Evoked potentials in severe head injuries: a prospective study of 40 cases

Evoked potential (EP) studies were performed in 40 severe head injury patients with Glasgow Coma Scale 8 or below. CT scans were performed in all to evaluate the intracranial pathology. EP studies were performed within 48 hours of admission and outcome was correlated to the initial EP findings. Normal brainstem auditory evoked potentials (BAEP) and sensory evoked potentials (SEP) were recorded in 23 and 17 cases with a good recovery in 86.9% and 82.3% respectively. Absent BAEP and SEP were recorded in 6 and 10 cases with a good recovery in 33% and 50% respectively. When both were normal good outcome was recorded in 92.8% cases. All the patients in whom both BAEP and SEP were absent had a poor outcome. In this study BAEP had a better predictive value than SEP.