A procedure called thoracentesis removes fluid from the pleural space, which surrounds your lungs.

Pleura is the thin layer that lines the lungs and chest wall. As your lungs expand and contract during the process of breathing, a minute amount of fluid located between these two layers facilitates their smooth movement in relation to each other. Pleural fluid is necessary for breathing in the same way that oil is needed on a hinge to provide smooth door movement.

Breathing becomes difficult due to pleural effusion, a condition where fluid leaks into the pleural space caused by certain diseases and situations. Thoracentesis is a procedure used by doctors to treat symptoms or check the fluid for disease.

Reasons for undergoing the procedure

Thoracentesis might be necessary if you have a pleural effusion in order to investigate the source or to provide you with more comfort.

Thoracentesis is performed to assess the fluid surrounding your lungs or to treat your symptoms, or both. Among the frequent causes of thoracentesis are:

  • Infection. Your doctor may take some fluid for testing if they believe you have an infectious disease (such as a bacterial infection) that is the cause of your pleural effusion. The etiology of the infection may be determined with the aid of pleural fluid tests.
  • Cancer. Your doctor can check for cancer cells in your pleural fluid to see whether it could be the cause of your pleural effusion.
  • Reduction of symptoms. Your healthcare professional may drain part of the fluid from your pleural effusion if it is causing breathing difficulties for you.

Conditions treated by thoracentesis

Pleural effusion, or an accumulation of fluid in the pleural space between the lungs and the chest wall, is treated using thoracentesis. It assists in symptom relief and helps identify potential causes of the fluid so that your provider can treat it accordingly. Pleural effusion is caused by a variety of underlying diseases, including:

  • Lung infections, whether bacterial, fungal, or viral.
  • Autoimmune illnesses such as Systemic Lupus Erythematosus (SLE).
  • Pulmonary embolisms.
  • Pulmonary hypertension.
  • Pancreatitis, or inflammation of the pancreas.
  • Kidney or liver disease.
  • Tuberculosis (TB).
  • Congestive heart failure.
  • Cancer.

Pleural effusion is most frequently caused by heart failure.


Thoracentesis is a minimally invasive, safe technique. Thoracentesis complications are typically not life-threatening. By using imaging to locate the fluid prior to the treatment, they are reduced. To learn more about the hazards in your particular situation, ask your doctor.

The following are the risks of thoracentesis:

  • Infection. There’s always a chance that bacteria will enter your body through a skin breach and result in an infection.
  • Bleeding. If the needle punctures a blood vessel, bleeding may result. Usually small, this goes away on its own. In rare cases, bleeding may require surgery to stop.
  • Pulmonary edema. Thoracentesis may result in pulmonary edema, or an accumulation of fluid inside your lungs, if it drains the fluid surrounding your lungs too quickly.
  • Pneumothorax. Your lung could get punctured by the needle, allowing air to escape. Your lung may collapse entirely or in part as a result.

Before the procedure

You will receive detailed instructions from your doctor on how to get ready for a thoracentesis. They might request that:

  • After a specified amount of time, stop taking your medications.
  • After the procedure, have someone drive you home.

Inform your doctor if you have the following:

  • Experiencing bleeding or blood clotting conditions.
  • Consuming an aspirin or blood thinner.
  • Consuming any additional vitamins, supplements, or prescription or over-the-counter medications.
  • Have or may have a pregnancy.

Before the procedure

Your doctor will take your blood pressure and measure your blood oxygen level using a little device on your finger before to doing a thoracentesis. Prior to the procedure, imaging (X-ray, ultrasound, or Computed Tomography (CT) scan) will be used to determine the location and volume of the fluid.

You’ll take off your jewelry and change into a gown with an open back. You will be asked to sit with your arms resting on a table by your doctor. You can lie on your side if you are unable to sit.

During the procedure

A thoracentesis typically takes fifteen minutes and is performed in a hospital. Throughout the operation, your doctor may instruct you to hold your breath or not move.

While they remove the fluid, you can experience pressure or discomfort, but it shouldn’t hurt. Inform your doctor if you have dyspnea, shortness of breath, or fainting.

Your doctor perform the following during the procedure:

  • Attach you to devices that monitor your vital signs, including heart rate.
  • Administer oxygen to you via a mask or a tube (cannula) in your nose.
  • Use an antiseptic to clean a section of your back, then cover it with a drape.
  • Use local anesthetic and a needle to numb the region. When they insert the needle, you can experience a pinch. After doing this, they could wait a few minutes to be sure the area is completely numb.
  • To remove fluid, make a tiny incision in your skin and put another needle in between your ribs. They might guide the needle with the use of a portable ultrasound instrument. The fluid is drained by a tube that is fastened to the needle.
  • Take out the needle and apply a bandage to the wound. It ought to recover by itself.

After the procedure

Your doctor might take another X-ray or ultrasound of your lungs following a thoracentesis. Once you’re cleared to go, they’ll keep an eye on your vital signs if you’re heading home.

After thoracentesis, you can cough for up to an hour. This is typical and facilitates the expansion of your lungs.

The drained fluid is typically sent to a lab by your doctor. The laboratory will search for indications of infectious diseases or other pleural effusion causes. You will be informed by your doctor of their findings and any implications for your health.


After thoracentesis, recovery is brief. Your doctor could advise you to abstain from physically demanding activities for 48 hours. Usually, the bandage can be removed after a day.

Inquire with your healthcare practitioner about how to handle any discomfort, coughing, or fluid leakage from the drainage site that you may experience following the treatment. Observe their post-operative care guidelines.

As soon as you feel well enough, you ought to be able to resume your regular activities, such as going to work or school. Find out from your doctor if there are any limitations on your activities following a thoracentesis.