DECLARATION OF BRAIN DEATH

Abstract

SUMMARY It is hard to conceive of a clinical diagnosis more important than the diagnosis of death. Once thought to be a rather simple proposition (“death means breathing and heart beat have stopped”), modern technology has required a reassessment of the definition. Over the past 30 years, a brain-centered rather than a cardiorespiratory-centered definition of death has emerged and now has achieved wide acceptance in medical, legal, ethical and religious circles. Several formal sets of criteria have been published, not so much to define rigidly the diagnosis of brain death, but to provide the medical community with carefully formulated procedures that help establish the standard of care. Such a broadly accepted standard of care supports the clinician's judgment in declaring a patient brain dead and helps reassure the broader community that both the concept and diagnosis of brain death reflect a consensus among medical, legal, and ethical experts. The criteria most commonly applied in the United States today are those generated by the President's Commission. Other criteria are chiefly of historical importance only. Although there is broad consensus, some differences are seen within the medical community. The British definition of brain death, for instance, equates brain stem death with brain death. Theoretically, this could lead to some patients being declared brain dead in Britain who would not fulfill American criteria; however, it is unlikely that there is any difference in ultimate outcome in the two countries. Within the American medical community, there is some debate over the “whole-brain” definition of brain death. Strictly speaking, this definition, espoused by the President's Commission, would not allow even minimal brain function, such as preserved hypothalamic function. Alternatives discussed in the literature include the “higher brain” definition or the concept that brain death is the loss of functioning of the organism as a whole. In spite of these controversies over conceptual details of the definition, the concept of brain death has stood up to challenge within the legal and ethical communities as well as within medicine, and is now an established part of medical practice.