Editing Suspended animation (section)

==Delayed resuscitation in humans==
This condition of apparent [[death]] or interruption of vital signs in humans may be similar to a medical interpretation of suspended animation. It is only possible to recover signs of life if the brain and other vital organs suffer no cell deterioration, necrosis or [[molecular death]] principally caused by oxygen deprivation or excess temperature (especially high temperature).<ref>{{cite journal|url=http://gradestack.com/Dr-Bhatia-Medical/Molecular-death-is-A/2-3042-3166-15605-sf| title=Molecular death is|publisher=Forensic Medicine_gradestack.com}}</ref>

Cases have been reported of individuals having returned from this apparent interruption of life lasting over one half hour, two hours, eight hours, or more (while adhering to these specific conditions for oxygen and temperature) have been analysed in depth, but these cases are considered rare and unusual phenomena. The brain begins to die after five minutes without oxygen; nervous tissues die intermediately when a "somatic death" occurs while muscles die over one to two hours following this last condition.<ref>{{cite journal|url=http://gradestack.com/Dr-Bhatia-Medical/Definition-of-suspended/19-3042-3166-15605-sf|title=Definition of suspended animation is|publisher=Forensic Medicine_gradestack.com|access-date=6 June 2017|archive-date=29 June 2018|archive-url=https://web.archive.org/web/20180629074224/https://gradestack.com/Dr-Bhatia-Medical/Definition-of-suspended/19-3042-3166-15605-sf|url-status=dead}}</ref>

It has been possible to obtain a successful resuscitation and recover life after apparent suspended animation in such instances as after anaesthesia, heat stroke, electrocution, narcotic poisoning, heart attack or cardiac arrest, shock, newborn infants, cerebral concussion, or cholera.

Supposedly, in suspended animation, a person technically would not die, as long as they were able to preserve the minimum conditions in an environment extremely close to death and return to a normal living state. An example of such a case is [[Anna Bågenholm]], a Swedish radiologist who allegedly survived 80 minutes under ice in a frozen lake in a state of [[cardiac arrest]] with no brain damage in 1999.<ref>{{cite news|url=https://www.independent.co.uk/news/world/americas/miracle-student-survived-his-body-being-frozen-solid-a6823801.html |archive-url=https://ghostarchive.org/archive/20220525/https://www.independent.co.uk/news/world/americas/miracle-student-survived-his-body-being-frozen-solid-a6823801.html |archive-date=25 May 2022 |url-access=subscription |url-status=live| title='Miracle' student survived his body being frozen solid|newspaper=independent.co.uk|date=20 January 2016|access-date=5 June 2017}}</ref><ref>{{cite journal |vauthors=Gilbert M, Busund R, Skagseth A, Nilsen P, Solbo J |year=2000 |title=Resuscitation from accidental hypothermia of 13.7°C with circulatory arrest |journal=[[The Lancet]] |volume=355 |pages=375–376 |doi=10.1016/S0140-6736(00)01021-7 |issue=9201|pmid=10665559 |s2cid=54348869 }}</ref>

