Brainstem auditory evoked response and vestibulo-ocular reflex in severe head injury patients. A prospective study of 60 cases.

Brainstem auditory evoked response (BAER) performed in 60 serious head injury patients, over the last two year period at All India Institute of Medical Sciences, New Delhi have been analysed, to correlate the findings with ultimate outcome. All patients included in this study were unconscious, not following any command at the time of initial evaluation, mostly within 48 hours of injury. Repeat studies were performed in surviving patients. Computerized cranial tomography was performed to establish the nature of the intracranial pathology. The clinical status and cold caloric responses were recorded in all. The patients were followed up for 1 to 24 months. Three patients had extradural haematoma, 2 patients had subdural haematoma and 30 patients had intracerebral contusion/haematoma. Brain oedema was recorded in 14 cases. BAER was normal in 32 patients and 26 of them had good recovery (81%). Three patients with normal BAER died. Abnormal BAER was recorded in 21 patients and only 50% of them had good recovery and 25% of them died. In 7 patients BAER was absent and only 2 (29%) had a good recovery. Thus 48 out of 60 patients (66%) had a good recovery and 11 (18%) died. When compared to cold caloric response, 87% patients with normal caloric response had a good recovery and 5 out of 6 patients with absent caloric response died and remaining 1 left in a vegetative state. Thus the caloric response is at least as good a prognostic factor as BAER.