There is a lack of consensus on the role of inhaled nitric oxide (iNO) therapy and other pulmonary vasodilators for the treatment of severe pulmonary hypertension (PH) in premature newborns (\<34 weeks gestation). However, a proper randomized, controlled trial of iNO in premature newborns with severe PH has not been completed. Some practices embrace the American Academy of Pediatrics (AAP) statement that there is no condition for which iNO should be used in the premature newborn, and others selectively treat premature infants with inhaled nitric oxide (iNO) who suffer life threatening hypoxemia due to suprasystemic PH and right-to-left veno-arterial admixture across the arterial duct and/or oval foramen. The number of neonatal intensive care units (NICUs) adopting each of these approaches is currently unknown, but it is possible that the former group is increasing due to administrative pressure to reduce uncompensated off-label iNO use. A prospective registry collection of treatment strategies and outcomes for this subset of premature newborns will help define current treatment strategies and yield important information about safety and efficacy of the different approaches to management, and would inform the debate more effectively than a series of iNO treated infants alone. Data collected includes maternal age, race/ethnicity, pregnancy and delivery complications, prenatal medications, infant characteristics such as Apgar scores, birthweight, congenital anomalies, respiratory status, pharmacologic therapy used for PH and its side effects, and blood gas data. Up to 100 sites in North America will be invited to monitor for appropriate cases.
