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Pulmonology · Critical Care

Alveolar Gas Equation (PAO2) calculator

Enter the published formula inputs below to calculate and interpret this score.

Clinical inputs

Result

Complete all required inputs to calculate the score.

Formula inputs

  • Alveolar Fio2 Fraction (fraction)Accepted range: 0.21 to 1
  • Alveolar Patm Mmhg (mmHg)Accepted range: 400 to 760
  • Alveolar Paco2 Mmhg (mmHg)Accepted range: 10 to 100
  • Alveolar Rq (ratio)Accepted range: 0.7 to 1

Primary source

Rossi A et al. Physiology of the alveolar gas equation. Eur Respir J. DOI: 10.1183/13993003.0123-2016. PMID: 27053832. Scope: PAO2 (mmHg) = FiO2 × (Patm − PH2O) − PaCO2/RQ with PH2O = 47 mmHg at body temperature. (2016)

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