Surfactant for Neonatal Respiratory Distress Syndrome(NRDS) and Neonatal Acute Respiratory Distress Syndrome(NARDS)

In preterm infants with neonatal respiratory distress syndrome (NRDS), exogenous pulmonary surfactant(PS) replacement therapy is one of the most important therapeutic breakthrough to reduce neonatal mortality. Nowadays, PS is commonly used in newborn infants with respiratory distress, but the incidences of bronchopulmonary dysplasia(BPD) and/or death are inconsistent. The result indicates that not all preterm infants with respiratory distress can be beneficial from PS. In 2017, the international neonatal ARDS (NARDS) collaborative group provides the first consensus definition for NARDS. And whether or not PS being beneficial for preterm infants with NARDS remains unknown.

To date, PS is not recommended to adult and pediatric ARDS. Meantime, systematic review indicates that PS does not demonstrate statistically significant beneficial effects on reducing the mortality and the rate of BPD in term and late preterm infants with meconium aspiration syndrome(MAS). Therefore, a reasonable speculation is that preterm infants with NARDS do not benefit from one dose of PS. And the speculation can explain why not all preterm infants with respiratory distress can be beneficial from PS. In the era of pre-NARDS, the preterm infants fulfilling the definition of NARDS may have been considered as NRDS in the first three days after birth. According to the diagnostic criteria of NARDS, a key procedure for diagnosis of NARDS is to exclude the newborn infants with NRDS. But no detailed procedures are available to differentiate NRDS from NARDS.