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Respiratory

SpO₂/FiO₂ Ratio (S/F Ratio)

Non-invasive oxygenation index for pediatric ARDS (PALICC-2), using pulse oximetry instead of an arterial gas.

Scope: Non-invasive surrogate only; confirm with an arterial gas (OI) when intubated. Unreliable above SpO₂ 97%.

Inputs

FieldUnitNotes
SpO₂ % Only valid at SpO₂ ≤97%
FiO₂ % 21–100

FAQ

What is the SpO₂/FiO₂ Ratio (S/F Ratio)?

Non-invasive oxygenation index for pediatric ARDS (PALICC-2), using pulse oximetry instead of an arterial gas.

What inputs does the SpO₂/FiO₂ Ratio (S/F Ratio) need?

SpO₂ (%), FiO₂ (%).

Are there any limitations?

Non-invasive surrogate only; confirm with an arterial gas (OI) when intubated. Unreliable above SpO₂ 97%.

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