[Brain death, bioethics and organ transplantation].

The concept of death has evolved medically, legally and culturally since the introduction of life support technologies in the middle of the 20th century. The traditional cardiopulmonary and the new neurologically based brain death criterions of death are examined. We conclude that brain death, defined as total and irreversible loss of function of the whole brain, fulfills better "the permanent cessation of functioning of the organism as a whole" definition of death.