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What is paracentesis?

Paracentesis [par-uh-sen-TEE-sis], also known as an abdominal [ab-DOM-uh-nl] tap, is a procedure that’s done to remove fluid from the area between the belly and the spine, an area known as the abdominal cavity.

There are two kinds of paracentesis.

  • Diagnostic. In this procedure, only a small amount of fluid is removed from the abdomen. The fluid is then used to test for any conditions that may need further treatment.
  • Large volume. In this procedure, lots of fluid may be removed to relieve pain and buildup. Several quarts of liquid may be removed at once.

In some cases, a small cut is made to guide the needle into the right place. The cut can require stitches once the procedure is done. Once the fluid is removed, it is sent to a lab to test for signs of other conditions.

Paracentesis may not cure the condition that’s causing the fluid to build up, and another procedure may be needed if the fluid builds up again.

What are the risks and/or side effects?

Some of the risks of paracentesis include:

  • Puncture. The needle used for the procedure has a very small chance to puncture the bowels, bladder, or a blood vessel.
  • Infection. There is a small chance for an infection.
  • If a lot of fluid is taken out, there is a risk for lowered blood pressure or kidney failure.

After having the procedure, you may feel:

  • Numb
  • Dizzy
  • Lightheaded

What are the benefits?

Paracentesis can help doctors figure out how much fluid is in the abdominal cavity. Normally there should only be a small amount of fluid, or none.

Sometimes a large amount of fluid can build up in the space and cause pain. Paracentesis can relieve this pain, and help figure out if there’s an infection or other condition that’s causing the buildup.

The fluid taken from a paracentesis procedure will be sent to a lab and tested for signs of other conditions, including:

  • Liver cirrhosis [sih-ROW-sis]
  • Bowel damage
  • Heart disease
  • Kidney disease
  • Pancreatic disease
  • Infection
  • Cancer that has spread to the abdominal cavity

How do I prepare?

Make sure your doctor knows if you:

  • Have allergies to latex or any numbing medicines
  • Are taking any other medications including nontraditional or herbal medicines
  • Have problems with bleeding
  • Are pregnant, or may be pregnant

Make sure to empty your bladder before the procedure starts.

How is it done or administered?

Paracentesis can be done in the doctor’s office or in the hospital and usually doesn’t take long.  Usually, the doctor doing your paracentesis will:

  • Clean the spot on your abdomen where the procedure will take place. This spot might also need to be shaved if it has hair.
  • Give you local anesthesia to numb the skin and reduce pain. You might feel a sting when the anesthesia is given.
  • Put a needle one or two inches into your abdomen. Sometimes a cut is made to help the needle get in easier. A syringe is used to draw the fluid out.
  • Once the needle is removed, the area will be bandaged. If your doctor made a cut to help insert the needle, you may need stitches to close it back up.
  • In some cases, an ultrasound will be used to make sure the needle goes into the right place. Ultrasounds don’t cause any pain.

When will I know the results?

The fluid that is taken out of your body will be sent to a lab to be tested. The time it may take for the lab to get the results back to you varies.

If you had a paracentesis to remove a larger volume of fluid from your abdominal cavity, you might notice that you have less pain right away, since the fluid isn’t pressing on your belly anymore. 

What are follow-up requirements and options?

Paracentesis can help you feel better, but it might not cure the condition that causes the fluid to build up in the abdominal cavity. Because of this, your doctor might suggest another treatment or testing to figure out how to treat the other condition. You may need a follow-up visit to the doctor to discuss the results of the procedure and plan for treatment of other conditions as they are diagnosed.
Paracentesis [par-uh-sen-TEE-sis], also known as an abdominal tap, is a procedure in which fluid is removed from the abdominal cavity to relieve abdominal pain and/or diagnose other conditions. A needle is inserted into the abdomen and fluid is taken out with a syringe. The area around the insertion site is numbed so the needle doesn’t cause pain.