Developmental outcomes in persistent pulmonary hypertension treated with nitric oxide therapy

Background:  The aim of the present study was to assess 3 year auditory and neurodevelopmental outcomes of persistent pulmonary hypertension of the newborn (PPHN) before and after introducing inhaled nitric oxide (i-NO) therapy, and to detect the clinical factors affecting poor outcome.
Methods:  A retrospective historical cohort study of 26 survivors with PPHN with oxygenation index (OI) ≥25 (13 infants without i-NO therapy, control group; 13 with i-NO therapy, i-NO group) was performed. Auditory brainstem response (ABR) at 6 and 12 months and neurodevelopmental outcomes at 3 years of age were evaluated.
Results:  ABR abnormalities at 6 months were observed in one infant in the i-NO group and six in the control group ( P  = 0.04). At 1 year, one infant in the i-NO group and two of six infants in the control group still had ABR abnormality. In the i-NO group, two children had abnormal neurodevelopmental outcomes, as compared with five children in the control group at 3 year follow up. Two children in the control group and no children in the i-NO group had hearing loss at 3 years of age. Hypocapnea ( P  = 0.04) and elevated creatine phosphokinase ( P  = 0.04) were found to be most predictive for neurodevelopmental abnormality.
Conclusion:  Avoidance of excessive hypocapnea via introduction of i-NO therapy might reduce both ABR and neurodevelopmental abnormalities.