<prompt> Brain death is defined as loss of: March 2005Withdrawl reflexBrain stem functionsCoical functionsSpinal reflex  <response>: Ans. B: Brain stem functions Brain death should be suspected in any patient rendered deeply comatose and apneic from a profound or diffuse brain insult. The cardinal diagnostic criteria for brain death are: 1 profound coma with total unresponsiveness, 2 apnea despite induced hypercapnia, 3 absence of all reflexes subserved by the brainstem and cranial nerves, 4 presence of a structural brain lesion sufficient to produce the clinical findings, and 5 irreversibility Areflexia of those reflexes subserved by the cranial nerves must be present for brain death to be determined. There can be no pupillary light reflexes, vestibulo-ocular reflexes, corneal reflexes, gag reflexes, or cough reflexes. 