Effect of hemorrhagic shock on pulmonary transvascular fluid and protein exchange in anesthetized dogs.

We demonstrated the effect of hemorrhagic shock with resuscitation on pulmonary fluid and protein exchange in anesthetized dogs. Lung lymph flow decreased during early shock and then increased gradually to baseline during late shock as the pulmonary vascular pressures reverted toward baseline levels, while the lymph-to-plasma protein ratio remained relatively constant throughout the shock period. During resuscitation, lung lymph flow increased significantly with the decreasing lymph:plasma protein ratio, suggesting no change in permeability to proteins. Lymph protein flow, which is characteristic of increased endothelial permeability, was also not altered during resuscitation, compared to that following increased vascular pressure induced by inflation of a left atrial balloon catheter. These findings suggest that no change in pulmonary vascular permeability occurs in anesthetized dogs after hemorrhagic shock with resuscitation.