Base excess (Van Slyke, Hgb-corrected)
Standard base excess (Siggaard-Andersen Van Slyke equation, NCCLS constants): the hemoglobin-corrected metabolic component of a blood gas.
Open the calculator → Runs in your browser. Data leaves only if you deliberately send a problem report from the interactive tool.
Example
- Arterial pH
- 7.2
- Bicarbonate
- 15 mEq/L
- Hemoglobin
- 15 g/dL
Result: Base excess -13 mEq/L: a base deficit, consistent with a metabolic acidosis.
The tool opens with these values already filled in. Replace them with your own.
What the result means
- Sign
- negative = base deficit (metabolic acidosis); positive = base excess (metabolic alkalosis); the sign flips at zero.
What you enter
- Arterial pH
- Bicarbonate
- Hemoglobin
How this is calculated
- Formula
- BE = (1 - 0.0143 x Hb) x (HCO3 - 24.8 + (9.5 + 1.63 x Hb) x (pH - 7.4)), hemoglobin in g/dL.
Siggaard-Andersen O. The Van Slyke equation. Scand J Clin Lab Invest Suppl. 1977;146:15-20. Read the source ↗
A reference and educational tool. Not medical, legal, or financial advice, and not a substitute for clinician judgment.