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Brain stem death is a clinical syndrome defined by the absence of reflexes with pathways through the brain stem - the “stalk” of the brain, which connects the spinal cord to the mid-brain, cerebellum and cerebral hemispheres - in a deeply comatose, ventilator-dependent patient. Identification of this state carries a very grave prognosis for survival; cessation of heartbeat often occurs within a few days although it may continue for weeks or even months if intensive support is maintained.〔A Code of Practice for the Diagnosis and Confirmation of Death. Academy of Medical Royal Colleges, 70 Wimpole Street, London, 2008〕 In the United Kingdom, the formal diagnosis of brain stem death by the procedure laid down in the official Code of Practice〔 permits the diagnosis and certification of death on the premise that a person is dead when consciousness and the ability to breathe are permanently lost, regardless of continuing life in the body and parts of the brain, and that death of the brain stem alone is sufficient to produce this state.〔Criteria for the diagnosis of brain stem death. J Roy Coll Physns of London 1995;29:381-2〕 This concept of brain stem death is also accepted as grounds for pronoucing death for legal purposes in India〔The Transplantation of Human Organs Act, 1994. Act No.42 of 1994. s. 2〕 and Trinidad & Tobago.〔Human Tissue Transplant Act 2000. s. 19(1)〕 Elsewhere in the world the concept upon which the certification of death on neurological grounds is based is that of permanent cessation of all function in all parts of the brain - whole brain death - with which the reductionist United Kingdom concept should not be confused. The United States' President's Council on Bioethics made it clear, in its White Paper of December 2008, that the United Kingdom concept and clinical criteria are not considered sufficient for the diagnosis of death in the United States of America.〔Controversies in the determination of death. A White Paper by the President's Council on Bioethics, Washington, DC. p 66〕 ==Evolution of diagnostic criteria== The United Kingdom (UK) criteria were first published by the Conference of Medical Royal Colleges (with advice from the Transplant Advisory Panel) in 1976, as prognostic guidelines.〔Conference of Medical Royal Colleges and their Faculties in the UK. BMJ 1976;2:1187-8〕 They were drafted in response to a perceived need for guidance in the management of deeply comatose patients with severe brain damage who were being kept alive by mechanical ventilators but showing no signs of recovery. The Conference sought “to establish diagnostic criteria of such rigour that on their fulfilment the mechanical ventilator can be switched off, in the secure knowledge that there is no possible chance of recovery”. The published criteria – negative responses to bedside tests of some reflexes with pathways through the brain stem and a specified challenge to the brain stem respiratory centre, with caveats about exclusion of endocrine influences, metabolic factors and drug effects – were held to be “sufficient to distinguish between those patients who retain the functional capacity to have a chance of even partial recovery and those where no such possibility exists”. Recognition of that state required the withdrawal of fruitless further artificial support so that death might be allowed to occur, thus “sparing relatives from the further emotional trauma of sterile hope”.〔 In 1979, the Conference of Medical Royal Colleges promulgated its conclusion that identification of the state defined by those same criteria – then thought sufficient for a diagnosis of brain death – “means that the patient is dead” 〔Conference of Medical Royal Colleges and their Faculties in the UK. BMJ 1979;1:332.〕 Death certification on those criteria has continued in the United Kingdom (where there is no statutory legal definition of death) since that time, particularly for organ transplantation purposes, although the conceptual basis for that use has changed. In 1995, after a review by a Working Group of the Royal College of Physicians of London, the Conference of Medical Royal Colleges 〔 formally adopted the “more correct” term for the syndrome, "brain stem death" - championed by Pallis in a set of 1982 articles in the British Medical Journal 〔Pallis,C. From Brain Death to Brain Stem Death, BMJ, 285, November 1982〕 – and advanced a new definition of human death as the basis for equating this syndrome with the death of the person. The suggested new definition of death was the “irreversible loss of the capacity for consciousness, combined with irreversible loss of the capacity to breathe”. It was stated that the irreversible cessation of brain stem function will produce this state and “therefore brain stem death is equivalent to the death of the individual”.〔 抄文引用元・出典: フリー百科事典『 ウィキペディア（Wikipedia）』 ■ウィキペディアで「brain stem death」の詳細全文を読む スポンサード リンク
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