Surfactant quantity and composition during recovery from hyaline membrane disease

The appearance of phosphatidylglycerol in the tracheal wash of infants with hyaline membrane disease (HMD) has been reported to be associated with clinical signs of recovery. We analyzed lung tissue and bronchoalveolar lavage surfactant in an animal model of HMD to determine whether phosphatidylglycerol or some other component is necessary for recovery. The amount and composition of phospholipid (PL) was determined in the premature Macaca nemestrina monkey (140 days' gestation) during an acute stage of HMD, and in two stages of recovery. These changes were compared to observations made in healthy premature controls (140 days), gestational age-matched fetuses (140 days), and fetuses of 150 days' gestation (term = 168 days). The amount of PL and its surfactant composition in lung homogenates of the right lower lobe and in lavage of the excised left lung was determined. Compared to 140-day fetuses, the healthy controls had a several-fold increase in lavage PL and disaturated phosphatidylcholine (DSPC) during the first few days of life (p less than 0.05). Prior to recovery, animals with HMD had no such increase in lavage PL or DSPC and demonstrated poor deflation stability. Recovery was associated with increased tissue and lavage PL (p less than 0.05) and increased fractions of phosphatidylinositol and DSPC (p less than 0.05), but not phosphatidylglycerol. The tissue compositional changes observed during recovery reflected maturational changes observed in the fetal animals studied at 10 days' greater gestational age.(ABSTRACT TRUNCATED AT 250 WORDS)