Fluid Intake But Not Fluid Balance Is Associated With Poor Outcome in Nontraumatic Subarachnoid Hemorrhage Patients

Abstract

Optimal fluid management is important in patients with acute brain injury, including subarachnoid hemorrhage. We aimed to examine the relationship between daily fluid intake and fluid balance with hospital complications and functional outcome. Retrospective observational cohort study. Neurocritical care unit at a tertiary academic medical center. Two-hundred thirty-seven consecutive nontraumatic subarachnoid hemorrhage patients admitted to the neurologic ICU between 2010 and 2016. Total daily amount of fluids and fluid balance were calculated over 15 days. Using multivariate generalized estimating equation models the association of daily fluid intake and fluid balance with disease severity, hospital complications and poor functional outcome (3-mo modified Rankin Score ≥ 3) was investigated. Additionally, we described the composition of fluids given. Patients presented with a median admission Hunt and Hess grade of 3 (interquartile range, 1-5) and were 57 years old (interquartile range, 47-67 yr old). A higher daily fluid intake was associated with higher admission Hunt and Hess grade (odds ratio, 1.61; 95% CI, 1.47-1.76; p < 0.001), increased pulmonary fluid accumulation (adjusted odds ratio, 1.11; 95% CI, 1.01-1.21; p = 0.033), prolonged mechanical ventilation (Wald statistic = 20.08; degrees of freedom = 1; p < 0.001), higher daily Subarachnoid hemorrhage Early Brain Edema Score (adjusted odds ratio, 1.11; 95% CI, 1.01-1.22; p = 0.034), occurrence of anemia (adjusted odds ratio, 1.36; 95% CI, 1.20-1.54; p < 0.001), delayed cerebral ischemia (adjusted odds ratio, 1.31; 95% CI, 1.14-1.51; p < 0.001), and poor functional outcome (adjusted odds ratio, 1.25; 95% CI, 1.10-1.41; p < 0.001). Daily fluid balance was associated with higher admission Hunt and Hess grade (odds ratio, 1.09; 95% CI, 1.05-1.13; p < 0.001) and anemia (adjusted odds ratio, 1.17; 95% CI, 1.03-1.33; p = 0.019). The main contributors to fluids were nutritional compounds (31%), IV drugs (30%), and volume substitution (17%). Our study demonstrates a significant association of fluid intake but not fluid balance with hospital complications and poor functional outcome in subarachnoid hemorrhage patients. A larger prospective study is needed to confirm our results.