Study background and rationale
Respiratory Distress Syndrome (RDS) is a common cause of morbidity and mortality in preterm neonates, especially those <34 weeks of gestation. Though the cases of classical severe Hyaline Membrane Disease (HMD) are seen very less recently with the increasing usage of Antenatal Corticosteroid, a sizable number of preterm neonates do require Surfactant Replacement Therapy despite receiving best of the Delivery room practices including Continuous Positive Airway Pressure (CPAP).
Animal-derived Natural Surfactant preparations are the ones now recommended as standard of care practice for Surfactant replacement therapy in RDS1. Among these, bovine origin surfactant or Beractant (Survanta), Bovine Lung Extract Surfactant – BLES (Neosurf) and Porcine origin surfactant – Poractant α (Curosurf) are available for commercial use in India. There have been a few comparative studies evaluating natural surfactants. Results differ based on comprehensive newborn unit policies used for overall management of RDS. An important study among these, Ramanathan et al. compared the efficacy and safety of poractant alfa and beractant in preterm infants with RDS (3 groups: 100 mg/kg of poractant alfa, 200 mg/kg of poractant alfa, and 100 mg/kg of beractant). Mortality, redosing of surfactant, and oxygen supplements were significantly reduced in the 200 mg/kg of poractant alfa group than in the 100 mg/kg of poractant alfa or beractant groups2. However, it has also been reported that the timing of administration of the surfactant, such as prophylactic versus rescue and early (within 2 hours after birth) versus delayed (later than 2 hours after birth) treatment, is more important than the composition of the surfactant3. A recent meta-analysis in 2019, showed that poractant-α (at 200 mg/kg dose) is associated with better short term respiratory outcomes including lesser combined outcome of BPD/mortality when compared to bovine surfactants at their licensed dose (100 mg/kg) in preterm neonates with RDS4. The pooled analysis also showed an unusually high rate of redosing with bovine surfactant (45% vs 21%) compared to porcine, which is hardly seen in clinical practice. Most of these studies are a decade older, where the practice of antenatal steroids, delivery room CPAP, timing of surfactant, surfactant need (rescue/prophylactic) etc. were still evolving. Higher doses of Poractant- α will also incur higher cost. In contrast to meta-analysis, systematic review of studies of real-world evidence shows similar outcomes in both types of animal derived surfactant.5 Also, there is limited evidence from the Indian subcontinent comparing the animal-derived natural surfactants in their standard prescribed doses in real world scenarios. Hence, the current study was planned to evaluate the effect of surfactant preparations in preterm RDS on various morbidities.