What is thoracentesis?

Thoracentesis (say "thor-uh-sen-TEE-sis") is a procedure to remove fluid from the space between the lungs and the chest wall. This is called the pleural space. The procedure may also be called a "chest tap."

It is normal to have a small amount of fluid in the pleural space. Too much fluid can build up because of problems such as infection, heart failure, and lung cancer. The procedure may be done to help with shortness of breath and pain caused by the fluid buildup, or you may have it done so the doctor can test the fluid to find the cause of the buildup.

Your doctor will put a long, thin needle or a thin plastic tube, called a catheter, between two of your ribs. The doctor will use the needle or catheter to take fluid out.

You may get medicine before the procedure. This helps with pain and helps you relax. The procedure will take about 15 minutes. You can go back to work or your normal activities as soon as you feel up to it.

How do you prepare for the procedure?

Preparing for the procedure

• Be sure you have someone to take you home. Anesthesia and pain medicine will make it unsafe for you to drive or get home on your own.
• 
  Understand exactly what procedure is planned, along with the risks, benefits, and other options.
• Tell your doctor ALL the medicines and natural health products you take. Some may increase the risk of problems during your procedure. Your doctor will tell you if you should stop taking any of them before the procedure and how soon to do it.
• If you take a medicine that prevents blood clots, your doctor may tell you to stop taking it before your procedure. Or your doctor may tell you to keep taking it. (These medicines include aspirin and other blood thinners.) Make sure that you understand exactly what your doctor wants you to do.
• Make sure your doctor and the hospital have a copy of your advance care plan. If you don't have one, you may want to prepare one. It lets others know your health care wishes. It's a good thing to have before any type of surgery or procedure.

What happens on the day of the procedure?

• Take off all jewellery and piercings.

At the hospital, surgery centre, or doctor's office

• 
  Bring a picture ID.
• The doctor may take a chest X-ray or use ultrasound or CT scan pictures to help find the exact spot where fluid has built up.
• The doctor will give you a shot of numbing medicine in the skin where the needle or catheter will go.
• The procedure will take about 15 minutes.
• The doctor may take a chest X-ray after the procedure.
• You will probably be able to go home or to a hospital room after the procedure.