Paracentesis: How Abdominal Fluid (Ascites) Is Drained

What Is Paracentesis and Why Is It Performed?

Paracentesis (also called abdominal tap or ascites drainage) is a medical procedure where a thin catheter is inserted through the abdominal wall to remove excess fluid (ascites) from the peritoneal cavity. It is performed to relieve symptoms such as breathing difficulties, abdominal discomfort, and reduced mobility, or to analyze the fluid for diagnostic purposes.

The abdomen (also known as the belly or stomach area in everyday language) contains many vital organs including the liver, stomach, intestines, and gallbladder. The space surrounding these organs is called the peritoneal cavity, which normally contains only a small amount of fluid to lubricate the organs. When abnormal amounts of fluid accumulate in this space, the condition is called ascites.

Ascites can develop due to various underlying conditions, with liver cirrhosis being the most common cause, accounting for approximately 75% of cases. Other causes include heart failure, kidney disease, cancer (particularly ovarian, pancreatic, and liver cancers), infections, and inflammatory conditions. The fluid accumulation can cause significant discomfort and interfere with normal breathing and daily activities.

Paracentesis serves two main purposes. Therapeutic paracentesis aims to relieve symptoms by removing large volumes of fluid, often several liters at a time. Diagnostic paracentesis involves removing a smaller sample of fluid for laboratory analysis to determine the cause of fluid accumulation or to detect infection. In many cases, the procedure serves both purposes simultaneously.

Common Causes of Ascites

Understanding why ascites develops helps explain why the fluid often returns after drainage. The most common causes include:

• Liver cirrhosis: Scarring of the liver leads to increased pressure in the portal vein system (portal hypertension), causing fluid to leak into the abdominal cavity. This accounts for about 75% of ascites cases
• Heart failure: When the heart cannot pump blood effectively, fluid backs up in the body, including the abdomen
• Cancer: Malignant cells can irritate the peritoneum, causing fluid production, or block lymphatic drainage
• Kidney disease: Advanced kidney disease leads to fluid retention throughout the body
• Infections: Tuberculosis and other infections can cause ascites, particularly in developing countries
• Pancreatitis: Inflammation of the pancreas can lead to fluid accumulation

How Should I Prepare for Paracentesis?

Preparation for paracentesis typically includes blood tests to check clotting factors, reviewing your medications (especially blood thinners), and possibly an ultrasound examination. You can usually eat and drink normally before the procedure. Showering on the morning of the procedure helps reduce infection risk.

Your healthcare team will provide specific instructions based on your individual situation, but general preparation guidelines help ensure a safe and successful procedure. The preparation process is designed to minimize risks and optimize outcomes.

Before the procedure, you will typically need to have blood tests to check your blood clotting ability (coagulation profile). This is important because the procedure involves inserting a needle through tissues, and your blood needs to be able to clot normally to prevent excessive bleeding. Tests usually include prothrombin time (PT), international normalized ratio (INR), and platelet count.

If you take blood-thinning medications (anticoagulants), you must inform your healthcare team well in advance. Depending on the medication and your medical situation, you may need to temporarily stop or adjust the dose before the procedure. Common blood thinners include warfarin, heparin, dabigatran, rivaroxaban, apixaban, and aspirin. Never stop taking prescribed medications without consulting your doctor first.

What to Expect Before the Procedure

On the day of the procedure, several steps help ensure everything goes smoothly:

• Eating and drinking: You can typically eat and drink normally before paracentesis, unlike many other medical procedures
• Hygiene: Shower on the morning of the procedure to help reduce infection risk at the puncture site
• Clothing: Wear comfortable, loose-fitting clothing that allows easy access to your abdomen
• Empty your bladder: You may be asked to urinate before the procedure to reduce the risk of accidentally puncturing a full bladder
• Inform staff of allergies: Tell your healthcare team about any allergies, particularly to local anesthetics or latex

Some patients may require additional preparation depending on their underlying conditions. For example, if you have significant kidney problems, your team may want to check kidney function. If infection is suspected, additional precautions may be taken. Your healthcare provider will explain any specific requirements for your situation.

How Is the Paracentesis Procedure Performed?

During paracentesis, a thin drainage catheter is inserted through the skin into the abdominal cavity under local anesthesia. The doctor may use ultrasound to locate the fluid and determine the best insertion point. Fluid drains through the catheter into collection bags, which may take 1-3 hours depending on the volume. You may receive intravenous albumin during large volume drainage to prevent circulatory problems.

Understanding what happens during the procedure can help reduce anxiety and allow you to participate in your care. The procedure is typically performed by a physician in a hospital, clinic, or outpatient setting, and follows standardized steps to ensure safety and effectiveness.

Step-by-Step Process

The paracentesis procedure typically follows these steps:

1. Positioning and Assessment: You will be positioned comfortably, usually lying on your back with the head slightly elevated, or sometimes turned slightly to one side. The doctor may examine your abdomen by touch (palpation) to assess the amount and distribution of fluid.

2. Ultrasound Examination: In many cases, the doctor uses ultrasound imaging to visualize the fluid collection. This imaging helps determine exactly how much fluid is present and identifies the safest location for needle insertion, avoiding organs and blood vessels. Ultrasound guidance has significantly improved the safety of the procedure.

3. Skin Preparation: The healthcare team cleans and sterilizes the insertion site, typically located in the lower left quadrant of the abdomen (below and to the side of the navel). A sterile drape is placed around the area to maintain a clean field.

