Derivation and validation of Spo2/Fio2 ratio to impute for Pao2/Fio2 ratio in the respiratory component of the Sequential Organ Failure Assessment score*

Objective:The Sequential Organ Failure Assessment (SOFA) score is validated to measure severity of organ dysfunction in critically ill patients. However, in some practice settings, daily arterial blood gas data required to calculate the respiratory component of the SOFA score are often unavailable.