How It Is Done
This procedure may be done in your doctor's office, an emergency room, or the X-ray department of a hospital, or at your bedside in the hospital.
You will empty your bladder before the procedure.
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 the skin of your belly. When the area is numb, your doctor will gently and slowly put the paracentesis needle in where the extra fluid is likely to be. 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 fluid is being removed for testing, your doctor will use a syringe to take a sample of fluid.
If there's a large amount of fluid, 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. 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.
How long the test takes
The procedure may take from a few minutes to 30 minutes or more.