Systemic Inflammatory Response Syndrome as Predictor of Poor Outcome in Nontraumatic Subarachnoid Hemorrhage Patients

Objectives: Subarachnoid hemorrhage is a life-threatening disease associated with high mortality and morbidity. A substantial number of patients develop systemic inflammatory response syndrome. We aimed to identify risk factors for systemic inflammatory response syndrome development and to evaluate the role of systemic inflammatory response syndrome on patients' outcome. Design: Retrospective observational cohort study of prospectively collected data. Setting: Neurocritical care unit at a tertiary academic medical center. Patients: Two-hundred and ninety-seven consecutive nontraumatic subarachnoid hemorrhage patients admitted to the neurologic ICU between 2010 and 2017. Interventions: Systemic inflammatory response syndrome was diagnosed based on greater than or equal to two criteria (hypo-/hyperthermia, tachypnea, leukopenia/leukocytosis, tachycardia) and defined as early ( 3 d) and delayed (days 6-10) systemic inflammatory response syndrome burden (systemic inflammatory response syndrome positive days within the first 10 d). Using multivariate analysis, risk factors for the development of early and delayed systemic inflammatory response syndrome and the relationship of systemic inflammatory response syndrome with poor 3-month functional outcome (modified Rankin Scale score 3) were analyzed. Measurements and Main Results: Seventy-eight percent of subarachnoid hemorrhage patients had early systemic inflammatory response syndrome, and 69% developed delayed systemic inflammatory response syndrome. Median systemic inflammatory response syndrome burden was 60% (interquartile range, 10-90%). Risk factors for early systemic inflammatory response syndrome were higher admission Hunt and Hess grade (odds ratio, 1.75; 95% CI, 1.09-2.83; p = 0.02), aneurysm clipping (odds ratio, 4.84; 95% CI, 1.02-23.05; p = 0.048), and higher modified Fisher Scale score (odds ratio, 1.88; 95% CI, 1.25-2.89; p = 0.003). Hunt and Hess grade and pneumonia were independently associated with delayed systemic inflammatory response syndrome development. Systemic inflammatory response syndrome burden (area under the curve, 0.84; 95% CI, 0.79-0.88) had a higher predictive value for 3-month poor outcome compared with early systemic inflammatory response syndrome (area under the curve, 0.76; 95% CI, 0.70-0.81; p < 0.001). Conclusions: Systemic inflammatory response syndrome is common after subarachnoid hemorrhage and independently contributes to poor functional outcome. Systemic inflammatory response syndrome burden more accurately predicts poor outcome than early systemic inflammatory response syndrome.