Heart disease health centre

A scientific explanation for near-death experiences?

8th April 2010  -- When some people are near-death they report sensations such as seeing a dark tunnel, or bright lights; others experience feelings of peace and joy. A new study finds there may be a rational explanation for what many see as a mystical or spiritual experience.

Researchers in Slovenia believe that raised levels of carbon dioxide in the blood may be a major factor provoking the sensations of a near-death experience.

They investigated unexplained events in 52 cardiac arrest survivors.

Carbon dioxide levels significantly higher

Zalika Klemenc-Ketis led the study, working with a team of researchers from the University of Maribor.

They examined the cases of patients who reported near-death experiences (NDEs) after resuscitation from cardiac arrest. More than one in five people who were successfully resuscitated after an out-of-hospital cardiac arrest experienced an NDE.

She said, “Several theories explaining the mechanisms of NDEs exist. We found that in those patients who experienced the phenomenon, blood carbon dioxide levels were significantly higher than in those who did not”.

Of the 52 patients, 11 reported NDEs. Their occurrence didn’t correlate with patients’ sex, age, level of education, religious belief, fear of death, recovery time, or medications given during resuscitation.

They were more common in people who had previously experienced NDEs.

According to Klemenc-Ketis, “Our study adds new and important information to the field of NDE phenomena. The association with carbon dioxide has never been reported before, and deserves further study”.

The research is published in BioMed Central’s open access journal Critical Care.

One piece of the puzzle

Clinical hypnotherapist Andrew T. Austin has a long-standing interest in near-death experiences from working as a nurse in Accident and Emergency in Southampton, where he saw a number of patients who reported having an NDE.

He says it’s quite possible that carbon dioxide levels may play a part in bringing on a NDE but it’s “only one piece of the puzzle”.

He says, “Often people are oxygen deprived and they have had a drop in blood pressure too”.

He says, “What may cause NDEs is the actual experience of nearly dying, the psychological shock of being about to check out”.

There’s no consensus on what causes NDEs. Some people believe they are evidence of life-after-death, others believe they are purely a neurological phenomenon or just a particularly vivid dream.