Bench-to-bedside review: When is dead really dead – on the legitimacy of using neurologic criteria to determine death

Abstract

This review explores the legitimacy of the whole brain death (WBD) criterion. I argue that it does not fulfill the traditional biologic definition of death and is, therefore, an unsound clinical and philosophical criterion for death. I dispute whether the clinical tests used to diagnose WBD are sufficient to prove all critical brain functions have ceased, as well as examine the sets of brain functions that persist in many WBD patients. I conclude that the definition of death must be modified from a biologic to an ontologic model if we intend to maintain the WBD criterion. IntroductionDetermining death using neurologic criteria, generally referred to as 'brain death', has been accepted for decades in most developed countries. Despite its ubiquity, however, the legitimacy of the whole brain death (WBD) criterion continues to be challenged on clinical and conceptual grounds. A primary reason for this is that brain dead individuals are at odds with our traditional intuition about death. Otherwise stated, the brain dead do not look dead; they are pink and warm and often perform tasks that corpses cannot. This begs the fundamental question, are patients who are declared brain dead really dead?In this review I argue that, in its current usage, WBD is a theoretically inconsistent criterion, and that its main premise, that a functioning brain is required for integrative life, is flawed. I provide evidence that the bodies of WBD patients continue to integrate at the level of the organism as a whole and therefore fail to satisfy the classic definition of death. If ability to maintain integrated functioning is what distinguishes life from death, as the current definition of death holds, then I argue that a dead brain does not stop such functions from continuing. I conclude the review by arguing for a modification to the definition of death itself, in which the brain dead are dead, but not on the merits of the traditional biologic justification. Spontaneous life versus assisted lifeThe brain dead present a peculiar problem in that they are breathing corpses, which the President's Commission Report [1] attempted to explain as follows: 'When an individual's breathing and circulation lack neurologic integration, he or she is dead." The President's Commission established that artificially maintained respiration and circulation in a WBD patient are irrelevant because they are controlled by mechanical intervention rather than by the brain. They conceded that although it may look as if the patient is alive, in fact the body is not functioning in any integrated manner because it is being manipulated externally. Accordingly, they argue, 'the function and results are similar, but the source, cause, and purpose are different between those individuals with and those without functioning brains.'We immediately encounter problems if we determine life from death based on technology if we consider that a person is not any less alive if he requires an artificial intervention. By its very definition, life-sustaining treatment serves to...

Morte encefálica: uma discussão encerrada?

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Donation after cardiac death: a survey of university student opinions on death and donation

“…These surveys did not communicate that the ethical concern of when to declare a person dead, with irreversible cessation of circulation, is central to the DCD debate. There is a significant difference between asking if organs can be donated after death, and asking when death has occurred [10][11][12][13][14][15]. A recent analysis of 60 organ procurement organizations' Internet enrollment for organ donation websites found that no consent form disclosed cardiac death criteria or organ procurement timing after cardiac death [28].…”

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Ethical controversies at end of life after traumatic brain injury: Defining death and organ donation

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