Cardiovascular and Interventional Radiological Society of Europe

Pleural effusion


Pleural effusion is the collection of excessive amounts of fluid in the envelope-like space that surrounds the lungs (called the pleural cavity). The characteristics and thickness of the effusion depend on the origin of the fluid and the cause of the build-up and must be investigated.


In many cases, when the pleural effusion is small, there are no obvious symptoms. However, if there is a large amount of fluid or there is an inflammation, you may notice symptoms such as shortness of breath (called dyspnoea), chest pain, cough and fever.


To diagnose you, a doctor will first physically examine you with a stethoscope, or use a technique called percussion (tapping body parts with fingers, hands or small instruments). Then the diagnosis can be confirmed by taking a chest X-ray. Other imaging techniques such as CT (or CAT) scan, and chest ultrasound can be used to provide further information. A great number of conditions can determine a pleural effusion, both benign (infection, inflammation, heart failure, kidney failure) and malignant (cancer), and can be diagnosed through laboratory blood tests, imaging techniques, and pleural fluid analysis.


The exact treatment will depend on the cause of the effusion, and on whether or not you are experiencing any symptoms. If there is a large amount of pleural fluid, the doctor may remove some of the fluid by inserting a needle through the chest wall between the ribs, and attaching it to a syringe, in a procedure called aspiration. This is done both to investigate the cause of the effusion (analysing the fluid) and to relieve the symptoms. If the effusion is large or infected, the doctor may insert a thin drainage tube into the pleural space to drain the fluid, using image guidance to properly place the tube. This should relieve your symptoms and prevent complications.

If you regularly suffer from effusions, it may be necessary to undergo a procedure called pleurodesis, which can either be carried out by injecting chemicals in the pleural space or through surgery. If pleurodesis fails, you may need a treatment called pleural decortication, which involves surgically removing the problematic layer of fibrous tissue.