Blood flow in pulmonary and bronchial arteries in acute experimental pneumonia and pulmonary embolism.

Acute lobar pneumonia and pulmonary embolism were induced in rabbits and the blood flow in the pulmonary artery and bronchial arteries was determined using isotopic microspheres. In acute pneumonia the pulmonary artery flow to the involved lung was reduced 8.5 times and the bronchial artery flow was reduced 5.0 times compared to flow in the normal lung. In acute pulmonary embolism, both the pulmonary artery flow (2.3 times) and the bronchial artery flow (2.5 times) were also reduced. For all animals, the reduction in pulmonary artery flow paralleled the reduction in bronchial artery flow (r=0.65).