Bicarbonate Deficit Calculator

Estimate Bicarbonate Replacement Need

In metabolic acidosis, clinicians sometimes estimate how much bicarbonate is needed to reach a target serum level before or during replacement therapy. This calculator uses body weight, the measured bicarbonate, and a desired target, often 24 mmol/L, to estimate deficit in millimoles. See also the Anion Gap Calculator for related acid-base assessment.

Bicarbonate Deficit Formula

$$\text{deficit (mmol)} = 0.5 \times \text{weight (kg)} \times (\text{desired} - \text{actual}) \text{ mmol/L}$$

How to Use the Result

A positive deficit suggests bicarbonate replacement may be considered, but actual administration is usually partial and titrated to response. If desired bicarbonate is less than or equal to the measured value, the calculated deficit is zero or negative and routine replacement may not be indicated. Always follow institutional protocols and repeat labs during treatment.