Analytic study of pulmonary shunt fraction with changes in inspired oxygen concentration. -Part 2. Comparison of human blood with artificial blood in artificial lung-
Marukawa, S.; Iwai, S.
Masui. Japanese Journal of Anesthesiology 30(8): 782-787
1981
ISSN/ISBN: 0021-4892 PMID: 7321168 Document Number: 178428
To determine the mechanism of the changes in pulmonary shunt fraction with increasing inspired O2 concentration (FIO2), the shunt fraction was studied in an artificial lung to which human stored blood or artificial blood (perfluorochemical blood substitutes: Fluosol-DA) was perfused. Using artificial blood, the shunt fraction in response to increasing FIO2 is constant irrespective of the efficiency of oxygenation in the artificial lung. Using human blood, the change in shunt fraction with increasing FIO2 decreases when PaO2 is < 100 mm Hg; the change increases when PaO2 is > 150 mm Hg. These changes are independent on the efficiency of the artificial lung for oxygenation. Each of these changes represents a part of the previously reported characteristic biphasic pattern. The discrepancies between human and artificial blood may be explained on the basis of O2 affinity of human blood.