Nitric oxide (NO) was administered to an infant in a near fatal crisis of pulmonary hypertension after total correction of double outlet right ventricle. Inhaled NO of 4 parts per million reduced pulmonary arterial pressure (PAP) and increased tidal volume during pressure limit ventilation. Both respiratory system compliance and resistance were improved with NO inhalation. There was a significant negative correlation between mean PAP and respiratory system compliance. We speculated that a reduction in PAP with NO inhalation resulted in the improvement of respiratory function. He was successfully weaned from mechanical ventilation.