Practices and Outcomes from a Prospective, Multicenter Registry for Preterm Newborns with Pulmonary Hypertension

Abstract

To describe current treatment practices of preterm infants with early hypoxemic respiratory failure (HRF) and pulmonary hypertension (PH) and their association with patient outcomes. We developed a prospective, observational, multicenter clinical registry of preterm newborns <34weeks' gestation with HRF and PH, based on either clinical or echocardiographic evidence during the first 72hours of life, from 28 neonatal intensive care units in the US from 2017 through 2022. The primary end point was mortality among those who did or did not receive PH-targeted treatment, and the secondary end points included comparisons of major morbidities. Variables were compared using t tests, Wilcoxon rank-sum tests, Fisher exact tests, and χ² tests. We analyzed the results of 224 preterm infants enrolled in the registry. Of which, 84% (188/224) received PH-targeted treatment, most commonly inhaled nitric oxide (iNO). Early mortality in this cohort was high, as 33% (71/224) of this sample died in the first month of life, and 77% of survivors (105/137) developed bronchopulmonary dysplasia. Infants who received PH-targeted treatment had higher oxygenation indices at the time of enrollment (28.16 [IQR: 13.94, 42.5] vs 15.46 [IQR: 11.94, 26.15]; P=.0064). Patient outcomes did not differ between those who did or did not receive PH-targeted therapy. Early-onset HRF with PH in preterm infants is associated with a high early mortality and a high risk of developing bronchopulmonary dysplasia. iNO is commonly used to treat early-onset PH in preterm infants with HRF. In comparison with untreated infants with lower oxygenation indices, iNO treatment in severe PH may prevent poorer outcomes.