PaO₂ / FiO₂ Ratio (Horowitz Index)
Key indicator of oxygenation failure severity. Berlin definition: mild ARDS < 300, moderate < 200, severe < 100.
Reference: ARDS Definition Task Force. JAMA 2012
Medical Disclaimer: This calculator is a clinical decision support tool for qualified healthcare professionals. It does not replace clinical judgement. Always interpret results in the full clinical context. Reference: ARDS Definition Task Force. JAMA 2012.
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