Effect of the mode of extrapulmonary gas exchange on the function and metabolism of pulmonary surfactant

: The peculiarities of the functional state of lung surfactant as well as the character and degree of disorders in its phospholipid metabolism during venoarterial perfusion and extrapulmonary 120-min oxygenation carried out with the help of contact-type (foam-film) and membrane ("Sever") oxygenators were studied in 28 experimental dogs. It was shown that the functional state and phospholipid metabolism of lung surfactant were strongly dependent on the mode of extrapulmonary gas exchange (the type of oxygenator). Membrane oxygenation is more physiological than contact-type gas exchange. The rise in ST min of bronchoalveolar wash-outs with the application of foam-film oxygenator to 25 mN/m and above is caused by disorders in phospholipid metabolism of lung surfactant. It is manifested in the decrease of phosphatidylcholine content, the increase in sphingomyelin, the appearance of lysophosphatidylcholine fraction and the decrease in phosphatidylcholine/sphingomyelin ratio.