PHYScalc: PF Ratio

P/F Ratio (PaO₂/FiO₂) – CC-OrangeCard PaO₂/FiO₂ (P/F) Ratio Calculator PaO₂ mmHg = 10.7 kPa PaO₂ (alt) kPa = 80 mmHg FiO₂ % = 0.40 P/F (mmHg) mmHg P/F (kPa) kPa Severity Normal oxygenation Normal: > 300 mmHg (> 40 kPa) Mild ARDS: 200–300 mmHg (26.7–40 kPa) Moderate ARDS: 100–200 mmHg (13.3–26.7 kPa) Severe ARDS: <= […]

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Blood Gases

I’m going to focus on Arterial blood gases here. Venous gases are close enough in well people, but beware in critical illness there is divergence between arterial and venous samples, particulary in CO2, lactate and pH. Method FiO₂ Calculator 713 x 0.21 = 150 mm Hg Differential Diagnosis HAGMA (CATMUDPILES or LTKR) NAGMA (CAGE, ABCD, […]

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