PULMONARY HYPERTENSION AND CURRENT ANESTHETIC IMPLICATIONS

The pulmonary circulation is a high flow, low pressure system. Pulmonary hypertension (PH) exists when the mean pulmonary artery pressure (PAP) is 25mm Hg at rest, or 30mm Hg during exercise. PH has been described as being either primary or secondary. It is termed primary in the absence of secondary causes, such as pulmonary disease (e.g., COPD, ARDS), cardiac disease (e.g., shunts, left ventricular failure), thromboembolic disease, or other pathologic processes. Primary pulmonary hypertension PPH is a rare disease (1 to 2 per million), occurs three times more frequently in women than in men, and has a poor prognosis. Patients with PPH typically have a mean PAP 60mm Hg. Secondary pulmonary hypertension is more common but elevations in PAP are generally less severe (rarely 40mm Hg). The signs and symptoms of PH are nonspecific and subtle. Left untreated, patients will experience progressive symptoms of dyspnea and right heart failure culminating in markedly curtailed survival.