Near-death-experiences in out-of-hospital cardiac arrest survivors. Meaningful phenomena or just fantasy of death?

Frequent criticism concerning the investigation of near-death-experiences (NDEs) has been the lack of uniform nomenclature and the failure to control the studied population with an elimination of interfering factors such as administration of sedatives and nonspecific stress responses. Greyson's NDE Scale is a 16-item questionnaire developed to standardize further research into mechanisms and effects of NDEs. Using this scale, we interviewed good out-of-hospital cardiac arrest survivors, with documented time-intervals between call for help and restoration of spontaneous circulation, yet without obvious brain damage or known, psychiatric history. The incidence of such experiences appeared to be extremely low among survivors of genuine cardiac arrest events. Alteration of information processing under the influence of hypoxia and hypercarbia only occurs after several minutes of brain ischaemia. International multicentric data collection within the framework for standardized reporting of cardiac arrest events will be the only satisfying method to address this fascinating and intriguing issue.