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respiratory critical-care

SpO₂/FiO₂ (S/F) Ratio

Non-invasive surrogate for the PaO₂/FiO₂ ratio using pulse oximetry. Avoids arterial blood gas requirement. S/F ratio <315 correlates with ARDS (P/F <300).

References

Related

Curated clinical cross-links plus same-class fallbacks.

Decision support only — verify against MDCalc, NICE, or your local guideline before clinical use.