LUNG EDEMA FORMATION FOLLOWING INHALATION INJURY - ROLE OF THE BRONCHIAL BLOOD-FLOW

We investigated the contribution of the bronchial blood flow to the lung lymph flow (Q(L)) and lung edema formation after inhalation injury in sheep (n = 18). The animals were equally divided into three groups and chronically prepared by implantation of cardiopulmonary catheters and a flow probe on the common bronchial artery. Groups 1 and 2 sheep were insufflated with 48 breaths of cotton smoke while group 3 received only room air. Just before injury, the bronchial artery of group 2 animals was occluded. The occlusion was maintained for the duration of the 24-h study period. At the end of the investigation, samples of lung were taken for determination of blood-free wet weight-to-dry weight ratio (W/D). Inhalation injury induced a sevenfold increase in Q(L) in group 1 (7 +/- 1 to 50 +/- 9 ml/h; P < 0.05) but only a threefold increase in group 2 (10 +/- 2 to 28 +/- 7 ml/h; P < 0.05). The mean W/D value of group 1 animals was 23% higher than that of group 2 (5.1 +/- 0.4 vs. 3.9 +/- 0.2; P < 0.05). Our data suggest that the bronchial circulation contributes to edema formation in the lung that is often seen after the acute lung injury with smoke inhalation.