Brain death


Brain death

Brain death is a legal definition of death that emerged in the 1960s as a response to the ability to resuscitate individuals and mechanically keep the heart and lungs working. In simple terms, brain death is the irreversible end of all brain activity (including involuntary activity necessary to sustain life) due to total necrosis of the cerebral neurons following loss of blood flow and oxygenation. It should not be confused with a persistent vegetative state.

Legal history

Traditionally, both the legal and medical communities determined death through the end of certain bodily functions, especially respiration and heartbeat. With the increasing ability of the medical community to resuscitate people with no heart beat, respiration or other signs of life, the need for a better definition of death became obvious. This need gained greater urgency with the widespread use of life support equipment, which can maintain body functions indefinitely, as well as rising capabilities and demand for organ transplantation.

In the U.S., an "ad hoc" committee at Harvard Medical School published a pivotal 1968 report to define irreversible coma. The Harvard criteria gradually gained consensus toward what is now known as brain death. In the wake of the 1976 Karen Ann Quinlan controversy, state legislatures moved to accept brain death as an acceptable indication of death. Finally, a presidential commission issued a landmark 1981 report — [http://www.bioethics.gov/reports/past_commissions/defining_death.pdf "Defin­ing Death: Medical, Legal, and Ethical Issues in the Determination of Death."] — that rejected the "higher brain" approach to death in favor of a "whole brain" definition. This report was the basis for the Uniform Determination of Death Act, which is now the law in almost all fifty states.

Today, both the legal and medical communities use "brain death" as a legal definition of death. Using brain-death criteria, the medical community can declare a person legally dead even if life support equipment keeps the body's metabolic processes working. The first nation to adopt brain death as a legal definition of death was Finland in 1971. In the United States, Kansas enacted a similar law earlier. [cite journal | author=(Randell T. | title=Medical and legal considerations of brain death | journal=Acta Anaesthesiologica Scandinavica | volume=48 | issue=2 | year=2004 | pages=139–144 | pmid=14995934 | doi=10.1111/j.0001-5172.2004.00304.x]

Religion

Despite the adoption of whole brain criteria in the United States and "brainstem" criteria in the United Kingdom, there has been opposition to brain death criteria from the beginning. Traditionalist Orthodox Jews have staunchly defended the traditional conception of death in the U.S. and Israel.cite book
last = Bleich
first = J. David
authorlink = J. David Bleich
title = Time of death in Jewish law
publisher = Z. Berman
date = 1991
] Conversely, some modern Orthodox rabbis and Israel's Chief Rabbinate have adopted determinations of death based on brain function.See Moshe Tendler's elucidation of Rabbi Moshe Feinstein's responsa] As a result, Orthodox Jewish ethics has been sharply divided over key death-related policies. Tactically, Orthodox Jewish opponents to brain death have requested waivers from state law, as a matter of religious freedom, so as to continue relying on traditional indicia. Meanwhile, proponents such as [http://www.hods.org Halichic Organic Donor Society] have been active in advocating organ donations and transplants.

Similarly, Islamic views on brain death are mixed. [cite journal
title = Views of Muslim scholars on organ donation and brain death
journal = Transplantation Proceedings
volume = 29
issue = 8
pages = 3217
date = December 1997
doi = 10.1016/S0041-1345(97)00876-2
author = Al-Mousawi, M
] [cite journal
last = Khan
first = Faroque
title = The Definition of Death in Islam: Can Brain Death Be Used as A Criteria of Death in Islam?
journal = Fordham Urban Law Journal
volume = 30
date = 2002
accessdate = 2008-05-03
] [cite book
last = Moazam
first = Farhat
title = Bioethics and Organ Transplantation in a Muslim Society: A Study in Culture, Ethnography, and Religion
publisher = Indiana University Press
date = September 2006
pages = 32ff
isbn = 978-0253347824
]

The 1981 federal report, "Defin­ing Death", found that Catholic and Protestant theologies did not object to brain death criteria. Indeed, Dennis Horan, president of the pro-life group Americans United for Life, stated:

Legislation limiting the concept of brain death to the irreversible cessation of total function of the brain, including the brain stem, is beneficial and does not undermine any of the values we seek to support.

