RANDOMIZED, MULTICENTER TRIAL OF INHALED NITRIC OXIDE AND HIGH FREQUENCY OSCILLATORY VENTILATION IN SEVERE PERSISTENT PULMONARY HYPERTENSION OF THE NEWBORN (PPHN). • 1315

To determine the relative roles of high frequency oscillatory ventilation(HFOV) and inhaled nitric oxide (NO) in the treatment of severe PPHN, we enrolled 205 extracorporeal membrane oxygenation (ECMO) candidates in a multicenter clinical trial of HFOV and NO. Patients were stratified by predominant disease category (RDS-diffuse parenchymal disease, N = 70; MAS-meconium aspiration syndrome, N = 58; Other-idiopathic PPHN or non-CDH hypoplasia, N = 43; and CDH-congenital diaphragmatic hernia, N = 34); then randomized to treatment with NO or HFOV. Treatment failure (PaO₂ < 60 mmHg) resulted in crossover to the alternative treatment; treatment failure after crossover allowed combined treatment with HFOV + NO. Baseline oxygenation index and PaO₂ were 48 ± 31(SD) and 42 ± 15(SD) torr respectively, on conventional ventilation. Treatment response was defined as survival to discharge without the need for ECMO with the assigned treatment; cumulative outcomes by category are shown below (% responders). Marked differences in outcomes were noted between centers (% death/ECMO range= 29% - 75%). We conclude that treatment with HFOV + NO is often more succesful than HFOV or NO alone in severe PPHN. Differences in responses are partly related to the specific disease associated with PPHN.Table

Table 1