Paracentesis

What happens if a change or abnormality is found

A paracentesis is a procedure in which a hollow needle or tube is inserted through the skin and into the abdominal cavity or peritoneum. The peritoneum is the membrane that lines the walls of the abdomen and pelvis (parietal peritoneum), and covers most of the abdominal organs (visceral peritoneum). A paracentesis may also be called an abdominal tap.

Why a paracentesis is done

A paracentesis is done to:

collect fluid for examination under a microscope
remove excess fluid from the abdominal cavity or peritoneum (ascites)
- The fluid may be examined to help find the cause of the ascites.
- Removing extra fluid helps relieve abdominal swelling.

How a paracentesis is done

A paracentesis can often be done in a hospital or outpatient clinic.
The person often lays down on a bed with the head of the bed elevated for the procedure.
A local anesthetic is used to numb the area where the paracentesis needle will be inserted.
The doctor then inserts a thin, hollow needle or plastic tube (catheter) into the abdominal cavity. Once the needle is inserted, excess fluid is removed.
Sometimes an ultrasound is done to help the doctor find the right place to insert the needle or tube for a paracentesis.
A small amount of fluid is sent to the laboratory so that it can be examined under a microscope. More fluid is removed if ascites is present.
A paracentesis usually takes 20–30 minutes. It may take a little longer if there is a lot of fluid in the abdomen.
The needle or tube is removed once the fluid is drained.
A small bandage is placed on the site where the needle or tube was inserted.

Potential side effects

The risks from a paracentesis are:

discomfort or pain at the insertion site
dizziness or lightheadedness (if a large amount of fluid is removed)
low blood pressure or shock (if a large amount of fluid is removed)
bruising or bleeding
infection
potential bowel injury

What the results mean

Excess fluid in the abdomen can be caused by:

injury to the abdomen
infection of the peritoneum (peritonitis)
scarring (cirrhosis) of the liver tissue
liver failure
cancer

What happens if a change or abnormality is found

The doctor will decide whether further tests, procedures, follow-up care or additional treatment is needed.

References

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