Target Serum Sodium Levels During Intensive Care Unit Management of Aneurysmal Subarachnoid Hemorrhage

ABSTRACT Introduction: Dysnatremia commonly occur in the intensive care unit (ICU) management of patients with aneurysmal subarachnoid hemorrhage (SAH). However, detailed management strategies have not been provided even by current guidelines. The purposes of this study were to examine the association of abnormal serum sodium levels with unfavorable neurologic outcomes and to identify the target range of serum sodium in patients with SAH. Methods: We retrospectively reviewed all patients who were consecutively hospitalized with a confirmed diagnosis of SAH between January 2009 and December 2015. Univariate/multivariate analyses were performed to identify the independent predictors of an unfavorable neurologic outcome (modified Rankin scale of 3–6 upon hospital discharge). Results: There were 131 patients included in this study. Unfavorable neurologic outcomes occurred in 45% of patients. On multiple regression analysis, age, Hunt and Kosnik grade, and serum sodium levels in the ICU at the maximum [odds ratio (OR), 1.18; 95% CI, 1.05–1.35; P < 0.01] and minimum (OR, 0.88; 95% CI, 0.77–0.99; P = 0.048) values were significantly associated with unfavorable neurologic outcomes. The receiver operating characteristic curve analysis showed that the cut-off serum sodium levels were 145 mmol/L for maximum value and 132 mmol/L for minimum value. Patients with hyponatremia and hypernatremia during the first 2 weeks in the ICU accounted for 88.2% of patients with an unfavorable neurologic outcome; whereas, those with normal sodium levels accounted for only 15.6%. Conclusions: In patients with SAH, both hyponatremia and hypernatremia during ICU management were significantly associated with unfavorable neurologic outcomes.