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Anaesthesia / Critical Care Respiratory Emergency Medicine Strong — JAMA 2012 (Berlin Definition)

P/F Ratio (Horowitz Index)

PaO₂/FiO₂ ratio. Quantifies oxygenation efficiency and is the cornerstone of the Berlin ARDS Definition. Normal >400. Enter PaO₂ from ABG and FiO₂ as a percentage.

Arterial partial pressure of oxygen from ABG

Fraction of inspired oxygen as a percentage. Room air = 21, pure O₂ = 100

References

Related

Curated clinical cross-links plus same-class fallbacks.

Decision support only — verify against MDCalc, NICE, or your local guideline before clinical use.