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Thoracentesis

By

Rebecca Dezube

, MD, MHS, Johns Hopkins University

Reviewed/Revised Nov 2023
VIEW PROFESSIONAL VERSION

Thoracentesis is the placement of a needle through the skin into the chest cavity to withdraw a sample of fluid.

In thoracentesis, fluid that has collected abnormally in the pleural space (termed a pleural effusion Pleural Effusion Pleural Effusion ) is removed. The two principal reasons to do thoracentesis are to

  • Obtain a fluid sample for diagnostic testing

  • Relieve shortness of breath caused by fluid compressing lung tissue

During the procedure, the person sits comfortably and leans forward, resting the arms on supports. A small area of skin on the back is cleaned and numbed with a local anesthetic. Then a doctor inserts a needle between 2 ribs and into the chest cavity, but not into the lung, and withdraws some fluid into a syringe. Often the doctor uses ultrasonography Ultrasonography of the Chest Chest imaging studies include X-rays Computed tomography (CT) CT angiography Magnetic resonance imaging (MRI) read more for guidance (to determine where to insert the needle). The collected fluid is analyzed to assess its chemical makeup and to determine whether bacteria or cancerous cells are present.

If a large volume of fluid has accumulated, it may need to be removed through a plastic catheter and it may be necessary to use a fluid container that is larger than a syringe. The fluid may need to be drained over several days, in which case a larger tube (chest tube Chest Tube Insertion Chest tube insertion (also called tube thoracostomy) is a procedure in which a tube is inserted into the space between the lung and chest wall (called the pleural space). The procedure is done... read more or drainage catheter) is left in the chest and suctioned continuously.

The risk of complications during and after thoracentesis is low. A person may feel some pain as the lung fills with air and expands against the chest wall or may feel the need to cough. Also, a person may briefly feel light-headed and short of breath. Other possible complications (listed roughly in order of frequency) include

A chest x-ray Chest Imaging Chest imaging studies include X-rays Computed tomography (CT) CT angiography Magnetic resonance imaging (MRI) read more may be done after the procedure to determine how much fluid may remain and whether complications have occurred.

NOTE: This is the Consumer Version. DOCTORS: VIEW PROFESSIONAL VERSION
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