PM2047: Dysnatremia Associated with Higher Mortality and Length-of-stay in Hospitalized Children

Background: Sodium concentrations [Na+] outside of the physiologic range comprise the most common electrolyte disturbances in hospitalized patients. Recent adult studies have shown that fluctuations in [Na+] from baseline regardless of physiologic range are independent risk factors for mortality, though pediatric data are limited. We sought to determine the nature of the relationship between dysnatremia and risk for poor outcomes in hospitalized children.

Methods: 7,247 pediatric patients with >1 [Na+] draw within 24 hours of admission between January 2000 and May 2018 were included in descriptive analysis. Of these, 3,925 patients had ≥1 additional [Na+] measurement and were divided based on the difference between peak and nadir [Na+] measurements. Logistic regression analysis was performed to identify variables that served as significant predictors of clinical outcomes.

Results: 17.4% and < 1% of patients were hyponatremic and hypernatremic on admission, while 7.34% and 10.9% of patients acquired hyponatremia and hypernatremia in the hospital. 20.5% of patients required ICU admission and 1.9% (n=137) experienced mortality within 1-year. Adjusted analyses showed Δ[Na+] of 10-11 (OR = 4.0 (95% CI 1.6-10.3)), >12 (OR = 7.3 (95% CI 3.0-17.6)), and hypernatremia (OR = 4.2 (95% CI 2.3-7.8)) were associated with higher odds of 1-year mortality. Fluctuations in [Na+] of ≥6 were associated with increased hospital length of stay, as shown in Table 1.

Conclusion: Our findings demonstrate that Δ[Na+] are associated with adverse outcomes in hospitalized children. Hospital-induced hypernatremia was more common than hospital-induced hyponatremia, raising concerns regarding the risks of default use of 0.9% saline. 1-year mortality and increased hospital LOS are more associated with absolute and hospital-acquired hypernatremia than hyponatremia. Our data suggest that careful attention to hypernatremia and degree of Δ[Na+] are warranted.