Standards message here

medical collegeeducationresearchpatient caredepartments
Cornell Pediatrics

Dehydration Correction Calculator

Calculate the intravenous fluids required to correct isonatremic, hyponatremic, or hypernatremic dehydration.

Baseline Weight kg
Dehydrated Weight kg or % Dehydration 
Serum Na+ mEq/L
Replacement Interval hrs


Correct shock and treat hyponatremic seizures before initiating correction for dehydration. Consider ongoing losses and replace as appropriate. Exercise caution with large and non-pediatric patients.

Maintenance fluids are calculated based on the Holliday-Segar method. Maintenance sodium and potassium are calculated based on body weight per day: 3 mEq/kg/day, and 2 mEq/kg/day, respectively.

Deficit fluids are based on degree of dehydration. In hypernatremic dehydration, a fraction of the deficit fluids is a free water deficit (4 mL/excess Na+ in mEq/kg). Deficit sodium and potassium are calculated on the remaining fluid deficit: 0.6 * 145 mEq/L, and 0.4 * 150 mEq/L, respectively.

Correction of isotonic and hyponatremic dehydration replaces the first half of the deficit during the first third of the replacement interval. Correction of hypernatremic dehydration calls for correction of the first half of the free-water deficit during the first 24 hours.

The last line(s) of the fluid schedule is the "bottom line." Pick an appropriate, available, intravenous fluid that matches the specified concentrations and administer at the specified rate for the specified intervals. Consider using buffers such as acetate or phosphate as appropriate.

Calculations based on the Harriet Lane Handbook.


Created: June 3, 2009
Revised: June 3, 2009

Weill Medical College of Cornell University
Cornell University (Ithaca) | Privacy Notice | Disclaimer