Suspended animation

Suspended animation is understood as the pausing of life processes by external or internal means without terminating life itself.{{Cite journal|last=Asfar|first=P.|date=2014|title=Is pharmacological, H2S-induced 'suspended animation' feasible in the ICU?|journal=Critical Care|volume=182|issue=2|pages=215|doi=10.1186/cc13782|pmid=25028804|pmc=4060059 |doi-access=free }} Breathing, heartbeat and other involuntary functions may still occur, but they can only be detected by artificial means.{{cite magazine|url=https://www.scientificamerican.com|title=How do frogs survive winter? Why don't they freeze to death?|magazine=Scientific American|date=11 July 2014|access-date=3 June 2017}} For this reason, this procedure has been associated with a lethargic state in nature when animals or plants appear, over a period, to be dead but then can wake up or prevail without suffering any harm. This has been termed in different contexts hibernation, dormancy or anabiosis (the latter in some aquatic invertebrates and plants in scarcity conditions).

File:13C and 15N incorporation in representative microbial cells.webp

In July 2020, marine biologists reported that aerobic microorganisms (mainly), in "quasi-suspended animation", were found in organically-poor sediments, up to 101.5 million years old, {{convert|68.9|m|ft|abbr=off}} below the sea floor in the South Pacific Gyre (SPG) ("the deadest spot in the ocean"), and could be the longest-living life forms ever found.{{cite news |last=Wu |first=Katherine J. |title=These Microbes May Have Survived 100 Million Years Beneath the Seafloor - Rescued from their cold, cramped and nutrient-poor homes, the bacteria awoke in the lab and grew. |work=The New York Times |url=https://www.nytimes.com/2020/07/28/science/microbes-100-million-years-old.html |date=28 July 2020 |access-date=31 July 2020 }}{{cite journal |author=Morono, Yuki |display-authors=et al. |title=Aerobic microbial life persists in oxic marine sediment as old as 101.5 million years |date=28 July 2020 |journal=Nature Communications |volume=11 |number=3626 |page=3626 |doi=10.1038/s41467-020-17330-1 |pmid=32724059 |pmc=7387439 |bibcode=2020NatCo..11.3626M }}

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).{{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}}

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.{{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}}

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.{{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}}{{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 }}

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.[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
• 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.[http://news.bbc.co.uk/2/hi/asia-pacific/6197339.stm Japanese man in mystery survival] at BBC News{{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}}.[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
• 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}}.{{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}}

{{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 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".{{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

Since the 1970s, induced hypothermia has been performed for some open-heart surgeries as an alternative to heart-lung machines. 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.[http://www.livescience.com/health/050421_hibernation.html New Hibernation Technique might work on humans | LiveScience] at www.livescience.com[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 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.{{Cite journal |title=Is Human Hibernation Possible? |url=https://nature.berkeley.edu/garbelottoat/wp-content/uploads/lee2008-1.pdf |publisher=nature.berkeley.edu}}

Lowering the temperature of a substance reduces its chemical activity by the Arrhenius equation. This includes life processes such as metabolism. Cryonics could eventually provide long-term suspended animation.Tandy C (2014). The Prospect of Immortality − Fifty Years Later. Ria University Press, USA, {{ISBN|978-1-934297-21-6}}

Emergency Preservation and Resuscitation (EPR) is a way to slow the bodily processes that would lead to death in cases of severe injury.{{Cite web|last=Delbert|first=Caroline|date=2019-11-20|title=Doctors Place Humans in True Suspended Animation for First Time|url=https://www.popularmechanics.com/science/health/a29860656/first-human-trial-suspended-animation/|access-date=2020-09-29|website=Popular Mechanics|language=en-US}} This involves lowering the body's temperature below {{convert|34|C|F}}, which is the current standard for therapeutic hypothermia.

In June 2005, scientists at the University of Pittsburgh's Safar Center for Resuscitation Research announced they had managed to place dogs in suspended animation and bring them back to life, most of them without brain damage, by draining the blood out of the dogs' bodies and injecting a low temperature solution into their circulatory systems, which in turn keeps the bodies alive in stasis. After three hours of being clinically dead, the dogs' blood was returned to their circulatory systems, and the animals were revived by delivering an electric shock to their hearts. The heart started pumping the blood around the body, and the dogs were brought back to life.{{cite news| url=https://www.nytimes.com/2005/12/11/magazine/11ideas_section4-21.html | work=The New York Times | first=Stephen | last=Mihm | title=Zombie Dogs | date=11 December 2005}}

On 20 January 2006, doctors from the Massachusetts General Hospital in Boston announced they had placed pigs in suspended animation with a similar technique. The pigs were anaesthetized and major blood loss was induced, along with simulated - via scalpel - severe injuries (e.g. a punctured aorta as might happen in a car accident or shooting). After the pigs lost about half their blood the remaining blood was replaced with a chilled saline solution. As the body temperature reached {{convert|10|°C}} the damaged blood vessels were repaired and the blood was returned.{{cite journal|title=Does the rate of rewarming from profound hypothermic arrest influence the outcome in a swine model of lethal hemorrhage?|vauthors=Alam HB, Rhee P, Honma K, Chen H, Ayuste EC, Lin T, Toruno K, Mehrani T, Engel C, Chen Z |year=2006|issue=1|pmid=16456447 |doi=10.1097/01.ta.0000198469.95292.ec |volume=60 |journal=J Trauma |pages=134–146}} The method was tested 200 times with a 90% success rate.{{cite news|url=http://www.smh.com.au/articles/2006/01/20/1137553739997.html|title=Doctors claim suspended animation success|newspaper=The Sydney Morning Herald|date=20 January 2006|access-date=10 October 2006}}

The laboratory of Mark Roth at the Fred Hutchinson Cancer Research Center and institutes such as Suspended Animation, Inc are trying to implement suspended animation as a medical procedure which involves the therapeutic induction to a complete and temporary systemic ischemia, directed to obtain a state of tolerance for the protection-preservation of the entire organism, this during a circulatory collapse "only by a limited period of one hour". The purpose is to avoid a serious injury, risk of brain damage or death, until the patient reaches specialized attention.{{cite journal| title=Suspended animation for delayed resuscitation. Crit Care Med. 1996 Feb;24(2 Suppl):S24-47|journal=Critical Care Medicine|volume=24|issue=2 Suppl|pages=S24–47|pmid = 8608704|year = 1996|last1 = Bellamy|first1 = R|last2=Safar|first2=P|last3=Tisherman|first3=S. A|last4=Basford|first4=R|last5=Bruttig|first5=S. P|last6=Capone|first6=A|last7=Dubick|first7=M. A|last8=Ernster|first8=L|last9=Hattler Jr|first9=B. G|last10=Hochachka|first10=P|last11=Klain|first11=M|last12=Kochanek|first12=P. M|last13=Kofke|first13=W. A|last14=Lancaster|first14=J. R|last15=McGowan Jr|first15=F. X|last16=Oeltgen|first16=P. R|last17=Severinghaus|first17=J. W|last18=Taylor|first18=M. J|last19=Zar|first19=H|doi=10.1097/00003246-199602000-00046}}

{{col div|colwidth=30em}}

• Brain death
• Coma
• Cryptobiosis
• Immortality
• Life extension
• Stasis
• Suspended animation in fiction
• Technological utopianism

{{div col end}}

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{{Cryonics}}

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Category:Cryonics

Category:Senescence