Surfactant and patent ductus arteriosus

Abstract

Objective: To investigate the relationship between surfactant replacement therapy and the development of a haemodynamically significant ductus arteriosus.

Methods: All premature infants at 28-32 wk gestation with a clinical diagnosis of respiratory distress syndrome were retrospectively reviewed and subdivided into two groups; intubated, mechanically ventilated and received surfactant (Group 1); and received nasal continuous positive airway pressure alone (Group 2). The relationship between groups and characteristics of the hemodynamically significant ductus arteriosus was analyzed.

Results: Seventy babies were identified of whom 35 (50%) received surfactant. Babies in group I and II were comparable for gestational age, birthweight, antenatal steroids, gender and fluid intake in first week of life. Babies treated with surfactant therapy were found to be more likely to have a haemodynamically significant ductus arteriosus (p<0.01), larger transductal diameter (p=0.01) and increased rate of therapeutic interventions to close the ductus (p<0.01). Ventilation parameters (mean airway pressure and fractional inspired oxygen) were higher in group I.

Conclusion: Neonates with respiratory distress syndrome (RDS) who were treated with surfactant replacement are at increased risk of a hemodynamically significant ductus arteriosus that requires therapeutic intervention. Whether the relationship reflects their underlying lung disease or is a direct effect of surfactant requires prospective evaluation.