PROGNOSTIC VALUE OF SOMATOSENSORY-EVOKED RESPONSES IN COMATOSE PATIENTS WITH CEREBROVASCULAR ACCIDENTS - A PROSPECTIVE-STUDY

Short latency somatosensory evoked potentials (SSEPs) were recorded in 16 comatose patients 3.19 +/- 1.67 (mean +/- SD) days after the onset of a cerebrovascular accident. The SSEP, Glasgow Coma Scale (GCS) and Glasgow Outcome Score (GOS) results were compared. The SSEP, in all p atients with low SSEP grades, indicated an unfavourable outcome: 43.8% dead, 8.3% vegetative state and 25% severely disabled. Patients with good SSEP grades had a favourable outcome, 23% with moderate to good r ecovery. The SSEP findings correlated well with GCS scores at either e nd of the extremes of scale (GCS score of 3-14). Patients with high GC S score of 14 had high grades of both SSEP and P14. In contrast, those with low GCS score of 3 had low SSEP and P14 grades. There was a sign ificant correlation between SSEP grades and GCS scores (rs = 0.60; P < 0.050). We found a very high correlation between SSEP grades and GOS (rs = 0.91; P < 0.01). All patients with an unfavourable score (n = 11 ) had poor SSEP grades (1-3). In contrast, GCS scores had insignifican t correlation with Glasgow functional outcome (rs = 0.11; P < 0.1). Th e P14 (lemniscus medialis potential) had a significant moderate correl ation with total outcome (rs = 0.60; P < 0.05). P14 was absent in six patients whose EEG was isoelectric and fitted with the clinical criter ia of brainstem death. We conclude that the SSEP grading system in com atose patients has significant quantitative and prognostic value in th ose with strokes. P14 is important in identifying brainstem death. App lying these criteria of electrophysiological studies, the outcome for comatose patients could be classified to strengthen clinical evaluatio n. (C) 1998 Chapman & Hall Ltd.