🫁 Oxygenation Index (OI)
Calculate the oxygenation index (OI) for ventilated patients, central to paediatric ARDS grading.
Oxygenation Index (OI)
FiO₂ (fraction)
Mean airway pressure (cmH₂O)
PaO₂ (mmHg)
When to use
Grade oxygenation severity incorporating ventilator support.
How it works
OI = (FiO₂% × mean airway pressure) / PaO₂. PALICC: 4–8 mild, 8–16 moderate, ≥ 16 severe.
Key points
- Accounts for mean airway pressure, unlike the P/F ratio.
- Higher OI = worse oxygenation.
- Oxygen saturation index (OSI) is a non-invasive analogue.
References
Decision support for licensed clinicians only; not a substitute for clinical judgement, diagnosis or local protocols.