Pulmonary edema of mountaineers
Overview
A severe complication of mountain sickness resulting from a lack of oxygen at high altitudes.
Symptoms
* Breathing difficulty * Restlessness * Cough * Rales * Mild fever * Mild leukocytosis * Headache * Vomiting * Tachycardia * Cyanosis * Retinal bleeding * Swelling of optic disk * Memory problems * Disorientation * Loss of consciousness
Causes
Pulmonary hypertension begins as hypertrophy of the small pulmonary arteries. The medial and intimal muscle layers of these vessels thicken, decreasing distensibility and increasing resistance. This disorder then progresses to vascular sclerosis and obliteration of small vessels. In most cases, pulmonary hypertension occurs secondary to an underlying disease process, including: *alveolar hypoventilation from chronic obstructive pulmonary disease (most common cause in the United States), sarcoidosis, diffuse interstitial disease, pulmonary metastasis, and certain diseases such as scleroderma (In these disorders, pulmonary vascular resistance occurs secondary to hypoxemia and destruction of the alveolocapillary bed. Other disorders that cause alveolar hypoventilation without lung tissue damage include obesity, kyphoscoliosis, and obstructive sleep apnea.) *vascular obstruction from pulmonary embolism, vasculitis, and disorders that cause obstruction of small or large pulmonary veins, such as left atrial myxoma, idiopathic veno-occlusive disease, fibrosing mediastinitis, and mediastinal neoplasm *primary cardiac disease, which may be congenital or acquired. Congenital defects that cause left-to-right shunting of blood — such as patent ductus arteriosus or atrial or ventricular septal defect — increase blood flow into the lungs and, consequently, raise pulmonary vascular pressure. Acquired cardiac diseases, such as rheumatic valvular disease and mitral stenosis, increase pulmonary venous pressure by restricting blood flow returning to the heart. Primary (or idiopathic) pulmonary hypertension is rare, occurring most commonly — and with no known cause — in women between ages 20 and 40. Secondary pulmonary hypertension results from existing cardiac, pulmonary, thromboembolic, or collagen vascular diseases or from the use of certain drugs.
Diagnosis
* High Blood Pressure: Home Testing * Home Blood Pressure Tests * Home Blood Pressure Monitors * Home Heart Tests * Heart Health: Home Testing: * Heart Rate Monitors * Irregular Heartbeat Detection * Heart Electrocardiogram (ECG) * Home Cholesterol Tests * Home Lung Function Tests
Treatment
Treatment usually includes oxygen therapy to decrease hypoxemia and resulting pulmonary vascular resistance. It may also include vasodilator therapy (nifedipine, diltiazem, or prostaglandin E). For patients with right-sided heart failure, treatment also includes fluid restriction, cardiac glycosides to increase cardiac output, and diuretics to decrease intravascular volume and extravascular fluid accumulation. Treatment also aims to correct the underlying cause. Some patients with pulmonary hypertension may be candidates for heart-lung transplantation to improve their chances of survival.