported transcendent experiences and the longterm effects on the individuals involved.
If you want to take a fascinating deep dive into the aware study I recommend visitng AwareOfAware, a blog written by Dr Orson Wedgwood.