Background: Hypernatremic dehydration is a common and potentially life-threatening condition in children. There is currently no consensus as to the optimal strategy for fluid management.
Objectives: To describe the relationship between the type, route and rate of fluids administered and the rate of decline in serum sodium (Na+) concentration.
Methods: We reviewed the medical records of all children under the age of 2 years who were hospitalized with hypernatremic dehydration (serum Na+ ≥ 155 mEq/L) in Shaare Zedek Medical Center during the period 2001-2010. Collected data of 62 subjects included initial and subsequent serum Na+ levels, and rate and Na+ concentration of all intravenous and oral fluids administered until the serum Na+ reached ≤ 150 mEq/L.
Results: Median initial serum Na+ was 159.5 mEq/L (IQR 157-163, maximal value 170). The median rate of decline in serum Na+ until serum Na+ reached 150 mEq/L was 0.65 mEq/L/hr (IQR 0.45-0.95). Forty-two children received hypotonic oral fluids which accounted for approximately one-quarter of all fluids they received. There was no significant difference in the rate of decline in serum Na+ between those who consumed oral fluids and those who did not. Neither was there a correlation between the rate of IV fluids, receipt of oral fluids or the degree of dehydration, with the rate of decline in serum Na+. No child experienced an apparent short-term adverse outcome.
Conclusions: A cumulative rate of 5.9 mI/kg/hr of IV fluid administration may reduce the serum Na+ by an acceptable rate (0.65 mEq/L/hr). Fluid therapy comprising up to 25% hypotonic oral fluids and 75% IV fluids high in Na+ concentration was not associated with any short-term adverse outcome in our patient population.