Paracentesis

Paracentesis is a procedure to take out fluid that has collected in the belly (peritoneal fluid). This fluid buildup is called ascites. Ascites may be caused by infection, inflammation, an injury, or other conditions, such as cirrhosis or cancer. The fluid is taken out using a long, thin needle put through the belly. The fluid is sent to a lab and studied to find the cause of the fluid buildup. Paracentesis also may be done to take the fluid out to relieve belly pressure or pain in people with cancer or cirrhosis.

Why it is Done

Paracentesis may be done to:

  • Find the cause of fluid buildup in the belly.
  • Diagnose an infection in the peritoneal fluid.
  • Check for certain types of cancer, such as liver cancer.
  • Remove a large amount of fluid that is causing pain or difficulty breathing or that is affecting how the kidneys or the intestines (bowel) are working.
  • Check for damage after a belly injury.