The EBMcalc module
a/A Ratio is available in
EBMcalc Complete Edition.
This calculator yields the following results:
Equation parameters include:
- PAtm
- PAH2O
- FIO2
- PaCO2
- Respiratory Quotient
- PaO2
References
- Hall RT. Indications for surfactant therapy--the aAPO2 coming of age. Pediatrics. 1999 Feb;103(2):E25. PubMed ID: 9925871
- West JB. Respiratory physiology: the essentials. 7th edition, Philadelphia, Lippincott William & Wilkins 2005. NLMN ID: 101205971

- Kanber GJ, King FW, Eshchar YR, et al. The alveolar-arterial oxygen gradient in young and elderly men during air and oxygen breathing. Am Rev Respir Dis. 1968 Mar;97(3):376-81. PubMed ID: 5638492
- Mellemgaard K. The alveolar-arterial oxygen difference: its size and components in normal man. Acta Physiol Scand. 1966 May;67(1):10-20. PubMed ID: 5963295
- Cole RB, Bishop JM. Variation in alveolar-arterial O2 tension difference at high levels of alveolar O2 tension. J Appl Physiol. 1967 Apr;22(4):685-93. PubMed ID: 6023181
- Lilienthal JL, Riley RL, et al. An experimental analysis in man of the oxygen pressure gradient from alveolar air to arterial blood during rest and exercise at sea level and at altitude. Am J Physiol. 1946 Sep;147:199-216. PubMed ID: 21000737
- Le Huu Thien B,Huynh Quang D. Equation des gaz alveolaires et difference alveolo-arterielle en oxygene. J Fran Viet Pneu. 2014; 05(14): 4-10.