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Brain & Nervous System Health Center

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How It Is Done continued...

If a large amount of fluid is going to be taken out during the procedure, you may lie on your back with your head raised. People who have less fluid taken out may sit up. The site where your doctor will put the needle is cleaned with a special soap and draped with sterile towels.

Your doctor puts a numbing medicine into your belly. Once the area is numb, your doctor will gently and slowly put the paracentesis needle in where the extra fluid is likely to be. Your doctor will be careful to not poke any blood vessels or the intestines. If your test is done in the X-ray department, an ultrasound may be used to show where the fluid is in your belly.

If a large amount of fluid is present, the paracentesis needle may be hooked by a small tube to a vacuum bottle for the fluid to drain into it.

Generally, up to 4 L (1 gal) of fluid is taken out. If your doctor needs to remove a larger amount of fluid, you may be given fluids through an intravenous line (IV) in a vein in your arm. This fluid is needed to prevent low blood pressure or shock. It is important that you lie completely still during the procedure, unless you are asked to change positions to help drain the fluid.

When the fluid has drained, the needle is taken out and a bandage is placed over the site. After the test, your pulse, blood pressure, and temperature are watched for about an hour. You may be weighed and the distance around your belly may be measured before and after the test.

Paracentesis takes about 20 to 30 minutes. It will take longer if a large amount of fluid is taken out. You can do your normal activities after the test unless your doctor tells you not to.

How It Feels

You may feel a brief, sharp sting when the numbing medicine is given. When the paracentesis needle is put into your belly, you may feel a temporary sharp pain or pressure.

WebMD Medical Reference from Healthwise

Last Updated: November 14, 2014
This information is not intended to replace the advice of a doctor. Healthwise disclaims any liability for the decisions you make based on this information.

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