Oxygenation Index Calculator
Calculate oxygenation index from FiO₂, mean airway pressure, and PaO₂.
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Oxygenation Index
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Reference index; no intervention is selected
Normalized FiO₂: —
About
Oxygenation Index (OI) combines inspired oxygen, mean airway pressure, and arterial oxygen tension. It is mainly used as a reference measure of oxygenation impairment in mechanically ventilated patients; age-group definitions and thresholds are not interchangeable.
Formula
Interpretation
What the result represents: Oxygenation impairment adjusted for both inspired oxygen and mean airway pressure.
Input units: FiO₂ must be explicitly selected as decimal (0.21–1.00) or percent (21–100%); mean airway pressure is cm H₂O and PaO₂ is mmHg.
Worked example: FiO₂ 0.60, mean airway pressure 12, and PaO₂ 60 gives OI = 12.0.
Applicable population: Mechanically ventilated patients with reasonably contemporaneous ventilator data and arterial blood gas measurement.
Interpretation limitations: Neonatal, pediatric, and adult frameworks use different contexts and thresholds. A single value does not determine intubation, ventilator adjustment, ECMO, or another intervention.
FAQ
Disclaimer
Educational and informational reference only. Not intended to replace professional medical advice, diagnosis, treatment, or independent verification.