anatomy and physiology
Last reviewed 01/2018
The diagnosis of brainstem death is made when the ascending reticular activating system (ARAS) is irreversibly damaged such that awareness/consciousness may never be attained.
It must be clearly demonstrated that in the absence of features that may mask ones clinical signs, the ARAS is not functioning and will not regain function. This state may be inferred from the functional status of the cranial nerve brainstem nuclei which are in intimate anatomical asociation with the ARAS.
The presence of an anatomical lesion and to some degree its irreversibility, are determined by CT or MRI scan.