Therapeutic hypothermia after cardiac arrest: performance characteristics and safety of surface cooling with or without endovascular cooling.

INTRODUCTION: Various methods are available to induce and maintain therapeutic hypothermia after cardiac arrest, but little data is available comparing device-mediated cooling to simple surface methods in this setting. METHODS: To assess the performance characteristics of simple surface cooling with or without an endovascular cooling catheter system, we retrospectively reviewed all cases of hypothermia for comatose survivors of cardiac arrest treated at a single academically affiliated urban hospital. Forty two comatose survivors of cardiac arrest were treated over a 3.5-year period. Hypothermia was induced and maintained by simple surface methods (ice packs, cooling blankets) with or without placement of an endovascular cooling catheter system with automated temperature feedback regulation. RESULTS: Overall, the rate of active cooling was not different between patients treated with endovascular catheter-assisted hypothermia and patients treated with surface cooling alone. However, use of a larger (14 F) catheter was associated with faster cooling rates. Maintenance of goal temperature (33 degrees C) was far better controlled with the use of a cooling catheter. Use of surface cooling alone was associated with significant temperature overshoot. Patients treated with surface cooling alone spent more time bradycardic. CONCLUSION: Use of an endovascular cooling catheter as part of a treatment protocol for hypothermia after cardiac arrest provides better control during maintenance of hypothermia, preventing temperature overshoot. Active cooling rates may be enhanced by the use of a larger cooling catheter.

Prognostic significance of angiographically confirmed large vessel intracranial occlusion in patients presenting with acute brain ischemia.

INTRODUCTION: Independent predictors of outcome for ischemic stroke include age and initial stroke severity. Intracranial large-vessel occlusion would be expected to predict poor outcome. Because large-vessel occlusion and stroke severity are likely correlated, it is unclear if largevessel occlusion independently predicts outcome or is simply a marker for stroke severity. METHODS: A consecutive series of patients with suspected stroke or transient ischemic attack were imaged acutely with computed tomography angiography (CTA). CTAs were reviewed for intracranial large-vessel occlusion as the cause of the stroke. Baseline National Institutes of Health Stroke Scale (NIHSS) score, discharge modified Rankin score, and patient demographics were abstracted from hospital records. Poor neurological outcome was defined as modified Rankin score exceeding 2. RESULTS: Seventy-two consecutive patients with acute ischemic stroke were imaged with CTA. The median (range) time from stroke symptom onset to CT imaging was 183 minutes (25 minutes to 4 days). Median NIHSS score was 6 (1-32) and intracranial large-vessel occlusion was found in 28 (38.9%) patients. Fifty-six percent of patients had a good neurological outcome. In multivariate logistic regression analysis, two variables predicted poor neurological outcome: baseline NIHSS score (OR 1.21, 95% CI [1.07-1.37]) and presence of intracranial large-vessel occlusion (OR 4.48, 95% CI [1.19-16.9]). The predictive value of large-vessel occlusion on outcome was similar to an 8-point increase in NIHSS score. CONCLUSION: In patients presenting with acute brain ischemia, intracranial large-vessel occlusion independently predicts poor neurological outcome at hospital discharge, as does the presence of a high NIHSS score. Performing routine intracranial vascular imaging on acute stroke patients may allow for more accurate determination of prognosis and may also guide therapy.

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

BACKGROUND: 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. OBJECTIVE: To determine effective thrombolytic treatment times for posterior circulation stroke and factors that might help predict clinical outcome. DESIGN: 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. MAIN OUTCOME MEASURES: 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. RESULTS: 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. CONCLUSIONS: 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.