Traditionally the cessation of breathing and heart beat has marked the passage from life to death. Shortly after death was determined, the body became a cold corpse, suitable for burial or cremation. Two technological changes in the second half of the twentieth century prompted calls for a new, or at least expanded, definition of death: the development of intensive care medicine, especially the use of mechanical ventilators, and the advent of successful transplantation of vital organs. Patients with profound neurological damage, leaving them incapable of breathing on their own and in an irreversible coma, could be maintained for some period of time with the aid of mechanical ventilation. The situation of these patients posed two ethical questions. Is it appropriate to stop life-sustaining treatment? If so, is it acceptable to retrieve vital organs for transplantation to save the lives of others before stopping treatment?
In 1968, the Ad Hoc Committee of the Harvard Medical School to Examine the Definition of Brain Death proposed that death could be determined on the basis of neurological criteria, thus providing a positive answer to these two questions (Ad Hoc Committee 1968). According to the position of this committee, patients diagnosed with the cessation of brain function are dead, despite the fact that they breathe and circulate blood with the aid of mechanical ventilation. [End Page 185] Because they are dead, it is appropriate, indeed imperative, to stop mechanical ventilation. And because they are dead, it becomes ethical to procure vital organs for transplantation before stopping what otherwise would be life-sustaining treatment. Remarkably, this innovative neurological determination of death became, with little debate or controversy, the established position in medical ethics and the law throughout the United States.
The Harvard Committee articulated the diagnosis of “irreversible coma,” but merely asserted that this condition constituted death. No explanatory rationale was provided. It fell to the President’s Commission for the Study of Ethical Problems in Medicine and Biomedical and Behavioral Research to provide an authoritative rationale in its 1981 report, Defining Death. The second paragraph of the report set the stage as follows: “The question addressed here is not inherently difficult or complicated. Simply, it is whether the law ought to recognize new means for establishing that the death of a human being has occurred” (President’s Commission 1981, p. 3). The Commission claimed that “death is a unitary phenomenon” (p. 7) and that the determination of death by neurological criteria, in terms of the absence of all brain function, is consistent with the traditional conception of death as the cessation of vital functioning of the organism as a whole. The key issue is the integrative functioning of the human organism, which ceases to exist, according to the Commission, when the whole brain, including higher cortical areas and the brain stem, fails to function. Although “brain-dead” patients do not appear to be dead—i.e., the reality of their death is “masked” by the activity of mechanical ventilation—the patient’s body has irreversibly lost all capacity for integrative functioning. In the words of the Commission: “When artificial means of support mask this loss of integration as measured by the old methods [cessation of respiration and heart beat], brain-oriented criteria and tests provide a new window on the same phenomenon” (p. 33). The President’s Commission was instrumental in developing and establishing “The Uniform Definition of Death Act”: “An individual who has sustained either (1) irreversible cessation of circulatory and respiratory functions, or (2) irreversible cessation of all functions of the entire brain, including the brain stem, is dead” (p. 2).
Although the question posed by the President’s Commission was easy to articulate, the answer, over time, has proved complicated and controversial. The coherence and cogency of determining death by neurological criteria has been challenged. Various experts have demonstrated that “brain-dead” patients maintained on mechanical ventilation display a range of vital, integrative, functioning, which conflicts with the judgment that they are dead (Truog and...