pleural effusion, an abnormal accumulation of fluid in the intrapleural spaces of the lungs. It is characterized by chest pain, dyspnea, adventitious lung sounds, and nonproductive cough. The fluid is an exudate or a transudate from inflamed pleural surfaces and may be aspirated or surgically drained. An exudate may result from pulmonary infarction, trauma, tumor, or infection, such as tuberculosis. The specific cause of the exudate is treated. Treatment of the effusion may include the administration of corticosteroids, diuretics, or vasodilators; oxygen therapy; intermittent positive-pressure breathing; or thoracentesis or use of a mobile system such as the Pleurx catheter.
