Predictors of shunt insertion in aneurysmal subarachnoid hemorrhage

Abstract Objects Hydrocephalus is a common complication of aneurysmal subarachnoid hemorrhage (aSAH) requiring permanent cerebrospinal fluid (CSF) diversion in up to two thirds of patients. Factors that predict permanent CSF diversion are not well established. Methods An exploratory analysis of 149 patients enrolled in the Cerebral Aneurysm Renin Angiotensin System (CARAS) study was performed in an effort to identify factors predictive of permanent CSF diversion following aSAH; only the 135 patients surviving the initial hospitalization were included in the present study. The CARAS was a prospective, multi-center study investigating the impact of genetic polymorphisms in aSAH and enrolled patients from September 2012 to January 2015. Results One hundred forty-nine aSAH patients were enrolled in CARAS with 135 (90.6%) patients surviving the initial hospitalization. Sixty-four of these patients (47.4%) ultimately required permanent CSF diversion. Multivariable analysis identified the following as independent risk factors: sympathomimetic illicit drug use, external ventricular drain (EVD) insertion, and hyponatremia. A scoring system based on EVD insertion (2 points), Hunt and Hess grade (1 point if grade ≥ 4) and modified Fisher CT grade (1 point if grade 4) produced an AUC of 0.8 (p < 0.001). Conclusion Sympathomimetic illicit drug use, EVD insertion, and hyponatremia are the strongest predictors of shunt insertion in aSAH patients. Moreover, a scoring system based on EVD insertion, Hunt and Hess grade, and modified Fisher CT grade can reliably predict the need for shunt placement in aSAH patients.