Health Library

Pleural Effusion


The pleura are 2 thin, moist membranes around the lungs that allow your lungs to expand and contract easily. The inner layer is attached to the lungs. The outer layer is attached to the ribs. Pleural effusion is the buildup of excess fluid in the space between the pleura. The fluid can prevent the lungs from fully opening. This can make it difficult to catch your breath.

Pleural effusion may be watery (transudative) or thick (exudative) based on the cause. Treatment of pleural effusion depends on the condition causing the effusion.

Pleural Effusion
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Effusion is usually caused by disease or injury.

Transudative effusion may be caused by:

Exudative effusion may be caused by:

Risk Factors

Factors that may increase your chance of pleural effusion include:

  • Having conditions or diseases listed above
  • Taking certain medications
  • Chest injury or trauma
  • Radiation therapy
  • Surgery, especially involving:
    • Heart
    • Lungs
    • Abdomen
    • Organ transplantation


Some types of pleural effusion do not cause symptoms. Others cause a variety of symptoms, including:

  • Shortness of breath
  • Shallow breathing
  • Rapid pulse or breathing rate
  • Chest pain
  • Stomach discomfort
  • Cough
  • Coughing up blood
  • Weight loss
  • Fever, chills, or sweating
  • Hiccupping


You will be asked about your symptoms and medical history. A physical exam will be done. This may include listening to or tapping on your chest. Lung function tests will test your ability to move air in and out of your lungs.

Some blood tests will be done based on what the doctor thinks it causing the fluid.

Images of your lungs may be taken with:

Your doctor may take samples of the fluid or pleura tissue for testing. This may be done with:


Treatment is usually aimed at treating the underlying cause. This may include medications or surgery.

If your symptoms are minor, your doctor may choose to monitor you until the effusion is gone.

To Support Breathing

If you are having trouble breathing, your doctor may recommend:

  • Breathing treatments—inhaling medication directly to lungs
  • Oxygen therapy

Drain the Pleural Effusion

The pleural effusion may be drained by:

  • Therapeutic thoracentesis—a needle is inserted into the area to withdraw excess fluid.
  • Tube thoracostomy—a tube is placed in the side of your chest to allow fluid to drain. It will be left in place for several days.

Seal the Pleural Layers

The doctor may advise chemical pleurodesis. During this procedure, talc powder or an irritating chemical is injected into the pleural space. This will permanently seal the 2 layers of the pleura together. The seal may help prevent further fluid buildup.

Radiation therapy may also be used to seal the pleura.


In severe cases, surgery may be needed. Some of the pleura will be removed during surgery. Suregery options may include:

  • Thoracotomy—traditional, open chest procedure
  • Video-assisted thorascopic surgery (VATS)—minimally-invasive surgery that only requires small keyhole size incisions


Prompt treatment for any condition that may lead to effusion is the best way to prevent pleural effusion.


American Lung Association

National Heart, Lung, and Blood Institute

Canadian Resources

Health Canada

The Lung Association


Pleural effusion. EBSCO DynaMed Plus website. Available at: Updated September 13, 2016. Accessed September 14, 2016.

Pleural effusion. Merck Manual Professional Version website. Available at: Updated September 2014. Accessed May 11, 2016.

Pleural effusion. Remedy's Health Communities website. Available at: Updated October 1, 2015. Accessed May 11, 2016.

12/10/2010 DynaMed's Systematic Literature Surveillance Roberts M, Neville E, Berrisford R, Atunes G, Ali N, et al. Management of a malignant pleural effusion: British Thoracic Society pleural disease guideline 2010. Thorax. 2010;65 Suppl 2:ii32.