More recently, the findings of the 1981 President's Commission Report have been questioned. [cite book
last = Potts
first = M
last2 = Byrne
first2 = PA
last3 = Nilges
first3 = RG
title = Beyond Brain Death: The Case Against Brain-Based Criteria for Human Death
publisher = Kluwer Academic Publishers
date = September 2000
location = Dordrecht, The Netherlands
isbn = 0306468824
] The new attack on brain death criteria has been multi-pronged. First, the view that brain death marks the end of the integrated unity of the human organism has been questioned. Alan Shewmon has argued that the body as a whole is the central integrator of the organism rather than the brain. [cite journal
last = Shewmon
first = D. Alan
title = Chronic 'brain death': Meta-analysis and conceptual consequences
journal = Neurology
volume = 51
pages = 1538–1545
date = 1998
url = http://www.neurology.org/cgi/content/abstract/51/6/1538
accessdate = 2008-05-03
pmid = 9855499
] He appeals to, among other reasons, brain dead pregnant women who have lived up to 200+ days and given birth to healthy children, as well as to a brain dead boy who lived over fourteen years on a ventilator and with basic nursing support. Others have argued that there is insufficient evidence that the entire brain is dead in a brain dead individual.de Mattei, R., ed. Finis Vitae: Is Brain Death Still Life? 2006, Consiglio Nazionale delle Rescherche, Rome.] Some brain dead individuals have continuing EEG activity [cite journal
last = Young
first = Bryan
last2 = Shemie
first2 = Sam
last3 = Doig
first3 = Christopher
last4 = Teitelbaum
first4 = Jeannie
title = Brief review: The role of ancillary tests in the neurological determination of death
journal = Canadian Journal of Anesthesia
volume = 53
pages = 620–627
date = 2006
url = http://www.cja-jca.org/cgi/content/abstract/53/6/620
accessdate = 2008-05-03
pmid = 16738299
] and others maintain normal or near-normal body temperature, implying continuing hypothalamic function. [cite journal
last = Shewmon
first = D. Alan
title = The Brain and Somatic Integration: Insights Into the Standard Biological Rationale for Equating Brain Death With Death
journal = The Journal of Medicine and Philosophy
volume = 26
issue = 5
pages = 457–478
publisher = Routledge, part of the Taylor & Francis Group
date = October 2001
url =
doi = 10.1076/jmep.26.5.457.3000
accessdate = 2008-05-03
]

In Catholic medical ethics, Pope Pius XII stated that death is determined by medical experts and it "does not fall within the competence of the Church." ["The Prolongation of Life" in "The Pope Speaks" 4:4 1958] Advocates of brain death criteria have claimed that this implies that the church is bound to support the view of the medical community on this issue. More recently, the Pontifical Academy of Science has upheld Catholic doctrine. ["The determination of brain death and its relationship to human death." Working Group, 10-14 December 1989, pp. xxvii-210 [http://www.vatican.va/roman_curia/pontifical_academies/acdscien/own/documents/rc_acdsci_doc_190999_publications_it.html] [http://www.owensborodio.org/archives/newspaper/2000/5organ.html] ] Nevertheless, there was some Catholic dissent on neurological criteria for death. [ [http://initiative-kao.de/KAO-Braindeath_is_not_death.htm Brain death is not death] ] In addition, a volume consisting of essays by opponents of brain death criteria who participated in a 2005 conference at the Pontifical Academy of Sciences was published in 2006 by a publisher outside the Vatican.

In 2008, an article of the Osservatore Romano expressed the wish that the debate on brain death be re-opend because of new developments in the medical world. Anyway, Vatican spokesman said that the article presented a personal opinion of the author and "did not reflect a change in the Catholic Church's position". [ [Vatican newspaper says new questions raised about brain death http://www.catholicnews.com/data/stories/cns/0804460.htm] ]

Medical criteria

A brain-dead individual has no clinical evidence of brain function upon physical examination. This includes no response to pain and no cranial nerve reflexes. Reflexes include pupillary response (fixed pupils), oculocephalic reflex, corneal reflex, no response to the caloric reflex test and no spontaneous respirations.

It is important to distinguish between brain death and states that may mimic brain death (e.g., barbiturate intoxication, alcohol intoxication, sedative overdose, hypothermia, hypoglycemia, coma or chronic vegetative states). Some comatose patients can recover, and some patients with severe irreversible neurologic dysfunction will nonetheless retain some lower brain functions such as spontaneous respiration, despite the losses of both cortex and brainstem functionality. Thus, anencephaly, in which there is no higher brain present, is generally not considered brain death, though it is certainly an irreversible condition in which it may be appropriate to withdraw life support.

Note that brain electrical activity can stop completely, or drop to such a low level as to be undetectable with most equipment. This includes a "flat EEG" during deep anaesthesia or cardiac arrest. However, the EEG is not required in the United States, but is considered to have confirmatory value.

The diagnosis of brain death needs to be rigorous to determine whether the condition is irreversible. Legal criteria vary, but it generally requires neurological exams by two independent physicians. The exams must show complete absence of brain function, and may include two isoelectric (flat-line) EEGs 24 hours apart. The widely-adopted Uniform Determination of Death Act in the United States attempts to standardize criteria. The patient should have a normal temperature and be free of drugs that can suppress brain activity if the diagnosis is to be made on EEG criteria.

Alternatively, a radionuclide cerebral blood flow scan that shows complete absence of intracranial blood flow can be used to confirm the diagnosis without performing EEGs.

