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by Dameron A

(Pleural Fluid Aspiration; Pleural Tap)



A pleural effusion is a build-up of fluid in the space between the lungs and the chest wall. This space is called the pleural space. Thoracentesis is a procedure to remove fluid from this area.
There are two types of thoracentesis:
  • Therapeutic thoracentesis—to relieve the symptoms of fluid accumulation
  • Diagnostic thoracentesis—to test for the cause of the fluid build-up

What to Expect


A local anesthetic will be used. It will numb the area where the needle will be inserted.

Description of the Procedure

You may be asked to sit upright on the edge of a bed or chair. Your arms will be resting on a nearby table. If your procedure involves a CT scan, you may be asked to lie on a table. Try to avoid coughing, breathing deeply, or moving during the procedure.
A small patch of skin on your back, chest, or under your armpit will be sterilized. Anesthesia will be applied to this patch. It will help numb the area.
The doctor may use ultrasound or CT scan images to guide the needle and monitor the fluid. A needle or thin plastic catheter will be inserted between your ribs. The needle or catheter is then passed into the pleural space. Some or all of the fluid will be drawn into the syringe.
Placement of Thoracentesis Needle
Placement of Thoracentesis Needle
© 2011 Nucleus Medical Media, Inc.

How Long Will It Take?

About 15 minutes

Will It Hurt?

You may feel slight pain or a stinging when the needle is first inserted. As the fluid is being extracted, you may feel a sense of pulling. Tell your doctor or nurse if you feel extreme pain, any shortness of breath, or faint.

Post-procedure Care

At the Care Center
If the thoracentesis is being done for diagnostic reasons, the fluid will be sent to a lab for testing. Often, another chest x-ray will be done to ensure that the fluid has been removed and that there is no sign of a collapsed lung.
The doctor may begin treatment for the cause of the fluid build-up.
At Home
Keep the area of skin where the needle was inserted clean and dry. To help make your recovery smooth, be sure to follow your doctor's instructions .
If a diagnostic thoracentesis was done, ask your doctor when to expect the results.


American Lung Association

American Thoracic Society



The Canadian Institutes of Health Information

The Canadian Lung Association



Harrison’s Principles of Internal Medicine . 16th ed. McGraw-Hill; 2005.

Mason RJ. Murray & Nadel's Textbook of Respiratory Medicine . 4th ed. WB Saunders; 2005.

Roberts JR. Clinical Procedures in Emergency Medicine . 4th ed. WB Saunders; 2004.

What is thoracentesis? National Heart, Lung, and Blood Institute website. Available at: . Updated February 24, 2012. Accessed April 10, 2013.

6/3/2011 DynaMed's Systematic Literature Surveillance DynaMed's Systematic Literature Surveillance : Mills E, Eyawo O, Lockhart I, Kelly S, Wu P, Ebbert JO. Smoking cessation reduces postoperative complications: a systematic review and meta-analysis. Am J Med. 2011;124(2):144-154.e8.


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