[Prognostic evaluation of severe brain damage by auditory brainstem evoked potentials (BAEPs)]

Auditory brainstem evoked potentials (BAEPs) reflect activities of the brainstem auditory pathway and the influence of activities of structures surrounding the pathway. It is said that BAEPs are reliable in predicting the outcome of patients with severe brain damage. The author studied the relationship between initial BAEP findings, particularly interpeak latencies of waves I to V and waves III to V, and mortality as based on the cause of each disorder. BAEPs were sequentially recorded in 241 cases of various neurological diseases resulting in severe brain damage (GCS less than 8) during the first few days after onset. BAEPs were graded into four groups based on initial findings. Group A: all waves I to V were recorded (159 cases). Group B: waves IV & V absent (11 cases). Group C: either wave I or waves I & II only were recorded (28 cases), Group D: all waves absent. Prognosis in Group B & C was poor, only two patients surviving in a vegetative state. There were no survivors in Group D. The relationship in Group A between interpeak latencies (I-V ipl, III-V ipl) and prognosis is discussed. This group consisted of 41 cases subarachnoid hemorrhage, 29 cases hypertensive intracerebral hemorrhage, 5 cases severe cerebral infarction, 21 cases infratentorial cerebral vascular disease, 49 cases supratentorial severe head injury, and 14 cases infratentorial head injury. In deceased cases of subarachnoid hemorrhage and supratentorial head injury, there was significant prolongation of I-V ipl and III-V ipl over the mean latency of 20 normal subjects plus 2SD.(ABSTRACT TRUNCATED AT 250 WORDS)