Paracentesis for Ascites
Ascites frequently occurs with cirrhosis of the liver, and it develops when the liver begins to fail. The condition is usually diagnosed during a physical exam but may be confirmed with a CT scan or ultrasound.
If a low-sodium diet and water pills are insufficient to treat ascites, you may need to have the fluid removed to relieve your symptoms. Paracentesis is a procedure that removes fluid (peritoneal fluid) from the abdomen through a slender needle. The collected fluid is then sent to a lab for analysis to determine what is causing the excess fluid. The most common reasons to perform paracentesis is to:
- Diagnose an infection
- Check for certain types of cancer
- Relieve pressure in the abdomen
- Improve kidney, bowel or respiratory function
Before the Procedure
Paracentesis is usually done in your doctor’s office, an emergency room or the X-ray department of a hospital. Before the procedure, your doctor will meet with you to discuss any allergies to medications or anesthesia and talk about what medications you are currently taking. If you have any bleeding problems or are taking blood thinners, nonsteroidal anti-inflammatory drugs (NSAIDs), or aspirin, you may have to stop taking those medications for a short time.
During the Procedure
Paracentesis generally takes about 20 to 30 minutes. It can be performed while you lie on your back or while sitting up, depending on the amount of fluid that needs to be removed. For larger volumes of fluid, you will lie on your back.
Your doctor will cleanse the abdomen, drape it with a sterile towel and apply numbing medicine where the needle will enter the abdomen. If a larger volume of fluid needs to be removed, the paracentesis needle may be hooked by a narrow tube to a vacuum bottle for the fluid to drain.
Your doctor will gently insert the needle into your abdomen and remove up to 4 liters of fluid. If more than 4 liters needs to be removed, you will likely be given supplemental fluids through an IV to prevent low blood pressure.
When the fluid has been removed, your doctor will remove the needle and bandage the entry site. Your pulse, blood pressure and temperature will be monitored over the course of an hour to ensure that your vital signs are normal. Your doctor may want to weigh you and/or measure the circumference of your abdomen after the procedure and compare them to previous measurements.
After the Procedure
There are several tests that can be done using the abdominal fluid that has been removed. Your doctor may want to have one or more of the following tests performed:
- Culture. This can be done to determine whether infection is present.
- Cytology. If abnormal cells are in the fluid, they may be cancerous.
- Cell counts. High white blood cell count may indicate inflammation, infection or cancer. Increased white blood cell count and a high amount of polymorphonuclear leukocytes (PMN) may point to a specific infection called spontaneous bacterial peritonitis (SBP).
- Glucose. Decreased glucose levels could be associated with infection.
- Lactate dehydrogenase (LDH). Increased levels of LDH could signify infection or cancer.
- Amylase. Increased amylase levels could be caused by pancreatitis or a hole in the intestine.
- Serum-ascites albumin gradient (SAAG). This test compares the level of protein in the peritoneal fluid to the level of protein in the blood. Increased protein levels in the fluid may indicate infection, nephrotic syndrome, cancer or pancreatitis.
Your doctor will give you instructions on how to care for your bandage and how to keep the wound clean. You may need to make changes in your eating and drinking habits such as:
- Reducing salt intake. This is very important to prevent recurrence of fluid buildup, particularly when the ascites is due to cirrhosis. You should limit your salt to 1.5 to 2 grams per day and eat at home so you can monitor your salt intake. Your doctor may suggest that you visit a nutritionist to help you create a low-sodium diet.
- Limiting your liquids. This is also important. You may need to drink less than one liter of fluids per day to help prevent ascites from recurring, and you may have to take water pills.
Call your doctor immediately if you have:
- Severe abdominal pain
- Increased tenderness or redness at the site of the paracentesis
- A fever higher than 100 degrees F (38 degrees C)
- Bleeding or excessive drainage from the site
Your doctor will let you know when you can resume your normal activities.
Paracentesis is a safe procedure, but there is always a small amount of risk including:
- Accidental penetration of the bladder, bowel or a blood vessel
- Internal bleeding
- Low blood pressure
- Decreased kidney function after fluid is removed