Death

===Misdiagnosis===
{{See also|Premature burial}}
[[File:Wiertz burial.jpg|thumb|upright=1.2|''The Premature Burial'', [[Antoine Wiertz]]'s painting of a man buried alive, 1854]]

There are many anecdotal references to people being declared dead by physicians and then "coming back to life," sometimes days later in their coffin or when [[embalming]] procedures are about to begin. From the mid-18th century onwards, there was an upsurge in the public's fear of being mistakenly buried alive<ref>{{Harvnb|Bondeson|2001|p=77}}</ref> and much debate about the uncertainty of the signs of death. Various suggestions were made to test for signs of life before burial, ranging from pouring vinegar and pepper into the corpse's mouth to applying red hot pokers to the feet or into the [[rectum]].<ref>{{Harvnb|Bondeson|2001|pp=56,&nbsp;71.}}</ref> Writing in 1895, the physician J.C. Ouseley claimed that as many as 2,700 people were buried prematurely each year in England and Wales, although some estimates peg the figure to be closer to 800.<ref>{{Harvnb|Bondeson|2001|p=239}}</ref>

In cases of [[electric shock]], [[cardiopulmonary resuscitation]] (CPR) for an hour or longer can allow stunned [[nerve]]s to recover, allowing an apparently dead person to survive. People found unconscious under icy water may survive if their faces are kept continuously cold until they arrive at an [[emergency room]].<ref name=Limmer>{{cite book |title=Brady Emergency Care AHA |publisher=Prentice Hall |isbn=978-0-13-159390-9 |author1=Limmer, Dan |author2=O'Keefe, Michael F. |author3=Bergeron, J. David |author4=Grant, Harvey |author5=Murray, Bob |author6=Dickinson, Ed |edition=10th Updated |date=21 December 2006 |url-access=registration |url=https://archive.org/details/emergencycare0000unse }}</ref><!--original citation:Limmer, D. et al. (2006). Emergency care (AHA update, Ed. 10e). [[Prentice Hall]].--><!--guessed it was this:https://www.amazon.com/Brady-Emergency-Care-Updated-Edition/dp/0131593900/ --> This "diving response," in which [[metabolism|metabolic activity]] and oxygen requirements are minimal, is something humans share with [[cetacea]]ns called the [[mammalian diving reflex]].<ref name=Limmer />

As medical technologies advance, ideas about when death occurs may have to be reevaluated in light of the ability to restore a person to vitality after longer periods of apparent death (as happened when CPR and defibrillation showed that cessation of heartbeat is inadequate as a decisive indicator of death). The lack of electrical brain activity may not be enough to consider someone scientifically dead. Therefore, the concept of information-theoretic death has been suggested as a better means of defining when true death occurs, though the concept has few practical applications outside the field of [[cryonics]].<ref name="InfoDeath">{{cite web |last=Merkle |first=Ralph |title=Information-Theoretic Death |url=http://www.merkle.com/definitions/infodeath.html |url-status=live |archive-url=https://web.archive.org/web/20160809190714/http://www.merkle.com/definitions/infodeath.html |archive-date=9 August 2016 |access-date=4 June 2016 |website=merkle.com |quote="A person is dead according to the information-theoretic criterion if the structures that encode memory and personality have been so disrupted that it is no longer possible in principle to recover them. If inference of the state of memory and personality are feasible in principle, and therefore restoration to an appropriate functional state is likewise feasible in principle, then the person is not dead."}}</ref>