Journal of Applied Physiology, Vol 59, Issue 6 1971-1977, Copyright © 1985 by American Physiological Society
Endogenous plasma proteins in edematous lungs and alveolar fluid in rabbits
D. J. Pavlin, R. Haschke, M. L. Nessly and F. W. Cheney
In this study, we compared two methods of differentiating hydrostatic and
permeability types of pulmonary edema. The first method entailed
measurement of protein concentrations directly in samples of alveolar fluid
(AF); the second method was an indirect technique in which protein
concentration in extravascular extracellular water (EVECW) was calculated
on the basis of separate measurements of the quantity of protein in the
lung and the volume of EVECW. The concentration of albumin (Alb) and
gamma-G-globulin was measured in EVECW and alveolar fluid in excised
edematous rabbit lungs. Edema was caused by elevation of left ventricular
end-diastolic pressure to 25 Torr (hydrostatic edema, HE) or by intravenous
oleic acid, 0.09 ml/kg (permeability edema, PE). The volume of distribution
of Na+ was utilized as a measure of EVECW in the lung. Protein
concentration in EVECW and AF relative to plasma (EV/PL and AF/PL,
respectively) was compared in the two types of edema. The EV/PL was 0.61
+/- 0.12 (SD) for Alb in He compared with 1.18 +/- 0.47 in PE (P less than
0.02). The AF/PL was 0.54 +/- 0.12 and 1.25 +/- 0.33 in HE and PE,
respectively (P less than 0.001). There was good correlation between EV/PL
and AF/PL for Alb (r = 0.74, P less than 0.001) but not for
gamma-G-globulin. Thus EV/PL for Alb, AF/PL for Alb, and gamma-G-globulin
all differentiated hydrostatic from permeability edema.
