Abstract TP150: Association Of Asymptomatic Cerebral Vasospasm With Outcomes In Aneurysmal Subarachnoid Hemorrhage

Abstract

Cerebral vasospasm (cVSP) is a common complication in patients with aneurysmal subarachnoid hemorrhage (aSAH) and is associated with worse outcomes. However, clinical significance of asymptomatic cVSP remains poorly understood. We sought to determine the association between asymptomatic cVSP and hospital length of stay (LOS), duration of external ventricular drain (EVD), and functional outcome. We performed a retrospective cohort study of consecutive aSAH patients who were admitted to an academic referral center from 2016 to 2021. We included patients with confirmed aneurysmal etiology who received transcranial Doppler (TCD) with documented daily measurements. Multiple linear regression analysis was performed to test the association of asymptomatic cVSP (defined as elevated TCD velocities with no clinical correlation) and both hospital LOS and duration of EVD. Binary logistic regression analysis was used to test the association of asymptomatic cVSP and worse functional outcome (3-month modified Rankin scale 4-6). We included 223 patients (mean age 55.8 years [SD 13.4], 60% female, 70% white) with aSAH who survived hospitalization and had documented daily TCDs. Asymptomatic cVSP was seen in 32% of patients and delayed cerebral ischemia (DCI) was seen in 27% of patients. Only symptomatic cVSP was associated with prolonged hospital LOS (3.25 more days; p=0.034) independent of age, comorbidities, Hunt and Hess grades, modified Fisher scales, DCI, and other hospital complications. However, asymptomatic cVSP was associated with longer duration of EVD (3.78 more days; p=0.025) independent of common predictors including hydrocephalus and amount of cerebrospinal fluid daily output. Severity of vasospasm (ordinal variable: mild, moderate, or severe) was associated with longer duration of EVD (1.47 more days; p=0.016). Asymptomatic cVSP was not independently associated with worse functional outcome. In conclusion, isolated asymptomatic cVSP may not be associated with worse outcome but can contribute to interventions such as EVD prolongation. Clinical significance of asymptomatic cVSP and its management should be studied in multi-institutional prospective cohorts.