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Pleural Aspiration
Pleural aspiration uses a needle to remove fluid from the space around the lungs, to relieve breathlessness and to test the fluid.
Quick answer
Pleural Aspiration: what it is and what the results mean
Pleural aspiration (thoracentesis) involves passing a needle through the chest wall, often with ultrasound guidance, to draw off fluid that has collected in the pleural space between the lung and the chest wall.
- Why it is done: It is used to relieve breathlessness caused by a build-up of fluid (pleural effusion), and to test the fluid to find the cause, such as infection, heart failure, inflammation or cancer.
- Understanding results: Removing fluid can quickly ease breathing.
What it is
Pleural aspiration (thoracentesis) involves passing a needle through the chest wall, often with ultrasound guidance, to draw off fluid that has collected in the pleural space between the lung and the chest wall.
Why it is done
It is used to relieve breathlessness caused by a build-up of fluid (pleural effusion), and to test the fluid to find the cause, such as infection, heart failure, inflammation or cancer.
What to expect
You usually sit leaning forward over a table. After local anaesthetic, a needle or thin tube is passed between the ribs to remove fluid; you may feel pressure. Ultrasound is often used for safety. It takes about 15–30 minutes.
Understanding the results
Removing fluid can quickly ease breathing. The fluid is analysed for cells, protein, infection and sometimes cancer cells, helping identify the underlying cause and guide further treatment.
Good to know
Risks and limitations
Risks are small but include a collapsed lung (pneumothorax), bleeding, infection or discomfort. Ultrasound guidance reduces risks. A chest X-ray may be done afterwards to check the lung.
Education and reference only. This explains the test in general terms and is not medical advice. Always follow the specific instructions from the team arranging your test, and discuss your results with your clinician.
Answers
Pleural Aspiration: frequently asked questions
Will pleural aspiration help my breathing straight away?
Often yes. Removing fluid that is pressing on the lung can relieve breathlessness quite quickly, though how much depends on the amount of fluid and the underlying cause.
What is the main risk of the procedure?
The main risk is a small air leak causing part of the lung to collapse (pneumothorax). Ultrasound guidance lowers this risk, and a check X-ray may be done afterwards.
Related tests
Other other investigations
Sources
Where this is drawn from
- NHS — Tests and treatments
- NICE — diagnostic guidance
- Relevant royal college / professional body
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