Consciousness

It is presumed that a permanent cessation of electrical activity indicates the end of consciousness. Those who view the neo-cortex of the brain as solely responsible for consciousness, however, argue that electrical activity there should be the only consideration when defining death. In many cases, especially when elevated intracranial pressure prevents blood flow into the brain, the entire brain is nonfunctional; however, some injuries may affect only the neo-cortex. The case of Zach Dunlap, in which a man was declared brain dead but later recovered and remembers the doctors pronouncing him dead, [ [http://www.news.com.au/heraldsun/story/0,21985,23427539-23109,00.html Dead man says he feels pretty good] ] questions this presumption. However, since he was declared dead only a few hours after presentation, he did not yet meet the American Academy of Neurology's brain death criteria. [ [http://www.aan.com/professionals/practice/guidelines/pda/Brain_death_adults.pdf Determining Brain Death in Adults] ] While Dunlap was being disconnected from life support four hours after the pronouncement, one of his cousins, Dan Coffin, who is also a nurse, found he was responsive to pain, demonstrating that he was alive, [ [http://today.msnbc.msn.com/id/23775873/ Pronounced dead, man takes ‘miraculous’ turn] ] so this example is questionable.

Organ donation

Most organ donation for organ transplantation is done in the setting of brain death.In some nations (for instance, Belgium, Poland, Portugal and France) everyone is automatically an organ donor, although some jurisdictions (such as Singapore) allow opting out of the system. Elsewhere, consent from family members or next-of-kin is required for organ donation. The non-living donor is kept on ventilator support until the organs have been surgically removed. If a brain-dead individual is not an organ donor, ventilator and drug support is discontinued and cardiac death is allowed to occur.

ee also

* Brain stem death
* Clinical death
* Death
* Persistent vegetative state

References

*Lock M. Twice Dead: Organ Transplants and the Reinvention of Death. 2002, University of California Press, Berkeley, CA.
* Howsepian AA. In defense of whole-brain definitions of death. "Linacre Quarterly". 1998 Nov;65(4):39-61. PMID 12199254
* Karasawa H, "et al." Intracranial electroencephalographic changes in deep anesthesia. "Clin Neurophysiol." 2001 Jan;112(1):25-30. PMID 11137657

External links

* [http://theresurrector.com Informational Portal about Brain Death]
* [http://www.deathreference.com/Bl-Ce/Brain-Death.html Brain Death] from the Encyclopedia of Death and Dying
* [http://health.howstuffworks.com/brain-death.htm How Stuff Works - Brain Death]
* [http://www.qcc.cuny.edu/socialsciences/ppecorino/DeathandDying_TEXT/Bernat_Culver_Gert.htm Textbook section]
* [http://legalwikipro.com/wiki/index.php?title=Death_(OK) LegalWikiPro Article on Brain Death, Organ Donation and Civil Action for Mishandling of Dead Body under Oklahoma law]


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Look at other dictionaries:

  • brain death — brain dead /brayn ded /, adj. brain dead. complete cessation of brain function as evidenced by absence of brain wave activity on an electroencephalogram: sometimes used as a legal definition of death. [1965 70] * * * State of irreversible… …   Universalium

  • brain death — / brān ˌdeth/ n: the final stopping of activity in the central nervous system esp. as indicated by a flat electroencephalogram for a usu. statutorily predetermined period of time brain–dead / brān ˌded/ adj Merriam Webster’s Dictionary of Law.… …   Law dictionary

  • brain death — n final cessation of activity in the central nervous system esp. as indicated by a flat electroencephalogram for a predetermined length of time brain dead adj * * * see death * * * irreversible brain damage as manifested by absolute… …   Medical dictionary

  • brain death — brain′ death n. med pat complete cessation of brain function as evidenced by absence of brain wave activity on an electroencephalogram: sometimes used as a legal definition of death • Etymology: 1965–70 …   From formal English to slang

  • brain death — n. a condition in which all vital functions of the brain are determined to have irreversibly ceased: variously accepted as a legal concept of death …   English World dictionary

  • brain death — brain ,death noun uncount a state in which someone s brain has stopped working, so that they are in fact dead, even though a machine may continue to make their heart work …   Usage of the words and phrases in modern English

  • brain death — ► NOUN ▪ irreversible brain damage causing the end of independent breathing …   English terms dictionary

  • brain death — noun death when respiration and other reflexes are absent; consciousness is gone; organs can be removed for transplantation before the heartbeat stops • Syn: ↑cerebral death • Hypernyms: ↑death * * * noun : final cessation of activity in the… …   Useful english dictionary

  • brain death — Numerous states have enacted statutory definitions of death which include brain related criteria. For example, many states have adopted the Uniform Determination of Death Act. See death. Characteristics of brain death consist of: (1)… …   Black's law dictionary


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