Auditory evoked brainstem responses (ABR) in coma due to severe head trauma.

Auditory evoked brainstem responses (ABR) were recorded in 11 comatose patients suffering from severe head trauma. The recordings were performed while the patients were being cared for in the neurosurgical intensive care unit. The ABR results, together with the clinical laboratory data, were correlated to the outcome for the patients. In 6 patients who died of their brain injuries, complete autopsies together with transverse cutting of the brainstem were performed in order to chart the extent of the brainstem lesions. Our findings suggest that the ABR test is a reliable diagnostic tool for predicting the outcome of patients comatose as a result of head trauma. The interpretation of the ABR results in cases suspected of brain death is discussed in the light of an illustrative case report.