Abstract : We developed a new modality of broncho-alveolar lavage technique to measure repeatedly (every 15 min. during 4 hours), the capillary-alveolar permeability to a macromolecule (FITC-dextran). After an oleic acid lung injury, capillary-alveolar permeability to FITC-dextran reaches a peak within 30 minutes. Thereafter the permeability decreases slowly until the end of the experiment.
We assessed the effects of terbutaline, a β2-agonist assumed to reduce in vitro the microvascular permeability in acute lung injury. Terbutaline infusion started 10 min. after oleic acid injury did not change the time course of permeability. Terbutaline infusion started 90 min. after injury interrupted the recovery with an aggravation in permeability. As cardiac index and pulmonary capillary pressure increased with terbutaline infusion, we speculate that terbutaline recruits leaky capillaries and increases FITC-dextran permeability during late recovery from oleic acid injury.