در تاييد مرگ مغزي Auditory Brainstem Respenses- ABR استفاده از پاسخهاي شنيداري ساقه مغز

Use of Auditory Brain stem Responses (ABR) to confirm clinical brain death

Since years bygone, the brain had been the focus of considerable debate and controversy and the fears of declaring death had always been a dilemma. For a long time, this presumption prevailed that the only subtle sign of death was putrifaction and rigor mortis (2). In the presence of cardiac activity, the permanent loss of cerebral function, manifested clinically by the absence of purposeful responsiveness to external stimuli, cephalic reflexes, apnea, and an isoelectic electroencephalogram for at least 30 minutes in the absence of hypothermia and poisoning by central nervous system depressants indicate cerebral death. The ABR test can be an indicator ofpreserved brainstem function in difficult clinical situations and has been utilized in brain-dead patients (3, 4). Absence of ABR waves II through V despite a normal wave I indicates a significant lack of function in brain stem auditory tracts. This clinical trial was conducted on 62 male (30-75 years)who were in comatosed state. The ABR were clear and reproducible in comatosed patients in whom brain death was not documented, whereas these responses were not recordable in brain dead patients. The latter finding was confirmed using paraclinical monitors such as EEG, Cerebral angiography and CT Scan.