1) Brain death is the irreversible loss of all brain and brainstem functions and is diagnosed clinically through examination of coma, absent brainstem reflexes, and apnea on testing.
2) The role of the intensivist is to determine if the patient meets criteria for brain death through clinical examination and ancillary testing, and to prepare potential organ donors.
3) Brain death results from severe brain injury or lack of oxygen that causes raised intracranial pressure, cessation of cerebral blood flow, and ultimately complete necrosis of brain tissue.