Background: Hypertonic sodium chloride (HTS) is used in intensive care unit (ICU) settings to manage cerebral edema, intracranial hypertension, and for the treatment of severe hyponatremia. It has been associated with an increased incidence of hyperchloremia; however, there is limited literature focusing on hyperchloremic risk in neurologically injured patients. Objective: The primary objective of this study was to determine risk factors associated with development of hyperchloremia in a neurocritical care (NCC) ICU population.
Methods: This was a retrospective case-control study performed in an adult NCC ICU and included patients receiving HTS. The primary outcome was to evaluate patient characteristics and treatments associated with hyperchloremia. Secondary outcomes included acute kidney injury and mortality.
Results: Overall, 133 patients were identified; patients who were hyperchloremic were considered cases (n = 100) and patients without hyperchloremia were considered controls (n = 33). Characteristics and treatments were evaluated with univariate analysis and a logistic regression model. In the multivariate model, APACHE II Score, initial serum osmolality, total 3% saline volume, and total 23.4% saline volume were significant predictors for hyperchloremia. In addition, patients with a serum chloride greater than 113.5 mEq/L were found to have a higher risk of acute kidney injury (AKI) (adjusted OR 3.15; 95% CI 1.10-9.04).
Conclusions: This study demonstrated APACHE II Score, initial serum osmolality, and total 3% and 23.4% saline volumes were associated with developing hyperchloremia in the NCC ICU. In addition, hyperchloremia is associated with an increased risk of AKI.
Keywords: acute kidney injury; hyperchloremia; hypertonic saline; neurocritical care.