What sodium base should be given to children who are unable to eat? Recent studies have suggested that the traditional teaching of 0.45% normal saline (NS), 0.33% NS or 0.2% NS may cause iatrogenic hyponatremia when compared to an isotonic solution (0.9% NS, Ringers lactate or Hartmann's solution).
A meta-analysis of 8 studies with 855 patients examined the rate of hyponatremia when using hypotonic versus isotonic solutions.
-Studies included were randomized controlled trials with children age 1 month to 17 years.
-Children needing any type of resuscitation were excluded.
-Hyponatremia was defined as a sodium < 136 mmol/L.
-There is a higher risk when using hypotonic fluids for developing hyponatremia (RR 2.24) and severe hyponatremia (RR 5.29).
-The decrease in sodium was greater when hypotonic solutions were used.
-No significant difference in the rate of hypernatremia (Na>150 mmol/L)
-The type of fluid given (not rate) correlated with the risk of hyponatremia.
-Conclusions could not be drawn on the clinical significance of the iatrogenic hyponatremia
Bottom line: Make a conscience decision about maintenance fluids. Be sure to monitor Na levels for patients that you place on maintenance fluids and who are in your ED for prolonged periods of time.
References
Wang et al. Isotonic Versus Hypotonic Maintenance IV Fluids in Hospitalized Children: A Meta-Analysis. Pediatrics 2014; 133;105.
