Is sildenafil an effective therapy in the management of persistent pulmonary hypertension?

Persistent pulmonary hypertension of the newborn (PPHN) is a life-threatening neonatal pathology resulting from poor hemodynamic and respiratory transition to extra uterine life. Inhaled nitric oxide (iNO) is a current, commonly used treatment of PPHN. However, iNO is not available therapy in many developing countries and around 50% of infants with PPHN do not respond to iNO therapy. Sildenafil is a phosphodiesterase inhibitor type 5 (PDE5) that has been shown to selectively reduce pulmonary vascular resistance in both animal models and adult humans. Recent studies have found that in PPHN, administration of Sildenafil was associated with a significant increase in the oxygenation and a reduction in mortality with no clinically important side effects.