노사 판정의 임상적 Procedure

The various aspects of brain death have been subjects of close study by several professional committees, which have for the most part confirmed the 1968 guidelines and clinical protocols for determining that the brain is dead. The central considerations in the diagnosis of brain death are 1) absence of cerebral functions(unreceptivity and unresponsivity); 2) absence of brain stem functions including spontaneous respiration; 3) irreversibility of the state. To these is usually added evidence of catastrophic brain diseases.

The absence of cerebral function is judged by the presence of deep coma and total lack of spontaneous movement and motor and vocal response to all visual, auditory, and cutaneous stimulation. The absence of brain stem function is judged by absence of spontaneous eye movements, midposition of the eye, and lack of response to oculocephalic and caloric (oculovestibular) testing; presence of dilated or midposition fixed pupils; paralysis of bulbar musculature(no facial movement or gag, cough, corneal, or sucking reflexes); absence of decerebrate responses to noxious stimuli; and absence of respiratory movements. As a final test of complete apnea, the patient can be disconnected from the respirator for a few minutes, allowing the PC02 to rise to 50 to 60 mmHg, as a stimulus to the medullary respiratory centers. The EEG provides confirmation of cerebral death, and most institutions still demand proof of electrocerebral silence, which be considered to be present if there is no electrical potential of more than 2 V during a 30-min recording. Other variable laboratory tests including cerebral angiography, isotope brain scan, transcranial Doppler, and evoked potential studies are occasionally performed as an ancillatory procedure when the results of the apnea test or the EEG are equivocal. The main difficulties that arise in relation to brain death are not the purely technical issues, but those involving the sensitive management of the family and other medical professionals. It is best not to embark on.