Paracentesis

This page has been prepared to help you understand more about drainage of abdominal fluid (paracentesis). If you are unsure or concerned about anything, please ask hospice staff.

What is paracentesis?

Paracentesis is a procedure in which a small tube is inserted through your abdominal wall to remove fluid from within your abdomen. Inside the abdomen is a membrane called the peritoneum. The peritoneum covers the organs inside your abdomen and produces a fluid which lubricates these organs and helps them to glide smoothly over one another. Sometimes too much of this fluid can be produced causing discomfort, this is known as ascites.

Ascites can be a symptom of many types of cancer. The types of cancer that are more likely to cause ascites are breast cancer, lung, large bowel (colon), stomach, pancreas, ovary, and the lining of the womb (endometrium).

What causes the build up of fluid?

There are a number of possible causes:

  • If cancer cells have spread to the lining of the abdomen they can cause irritation, leading to the build up of fluid
  • If the liver is affected by cancer it can cause a blockage in the blood circulating through it, leading to a build up of fluid in the abdomen. Alternatively liver damage can change the body’s fluid balance, causing fluids to build up in the body’s tissues, including the abdomen
  • Cancer can also affect the lymphatic system. The lymphatic system is a network of fine channels running throughout the tissues of the body. One of its functions is to drain off excess fluid and return it to the blood stream. If some of these channels are blocked, the system cannot drain efficiently and fluid can build up

What are the symptoms of ascites?

  • Swelling of the abdomen, with associated pain or discomfort
  • Difficulty in moving or sitting comfortably
  • Breathlessness
  • Tiredness
  • Nausea and vomiting
  • Indigestion
  • Reduced appetite
  • Altered bowel habit

A paracentesis will only be done if it will benefit you and improve your comfort.

How is a paracentesis done?

You will be asked to lie on an examination bed or couch. An injection to numb the skin is given, and a small tube inserted into the abdomen; this is secured by tape. The fluid (ascites) will drain through this tube into a drainage bag. You will be able to move around whilst the fluid is being drained.

When all the fluid has drained, the tube is removed and a dressing is applied over the drainage site. In out-patients clinic the procedure takes 5 to 6 hours and you can go home the same day. The procedure can also be done as an in-patient, for example if it is your first paracentesis or there is a lot of fluid to be drained. The drain can then be left in for 24 hours or longer.

Sometimes fluid can build up again, if this happens then you may need another paracentesis.

In some cases, an ultrasound scan is done to identify the best place to insert the tube.

What are the risks associated with paracentesis?


If a large quantity of fluid is removed, there is a small risk of lowered blood pressure. Your blood pressure will be checked during the procedure.

The tube draining the fluid can become blocked. This can sometimes be resolved by changing your position or sitting upright. If this does not work then the tube might have to be manipulated or replaced.

The site of the drain can become infected despite all measures taken to prevent this. The site will be observed regularly and your temperature will be checked. If this does occur then it can be treated with antibiotics.

There is a slight chance that your bowel may be punctured during the procedure. This may cause bleeding or infection and in extreme circumstances could require an operation. We will check that you are not at risk of bleeding by doing a blood tests before you are due to have paracentesis.

In some cases, the fluid will continue to leak from the drainage site after the drain has been removed. A drainage bag is adhered over the site until the leaking stops, normally 12/24 hours after the drain is removed.

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