Pulmonary fibroplasia in newborn babies treated with oxygen and artificial ventilation.

A retrospective clinicopathological study was carried out on newborn babies who had died over a 5-year period, had received oxygen therapy, and had lived for 48 hours or longer. 23 of 81 babies had pulmonary fibroplasia at necropsy. Prolonged therapy in oxygen concentrations above 60% and prolonged artificial ventilation were associated with the development of pulmonary fibroplasia. All babies developing pulmonary fibroplasia had been treated in over 60% oxygen for at least 46 hours and the condition was invariably present in those who had over 60% oxygen for more than 123 hours or above 80% oxygen for more than 105 hours. The relation of pulmonary fibroplasia to mechanical ventilation was less constant. Hyaline membrane disease was associated with the development of fibroplasia in babies who lived for 3 days or longer, and the most severe histological changes were almost always associated with HMD. There was no correlation between gestational age and development of pulmonary fibroplasia. It is concluded that oxygen toxicity was probably the most important cause of pulmonary fibroplasia in the babies studied, though some histological features may be more closely related to artificial ventilation. The implications of these findings for oxygen and ventilator therapy in the newborn are discussed.