Traditionally, death is recognised by permanent stoppage of the heart and respiration. Until few decades ago this had served well in all situations. However medical knowledge has advanced, enabling these two vital functions to be supported and taken over by drugs and machines. Traditional definition of death will be inappropriate in such situations, and a different method to ascertain death is therefore required. Permanent cessation of the heart and respiration results in inevitable irreversible loss of brain function which cannot be taken over by machines. It is the ultimate organ that determines life and death because the brain determines whether the organism can still function as a coordinated whole or otherwise.
The criteria for diagnosis of brain death has evolved for more than 30 years. Brain death is a clinical diagnosis. The presence of irreversible brain damage must be established. Metabolic factors must be ruled out as the cause of the patient’s condition. The patient must be apnoiec (i.e. makes no respiratory effort). The patient is totally unreceptive and unresponsive with the absence of brain stem reflexes while being properly ventilated.
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