Category: Critical Care
Keywords: Apnea test, brain death, brain stem death, coma, death, cardiopulmonary death (PubMed Search)
Brain death is the permanent absence of cerebral and brainstem functions (coma, absent pupillary reflexes, no spontaneous respiration, etc.). Legally, brain death is equivalent to cardiopulmonary death.
If brain death is suspected, confirmation is necessary. The apnea test is most commonly used, evaluating for spontaneous breaths when disconnected from the ventilator. If apnea testing is not possible (e.g., ambiguous clinical exam or cardiopulmonary instability) ancillary testing is needed:
Wijdicks EF, The diagnosis of brain death. N Engl J Med. 2001 Apr 19;344(16):1215-21.