What is Winters’ Formula?
Winters’ formula is used to calculate a patient’s predicted PaCO2 based on their arterial blood gas (ABG) results.
The formula uses the following equation:
Expected PaCO2 = (1.5 x HCO3-) + 8 ± 2
The patient’s bicarbonate value (HCO3-) is obtained by collecting and analyzing a sample of arterial blood. Then you can use Winters’ formula to determine the expected PaCO2 simply by inserting the HCO3- value into the equation.
