The use of the pulse oximetric saturation to fraction of inspired oxygen ratio in an automated acute respiratory distress syndrome screening toolâ˜

PurposeTo determine the relationship between the pulse oximetric saturation to fraction of inspired oxygen (SF) ratio and the arterial partial pressure of oxygen to the fraction of inspired oxygen (PF) ratio, and to assess the usefulness of the SF ratio in an automated acute respiratory distress syndrome (ARDS) screening tool.Material and methodsThis was a retrospective cohort study using the Multiparameter Intelligent Monitoring in Intensive Care II database. The relationship was derived and validated in all patients ventilated for at least 24 hours.ResultsThe total data set included 7544 paired measurements from 3767 intensive care unit admissions. The correlation between SF ratio and PF ratio in the whole data set was good (Spearman ρ = 0.72, P < .001). An automated ARDS diagnostic tool using the derived SF cutoff had excellent agreement with the same tool using the PF ratio of 300 (κ = 0.87).ConclusionThe SF ratio may be an adequate substitute for the PF ratio in an automated ARDS screening tool.