Journal of Applied Physiology, Vol 51, Issue 2 335-345, Copyright © 1981 by American Physiological Society
Increased pulmonary vascular permeability following acid aspiration
F. A. Grimbert, J. C. Parker and A. E. Taylor
The effect of hydrochloric acid aspiration on transvascular fluid and
protein flux and lung water content was studied in 21 anesthetized dogs. We
measured steady-state lung lymph flow, pulmonary arterial and left atrial
pressures, and the concentration of total protein and albumin in both lymph
and plasma after intratracheal instillation of 2 ml/kg 0.1 N HCl. Acid
injury produced a twofold increase in lung lymph flow and lymph protein
clearance when compared with control. This indicated an increase in
pulmonary microvascular permeability. In dogs given 25 g concentrated human
albumin and 1 mg/kg furosemide 10 min after the acid injury, the
acid-induced increase in fluid filtration was prevented. However, the
decrease in fluid filtration was not attributed to an increase in the
transvascular protein osmotic pressure gradient but to a more direct effect
of furosemide. Treatment with furosemide alone prevented the increase in
lung lymph flow induced by acid injury, whereas albumin alone did not. In
all acid-injured animals there was an increase in lung water when compared
wtih control. Therefore acid aspiration produced localized areas of damage
to filtration vessels that lead to increased leakage of protein and water.
Furosemide treatment prevented much of this increased fluid and protein
flux by an undefined mechanism.
