Tool -Measured PaCO₂ — mm Hg (optional)

PACO2 

1⛑️2 Not-Out. --Tool

Winter's Formula — PaCO₂ Estimator

Estimate the expected PaCO₂ (mm Hg) for metabolic acidosis and check if respiratory compensation is adequate.

Bicarbonate (HCO₃⁻) — mmol/L Measured PaCO₂ — mm Hg (optional)

Expected PaCO₂

— mm Hg

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Enter values and tap Calculate.

Clinical Notes:
Winter’s Formula: Expected PaCO₂ = 1.5 × [HCO₃⁻] + 8 ± 2 mm Hg.
• If measured PaCO₂ lies within the range → normal respiratory compensation.
• Higher PaCO₂ → concurrent respiratory acidosis or inadequate compensation.
• Lower PaCO₂ → concurrent respiratory alkalosis or excessive compensation.
• Always verify results with arterial blood gas (ABG) analysis.
• Common causes: diabetic ketoacidosis, lactic acidosis, renal failure, toxins.
This calculator is for educational and clinical support purposes only.