Brain death in perspective.

Advances in lifesaving medical therapy over the past two decades have forced us to redefine death. Cessation of the heartbeat cannot be synonymous with death if the heart can be permanently removed and replaced with a plastic pump. We now can substitute for the function of all organs in the body, save one--the brain. When brain function is irreversibly lost, the person served by that brain has ceased to exist as a person and is medically and legally dead. This article focuses on the criteria currently used to diagnose irreversible brain failure.