Doctors in a Canadian intensive care unit have stumbled on a very strange case – when life support was turned off for four terminal patients, one of them showed persistent brain activity even after they were declared clinically dead.
For more than 10 minutes after doctors confirmed death through a range of observations, including the absence of a pulse and unreactive pupils, the patient appeared to experience the same kind of brain waves (delta wave bursts) we get during deep sleep. And it’s an entirely different phenomenon to the sudden ‘death wave’ that’s been observed in rats following decapitation.
“In one patient, single delta wave bursts persisted following the cessation of both the cardiac rhythm and arterial blood pressure (ABP),” the team from the University of Western Ontario in Canada reports.
They also found that death could be a unique experience for each individual, noting that across the four patients, the frontal electroencephalographic (EEG) recordings of their brain activity displayed few similarities both before and after they were declared dead.
“There was a significant difference in EEG amplitude between the 30-minute period before and the 5-minute period following ABP cessation for the group,” the researchers explain.