What is a thoracentesis?

Thoracentesis is a procedure where a needle is put into the space between your rib cage and one of your lungs, called the pleural space, to drain fluid. The pleural space normally contains a small amount of fluid. Thoracentesis may be needed to test the fluid for infection or cancer cells. It may also be needed when excess fluid is putting pressure on the lung and making it hard to breathe. This excess fluid is called a pleural effusion.

How is thoracentesis done?

Before the procedure:

  • Your healthcare provider will ask you to sign a consent form for the thoracentesis. The consent form will state the reason you are having the procedure, what happens during the procedure, and what you may expect afterward.
  • Tell your healthcare provider if you are allergic to any medicines.
  • Tell your healthcare provider if you are taking any medicines, including nonprescription drugs, herbal remedies, or illegal drugs.
  • You will have a small tube (IV catheter) inserted into a vein in your hand or arm. This will allow medicine to be given directly into your blood and to give you fluids, if needed.

During the procedure:

  • You may be given a sedative, which will help you to relax. This is usually given in your vein (IV).
  • You will be given medicines to prevent pain during your procedure. These may include local anesthesia, which numbs the area where the thoracentesis will be done.
  • You may have a chest X-ray or CT scan so your provider can see exactly where the fluid is.
  • Your provider will put the needle into your chest and between the ribs to drain the fluid.
  • If you will need additional fluid drained later, your provider may leave a small tube in the area.
  • Your provider will put a dressing over the area.

After the procedure:

  • You will be checked often by nursing staff.
  • The dressing will be checked and changed by your provider or the nursing staff as needed.
  • Your provider may prescribe medicine to:
    • Treat pain
    • Treat or prevent an infection
    • Reduce fluid build-up and swelling in the body
    • Help relax your airways
    • Reduce swelling in the airways
  • Your blood oxygen level will be monitored by a sensor that is attached to your finger or earlobe.
  • A cardiac (heart) monitor may be used to keep track of your heart’s rate and rhythm.

What can I do to help?

  • You will need to tell your healthcare team if you have new or worsening:
    • Anxiety
    • Back pain
    • Chest pain
    • Chills or sweats
    • Cough
    • Irregular heartbeat
    • Trouble breathing
  • Ask questions about any medicine, treatment, or information that you do not understand.

How long will I be in the hospital?

How long you stay in the hospital depends on many factors. The average amount of time to stay in the hospital after a thoracentesis is 6 to 11 days.

Developed by RelayHealth.
Acute Care Advisor 2015.1 published by RelayHealth.
Last modified: 2014-04-30
Last reviewed: 2014-04-24
This content is reviewed periodically and is subject to change as new health information becomes available. The information is intended to inform and educate and is not a replacement for medical evaluation, advice, diagnosis or treatment by a healthcare professional.
Copyright ©1986-2015 McKesson Corporation and/or one of its subsidiaries. All rights reserved.

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