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Respiratory

Oxygen Saturation Index (OSI)

Non-invasive oxygenation severity index (uses SpO₂ instead of PaO₂) for grading pediatric ARDS (PALICC).

Scope: Valid only with SpO₂ ≤97% (above that the SpO₂–PaO₂ relationship is flat). FiO₂ entered as a percentage.

Inputs

FieldUnitNotes
FiO₂ % 21–100
Mean airway pressure cmH₂O 1–50
SpO₂ % 50–100

FAQ

What is the Oxygen Saturation Index (OSI)?

Non-invasive oxygenation severity index (uses SpO₂ instead of PaO₂) for grading pediatric ARDS (PALICC).

What inputs does the Oxygen Saturation Index (OSI) need?

FiO₂ (%), Mean airway pressure (cmH₂O), SpO₂ (%).

Are there any limitations?

Valid only with SpO₂ ≤97% (above that the SpO₂–PaO₂ relationship is flat). FiO₂ entered as a percentage.

Related Respiratory calculators

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Validated acute asthma severity score from five signs (0–12).

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