Surfactant Replacement Therapy in Preterm Infants

Introduction to Surfactant Replacement Therapy

• Surfactant replacement therapy significantly reduces mortality, air leaks, and severity of respiratory distress syndrome in preterm infants with surfactant deficiency, and should be administered as soon as possible after intubation regardless of antenatal steroid exposure or gestational age 1, 2, 3

Benefits of Surfactant Replacement Therapy

• Surfactant replacement therapy has been proven to reduce mortality (RR: 0.63, 95% CI: 0.47 to 0.84), pneumothorax (RR: 0.62, 95% CI: 0.42 to 0.89), pulmonary interstitial emphysema (RR: 0.54, 95% CI: 0.36 to 0.82), and combined outcome of bronchopulmonary dysplasia and death (RR: 0.85, 95% CI: 0.76 to 0.95) 4

Prophylactic vs. Rescue Surfactant Administration

• Prophylactic surfactant (administered before onset of respiratory symptoms, within 10-30 minutes after birth) is beneficial for extremely preterm infants at high risk of RDS, especially those without antenatal steroid exposure 2, 3
• Early rescue surfactant (within 1-2 hours of birth) is superior to late rescue surfactant (≥2 hours after birth) in reducing adverse respiratory outcomes in infants <30 weeks' gestation 1, 5

Types of Surfactant and Administration Techniques

• Both animal-derived (natural) and synthetic surfactants decrease respiratory morbidity and mortality in preterm infants with surfactant deficiency 1, 5, 2
• Newer synthetic surfactants with surfactant protein-like activity show promise as treatments for surfactant deficiency disorders 1, 5, 2

Impact on Complications of Prematurity

• Surfactant therapy reduces the combined outcome of death or bronchopulmonary dysplasia compared to no surfactant replacement 4, 7
• The incidence of BPD is lower in treated infants born at ≥30 weeks' gestation compared with untreated infants of the same gestational age 1, 5, 2

Synergy with Antenatal Steroids

• Antenatal steroids and postnatal surfactant replacement independently and additively reduce mortality, severity of RDS, and air leaks in preterm infants 1, 7, 2
• Antenatal steroids may reduce the need for prophylactic and early rescue surfactant replacement in infants born after 27-28 weeks' gestation 7, 2

Clinical Implications and Emerging Approaches

• Surfactant should be administered as soon as possible after intubation in infants with RDS, regardless of gestational age or antenatal steroid exposure 2, 3
• Continuous positive airway pressure (CPAP) with or without surfactant may reduce the need for additional surfactant and incidence of bronchopulmonary dysplasia 1, 5, 7, 2