Pleural Effusion

accumulation of watery fluid in the pleural cavity, between the membrane lining the thoracic cage and the membrane covering the lung. There are many causes of pleural effusion, including pneumonia, tuberculosis, and the spread of a malignant tumour from a distant site to the pleural surface. Pleural effusion often develops as a result of chronic heart failure because the heart cannot pump fluid away from the lungs, and fluid that seeps from the lungs places additional stress on the dysfunctioning heart. Large pleural effusions can cause disabling shortness of breath.

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