Abstract
Intrapulmonary shunt, cardiac output, and O2 consumption as factors contributing to alveolar-arterial O2 tension difference (A-aDo2) were tested in 11 patients after open-heart surgery. A-aDo2 was well correlated with intrapulmonary shunt, as expected, but no correlation was found between cardiac index (CI) and intrapulmonary shunt. When total shunt (venous admixture) was above 11%, there was an inverse correlation between A-aDo2 and CI, and it was observed that CI falling below 2.5 L/min/sq m contributed significantly to the enlargement of A-aDo2. Low Pao2 (less than 65 torr, breathing air) was characterized by larger arterial-mixed venous O2 content difference than high Pao2 (is greater than 65 torr, on room air), indicating that A-aDo2 was influenced by cardiac output relative to metabolic demand. Intrapulmonary shunt played a main role in increasing A-aDo2 after open-heart surgery, and systemic factors, including changes in cardiac output and O2 consumption, also contributed to development of hypoxia.
Sign-in/Register to access full text options 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
