Extracorporeal blood treatment with an ozone-oxygen mixture increased the efficacy of pulmonary ventilation and improved gas exchange, blood oxygenation in the pulmonary circulation, and the microcirculation in peripheral tissues in intact dogs and dogs with experimentally produced shock lung. This procedure activated glycogenolysis, glycolysis, and metabolic processes in the lung tissue (in particular, the uptake of palmitate from the blood by the lungs was increased in intact dog.s, as was the uptake of lactate and pyruvate in dogs with shock lung), and it also raised blood levels of molecular lipid peroxidation products in dogs of both groups.