Baseline National Institutes of Health stroke scale-adjusted time window for intravenous tissue-type plasminogen activator in acute ischemic stroke.

BACKGROUND AND PURPOSE: The effect of tissue-type plasminogen activator on functional outcome decreases progressively over time. However, given the differential pattern of arterial occlusion, stroke severity, and speed of ischemic lesion growth among candidates for reperfusion, the time window should be adjusted accordingly. We aimed to identify the impact of time-to-treatment according to stroke severity on functional outcome in patients with acute ischemic stroke. METHODS: We included 581 consecutive patients treated with alteplase according to the European Summary of Product Characteristics criteria. Patients were categorized according to National Institutes of Health Stroke Scale (NIHSS) severity in mild NIHSS (≤8), moderate NIHSS (9-15), and severe stroke NIHSS (≥16). We sequentially analyzed time-to-treatment to achieve favorable outcome (modified Rankin Scale ≤2 at 3 months). RESULTS: Overall, 19.8% had mild, 30.3% had moderate, and 49.9% had severe stroke. Favorable outcome occurred in 79.1%, 60.8%, and 26.2%, respectively. In patients with mild stroke, younger age (odds ratio [OR], 0.88; 95% confidence intervals [CI], 0.8-0.95), no previous history of stroke (OR, 0.16; 95% CI [0.039-0.65]), and no proximal occlusion (OR, 0.183; 95% CI [0.038-0.89]) independently predicted favorable outcome. In patients with moderate stroke, age (OR, 0.95; 95% CI [0.92-0.98]), no proximal occlusion (OR, 0.362; 95% CI [0.17-0.75]), and time-to-treatment before 120 minutes (OR, 2.70; 95% CI [1.14-6.38]) emerged as independent predictors of favorable outcome. In patients with severe stroke, younger age (OR, 0.96; 95% CI [0.94-0.99]), lower previous modified Rankin Scale (OR, 0.42; 95% CI [0.21-0.82]), and absence of proximal occlusion (OR, 0.48; 95% CI [0.25-0.94]) appeared as independent predictors. CONCLUSIONS: The impact of time-to-treatment on favorable outcome varies widely depending on baseline stroke severity. The window for favorable outcome was ≤120 min for moderate strokes. However, time-to-treatment seemed unrelated to functional outcome in mild and severe stroke.

Monitoring of cortical activity postreperfusion. A powerful tool for predicting clinical response immediately after recanalization.

BACKGROUND: In acute ischemic stroke, although early recanalization predicts rapid neurological recovery, in some cases early reperfusion does not immediately correlate to clinical improvement as "stunned brain" patients. The cortical activity monitoring in stroke patients is usually performed to evaluate epileptic activity through electroencephalogram. Bispectral index (BIS) monitor the cortical activity by fronto-temporal electrodes and is currently used for monitoring level of conscious on sedo-analgesia patients. Some studies have shown certain sensibility to detect cerebrovascular events during carotid revascularization. We aimed to evaluate the impact of BIS monitoring before and shortly after reperfusion on early and delayed clinical improvement on stroke patients. METHODS: Consecutive patients with acute anterior circulation ischemic stroke who received reperfusion therapies were monitored with bicortical BIS during the first 6 hours of admission. We registered initial and final BIS value on the affected and contralateral side and determined asymmetry and changes in relation to recanalization and other clinical variables as sedation and perprocedure complications. We defined major clinical improvement decrease ≥ 8 points at discharge or 5 day at admission. Infarct volume was measure on 24-hour CT scan. Modified Rankin score at 3 months was evaluated. RESULTS: A total of 53 patients were monitored with BIS. Median age was 73 years, median baseline National Institutes of Health Stroke Scale (NIHSS) 16. We observed an inverse correlation between final BIS score and NIHSS at discharge (P < .001; r = -.538) and infarct volume at 24 hours (P = .031; r = -.430). A receiver-operator characteristic curve identified a final BIS score of >81 as the value that better predicted further clinical improvement. After adjusting for recanalization, posttreatment NIHSS and age, final BIS emerged as the only independent predictor of clinical improvement(OR 1.21; CI 95%:1.01-1.28; P = .024). Among patients without improvement at 24 hours, after adjusting for recanalization, posttreatment NIHSS and age, final BIS value >81 emerged as the only independent predictor of clinical improvement(OR 11.6; CI 95%:1.112-122.3; P = .04). CONCLUSION: BIS value is associated with clinical and radiological variables in acute stroke patients. The final BIS value is a powerful independent predictor of further clinical improvement. Larger studies are needed to assess the value of post reperfusion cortical activity measured by BIS.