Tracheal deposition of surfactant before the first breath.

Abstract

Premature rabbit fetuses of gestational age 28 days underwent tracheostomy immediately after delivery, and thus had to take their first breath through a tracheal cannula. in 20 experimental animals, the tracheal tube contained 25 μliter of a concentrated surfactant suspension that had been prepared by centrifugation of alveolar wash from an adult rabbit for 1 hour at 1,000 g and 4° C. in 20 control fetuses, the tracheal tube contained an equal amount of saline or was empty. Thirteen of the fetuses treated with surfactant survived for 3 to 40 hours after the operation, whereas all but one of the control fetuses died within 45 minutes after tracheostomy (P < 0.001). the unopened thorax of each fetus was fixed in formalin, and the air expansion of the lungs was evaluated histologically. Alveolar air expansion, varying in degree from slight to prominent, was apparent in all fetuses treated with surfactant. Among control fetuses, slight alveolar air expansion was observed in 3 cases, whereas in 17, the lungs w...