Continuous, in vivo pulmonary venous admixture from fiberoptically measured hemoglobin saturations.
In six anesthetized swine, pulmonary venous admixture (Qsp/Qt) was calculated by four methods: a) Qsp/Qt 1, fiberoptically measured arterial and mixed venous Hgb saturation (SaO2 and SvO2), PaO2 and PvO2 derived from saturations; b) Qsp/Qt 2, fiberoptically measured SaO2 and SvO2, PaO2 and PvO2 measured by blood gas analysis; c) Qsp/Qt 3, PaO2 and PvO2 measured by blood gas analysis, SaO2 and SvO2 derived from tensions; d) Qsp/Qt 4, SaO2 and SvO2 measured by bench oximetry, PaO2 and PvO2 derived from saturations. Input from the fiberoptic catheters was fed into a computer programmed to calculate Qsp/Qt 1 every 20 sec. Fifty-eight of these values were compared with simultaneously calculated Qsp/Qt 2, 3, and 4. There was no difference between fiberoptic and derived SaO2 or fiberoptic and cooximetric SvO2. Correlations and slopes for Qsp/Qt 1 with Qsp/Qt 2, 3, and 4 were significant (p less than .05). Comparing mean differences, Qsp/Qt 1 was significantly different only from Qsp/Qt 3 (p less than .01). We conclude that dual oximetry reliably tracks Qsp/Qt.
Kamal
G D
GD
Department of Anesthesia, University of Iowa College of Medicine, Iowa City.
Starr
J M
JM
Symreng
T
T
D000818:Animals; D001784:Blood Gas Analysis / Q000592:standards*; D002407:Catheterization, Swan-Ganz; D004195:Disease Models, Animal; D005069:Evaluation Studies as Topic; D005336:Fiber Optic Technology; D006454:Hemoglobins / Q000032:analysis*; D008171:Lung Diseases / Q000097:blood* / Q000139:chemically induced / Q000503:physiopathology; D019301:Oleic Acid; D009829:Oleic Acids / Q000009:adverse effects; D010092:Oximetry / Q000295:instrumentation / Q000379:methods / Q000592:standards*; D010100:Oxygen / Q000097:blood*; D015203:Reproducibility of Results; D013552:Swine
D006454:Hemoglobins; D009829:Oleic Acids; D019301:Oleic Acid; D010100:Oxygen