Nitric oxide therapy for the newborn infant.

Inhaled nitric oxide (INO) is a novel selective pulmonary vasodilator without significant effects on the systemic circulation. Initial case studies of near-term newborn infants with hypoxic respiratory failure and persistent pulmonary hypertension of the newborn showed that INO was associated with improvements in oxygenation. There have now been at least 11 prospective randomized controlled trials evaluating the use of INO in the near-term neonate with hypoxic respiratory failure, 10 of which have been published. A meta-analysis of these trials provides evidence that INO improved the PaO2 in the INO treated infants by 46.4 torr (weighted mean difference) compared with controls (95% CI, 34.2, 58.5) and significantly decreased the oxygenation index by 10.7 compared with controls (95% CI, -14.1, -7.4). The incidence of death or need for extracorporeal membrane oxygenation (ECMO) was significantly reduced by treatment with INO, relative risk (RR) 0.72 compared to control (95% CI, 0.6, 0.87) with the majority of the improvement seen in the reduction in the need for ECMO. Infants with congenital diaphragmatic hernia do not appear to benefit from early INO therapy. The only prospective trials evaluating INO in premature infants to date have not found that this therapy is associated with significant clinical benefit. The long-term evaluations of near-term and full-term infants who have received INO suggest that this therapy does not increase the incidence of adverse neurodevelopmental sequelae in these high-risk infants. INO is an effective therapy for the hypoxic term neonate and will reduce the occurrence of death or the need for ECMO in this population. Further research is required to evaluate the benefit of this therapy in the hypoxic preterm infant.