Paracentesis

Ascites is fluid that builds up inside the belly, in the space around the bowel and other organs, called the peritoneal cavity. A small amount causes no symptoms. Several liters can make the belly tight and swollen.

On ultrasound, ascites looks black, and loops of bowel float in it like gray shapes. We choose a deep pocket of fluid, usually in the lower side of the belly, away from the bowel and the blood vessels in the belly wall.

About 8 in 10 cases of ascites in the United States are caused by cirrhosis, which is advanced scarring of the liver. Scarring raises the pressure in the veins of the liver (portal hypertension) and lowers the body's protein levels, so fluid leaks into the belly. Cancer is the next most common cause, often from the ovary, pancreas, colon, stomach or breast. Heart failure, kidney disease, infection such as tuberculosis and inflammation of the pancreas are less common causes.

The first sample of fluid is tested in the lab. The difference between protein in the blood and in the fluid shows whether portal hypertension is the cause. Cell counts check for infection, and cytology looks for cancer cells.

In people with cirrhosis, mildly abnormal clotting tests or low platelets usually do not stop a paracentesis. Serious bleeding is rare even then. Your team will check your numbers and decide.

1. 1
   Positioning

   You lie on your back on the table with your head slightly raised, sometimes tilted a little to one side.

2. 2
   Ultrasound and numbing

   We find the best pocket of fluid with ultrasound, mark it, clean the skin and numb it down to the lining of the belly.

3. 3
   Draining the fluid

   A thin needle with a soft plastic tube over it goes into the fluid. The needle comes out, leaving only the soft tube, and fluid drains into vacuum bottles. You may feel pressure, but it is usually not painful.

4. 4
   Finishing up

   We remove the tube and cover the spot with skin glue or a bandage. If needed, albumin is given through an IV.

If you have cirrhosis and we remove more than about 5 liters, we usually give albumin, a protein made from donated blood, through an IV. It helps keep fluid in your blood vessels and protects your kidneys and blood pressure.

Many of my paracentesis patients come back every week or two, and I get to know them well. I scan every time, because the fluid and the bowel shift, and I pick a fresh spot away from old punctures. If you are coming in very often, I will talk with your liver or cancer doctor about whether TIPS or a home drain could give you more time between visits.

Fabio Komlos, MD, interventional radiologist · About Dr. Fabio Komlos

1. Right after
   Rest for a short time while we check your blood pressure. Most people feel lighter and can breathe and eat more easily right away.
2. Same day
   Go home and resume your usual activities. You can shower the same day and eat normally.
3. Next 1–2 days
   Mild soreness at the site is normal. A little clear fluid may leak; a folded gauze pad helps.
4. Ongoing
   Follow your low-salt diet and water pill plan. Your doctor will review the lab results with you.

Use acetaminophen (Tylenol) for soreness. If you have cirrhosis, keep to no more than 2,000 mg a day unless your doctor says otherwise, and avoid ibuprofen and naproxen, which can harm the kidneys.

With ultrasound guidance, paracentesis is very safe. Serious bleeding and infection each happen in fewer than 1 in 100 procedures. Injury to the bowel is very rare. Fluid leaking from the puncture site for a day or two is the most common problem and usually stops on its own. Some people feel dizzy or have low blood pressure after a large drainage, which albumin helps prevent.