Bicarbonate Deficit Calculator
Calculates the bicarbonate deficit to guide sodium bicarbonate replacement in severe metabolic acidosis.
Score interpretation
Deficit < 50 mmol: Moderate metabolic acidosis.
→ Consider underlying cause before bicarbonate administration. Treat DKA with insulin, lactic acidosis with cause removal. Bicarbonate only if pH < 7.1 or life-threatening arrhythmia.
Deficit 50–150 mmol: Significant metabolic acidosis.
→ Replace half the calculated deficit over 2–4h (8.4% NaHCO₃ — 1 mmol/mL). Recheck ABG after replacement. Avoid rapid full correction — risk of alkalosis, hypokalaemia, intracellular acidosis.
Deficit > 150 mmol: Severe metabolic acidosis.
→ ICU/HDU. Replace one-third of deficit over 4–6h. Repeated ABG. Treat underlying cause aggressively. Consider RRT if renal failure or toxin-mediated acidosis.
Interpretation bands for the HCO₃ Deficit. Apply clinical judgement and local guidance.
References
- Adrogué HJ, Madias NE. Management of life-threatening acid-base disorders. N Engl J Med. 1998;338(1):26–34.
Related
Curated clinical cross-links plus same-class fallbacks.
- Hyperkalaemia Management · UK Kidney Association Guidelines 2020; NICE CKD Guidelines
- Rhabdomyolysis · Renal Association 2018; UpToDate 2024
- Hypocalcaemia (Adult) · Society for Endocrinology
- SIADH (Endocrine Perspective) · European Hyponatraemia Guidelines 2014
- Hepatorenal Syndrome · EASL 2018; ICA 2015
- Acute Kidney Injury (AKI) · KDIGO 2012 / NICE AKI 2019
Decision support only — verify against a current formulary, NICE, or your local guideline before clinical use.