Practice parameters for determining brain death in adults

of the American Academy of Neurology Overview. Brain death is defined as the irreversible loss of function of the brain, including the brainstem. Brain death from primary neurologic disease usually is caused by severe head injury or aneurysmal subarachnoid hemorrhage. In medical and surgical intensive care units, however, hypoxic-ischemic brain insults and fulminant hepatic failure may result in irreversible loss of brain function. In large referral hospitals, neurologists make the diagnosis of brain death 25 to 30 times a year.