Aktivitat von superoxiddismutase und katalase im tracheobronchialsekret nach surfactantbehandlung fruhgeborener mit atemnotsyndrom

Oxygen toxicity and mechanical ventilation are main factors in the development of chronic lung disease in preterm infants. We examined two antioxidant enzymes, superoxide dismutase (SOD) and catalase, in tracheal fluid of preterm infants with severe respiratory distress syndrome (RDS) treated with surfactant. SOD and catalase catalyse the transformation of oxygen radicals and hydrogen peroxide to less toxic metabolites. 31 preterm infants were randomised to either single or multiple dose treatment with surfactant (Curosurf®). Tracheal aspirates were obtained during routine tracheal suctioning and the two enzymes were measured during the first week of life. 11 of 31 preterm babies (35%) did not show any SOD-activity in tracheal fluid. Four out of the eleven preterm infants developed bronchopulmonary dysplasia. Patients receiving multiple dose treatment had significantly higher SOD-activity (> 10 μg/mg albumin, p < 0.01) than patients with single dose treatment. Only 2 of 31 preterm babies (6%) lacked catalase activity in tracheal aspirate. 94% had catalase activity between 1 and 12 μg/mg albumin. We conclude that, the majority of preterm infants with severe RDS do not have protective superoxide dismutase activity in tracheal fluid. Following multiple dose surfactant replacement significantly higher SOD activity was observed as compared to single dose therapy.