Lung function and morphology after hemorrhagic shock, soft tissue trauma and regional ischemia in dogs.

Among 40 dogs submitted to 1 of 3 experimental shock procedures: hemorrhagic shock, soft tissue trauma or regional ischemia, 24 dogs fulfilled the criteria of irreversible shock, based on survival or characteristic hemodynamic and metabolic changes. The 24 dogs were studied by measurements of lung function and hemodynamics. During the shock period no impairment of lung function was observed. The pulmonary shunting ratio fell and pulmonary vascular resistance increased. The macroscopical aspect of the lungs did not differ from that of 10 control dogs. The microscopical examination of the lungs, performed after infusion fixation, revealed only a higher granulocyte infiltration in traumatic shock and more severe congestion in hemorrhagic shock.