Nitric oxide is superior to prostacyclin for pulmonary hypertension after cardiac operations.

BACKGROUND

Severe pulmonary hypertension is still a cause of morbidity and mortality in children after cardiac operations. The objective of this study was to compare the vasodilator properties of inhaled nitric oxide, a novel pulmonary vasodilator, and intravenous prostacyclin in the treatment of severe postoperative pulmonary hypertension.

METHODS

Thirteen children (aged 3 days to 12 months) with severe pulmonary hypertension after cardiac operations were given inhaled nitric oxide (20 ppm x 10 minutes) and intravenous prostacyclin (20 ng.kg-1.min-1 x 10 minutes) in a prospective, randomized cross-over study.

RESULTS

Both nitric oxide and prostacyclin resulted in a reduction in pulmonary arterial pressure, although the mean pulmonary arterial pressure was significantly lower during nitric oxide therapy (28.5 +/- 2.9 mm Hg) than during prostacyclin therapy (35.4 +/- 2.1 mm Hg; p < 0.05). The mean pulmonary to systemic arterial pressure ratio was also significantly lower during nitric oxide than prostacylin administration (0.46 +/- 0.04 versus 0.68 +/- 0.05; p < 0.01), due mainly to only prostacyclin lowering systemic blood pressure.

CONCLUSIONS

Inhaled nitric oxide was a more effective and selective pulmonary vasodilator than prostacyclin and should be considered as the preferred treatment for severe postoperative pulmonary hypertension.