Brain death

Brain death is the complete loss of brain function (including involuntary activity necessary to sustain life).It differs from persistent vegetative state, in which the person is alive and some autonomic functions remain.
Brain death denotes irreversible conditions, i.e., perfect loss of brain and its stem functions while signs of life still exist in patients. Studies indicated that 1%–4% of deaths occur in hospitals, and 10% of mortalities in Intensive Care Units (ICUs) are reported because of brain death.