Initial Glasgow Coma Scale score predicts outcome following thrombolysis for posterior circulation stroke

Randomized trials of thrombolytic stroke treatment have either excluded patients with posterior circulation ischemia or used inclusion criteria making enrollment of these patients less likely. Consequently, there is less published information on thrombolytic therapy for posterior circulation stroke.

To determine effective thrombolytic treatment times for posterior circulation stroke and factors that might help predict clinical outcome.

We describe our experience treating 21 consecutive patients with either intravenous or intra-arterial thrombolytic therapy for posterior circulation ischemic stroke between October 9, 1993, and February 19, 2001.

National Institutes of Health Stroke Scale, Glasgow Coma Scale, and modified Rankin Scale scores were evaluated at baseline, and the modified Rankin Scale was measured 3 months after stroke, with a good outcome being a modified Rankin Scale score of 2 or less.

Nine patients received intravenous therapy; 12 patients received intra-arterial therapy. The median National Institutes of Health Stroke Scale score at onset was 20 (range, 2-39), and the median Glasgow Coma Scale score was 9 (range, 3-15). Twelve patients were treated within 8 hours of symptom onset (range, 1 1/2 hours to 16 days). Nine patients (43%) had a modified Rankin Scale score of 2 or less at 3 months. The initial Glasgow Coma Scale score and treatment within 8 hours of symptom onset were each associated with good outcome, but the initial National Institutes of Health Stroke Scale score was not predictive.

Thrombolytic therapy for posterior circulation stroke may be beneficial even when initiated 8 hours after symptom onset. Level of consciousness, as measured by Glasgow Coma Scale score, seems to be a more important predictor of outcome than the initial National Institutes of Health Stroke Scale score.