Alternative routes of surfactant application - An update

Non-invasive respiratory support paired with minimally invasive surfactant therapy in preterm infants

Non-invasive ventilation (NIV) commenced soon after birth is highly effective in providing mechanical respiratory support for preterm infants with respiratory distress syndrome (RDS). However, NIV alone frequently fails to provide adequate respiratory support for infants with more significant respiratory compromise due to RDS. Without an endotracheal tube as the conduit to administer exogenous surfactant in such cases, less invasive approaches to surfactant delivery have emerged, with those involving the use of a thin catheter (termed minimally invasive surfactant therapy, MIST) now in the ascendancy. The application of MIST with NIV support continuing allows spontaneous breathing to be harnessed for optimal surfactant dispersal to the distal airspaces. Here we examine the importance of this pairing of NIV with MIST and review the evidence for optimization of NIV before, during and after delivery of surfactant. All evidence points to NIV and MIST being an elegant and synergistic pairing of two therapies for optimal respiratory support of preterm infants in early life. Whilst much of the clinical trial data regarding the pairing of NIV and MIST relates to application of standard continuous positive airway pressure, non-invasive positive pressure ventilation in its various forms may offer additional advantage, and further studies are warranted.

Non-invasive versus invasive respiratory support in preterm infants

Respiratory insufficiency is almost ubiquitous in infants born preterm, with its incidence increasing with lower gestational age. A wide range of respiratory support management strategies are available for these infants, separable into non-invasive and invasive forms of respiratory support. Here we review the history and evolution of respiratory care for the preterm infant and then examine evidence that has emerged to support a non-invasive approach to respiratory management where able. Continuous positive airway pressure (CPAP) is the non-invasive respiratory support mode currently with the most evidence for benefit. CPAP can be delivered safely and effectively and can commence in the delivery room. Particularly in early life, time spent on non-invasive respiratory support, avoiding intubation and mechanical ventilation, affords benefit for the preterm infant by virtue of a lessening of lung injury and hence a reduction in incidence of bronchopulmonary dysplasia. In recent years, enthusiasm for application of non-invasive support has been further bolstered by new techniques for administration of exogenous surfactant. Methods of less invasive surfactant delivery, in particular with a thin catheter, have allowed neonatologists to administer surfactant without resort to endotracheal intubation. The benefits of this approach appear to be sustained, even in those infants subsequently requiring mechanical ventilation. This cements the notion that any reduction in exposure to mechanical ventilation leads to alleviation of injury to the vulnerable preterm lung, with a long-lasting effect. Despite the clear advantages of non-invasive respiratory support, there will continue to be a role for intubation and mechanical ventilation in some preterm infants, particularly for those born <25 weeks' gestation. It is currently unclear what role early non-invasive support has in this special population, with more studies required.