Auditory and somatosensory evoked potentials in coma following spontaneouscerebral hemorrhage: early prognosis and outcome

The aim of this study was to check the prognostic power of auditory brain-s tem responses (ABRs) and somatosensory evoked potentials (SEPs) in coma fol lowing spontaneous cerebral hemorrhage. Seventy patients comatose following subarachnoidal or hypertensive hemorrhage were submitted to ABR and SEP re cordings during the acute phase of clinical course. Twenty-one patients sur vived (30%), two remained vegetative (2.9%) and 47 died (68.1%). The Glasgo w Coma Score (GCS) was significantly related to the outcome (P < 0.001), bu t showed a low sensitivity, since about 50% of patients with GCS = 5-8 died or remained vegetative. ABRs and SEPs showed a much closer correlation wit h outcome (P < 0.001): their combined use allowed there to be a sensitivity of 96%, a specificity of 90% and a predictive power of 96%; the relative r isk of poor outcome in patients with at least one abnormal modality was equ al to 223 times the one for patients with normal evoked potentials. Moreove r, in surviving patients a significant relationship appeared to exist betwe en abnormalities of SEPs during the acute phase and the severity of disabil ity. Our results confirm the prognostic effectiveness of short latency evok ed potentials in cerebral hemorrhage: they are far superior to clinical dat a, being able to yield a marked decrease of falsely optimistic predictions. (C) 1998 Elsevier Science Ireland Ltd. All rights reserved.