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    Thoracentesis

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    What is a Thoracentesis?

    Thoracentesis is a procedure performed by a doctor or nurse practitioner (NP) to remove fluid from around the lung. Thoracentesis is a quick, nearly painless procedure. Sometimes a specially trained doctor, called an Interventional Radiologist (IR), performs this procedure in the Department of Radiology. Also, an intensive care doctor or nurse practitioner (NP) might perform this procedure at the bedside of patients in the Intensive Care Unit (ICU).

    Thoracentesis is done to:

    • Relieve shortness of breath from fluid build-up around the lung.


    • Check the fluid for infection.


    • Check the fluid for disease (such as cancer).
    Moderate to large amounts of fluid around the lung can compress the lung. This decreases the lung’s ability to function and expand. In this case, patients may experience difficulty breathing when they are physically active. Sometimes patients feel short of breath while lying down. Removing the fluid from around the outside of the lung allows the lung to re-expand and function better.

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    What Can I Expect at California Pacific Medical Center?

    • If You are Coming From Home:
      Parking is available at 2405 Clay Street (corner of Clay and Webster Streets) for a fee. There is no validation for parking.


    • If You are in the Hospital, the Staff Explains the Procedure:
      A thoracentesis is done in your hospital room.


    • Signing the Consent Form:
      The doctor explains the procedure. Then he/she asks you to sign a consent form stating that you understand the thoracentesis procedure. This is a good time for you to ask questions and to share any concerns.

    During the Procedure

    • The staff positions you comfortably for this procedure. The staff may ask you to lie on your side, your back, or sit on the side of the bed, depending on the location of the fluid to be removed.


    • First, the doctor may use ultrasound as a guide during a thoracentesis. Ultrasound uses sound waves to create pictures of the internal structures of the body. The doctor uses these pictures to guide the needle placement for the test and to check for fluid around the lung.

      Note: Ultrasound may not be necessary if there is a lot of fluid around the lung.


    • Next, the doctor injects a small amount of local anesthetic under the skin to numb the area. You may feel a slight sting when the medication is injected.


    • Then, the doctor places a small, thin needle into your chest to remove the fluid.


    • As the lung re-expands toward the end of the procedure, you may experience mild tightness in the chest, or coughing. These symptoms occur especially if a large amount of fluid has been removed.


    • You will have a chest x-ray after the thoracentesis. The x-ray shows that the fluid has been removed and that the lung has re-expanded. Also, the x-ray shows any possible lung collapse (pneumothorax) which may have occurred as a result of the procedure.


    • If you are a patient in the hospital, you will return to your room after the procedure.

    Call your doctor/nurse immediately if you experience any of the following:

    • Sudden or increasing shortness of breath


    • Fever greater than 101°F


    • Excessive drainage or bleeding from the thoracentesis puncture site


    • Increasing pain in your chest when you try to take a breath

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    More Ways to Learn

    Visit the Society of Interventional RadiologyOpens new window Web site.



    Frequently Asked Questions

    Question: What is a thoracentesis?
    Answer: A thoracentesis is a procedure performed to remove fluid from around the lung.

    Question: Is this procedure painful?
    Answer: A thoracentesis is a quick, nearly painless procedure.

    Question: What happens after this procedure?
    Answer: You will have a chest x-ray after the thoracentesis. This x-ray shows that the fluid is removed and that the lung is expanded. Also, the x-ray shows any possible lung collapse (pneumothorax) which may have occurred as a result of this procedure.


    Produced by the Center for Patient and Community Education in association with the staff and physicians at California Pacific Medical Center. Date: 3/04.


    Funded by: A generous donation from the Mr. and Mrs. Arthur A. Ciocca Foundation.

    Note: This information is not meant to replace any information or personal medical advice which you get directly from your doctor(s). If you have any questions about this information, such as the risks or benefits of the treatment listed, please ask your doctor(s).

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