Journal of Applied Physiology, Vol 77, Issue 1 352-356, Copyright © 1994 by American Physiological Society
Tracheal mucosal edema in hydrostatic pulmonary edema
H. Baier, D. Onorato, J. Barker and A. Wanner
Pulmonary Division, University of Miami School of Medicine, Florida 33101.
Airway edema has been described in heart failure, and, in animal
experiments, airway narrowing was observed with elevated left atrial
pressure (Pla). On the basis of double-indicator-dilution principles using
helium and dimethylether, we were able to measure a water compartment of
the tracheal mucosa (VH2O) in dogs. Hypervolemia with an attendant increase
in Pla caused by infusion of 2 liters of dextran increased VH2O from 368
+/- 71 (SE) to 794 +/- 177 microliters (P < 0.01). Pulmonary arterial
wedge and central venous pressures (Pcv) rose concomitantly. Increases in
pulmonary arterial wedge and Pcv by a left atrial balloon catheter produced
similar increases in VH2O, whereas increases in Pcv alone by a right atrial
balloon did not increase VH2O. Increasing VH2O by dextran infusion was
associated with an increase in pulmonary resistance from 1.16 +/- 0.19 to
2.15 +/- 0.24 cmH2O.l-1.s (P < 0.01). These observations show that fluid
accumulation in the lung during pulmonary congestion also involves
extraparenchymal airways and is related to Pla rather than right atrial
pressure. This indicates that sufficient collateral drainage exists during
right-sided but not left-sided pressure elevations.
