Complications of Surfactant Treatment in Late Preterm Infants with Respiratory Distress Syndrome

Abstract

Respiratory distress syndrome remains a common cause of morbidity in late preterm infants due to surfactant deficiency and immature lung function. Surfactant therapy administered via minimally invasive techniques has improved respiratory outcomes; however, early complications may still occur. Objective: To determine the frequency of early complications following surfactant therapy in late preterm infants with respiratory distress syndrome. Methods: A prospective observational study was conducted at the Department of Paediatrics, Arif Memorial Teaching Hospital, Lahore, from 3rd June 2025 to 3rd November 2025. A total of 111 late preterm infants with gestational age between 32 and 36 weeks diagnosed with respiratory distress syndrome and requiring surfactant therapy were enrolled through non-probability consecutive sampling. Surfactant was administered using the minimally invasive surfactant therapy technique while maintaining continuous positive airway pressure support. Early complications occurring within 24 hours after surfactant administration were recorded, including pulmonary haemorrhage, bradycardia, tachycardia, need for mechanical ventilation, requirement of a second dose of surfactant, and mortality. Data were entered and analyzed using SPSS version 25. Stratification was performed to control potential effect modifiers such as gestational age and birth weight. Associations were assessed using the Chi-square test, with a p-value ≤0.05 considered statistically significant. Results: The mean gestational age of the neonates was 34.1 ± 1.2 weeks, and the mean birth weight was 2145 ± 320 grams. Mechanical ventilation was required in 23.4% of infants. Early complications included pulmonary hemorrhage in 16.2% of neonates, bradycardia in 8.1%, and tachycardia in 4.5%. A second dose of surfactant was required in 33.3% of cases. Overall mortality was observed in 15.3% of neonates. Early complications were significantly more frequent among infants with gestational age 32–33 weeks compared with those aged 34–36+6 weeks (p < 0.001). Conclusion: Late preterm infants remain at risk of respiratory complications despite receiving surfactant therapy. Infants with lower gestational age within the late preterm range tend to experience a higher frequency of early complications. Standardized treatment protocols and larger multicenter studies may help improve the safety and effectiveness of surfactant therapy in this population.