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A-a Gradient BODE Index GOLD Staging Lungs Age P/F Ratio PEFR Calculator Wells PE Criteria

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P/F Ratio

PaO2/FiO2 (P/F) Ratio: The cornerstone of ARDS (Berlin) classification. Quantifies the severity of gas exchange impairment.

PaO2 (mmHg)

FiO2 (%)

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Wells PE Criteria

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