[Pulmonary surfactant in neonatal pathology].

Following some preliminary remarks on the role of the surfactant in pulmonary physiology and physiopathology, a physiochemical study of the lungs of 26 infants who died in the neonatal period is reported. Two techniques for measuring the decrease in surface tension are set out. The results in the first case (tensiometric method) allow an explanation of the physiopathological aspect of respiratory distress; in the second case (manometric method) the diagrams obtained are characteristic of different clinical states (normal subjects; subjects born prematurely without any hyaline membrane etc...). Furthermore, the second method gives rise to certain hypotheses as to the physiochemical structure of the substances responsible for the tensio-active properties of the surfactant.