Winters_Metabolic_Acidosis_Compensation v.1

Winters' Formula for Metabolic Acidosis Compensation helps to calculate the expected respiratory compensation needed for a purely metabolic acidosis.

Syeeda S Farruque

models@cambiocds.com

© Cambio Healthcare Systems

Winters' Formula for Metabolic Acidosis Compensation helps to calculate the expected respiratory compensation needed for a purely metabolic acidosis.

With a patient with a suspected pure metabolic acidosis and a patient with a mixed acidosis to determine the level of compensation. The formula uses a bicarbonate value in mmol/L and provides a range that is +/- 2 either side of the calculated value. Expected PaCO2 in kPa = 1.5*HCO3 + 8 +/- 2 [This calculation applies in mmHg and so needs to be converted to kPa after calculation which can be done by multiplying the result by 0.133322] (1) There is a 1mEq/l drop in Hco3 to each 1mmHg drop in PaCo2 (2)

Do not use to diagnose but to calculate the respiratory compensation as provided by receiving an accurate bicarbonate value.

Ref. 1: Adrogué, H.J. (2006). Metabolic acidosis: pathophysiology, diagnosis and management. Journal of nephrology, 19 Suppl 9, S62-9. Ref. 2: Albert MS, Dell RB, Winters RW. Quantitative Displacement of Acid-Base Equilibrium in Metabolic Acidosis. Ann Intern Med. 1967;66:312-322. doi:10.7326/0003-4819-66-2-312.

OBSERVATION.lab_test-blood_gases.v1, OBSERVATION.winters_formula_for_metabolic_acidosis_compensation.v1