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Published on: November 18, 2018
How Harvard Defined Irreversible Coma
1Division of Critical Care Neurology, Mayo Clinic, 200 First Street SW, Rochester, MN, 55905, USA. wijde@mayo.edu.
Abstract:
The Harvard criteria for the definition of irreversible coma or brain death were a product of a multidisciplinary committee chaired by anesthesiologist Beecher. The Harvard criteria included unreceptivity, unresponsiveness, no movements or breathing, no reflexes with further delineation of brainstem reflexes, and a flat electroencephalogram (repeated after 24 h with no change). The apnea test involved disconnection of the ventilator for 3 min. Hypothermia or any other central nervous system depressant had to be excluded. The Harvard criteria (and what followed) have been a bane for bioethicists from day one. This historical vignette explains, criticizes, and celebrates this landmark publication for its courage to tackle the topic. The Harvard criteria resulted in more studies and more criteria gradually complicating matters until the American Academy of Neurology in 1995 provided the necessary simplicity.
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