Impact of early surfactant and inhaled nitric oxide therapies on outcomes in term/late preterm neonates with moderate hypoxic respiratory failure
G G Konduri, G M Sokol, K P Van Meurs, J Singer, N Ambalavanan, T Lee and A Solimano for the Neonatal Inhaled Nitric Oxide Study Group
We conducted a post-hoc analysis of early inhaled nitric oxide (iNO)-randomized controlled trial data to identify associations pertinent to the management of moderate hypoxic respiratory failure in term/late preterm infants.
Univariate and multivariate logistic regression analyses were used to determine risk factors for the progression of respiratory failure and extracorporeal membrane oxygenation (ECMO)/death.
Among the 299 enrolled infants, oxygenation index (OI) <20 at enrollment (odds ratio 0.52, confidence interval (CI) 0.27 to 0.97) and surfactant use before randomization (odds ratio 0.47, CI 0.24 to 0.91) were associated with decreased ECMO/death rates. Early surfactant use for respiratory distress syndrome, perinatal aspiration syndrome and pneumonia/sepsis was associated with lower risk of ECMO/death (P<0.001). Early iNO (OI 15 to 25) decreased the progression of respiratory failure to OI >30 (P=0.002) and to composite outcome of OI >30 or ECMO/death (P=0.02).
This post-hoc analysis suggests that early use of surfactant and iNO in moderate respiratory failure is associated with improved outcomes.
This is a post-hoc analysis of the early iNO trial reported by Konduri in 2004. With that in mind, I believe the findings confirm other study results. Earlier initiation of iNO (OI<20 compared to OI 20-25) reduced the rate of ECMO/death and shortened the length of stay. Also, initiation of iNO at an OI of 15-25 (compared to >25) was associated with decreased progression to OI≥30 and/or ECMO/death. Notably, early surfactant therapy for infants with parenchymal lung disease was associated with a threefold reduction in the risk of ECMO/death, and it was most beneficial in an OI range of 15-23. Since study infants had an enrollment FiO2 requirement of >0.8, it remains to be seen if infants on lower FiO2 but higher MAPs would show the same benefit. Currently, early surfactant replacement and iNO should remain routine therapies in term and near term infants with HRF due to parenchymal lung disease.
Victor McKay, M.D.