Journal of Applied Physiology AJP: Cell Physiology
HOME HELP FEEDBACK SUBSCRIPTIONS ARCHIVE SEARCH TABLE OF CONTENTS
QUICK SEARCH:   [advanced]


     

J Appl Physiol 19: 43-47, 1964;
8750-7587/64 $5.00
This Article
Right arrow Full Text (PDF)
Right arrow Submit a response
Right arrow Alert me when this article is cited
Right arrow Alert me when eLetters are posted
Right arrow Alert me if a correction is posted
Services
Right arrow Email this article to a friend
Right arrow Similar articles in this journal
Right arrow Similar articles in PubMed
Right arrow Alert me to new issues of the journal
Right arrow Download to citation manager
Citing Articles
Right arrow Citing Articles via HighWire
Right arrow Citing Articles via Google Scholar
Google Scholar
Right arrow Articles by Ayres, S. M.
Right arrow Articles by Grabovsky, E.
Right arrow Search for Related Content
PubMed
Right arrow PubMed Citation
Right arrow Articles by Ayres, S. M.
Right arrow Articles by Grabovsky, E.

Components of alveolar-arterial O2 difference in normal man

Stephen M. Ayres 1, Antoinette Criscitiello 1, and Evdokia Grabovsky 1

1 Departments of Medicine, Saint Vincent's Hospital, New York City, and Saint Michael's Hospital, Newark, New Jersey

The alveolar-arterial oxygen difference (A-aD) is believed due to true venous shunting, unequal distribution of alveolar ventilation (Va) to pulmonary capillary flow (Q), and diffusion limitations. Measurement of the A-aD was made at varying levels of alveolar oxygen tension in order to separate these three factors. The A-aD averaged 7.3, 15.2, and 37.1 mm Hg during the breathing of 14, 21, and 100% oxygen. The true venous shunt was 3.0 ± 1.9% of the systemic blood flow; unequal distribution of Va to Q resulted in an additional virtual shunt of 3.4 ± 2.6%. Breathing room air the diffusion component of the A-aD was negligible, true shunting accounted for 6.2 ± 4.0 mm Hg of the total A-aD. This created an A-aD of 9 and 0.6 mm for nitrogen and carbon dioxide, respectively. The method used could not distinguish the unequal Va/Q effect from the effect of unequal distribution of diffusion and perfusion.

true veno-arterial shunt; alveolar ventilation-pulmonary capillary flow ratio (Va/Q); pulmonary membrane diffusion (D); virtual shunt (unequal Va/Q effect); distributional and diffusion components of A-aD; perfusion of nonventilated alveoli; venous admixture diffusing capacity; venoarterial shunting; alveolar ventilation/perfusion ratios; arterial oxygen tension; platinum electrode

Submitted on May 22, 1963




This article has been cited by other articles:


Home page
 Am. J. Respir. Crit. Care Med.Home page
J. SANDOVAL, P. ALVARADO, M. L. MARTINEZ-GUERRA, A. GOMEZ, A. PALOMAR, S. MEZA, E. SANTOS, and M. ROSAS
Effect of Body Position Changes on Pulmonary Gas Exchange in Eisenmenger's Syndrome
Am. J. Respir. Crit. Care Med., April 1, 1999; 159(4): 1070 - 1073.
[Abstract] [Full Text] [PDF]


HOME HELP FEEDBACK SUBSCRIPTIONS ARCHIVE SEARCH TABLE OF CONTENTS
Visit Other APS Journals Online