Pleural effusion is an abnormal accumulation of fluid in the space between the two surfaces of the lung known as pleura. It is a membrane that lines the surface of the lungs and the inside of the chest wall. Usually, this space between the pleura is empty and it allows the smooth movement of the lung expansion within the chest. In a pleural effusion, fluid accumulates in the space.
Small pleural effusions often cause no symptoms. However, the symptoms of moderate sized pleural effusions include:
Chest X-ray is useful to confirm a pleural effusion when it is suspected during physical examination. Sometimes, computed tomography (CT) of the chest may be required to confirm the presence pleural effusion and to look for any serious cause like cancer, pulmonary embolism or complicated lung infection.
Pleural Fluid Analysis: After a pleural effusion is identified on imaging, a fluid sample is usually taken to determine its characteristics especially it is suspected to be caused by pneumonia, cancer or trauma. In a procedure called thoracentesis or pleural tap, the doctor inserts a needle and a catheter between the ribs, into the pleural space. A small amount of fluid is withdrawn for testing while a large amount can be removed at the same setting to relieve symptoms. It is a simple procedure that is done in the clinic or bedside setting. Usually, the procedure is performed under ultrasound guidance to minimize complication like air leak, bleeding or injury to the internal organ.
Treatment for pleural effusion start with identifying the cause and treating the underlying condition. Examples include giving intravenous antibiotics for pneumonia, dialysis for end stage renal failure or giving diuretics for heart failure.
Inserting a pleural drain/chest tube: For pleural effusion that is large and compromised the respiration status of a patient or that repeatedly re-accumulate after a tap, a chest tube can be inserted through the skin into the pleural space. This is left for a few days to weeks to drain the effusion completely and it is performed safely under ultrasound guidance.