Pulmonary hypertension in preterm infants is defined by the same guidelines used for adults and children: mean pulmonary arterial pressure =20 mm Hg, pulmonary capillary wedge pressure <15 mm Hg, and indexed pulmonary vascular resistance >3 Wood units/m2. Bronchopulmonary dysplasia, the major cause of chronic lung disease in preterm infants, is defined as the need for oxygen at 36 weeks postconceptual age in infants born at or before 32 weeks’ gestation. The disruption of growth and function of the pulmonary vasculature observed with bronchopulmonary dysplasia contributes to the development of pulmonary hypertension. Abnormal pulmonary vasculature develops increased pulmonary vascular resistance and mean pulmonary artery pressures. As many of 20%–40% of patients with bronchopulmonary dysplasia have persistent pulmonary hypertension and the combination is accompanied by significant morbidity and mortality. This chapter details the assessment and perioperative considerations involved in caring for a preterm infant with these conditions undergoing multiple surgical procedures.

Idiopathic pulmonary arterial hypertension is a subset of pulmonary hypertension in which progressive narrowing of pulmonary vasculature leads to an increase in pulmonary vascular resistance and eventual right ventricular failure. Survival and quality of life have significantly improved with the advent of targeted therapies that promote pulmonary vasodilation and improve right ventricular function. Children with pulmonary hypertension have a 20-fold higher incidence of perioperative cardiac arrest compared to the general pediatric population. A well-balanced, hemodynamically stable anesthetic that aims to avoid increases in pulmonary vascular resistance and decreases in ventricular function or coronary perfusion is crucial in preventing a pulmonary hypertensive crisis. The anesthetist must anticipate, rapidly recognize, and treat impending signs of pulmonary hypertensive crisis in order to safely anesthetize a child with pulmonary hypertension.

In this chapter, the author discussed the pathophysiology and diagnosis of pulmonary hypertension. The major classifications of pulmonary hypertension are reviewed as well as the current medical management options by pathway effected. The Electrocardiographic and echocardiographic findings in pulmonary hypertension are discussed in relation to severity of illness. The anesthetic considerations necessary in patients with severe pulmonary hypertension are presented.