The Cardiovascular
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Bicarbonate deficit

Estimates the bicarbonate needed to reach a target level.

Bicarbonate deficit
Body weight
Measured HCO3
mmol/L
Desired HCO3
mmol/L
Complete the fields above to see the result.

When to use

  • Estimating bicarbonate replacement in severe metabolic acidosis.

Formula

HCO3 deficit (mmol) = 0.5 × weight (kg) × (desired − measured HCO3). The distribution space (~0.5) rises toward 0.7–0.8 in severe acidaemia.

Pearls and pitfalls

  • Aim for partial correction (e.g. HCO3 ~15 or pH >7.2) rather than full normalisation.

References

  1. Adrogué HJ, Madias NE. N Engl J Med. 1998;338(1):26-34.