Effect of rehydration fluid with 75 mmol/L of sodium on serum sodium concentration and serum osmolality in young patients with diabetic ketoacidosis.

OBJECTIVE

To evaluate whether rehydration of young patients with diabetic ketoacidosis (DKA) by use of a solution that contained 75 mmol/L of sodium would be associated with a decline in serum sodium concentrations.

DESIGN

We retrospectively studied 18 episodes of moderate to severe DKA (mean plasma bicarbonate concentration of 7.8 +/- 0.9 mmol/L) in 17 patients younger than 18 years of age who had been examined at the Mayo Clinic between 1986 and 1990.

MATERIAL AND METHODS

All patients had received an initial fluid bolus (about 20 mL/kg) of 0.9% saline or Ringer's lactate (or both), followed by rehydration with solutions that contained 75 mmol/L of sodium at rates of approximately 3,000 mL/m2 per day. Mean corrected and uncorrected serum sodium concentrations and effective serum osmolality (before and after administration of the fluid bolus and at 6 and 12 hours into treatment) were compared by use of the paired Student t test.

RESULTS

After 12 hours of therapy, we found a significant increase in the mean uncorrected serum sodium level from 135.1 +/- 0.9 mmol/L to 138.1 +/- 0.7 mmol/L (P < 0.05), whereas the mean corrected serum sodium value declined slightly from 143.1 +/- 1.1 mmol/L to 140.4 +/- 0.7 mmol/L (statistically not significant). Serum osmolality based on uncorrected serum sodium concentrations decreased at a rate of 2.6 mmol/kg per hour during the first 6 hours of treatment and remained stable thereafter.

CONCLUSION

In 18 episodes of DKA in young patients, rehydration with fluids that contained 75 mmol/L of sodium at rates of approximately 3,000 mL/m2 per day after administration of a fluid bolus of 0.9% saline or Ringer's lactate (or both) was not associated with a decline in the uncorrected serum sodium concentration.