Perioperative complications in children with pulmonary hypertension undergoing noncardiac surgery or cardiac catheterization.

Pulmonary arterial hypertension (PAH) is defined as the presence of a mean pulmonary artery pressure (PAP) that exceeds 25 mm Hg at rest or 30 mm Hg during exercise. PAH can be idiopathic (primary) or associated with a variety of underlying causes (1–3). Patients with PAH are generally considered to be at greater risk for the development of life-threatening perioperative cardiovascular complications. Increases in pulmonary vascular resistance (PVR) will increase right ventricular afterload, and can lead to right ventricular dysfunction. A potentially fatal complication is a pulmonary hypertensive crisis, characterized by a rapid increase in PVR to the point where PAP exceeds systemic blood pressure (BP). The resulting right heart failure leads to a decrease in pulmonary blood flow, decreased cardiac output, hypoxia, and biventricular failure (4). Other perioperative mechanisms associated with right-sided heart failure in patients with PAH include hypovolemia (inadequate preload), right ventricular dilation (compression of the left ventricle), systemic hypotension (decreased coronary perfusion), and hypoxemia. The pathophysiology of PAH, treatment options, and anesthetic considerations have been recently reviewed (1–3). The purpose of this study was to describe the incidence of perioperative complications and associated factors in children with PAH undergoing noncardiac surgery or cardiac catheterization.