Thoracentesis is the removal of excess fluid from the space between the lungs and the chest wall (pleural space).

Possible Complications

Problems are rare, but all procedures have some risk. The doctor will go over some problems that could happen, such as:

  • Infection
  • Bleeding
  • Fluid building up again
  • Collapsed lung
  • Damage to the lung, liver, or spleen

Things that may raise the risk of problems are:

Things that may raise the risk of problems are:

  • Smoking
  • Chronic lung problems, such as emphysema or asthma



This content is reviewed regularly and is updated when new and relevant evidence is made available. This information is neither intended nor implied to be a substitute for professional medical advice. Always seek the advice of your physician or other qualified health provider prior to starting any new treatment or with questions regarding a medical condition.

Edits to original content made by Denver Health.

a (Pleural Fluid Aspiration; Pleural Tap)


American Lung Association 

American Thoracic Society 


The Canadian Institutes of Health Information 

The Lung Association 


How to Do Thoracentesis. The Merck Manual Professional Edition website. Available at: Updated June 2019. Accessed May 5, 2020.

Thoracentesis. American Thoracic Society. Available at: Updated February 2016. Accessed May 5, 2020.

Thoracentesis. EBSCO DynaMed website. Available at: . Updated March 25, 2020. Accessed May 5, 2020.

Thoracentesis. Johns Hopkins Medicine website. Available at:,P07761. Accessed May 5, 2020.

Thoracentesis. National Heart Lung and Blood Institute website. Available at: Accessed May 5, 2020.