Optical measurement of isolated canine lung filtration coefficients at normal hematocrits

• Published in: Journal of applied physiology (1985) 1997-12, Vol.83 (6), p.1976-1985
• Main Authors: Klaesner, Joseph W, Pou, N. Adrienne, Parker, Richard E, Finney, Charlene, Roselli, Robert J
• Format: Article
• Language: English
• Subjects: Air breathing; Animals; Biological and medical sciences; Blood Pressure - physiology; Blood Volume - physiology; Diffusion; Dogs; Extravascular Lung Water - physiology; Fundamental and applied biological sciences. Psychology; Hematocrit; Indicator Dilution Techniques; Lung - metabolism; Lung - physiology; Permeability; Pulmonary Circulation - physiology; Respiratory system: anatomy, metabolism, gas exchange, ventilatory mechanics, respiratory hemodynamics; Vertebrates: respiratory system
• ISSN: 8750-7587; 1522-1601
• DOI: 10.1152/jappl.1997.83.6.1976

Joseph W. Klaesner 1 , N. Adrienne Pou 2 , Richard E. Parker 2 , Charlene Finney 2 , and Robert J. Roselli 1 1  Department of Biomedical Engineering and 2  Center for Pulmonary Research, Vanderbilt University, Nashville, Tennessee 37235 Received 25 September 1996; accepted in final form 14 August 1997. Klaesner, Joseph W., N. Adrienne Pou, Richard E. Parker, Charlene Finney, and Robert J. Roselli. Optical measurement of isolated canine lung filtration coefficients at normal hematocrits. J. Appl. Physiol. 83(6): 1976-1985, 1997. In this study, lung filtration coefficient ( K fc ) values were measured in eight isolated canine lung preparations at normal hematocrit values using three methods: gravimetric, blood-corrected gravimetric, and optical. The lungs were kept in zone 3 conditions and subjected to an average venous pressure increase of 10.24 ± 0.27 (SE) cmH 2 O. The resulting K fc (ml · min 1 · cmH 2 O 1 · 100 g dry lung wt 1 ) measured with the gravimetric technique was 0.420 ± 0.017, which was statistically different from the K fc measured by the blood-corrected gravimetric method (0.273 ± 0.018) or the product of the reflection coefficient ( f ) and K fc measured optically (0.272 ± 0.018). The optical method involved the use of a Cellco filter cartridge to separate red blood cells from plasma, which allowed measurement of the concentration of the tracer in plasma at normal hematocrits (34 ± 1.5). The permeability-surface area product was measured using radioactive multiple indicator-dilution methods before, during, and after venous pressure elevations. Results showed that the surface area of the lung did not change significantly during the measurement of K fc . These studies suggest that f K fc can be measured optically at normal hematocrits, that this measurement is not influenced by blood volume changes that occur during the measurement, and that the optical f K fc agrees with the K fc obtained via the blood-corrected gravimetric method. Evans blue; pulmonary vascular volume 0161-7567/97 $5.00 Copyright © 1997 the American Physiological Society