Determining Brain Death: Basic Approach and Controversial Issues

Between 15% and 30% of patients admitted to intensive care units are comatose at some point during their admission as a result of primary neurologic (trauma, stroke, meningitis, neoplasm, seizures) or systemic (cardiopulmonary arrest, toxins, sepsis, metabolic derangements) problems.¹  Comatose patients have grossly impaired brain function that renders them unconscious. Although some comatose patients recover, others reacquire minimal environmental awareness (a minimally conscious state), transition to being in a vegetative state, or progress to death.²  Patients who become vegetative have a complete lack of awareness of themselves and their environment, but have sleep-wake cycles and variable preservation of cranial nerve function. After a month of being vegetative, a patient is described as being in a persistent vegetative state, and if there is a high degree of clinical certainty that the condition is irreversible, the patient is deemed to be in a permanent vegetative state.³  Patients who are...