Abstract TP309: Subarachnoid Extension of Hemorrhage Is Associated with Poor Outcomes in Primary Intracerebral Hemorrhage

Abstract

Background: Extension of hemorrhage into the subarachnoid space is observed in primary intracerebral hemorrhage (ICH), yet the phenomenon has undergone limited study and is of unknown significance. The objective of this study is to evaluate the incidence, characteristics and clinical consequences of subarachnoid hemorrhage extension (SAHE) in ICH. Methods: Patients with primary ICH were enrolled into a prospective registry between December 2006 and July 2012. Patients were managed, and serial neuroimaging obtained, per a structured protocol. SAHE was identified on imaging, along with ICH volumes, by expert reviewers blinded to outcomes. Ordinal regression models were developed to test whether the occurrence of SAHE was a predictor of functional outcomes independent of ICH Score, with confirmation of model validity by appropriate tests. Results: 234 patients were studied, and 93 (39.7%) had SAHE. SAHE was associated with lobar hemorrhage location (65% of SAHE versus 19% of non-SAHE cases, p<0.001), and larger hematoma volumes (median 23.8 versus 6.65, p<0.001). SAHE was a predictor of higher modified Rankin Scale scores (mRS) at discharge (odds ratio 2.22 per mRS point [95% CI 1.29-3.81]) and 28 days (1.80 [1.04-3.11]) after adjustment for ICH Score. Conclusions: SAHE is associated with poor outcomes independent of traditional ICH severity measures. Further exploration of this phenomenon to understand the underlying mechanisms of harm is needed.