Bicarbonate Deficit Calculator

Your details

Ewald uses lean body weight and a fixed Vd of 0.5 L/kg. Standard uses actual weight and 0.4 L/kg. Kurtz uses a dynamic Vd that increases as HCO3 falls.
Used to calculate lean body weight (Devine formula). Required for the Ewald and Kurtz methods, both of which apply the volume of distribution to lean rather than actual body weight.
Actual (total) body weight.
kg
Used to derive lean body weight (Ewald and Kurtz methods).
cm
Patient's current arterial or venous bicarbonate level.
mEq/L
Desired bicarbonate after correction. Most protocols aim for 22-24 mEq/L, though initial targets of 15-18 mEq/L are used in severe acidosis to avoid overcorrection.
mEq/L
Bicarbonate deficitSevere deficit
281.9mEq

Total mEq of HCO3 needed to reach the target level

Initial dose (50% over 3-4 h)140.9mEq
Remainder (over 8-24 h)140.9mEq
Volume of distribution (Vd)0.5L/kg
Weight used in formula70.5kg
281.9 mEq
Mild<50Moderate50-150Severe150+

Total HCO3 deficit: 281.9 mEq - initial dose 140.9 mEq over 3-4 hours.

  • Using the Ewald formula (Vd 0.5 L/kg x lean body weight) with a weight of 70.5 kg, the total deficit is 281.9 mEq.
  • Standard protocols recommend giving 140.9 mEq (50% of the deficit) over the first 3-4 hours, then reassessing.
  • The measured HCO3 of 14 mEq/L is significantly low; normal is 22-26 mEq/L.
  • Overcorrection risks include hypokalemia, paradoxical CSF acidosis, and impaired oxygen delivery - target pH 7.20-7.25 initially.

Next stepSevere deficit - urgent medical evaluation is essential. Verify serum electrolytes (K+, Na+, Cl-) and arterial blood gas before initiating therapy.

 = Powered by OnlyCalculators