Cardiopulmonary arrest is a test of the brain's tolerance to global ischemia. New insights into the pathophysiology of global ischemia have led to the potential use of early prophylactic anticonvulsants, hypothermia, barbiturate coma, glucose manipulations, calcium-blocking agents, and hemodilution. A wide spectrum of neurologic sequelae may follow global ischemia, ranging from brain death, vegetative states, and impairment of higher intellectual function to syndromes of amnesia and cortical blindness, post-anoxic myoclonus, delayed leukoencephalopathy, and spinal stroke. The distinctive features of these sequelae and their pathophysiologic aspects are discussed. Special attention is given to brain death and prognostication.