Research

Inhaled nitric oxide in persistent pulmonary hypertension of the newborn refractory to high-frequency ventilation

Saleh Al-Alaiyan and Edward Neiley

King Faisal Specialist Hospital and Research Centre, Riyadh, Saudi Arabia

Critical Care 1999, 3:7-10doi:10.1186/cc299

Published:	15 March 1999

Abstract

Background

This study was designed to evaluate the effect of nitric oxide (NO) on the management of neonates with severe persistent pulmonary hypertension refractory to high-frequency oscillatory ventilation.

Methods

The birth weight and the gestational age of infants were 3125.5 ± 794 g (mean ± SD) and 39 ± 2.4 weeks, respectively. All neonates were ventilated for an average of 137.5 min (range 90-180 min) prior to NO therapy. The mean oxygenation index (OI) of all neonates prior to NO was 46.3 ± 5 (mean ± SEM). NO was initially administered at 20 parts per million (ppm) for at least 2 h and increased gradually by 2 ppm to a maximum of 80 ppm.

Results

Eighteen infants (75%) responded and six (25%) did not respond to the treatment. Three neonates died in the responding group, while all the non-responders died (P = 0.0001). The survival rate was 62.5% among all neonates. NO significantly decreased OI (P < 0.0001) and improved the arterial/alveolar (a/A) oxygen ratio (P < 0.0001) within the first 2 h of NO therapy in 61.1% of the responders. However, the OI and the a/A oxygen ratio remained almost the same throughout the treatment in the non-responders and the non-survivors.

Conclusion

Inhaled NO at 20 ppm, following adequate ventilation for 2 h without significant response, could be used to identify the majority of the non-responders in order to seek other alternatives.