Editing Human brain (section)

===Brain death===
{{Main|Brain death}}
Brain death refers to an irreversible total loss of brain function.<ref name="GOILA2009">{{cite journal |last1=Goila |first1=AK |last2=Pawar |first2=M |title=The diagnosis of brain death |journal=Indian Journal of Critical Care Medicine |date=2009 |volume=13 |issue=1 |pages=7–11 |doi=10.4103/0972-5229.53108|pmid=19881172 |pmc=2772257 |doi-access=free }}</ref><ref name=":0">{{Cite journal |last=Wijdicks |first=EFM |date=January 8, 2002 |title=Brain death worldwide: accepted fact but no global consensus in diagnostic criteria |journal=Neurology |volume=58 |issue=1 |pages=20–25 |pmid=11781400 |doi=10.1212/wnl.58.1.20|s2cid=219203458 }}</ref> This is characterised by [[coma]], loss of [[reflex]]es, and [[apnoea]],<ref name=GOILA2009/> however, the declaration of brain death varies geographically and is not always accepted.<ref name=":0" /> In some countries there is also a defined syndrome of [[brainstem death]].<ref>{{cite journal |last1=Dhanwate |first1=AD |title=Brainstem death: A comprehensive review in Indian perspective. |journal=Indian Journal of Critical Care Medicine |date=September 2014 |volume=18 |issue=9 |pages=596–605 |pmid=25249744 |doi=10.4103/0972-5229.140151 |pmc=4166875 |doi-access=free }}</ref> Declaration of brain death can have profound implications as the declaration, under the principle of [[Futile medical care|medical futility]], will be associated with the withdrawal of life support,{{sfn|Davidson's|2010|p=1158}} and as those with brain death often have organs suitable for [[organ donation]].<ref name=":0" />{{sfn|Davidson's|2010|p=200}} The process is often made more difficult by poor communication with patients' families.<ref name="Urden">{{cite book |last1=Urden |first1=L.D. |last2=Stacy |first2=K.M. |last3=Lough |first3=M.E. |title=Priorities in Critical Care Nursing – E-Book |publisher=[[Elsevier Health Sciences]] |isbn=978-0-323-29414-0 |pages=112–113 |year=2013 |url=https://books.google.com/books?id=lLvwAwAAQBAJ&pg=PA112}}</ref>

When brain death is suspected, reversible [[differential diagnosis|differential diagnoses]] such as, electrolyte, neurological and drug-related cognitive suppression need to be excluded.<ref name="GOILA2009" />{{sfn|Davidson's|2010|p=1158}} Testing for reflexes{{efn|Including the [[vestibulo-ocular reflex]], [[corneal reflex]], [[gag reflex]] and dilation of the pupils in response to light,{{sfn|Davidson's|2010|p=1158}}}} can be of help in the decision, as can the absence of response and breathing.{{sfn|Davidson's|2010|p=1158}} Clinical observations, including a total lack of responsiveness, a known diagnosis, and [[neural imaging]] evidence, may all play a role in the decision to pronounce brain death.<ref name="GOILA2009" />