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. 2021 Apr 27;9(8):933–936. doi: 10.1016/S2213-2600(21)00105-3

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Proposed expansion of the Berlin definition of ARDS

ARDS=acute respiratory distress syndrome. HFNO=high-flow nasal oxygen. PaO₂/FiO₂=ratio of partial pressure of arterial oxygen to fraction of inspired oxygen.