Justified use of painful stimuli in the coma examination: a neurologic and ethical rationale.

Much has been written about the neurologic basis and rationale for the coma examination, but little has been written about its ethical framework. In contrast to the neurologic framework, the ethical basis for the use of painful stimuli in the coma examination is context dependent and value driven, aimed at identifying the ethical justification for healthcare professionals to cause pain for patients in ways that would not be tolerated or justifiable in any other setting. Basic ethical principles can be used to justify the use of painful stimuli to examine patients, but they also impose limits on their use. To clarify the ethical issues that apply to the coma examination, we review its neurologic and ethical bases and propose a practical test by which to justify the use of painful stimuli.