Pleural effusion

Some people with pleural effusion do not experience any symptoms and may only become aware they have the condition when it’s detected during testing for another health issue.

If you do experience symptoms of pleural effusion, they may include:

• Shortness of breath
• Chest pain
• A persistent cough
• Fatigue
• Orthopnea (difficulty breathing unless sitting or standing upright)

To diagnose pleural effusion, our specialist team will first evaluate your symptoms and perform a physical examination to check your breathing.

Next, we may advise imaging scans to thoroughly assess your lungs and check for fluid build-up.

Imaging tests to confirm pleural effusion can include:

• Chest X-ray – this is used to confirm the presence of fluid around your lungs
• Ultrasound – provides a detailed view of your lungs and can also guide the needle during a procedure called thoracentesis (which is used to drain extra fluid from around the lungs)
• Computed tomography (CT) scan – this helps identify the underlying cause of pleural effusion, such as infections or other abnormalities

Another type of test to confirm or rule out pleural effusion is thoracentesis. This is where a needle is carefully inserted between your ribs and into your lungs to sample the fluid from the pleural space.

We then analyse the fluid for high levels of protein and other markers that may suggest pleural effusion and determine the type.

There are many potential causes of pleural effusion, with some people having more than one underlying factor. Once we determine which type of pleural effusion you have, we can usually identify the specific cause.

The most common causes of pleural effusion include:

• Heart failure – this is the most common cause of transudative pleural effusion, typically due to increased pressure in the blood vessels
• Infection – conditions like pneumonia can lead to exudative pleural effusion due to the inflammation they cause
• Cancer – if cancer cells spread between the pleural layers in your lungs, it can prompt your body to produce excessive fluid, leading to pleural effusion
• Pulmonary embolism – a blood clot that blocks blood flow to the pulmonary arteries, potentially leading to fluid build-up around the lungs
• Kidney or liver disease – these conditions can cause fluid to accumulate in the abdomen, which may then leak into the pleural space around the lungs
• Autoimmune disorders – inflammation caused by these disorders can affect the pleura, increasing the risk of fluid leaking into the pleural space
• Open-heart surgery – inflammation and diaphragm dysfunction caused by surgery can increase the risk of pleural effusion