Open AccessChange in Pulmonary Venous Admixture With Varying Inspired Oxygen
Author(s) -
Michael E. Douglas,
John B. Downs,
Francis J. Dannemiller,
Michael R. Hodges,
Edwin S. Munson
Publication year - 1976
Publication title -
anesthesia and analgesia/anesthesia and analgesia
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.404
H-Index - 201
eISSN - 1526-7598
pISSN - 0003-2999
DOI - 10.1213/00000539-197609000-00016
Subject(s) - medicine , anesthesia , pulmonary artery , inhalation , venous blood , pulmonary function testing , shunting , blood gas analysis , arterial blood , mechanical ventilation , cardiology , respiratory system , oxygen , chemistry , organic chemistry
Pulmonary venous admixture (Qsp/Qt) was analyzed as a function of fractional concentration of inspired O2 (FIO2) in 30 patients who required postoperative mechanical ventilation. Pulmonary and radial artery blood-gas tensions and pH were measured and Qsp/Qt was calculated with FIO2 ranging from 0.21 to 1. In all patients, Qsp/Qt decreased when FIO2 was increased from 0.21 to 0.4 and then stabilized to an FIO2 of approximately 0.6. As the FIO2 was increased to 1, Qsp/Qt increased. Since the inhalation of gas mixture with FIO2 greater than or equal to 0.6 increased right-to-left intrapulmonary shunting of blood, we recommend respiratory function be evaluated during inhalation of a clinically useful concentration of O2 rather than at an FIO2 of 1.