Acute systemic inflammatory response syndrome in subarachnoid hemorrhage

Background and Purpose - Systemic inflammatory response syndrome (SIRS) without infection is a well-known phenomenon that accompanies various acute cerebral insults. We sought to determine whether the initial SIRS score was associated with outcome in subarachnoid hemorrhage (SAH). Methods - In 103 consecutive patients with SAH, the occurrence of SIRS was assessed according to the presence of ≥2 of the following: temperature of <36°C or >38°C, heart rate of >90 bpm, respiratory rate of >20 breaths/min, and white blood cell count of <4000/mm³ or > 12 000/mm³. SIRS criteria and other prognostic parameters were evaluated as predictors of dichotomous Glasgow Outcome Scale score. Results - SIRS was highly related to poor clinical grade (Hunt and Hess clinical grading scale), a large amount of SAH on CT (Fisher CT group), and high plasma glucose concentration on admission. By univariate analysis, the occurrence of SIRS was associated with higher mortality and morbidity rates than was the nonoccurrence (P<0.001). Among individual SIRS criteria, heart rate (P=0.003), respiration rate (P=0.003), and white blood cell count (P=0.03) were significant outcome predictors. By multivariate logistic regression analysis, the presence of SIRS independently predicted outcome. SIRS carried an increased risk of subsequent intracranial complications such as vasospasm and normal pressure hydrocephalus, as well as systemic complications. Conclusions - In SAH patients, SIRS on admission reflected the extent of tissue damage at onset and predicted further tissue disruption, producing clinical worsening and, ultimately, a poor outcome.