Other cases of [[hypothermia]] where people survived without damage are:
* John Smith, a 14-year-old boy who survived 15{{nbs}}minutes under ice in a frozen lake before paramedics arrived to pull him onto dry land and saved him.<ref>[http://www.medicaldaily.com/pulse/suspended-animation-how-boy-survived-15-minutes-trapped-under-ice-frozen-lake-321206 Suspended Animation? How A Boy Survived 15 Minutes Trapped Under Ice In Frozen Lake] at Medical Daily</ref>
* Mitsutaka Uchikoshi, a Japanese man, was reported by media to have survived the cold for 24{{nbs}}days in 2006 without food or water when he purportedly fell into a state similar to hibernation. This was doubted by some medical experts, claiming that surviving such a prolonged period without fluids was physiologically impossible.<ref>[http://news.bbc.co.uk/2/hi/asia-pacific/6197339.stm Japanese man in mystery survival] at BBC News</ref>{{Better source needed|reason=This case, if true, would be very exceptional. As such, as per WP:EXCEPTIONAL it requires exceptional sources. A case report from the medical scientific literature is needed here.|date=November 2021}}
* Paulie Hynek, who, at age two, survived several hours of hypothermia-induced cardiac arrest and whose body temperature reached {{convert|18|C|F}}.<ref>[http://mayoclinichealthsystem.org/local-data/press-releases/eau-claire/mayo-clinic-launches-national-mobile-exhibit-tour ''Eleva boy's story part of national tour to honor Mayo Clinics 150 years''] {{webarchive|url=https://web.archive.org/web/20150511022742/http://mayoclinichealthsystem.org/local-data/press-releases/eau-claire/mayo-clinic-launches-national-mobile-exhibit-tour |date=11 May 2015 }} Mayo Clinic</ref>
* [[Erika Nordby]], a toddler who in 2001 was revived after two hours without apparent heartbeat with a body temperature of about {{convert|16|C|F}}.<ref name=warick>{{cite news|work=Edmonton Journal|author=Warick, Jason|date=23 February 2002|page=A3|title='Miracle child' bears few scars one year after brush with death}}</ref>

=== Human hibernation ===
{{Main|Therapeutic hypothermia}}

It has been suggested that bone lesions provide evidence of hibernation among the early human population whose remains have been retrieved at the [[Archaeological site of Atapuerca]]. In a paper published in the journal ''L'Anthropologie'', researchers [[Juan Luis Arsuaga|Juan-Luis Arsuaga]] and Antonis Bartsiokas point out that "primitive mammals and primates" like bush babies and lorises hibernate, which suggests that "the genetic basis and physiology for such a hypometabolism could be preserved in many mammalian species, including humans".<ref>{{Cite news |last=Sullivan |first=R |date=2020 |title=Early humans may have hibernated |url=https://www.independent.co.uk/news/science/archaeology/early-humans-hibernation-winter-atapuerca-spain-b1776824.html |url-access=subscription |url-status=live |archive-url=https://ghostarchive.org/archive/20220525/https://www.independent.co.uk/news/science/archaeology/early-humans-hibernation-winter-atapuerca-spain-b1776824.html |archive-date=25 May 2022 |access-date=25 November 2021}} This article refers to Bartsiokas, A. & Arsuaga, J. (2020). ''Hibernation in hominins from Atapuerca, Spain half a million years ago''. [[L'Anthropologie]], Volume 124, Issue 5</ref>

Since the 1970s, [[deep hypothermic circulatory arrest|induced hypothermia]] has been performed for some [[heart surgery|open-heart surgeries]] as an alternative to [[heart-lung machine]]s. Hypothermia, however, provides only a limited amount of time in which to operate and there is a risk of tissue and brain damage for prolonged periods.

There are many research projects currently investigating how to achieve "induced [[hibernation]]" in humans.<ref>[http://www.livescience.com/health/050421_hibernation.html New Hibernation Technique might work on humans | LiveScience] at www.livescience.com</ref><ref>[https://web.archive.org/web/20080807172226/http://www.timesonline.co.uk/tol/news/uk/science/article1845294.ece Race to be first to 'hibernate' human beings - Times Online] at www.timesonline.co.uk</ref> This ability to hibernate humans would be useful for a number of reasons, such as saving the lives of seriously ill or injured people by temporarily putting them in a state of hibernation until treatment can be given.

The primary focus of research for human hibernation is to reach a state of [[torpor]], defined as a gradual physiological inhibition to reduce oxygen demand and obtain energy conservation by hypometabolic behaviors altering biochemical processes. In previous studies, it was demonstrated that physiological and biochemical events could inhibit endogenous thermoregulation before the onset of hypothermia in a challenging process known as "estivation". This is indispensable to survive harsh environmental conditions, as seen in some amphibians and reptiles.<ref>{{Cite journal |title=Is Human Hibernation Possible? |url=https://nature.berkeley.edu/garbelottoat/wp-content/uploads/lee2008-1.pdf |publisher=nature.berkeley.edu}}</ref>