Surfactant status and respiratory outcome in premature infants receiving late surfactant treatment.
DOI: 10.1038/s41390-018-0144-3; PMCID: PMC6377352
BACKGROUND: Many premature infants with respiratory failure are deficient in surfactant, but the relationship to occurrence of bronchopulmonary dysplasia (BPD) is uncertain.
METHODS: Tracheal aspirates were collected from 209 treated and control infants enrolled at 7-14 days in the Trial of Late Surfactant. The content of phospholipid, surfactant protein B, and total protein were determined in large aggregate (active) surfactant.
RESULTS: At 24 h, surfactant treatment transiently increased surfactant protein B content (70%, p < 0.01), but did not affect recovered airway surfactant or total protein/phospholipid. The level of recovered surfactant during dosing was directly associated with content of surfactant protein B (r = 0.50, p < 0.00001) and inversely related to total protein (r = 0.39, p < 0.0001). For all infants, occurrence of BPD was associated with lower levels of recovered large aggregate surfactant, higher protein content, and lower SP-B levels. Tracheal aspirates with lower amounts of recovered surfactant had an increased proportion of small vesicle (inactive) surfactant.
CONCLUSIONS: We conclude that many intubated premature infants are deficient in active surfactant, in part due to increased intra-alveolar metabolism, low SP-B content, and protein inhibition, and that the severity of this deficit is predictive of BPD. Late surfactant treatment at the frequency used did not provide a sustained increase in airway surfactant.
Birth Weight; Bronchopulmonary Dysplasia; Drug Administration Schedule; Female; Humans; Infant; Infant, Newborn; Infant, Premature; Infant, Premature, Diseases; Male; Phospholipids; Pulmonary Surfactant-Associated Protein B; Pulmonary Surfactants; Respiration
Birth Weight; Bronchopulmonary Dysplasia; Drug Administration Schedule; Phospholipids; Pulmonary Surfactant-Associated Protein B; Pulmonary Surfactants; Respiration
Ballard PL, Keller RL, Truog WE, et al. Surfactant status and respiratory outcome in premature infants receiving late surfactant treatment. Pediatr Res. 2019;85(3):305-311. doi:10.1038/s41390-018-0144-3