Hypernatremic Dehydration in Young Children: Is There a Solution?

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.

To describe the relationship between the type, route and rate of fluids administered and the rate of decline in serum sodium (Na+) concentration.

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.

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.

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.