Editing Coma (section)

{{Short description|State of unconsciousness}}
{{Distinguish|Comma}}
{{Other uses|Coma (disambiguation)|Comas (disambiguation)}}
{{Redirect|Comatose|other uses}}
{{pp-vandalism|small=yes}}
{{Infobox medical condition (new)
| name          = Coma
| field         = [[Neurology]], [[psychiatry]]
| symptoms      = Unconsciousness
| complications = [[Persistent vegetative state]], [[death]]
| duration      = Can vary from a few days to several years
| image         = Comaventilator.jpg
| caption       = Image of a comatose man unresponsive to stimuli
}}
A '''coma''' is a deep state of prolonged [[unconsciousness]] in which a person cannot be awakened, fails to [[Nociception|respond normally]] to [[Pain|painful stimuli]], light, or sound, lacks a normal [[Circadian rhythm|sleep-wake cycle]] and does not initiate [[voluntary action]]s.<ref name="RR">{{cite book |last1=Weyhenmeyer |first1=James A. |last2=Gallman |first2=Eve A. |title=Neuroscience |date=2007 |publisher=Mosby |isbn=978-0-323-02261-3 |pages=177–179 }}</ref> The person may experience respiratory and circulatory problems due to the body's inability to maintain normal bodily functions. People in a coma often require extensive medical care to maintain their health and prevent complications such as [[pneumonia]] or [[blood clots]].<ref name="Huff Tadi Coma">{{cite book |last1=Huff |first1=J. Stephen |last2=Tadi |first2=Prasanna |title=StatPearls |date=2024 |publisher=StatPearls Publishing |chapter-url=http://www.ncbi.nlm.nih.gov/books/NBK430722/ |chapter=Coma |pmid=28613473 }}</ref> Coma patients exhibit a complete absence of wakefulness and are unable to consciously feel, speak or move.<ref name=":0">{{cite journal |last1=Bordini |first1=Ana Luisa |last2=Luiz |first2=Thiago F. |last3=Fernandes |first3=Maurício |last4=Arruda |first4=Walter O. |last5=Teive |first5=Hélio A.G. |title=Coma scales: a historical review |journal=Arquivos de Neuro-Psiquiatria |date=December 2010 |volume=68 |issue=6 |pages=930–937 |doi=10.1590/S0004-282X2010000600019 |pmid=21243255 |doi-access=free }}</ref><ref>{{cite journal |last1=Cooksley |first1=Tim |last2=Holland |first2=Mark |title=The management of coma |journal=Medicine |date=February 2017 |volume=45 |issue=2 |pages=115–119 |doi=10.1016/j.mpmed.2016.12.001 }}</ref> Comas can be the result of natural causes, or can be [[Induced coma|medically induced]], for example, during [[General anaesthesia|general anesthesia]].<ref>{{Cite web |author1=Marc Lallanilla |date=2013-09-06 |title=What Is a Medically Induced Coma? |url=https://www.livescience.com/39483-what-is-a-medically-induced-coma.html |access-date=2022-04-23 |website=livescience.com |language=en}}</ref>

Clinically, a coma can be defined as the consistent inability to follow a one-step command.<ref>{{Cite web|url=https://www.glasgowcomascale.org/|title=The Glasgow structured approach to assessment of the Glasgow Coma Scale|website=www.glasgowcomascale.org|access-date=2019-03-06}}</ref><ref>{{cite book |doi=10.1016/B978-1-4160-3206-9.10059-X |chapter=Coma |title=Critical Care Secrets |date=2007 |last1=Bonovich |first1=David C. |pages=381–384 |isbn=978-1-4160-3206-9 }}</ref> For a patient to maintain consciousness, the components of ''wakefulness'' and ''awareness'' must be maintained. [[Wakefulness]] is a quantitative assessment of the degree of [[consciousness]], whereas [[awareness]] is a qualitative assessment of the functions mediated by the [[cerebral cortex]], including cognitive abilities such as attention, sensory perception, explicit memory, language, the [[Executive functions|execution of tasks]], temporal and spatial orientation and reality judgment.<ref name=":0" /><ref>{{cite book |doi=10.1016/B978-008045046-9.01770-8 |chapter=Coma |title=Encyclopedia of Neuroscience |date=2009 |last1=Laureys |first1=S. |last2=Boly |first2=M. |last3=Moonen |first3=G. |last4=Maquet |first4=P. |pages=1133–1142 |isbn=978-0-08-045046-9 }}</ref> [[Neuroscience|Neurologically]], consciousness is maintained by the activation of the cerebral cortex—the [[gray matter]] that forms the brain's outermost layer—and by the [[reticular activating system]] (RAS), a structure in the [[brainstem]].<ref name=med>{{cite book |author=Hannaman, Robert A.|title=MedStudy Internal Medicine Review Core Curriculum: Neurology 11th Ed|publisher=MedStudy| year=2005 |pages=(11–1) to (11–2) |isbn=1-932703-01-2}}</ref><ref>{{cite news |title=Persistent vegetative state: A medical minefield |url=https://www.newscientist.com/article/mg19526111-800-persistent-vegetative-state-a-medical-minefield/ |work=New Scientist |date=4 July 2007 }}</ref>