The pleura are two thin, moist membranes around the lungs. They let your lungs expand and contract. The inner layer is attached to the lungs. The outer layer is attached to the ribs. Pleural effusion is a buildup of extra fluid in the space between the pleura. This can make it hard for the lungs to open all the way. This can make it hard to breathe.

Pleural Effusion
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The cause is usually disease or injury. Pleural effusion may be watery (transudative) or thick (exudative).

The transudative type may be from:

The exudative type may be from:

Risk Factors

Factors that may raise your risk are:

  • Having the health problems above
  • Taking certain medicines
  • Chest injury
  • Radiation therapy
  • Surgery, especially involving:
    • Heart
    • Lungs
    • Abdomen
    • Organ transplants


Some types of pleural effusion do not cause symptoms. Others may cause:

  • Shortness of breath
  • Shallow breathing
  • Rapid heartbeat or breathing
  • Chest pain
  • Stomach pain
  • Cough
  • Coughing up blood
  • Weight loss
  • Fever or chills
  • Hiccupping


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

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

Pictures may be taken to view your lungs. This can be done with:

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


Treatment depends on what is causing the problem. It may include medicines or surgery.

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

Help Breathing

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

Drain the Pleural Effusion

The pleural effusion may be drained by:

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

Seal the Pleural Layers

The doctor may advise chemical pleurodesis. Talc powder or an irritating chemical is injected into the pleural space. This will seal the two layers of the pleura together. This may help prevent further fluid buildup.

Radiation therapy may also be used to seal the pleura.


In severe cases, surgery may be done. Some of the pleura will be removed during surgery. Options are:

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


Manage health problems that may lead to effusion.


American Lung Association

National Heart, Lung, and Blood Institute


Health Canada

The Lung Association


Pleural effusion. EBSCO DynaMed Plus website. Available at: Updated April 30, 2018. Accessed August 28, 2018.

Pleural effusion. Merck Manual Professional Version website. Available at: Updated October 2017. Accessed August 28, 2018.

Pleural effusion. Remedy's Health Communities website. Available at: Updated October 1, 2015. Accessed August 28, 2018.

12/10/2010 DynaMed Plus 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.

Last reviewed May 2018 by EBSCO Medical Review Board Daniel A. Ostrovsky, MD  Last Updated: 8/28/2018