The traditional cardiovascular clinical signs should be retained. There are a whole series of tests that must be performed and repeated more than once. Controversy regarding the specific signs that indicate brain death Most often they include response to pain, cerebral function, brain-stem reflexes and apnea tests. The Controversy surrounding brain death. Some argue that neuronal activity is insufficient for determining brain death.
Tests exist, however, that can measure the blood flow in the brain.
If blood no longer circulates then the brain is considered dead. This leaves the medical definition of death to those who should define it-medical experts.