Pulmonary Hypertension of the Newborn

Persistent pulmonary hypertension of the newborn (PPHN) is characterized by a failure in the transition from fetal to newborn circulation. It is secondary to the persistence of high pulmonary vascular resistance, resulting in extrapulmonary shunting of the blood from pulmonary to systemic circulation and leading to hypoxemia. It is often secondary to respiratory disease, although occasionally, PPHN can present as primary or idiopathic, often associated with “black lungs” on a chest x-ray owing to absence of lung disease and pulmonary oligemia. Neonates with PPHN are often managed using positive pressure ventilation, oxygen to correct hypoxemia, surfactant replacement therapy, vasopressors to maintain systemic pressures, pulmonary vasodilators, and adequate sedation with minimal stimulation. Early surfactant and inhaled nitric oxide can potentially improve oxygenation in PPHN. If hypoxemia is intractable, infants with severe PPHN are placed on extracorporeal membrane oxygenation. This chapter focuses on available evidence to guide management of PPHN.