Pulmonary embolism.

Pulmonary embolism is a common and often fatal postoperative complication. Dyspnea is the most common clinical manifestation in pulmonary embolism, and other signs are frequently inconsistent and often vague. The chest film and electrocardiogram may be helpful in excluding other cardiorespiratory diseases but they are frequently unreliable in establishing an objective diagnosis of pulmonary embolism. Documentation of a decreased arterial saturation provides suggestive evidence of pulmonary embolism. Lung scanning is a safe, sensitive procedure for the initial evaluation of symtoms suggestive of pulmonary embolism, and pulmonary arteriography may be necessary to confirm the diagnosis in certain patients. Anticoagulation is effective in the prevention and treatment of pulmonary embolism and proves successful in the vast majority of patients. Emboli that are not fatal gradually resolve in the pulmonary circulation. Vena caval interruption is occasionally beneficial in selected patients, especially those with septic emboli and cor pulmonale, but should only be performed when the indications are quite clear. Under certain selected circumstances pulmonary embolectomy may be indicated. Patients with massive embolism occluding more than one-half of the pulmonary arterial system and prooducing a markedly elevated pulmonary arterial pressure and severe hypoxemia may die in acute right heart failure. Intractable shock unresponsive to aggressive medical therapy in these patients represents an indication for pulmonary embolectomy. The hazards of these surgical procedures demand that a definite diagnosis of pulmonary embolism be made and a systematic approach to the diagnosis and treatment should be followed in all patients with the disorder.