Findings on chest radiographs after prophylactic pulmonary surfactant treatment of premature infants.

Clinical trials are underway that use pulmonary surfactant replacement therapy in an attempt to prevent respiratory distress syndrome (RDS) in premature infants. This study was undertaken to determine the relationship between the clinical course of infants receiving prophylactic "first-breath" endotracheal surfactant and their initial posttreatment radiographs. The study population consisted of 80 premature infants of 24-32 weeks gestational age. All received 3 ml of calf-lung surfactant extract via endotracheal tube at birth. Anteroposterior chest radiographs taken within 1 hr of treatment were reviewed and correlated with gestational age, birth weight, days of endotracheal intubation, mean airway pressure, and days of oxygen requirement greater than 30%. Three distinct patterns of radiographic abnormality were encountered: typical RDS with hypoinflation, diffuse granularity, and air bronchograms (30%); central clearing of RDS (14%); and disproportionate clearing of RDS in the right lung (8%). No significant differences in ventilator requirements or clinical course were seen among these three groups. A fourth group (49%), whose posttreatment radiographs showed no evidence of RDS, required significantly less ventilatory support. Prophylactic first-breath surfactant treatment of premature infants occasionally results in radiographic patterns that are atypical for RDS. Familiarity with these patterns and their clinical significance will be important if surfactant augmentation becomes prevalent.