Morphology of the microvascular system in shock: lung, liver, and skeletal muscles.

We used a standardized canine polytrauma model (bone fracture, soft-tissue injury, and hypovolemia), either with or without reinfusion, to study granulocyte accumulation in lung, liver, and muscle tissue. Infusion of radioactively labeled granulocytes revealed significant leukostasis in the lung after the shock procedure, which was more prominent in the group without reinfusion. There was only moderate leukostasis in the liver, while granulocytes were absent from muscle tissue. These radioactive data were in good agreement with the morphologic findings of electron microscopy. Thus, although there was capillary endothelial swelling in all three organs, edema in the muscle endothelial cells of reperfused animals was not due to granulocyte action.