Osmosis video - Pleural effusion: Clinical

Pleural effusion refers to the accumulation of fluid in the pleural cavity. This fluid can impede the lungs' movement and make it difficult to breathe. There are various kinds of pleural effusion, depending on the nature of the fluid and what caused its entry into the pleural space. Pleural effusion can be hydrothorax (serous fluid), hemothorax (blood), urinothorax (urine), chylothorax (chyle), or pyothorax (pus).

Transudative pleural effusion contains decreased protein content and is usually due to increased hydrostatic pressure. Exudative pleural effusion contains increased protein content and is commonly due to malignancy, pneumonia, collagen vascular disease, or trauma.

Diagnosis may require thoracentesis which can help alleviate symptoms, a chest X-ray, or a CT scan. Treatment depends on the underlying cause and may involve antibiotics for infection, chemotherapy if the cause was cancer, and managing the heart or renal failure if they are the underlying causes.