This Article Full Text (PDF) Alert me when this article is cited Alert me if a correction is posted Services Email this article to a friend Similar articles in this journal Similar articles in PubMed Alert me to new issues of the journal Download to citation manager Request Permissions Citing Articles Citing Articles via Google Scholar Google Scholar Articles by JAIN, K. K. Articles by LAMBERT, E. C. Search for Related Content PubMed PubMed Citation Articles by JAIN, K. K. Articles by LAMBERT, E. C.

(Circulation. 1970;41:55.)
© 1970 American Heart Association, Inc.

---

Comparison of Oxygen Saturation of Blood in Azygos Vein and Superior Vena Cava

KEWAL K. JAIN M.D.¹; HENRY R. WAGNER M.D.¹; EDWARD C. LAMBERT M.D¹

¹ From the Department of Pediatrics, Section of Cardiology, State University of New York at Buffalo, Buffalo, New York.

Blood samples from the superior vena cava (SVC) are usually considered an acceptable representation of mixed systemic venous return in identifying and quantifying left-to-right atrial shunts. However, if during sampling from the SVC unrecognized entrance of the catheter into the azygos vein takes place, diagnostic errors may result. Blood samples from the azygos vein were collected from 60 children with congenital heart disease and the oxygen saturations ranged from 20% to 92%. These saturations were compared to those of samples taken from the superior vena cava above the entrance of the azygos vein. No substantial difference (saturation within ±4%) was found in 24 patients, while 28 patients had a significantly higher saturation in the azygos vein (from +5% to +21%) and eight patients had a lower saturation (from –5% to –16%). A significant left-to-right shunt may be overlooked or erroneously thought to be present when sampling of blood takes place unknowingly from the azygos vein. Examples are presented.

Approaching from the groin it was possible to catheterize the azygos vein in two thirds of the cases when a deliberate attempt was made to do so.

Key Words: Cardiac catheterization • Shunts • Ventricular septal defect • Atrial septal defect

Submitted on July 22, 1969
Accepted on August 13, 1969