Faculty Bibliography

OBJECTIVE: We developed a modification of the Fisher computed tomographic rating scale and compared it with the original Fisher scale to determine which scale best predicts symptomatic vasospasm after subarachnoid hemorrhage. METHODS: We analyzed data from 1355 subarachnoid hemorrhage patients in the placebo arm of four randomized, double-blind, placebo-controlled studies of tirilazad. Modified Fisher computed tomographic grades were calculated on the basis of the presence of cisternal blood and intraventricular hemorrhage. Crude odds ratios (OR) reflecting the risk of developing symptomatic vasospasm were calculated for each scale level, and adjusted ORs expressing the incremental risk were calculated after controlling for known predictors of vasospasm. RESULTS: Of 1355 patients, 451 (33%) developed symptomatic vasospasm. For the modified Fisher scale, compared with Grade 0 to 1 patients, the crude OR for vasospasm was 1.6 (95% confidence interval [CI], 1.0-2.5) for Grade 2, 1.6 (95% CI, 1.1-2.2) for Grade 3, and 2.2 (95% CI, 1.6-3.1) for Grade 4. For the original Fisher scale, referenced to Grade 1, the OR for vasospasm was 1.3 (95% CI, 0.7-2.2) for Grade 2, 2.2 (95% CI, 1.4-3.5) for Grade 3, and 1.7 (95% CI, 1.0-3.0) for Grade 4. Early angiographic vasospasm, history of hypertension, neurological grade, and elevated admission mean arterial pressure were identified as risk factors for symptomatic vasospasm. After adjusting for these variables, the modified Fisher scale remained a significant predictor of vasospasm (adjusted OR, 1.28; 95% CI, 1.06-1.54), whereas the original Fisher scale was not. CONCLUSION: The modified Fisher scale, which accounts for thick cisternal and ventricular blood, predicts symptomatic vasospasm after subarachnoid hemorrhage more accurately than original Fisher scale.

The authors performed serial transcranial Doppler (TCD) and carbon dioxide reactivity (CO2R) testing in 20 aneurysmal subarachnoid hemorrhage patients to determine whether impaired cerebrovascular reactivity was associated with symptomatic vasospasm. Symptomatic vasospasm occurred in 9 of 14 patients with abnormal CO2R and in none of 6 patients with preserved reactivity (p = 0.011). Abnormal CO2R preceded the onset of vasospasm in 7 of 9 patients. Abnormal standard TCD testing was not associated with vasospasm.

OBJECTIVE: Medical complications occur frequently after subarachnoid hemorrhage (SAH). Their impact on outcome remains poorly defined. DESIGN: Inception cohort study. PATIENTS: Five-hundred eighty patients enrolled in the Columbia University SAH Outcomes Project between July 1996 and May 2002. SETTING: Neurologic intensive care unit. INTERVENTIONS: Patients were treated according to standard management protocols. MEASUREMENTS AND MAIN RESULTS: Poor outcome was defined as death or severe disability (modified Rankin score, 4-6) at 3 months. We calculated the frequency of medical complications according to prespecified criteria and evaluated their impact on outcome, using forward stepwise multiple logistic regression after adjusting for known predictors of poor outcome. Thirty-eight% had a poor outcome; mortality was 21%. The most frequent complications were temperature>38.3 degreesC (54%), followed by anemia treated with transfusion (36%), hyperglycemia>11.1 mmol/L (30%), treated hypertension (>160 mm Hg systolic; 27%), hypernatremia>150 mmol/L (22%), pneumonia (20%), hypotension (<90 mm Hg systolic) treated with vasopressors (18%), pulmonary edema (14%), and hyponatremia<130 mmol/L (14%). Fever (odds ratio [OR], 2.0; 95% confidence interval [CI], 1.1-3.4; p=.02), anemia (OR, 1.8; 95% CI, 1.1-2.9; p=.02), and hyperglycemia (OR, 1.8; 95% CI, 1.1-3.0; p=.02) significantly predicted poor outcome after adjustment for age, Hunt-Hess grade, aneurysm size, rebleeding, and cerebral infarction due to vasospasm. CONCLUSIONS: Fever, anemia, and hyperglycemia affect 30% to 54% of patients with SAH and are significantly associated with mortality and poor functional outcome. Critical care strategies directed at maintaining normothermia, normoglycemia, and prevention of anemia may improve outcome after SAH.