Inhaled nitric oxide therapy might reduce the need for hyperventilation therapy in infants with persistent pulmonary hypertension of the newborn

Aim: To determine whether inhaled nitric oxide might reduce the need for excessive respiratory alkalosis to maintain systemic oxygenation in infants with persistent pulmonary hypertension of the newborn (PPHN). Materials and methods: A retrospective historical cohort study of 34 infants with PPHN with oxygenation index (OI) of 25 or more, including 19 infants without inhaled nitric oxide (i-NO) therapy (control group) and 15 infants with inhaled nitric oxide therapy (i-NO group) was performed. The initial dose of 10 ppm of i-NO was administered and no responders received the maximum dose of 25 ppm. We evaluated the mortality rate and the change of OI index and PaCO2 during the first 6 days. Results: There were no significant differences in characteristics between groups. Two of 15 in the i-NO group and 6 of 19 infants in the control group died during the first 48 h. Baseline OI, PaCO2 and arterial pH were similar in the two groups. OI in the i-NO group was significantly higher than in the control group between 12 and 96 h. PaCO2 in the i-NO group was higher than in the control group between 24 and 144 h. Conclusion: i-NO therapy for PPHN might improve systemic oxygenation without excessive hypocapnia. However there was no reduction in duration of ventilation support or oxygen supply.