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Learning About Paracentesis

What is paracentesis?

Paracentesis (say "pair-uh-sen-TEE-sus") is a procedure that removes fluid from the belly. The buildup of fluid may be caused by infection, inflammation, an injury, or other problems.

Swelling from too much fluid may cause pain or trouble breathing. The doctor will remove the extra fluid with a needle attached to a tube.

Why is paracentesis 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.
  • Remove a large amount of fluid that is causing pain or trouble breathing or that is affecting how the kidneys or the intestines (bowel) are working.

How is the procedure done?

You will empty your bladder before the procedure.

Your doctor or nurse will clean the area of your belly where the needle will go in. Then sterile towels will be put around the area.

You may get a shot of numbing medicine in the skin of your belly. Then your doctor will gently insert a needle where the fluid is. Your doctor may attach a tube (catheter) to the site to help collect the fluid.

After the fluid has drained, your doctor will take out the needle or catheter and put a bandage on the site.

How long does a paracentesis take?

The procedure may take from a few minutes to 30 minutes or more.

What happens after the test?

You can do your normal activities after the procedure, unless your doctor tells you not to.

After the procedure, you may have some clear fluid draining from the site, especially if a large amount of fluid was taken out. There will be less drainage in 1 to 2 days. Ask your doctor how much drainage to expect.

A small gauze pad and bandage may be needed. You may need to change the bandage.

If your doctor thinks that testing the fluid can help find out the cause of a problem, your doctor will send it to a lab.

If fluid builds up in your belly again, your doctor may repeat this procedure.

When should you call for help?

Call 911 anytime you think you may need emergency care. For example, call if:

  • You passed out (lost consciousness).

Call your doctor or nurse advice line now or seek immediate medical care if:

  • You are dizzy or light-headed, or you feel like you may faint.
  • You have new or worse belly pain.
  • You have symptoms of infection from the paracentesis site, such as:
    • Increased pain, swelling, warmth, or redness.
    • Red streaks leading from the area.
    • Pus draining from the area.
    • A fever.

Watch closely for changes in your health, and be sure to contact your doctor or nurse advice line if:

  • Fluid builds up in your belly again.
  • You do not get better as expected.

Where can you learn more?

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