The Sofa score uses the P/F ratio to classify the severity of the respiratory compromise of a patient. However, scores 3, 4 require that a patient has respiratory support, but this is not clearly defined.

So if a patient is just on oxygen supplementation, or possibly CPAP, how would you score someone with a P/F ratio of < 200, >100? Similarly, if on mechanical ventilation, but a p/f ratio > 200, how would you score this?

Thanks

Stephen