4. Local Anesthesia: You receive a local anesthetic injection to numb the skin and deeper tissues. You may feel a brief stinging sensation during the injection, but this quickly subsides as the area becomes numb. The anesthesia typically takes effect within a few minutes.

5. Catheter Insertion: Once the area is numb, the doctor makes a small incision (a few millimeters) and inserts the drainage catheter through the abdominal wall into the fluid collection. You may feel pressure during insertion but should not feel significant pain.

6. Fluid Drainage: The fluid flows through the catheter into sterile collection bags. The drainage process may take 1-3 hours depending on how much fluid needs to be removed. During this time, your vital signs (blood pressure, heart rate) are monitored. Healthcare staff regularly check on you and may reposition you if needed to optimize drainage.

7. Albumin Infusion: If large volumes of fluid are being removed (typically more than 5 liters), you will likely receive intravenous albumin. Albumin is a protein that helps maintain blood pressure and prevent fluid from shifting too rapidly in your body. This infusion is given through a small catheter in your arm.

8. Catheter Removal and Dressing: Once drainage is complete, the catheter is removed. A bandage or dressing is applied to the wound site. This dressing helps absorb any fluid that may leak from the puncture site over the next day or two.

What Tests Are Done on the Fluid?

The fluid removed during paracentesis can provide valuable diagnostic information. Common laboratory tests include:

• Cell count and differential: Checks for infection by counting white blood cells
• Albumin and protein levels: Helps determine the cause of ascites (serum-ascites albumin gradient or SAAG)
• Culture: Tests for bacterial infection (spontaneous bacterial peritonitis)
• Cytology: Examines cells for signs of cancer
• Amylase: Can indicate pancreatic problems
• Other tests: Depending on suspected cause, additional tests may be ordered

What Should I Expect After Paracentesis?

Most people can go home the same day as the procedure. You should avoid heavy lifting on the day of the procedure but can eat and drink normally. The wound typically heals within a few days, though some fluid leakage from the puncture site is normal. You will receive instructions on wound care and warning signs to watch for.

Recovery from paracentesis is generally straightforward, with most patients experiencing immediate relief from their symptoms. However, proper aftercare helps ensure optimal healing and allows you to recognize any potential complications early.

Immediately after the procedure, you will be monitored for a period (usually 1-2 hours) to ensure your vital signs are stable and you are not experiencing any adverse reactions. During this time, the healthcare team will check your blood pressure, heart rate, and the puncture site. Once you are stable, you will receive discharge instructions.

Recovery Timeline and Care Instructions

Understanding the normal recovery process helps you know what to expect and when to seek help:

Same day: Most patients feel significantly better immediately after the procedure due to reduced abdominal pressure. You can eat and drink normally. Avoid heavy lifting or strenuous activity for the rest of the day. You may feel tired, which is normal.

First few days: Some fluid may leak from the puncture site, which is normal. The dressing absorbs this fluid and can usually be removed after 2-3 days. The wound typically heals within a few days, though it may take longer for some people.

First week: Gradually resume normal activities. If you received a large volume drainage, your healthcare team may schedule a follow-up appointment to check on your condition and discuss ongoing management.

Wound Care Instructions

• Keep the dressing clean and dry for the first 24-48 hours
• After removing the dressing, keep the area clean and watch for signs of infection
• It is normal for small amounts of fluid to leak from the puncture site initially
• If leakage continues beyond a few days, contact your healthcare team
• Avoid soaking in baths or swimming until the wound has fully healed

What If the Fluid Comes Back After Paracentesis?

Ascites fluid often reaccumulates because paracentesis treats the symptom (fluid buildup) but not the underlying cause. The rate of fluid return depends on your underlying condition. Your healthcare team will discuss strategies to slow reaccumulation, which may include dietary changes (salt restriction), diuretic medications, treating the underlying disease, or considering procedures for recurrent ascites.

One of the most common questions patients have is whether the fluid will return after drainage. Unfortunately, in many cases, the answer is yes—at least to some degree. This is because paracentesis removes the accumulated fluid but does not address the underlying condition causing the fluid to accumulate in the first place.

The speed at which fluid reaccumulates varies greatly depending on the underlying cause and its severity. Some patients may go weeks or months before needing another paracentesis, while others may need more frequent drainage. Understanding this helps set realistic expectations and plan for ongoing care.

Strategies to Reduce Fluid Reaccumulation

Your healthcare team will work with you to slow the rate of fluid buildup using several approaches:

Dietary modifications: Reducing sodium (salt) intake is often the first recommendation. High sodium intake causes the body to retain fluid. Most patients with ascites are advised to limit sodium to less than 2,000 mg (2 grams) per day, and sometimes even lower. This can be challenging as many processed and restaurant foods contain high amounts of sodium.

Diuretic medications: Diuretics (water pills) help your kidneys remove excess fluid. Common medications include spironolactone and furosemide. Your doctor will carefully balance these medications to remove fluid without causing dehydration or electrolyte imbalances.

Treating the underlying condition: If liver disease is the cause, treatments may include abstaining from alcohol, antiviral medications for hepatitis, or in severe cases, evaluation for liver transplantation. Heart failure treatment, cancer treatment, or management of other underlying conditions can all help reduce ascites.

TIPS procedure: For patients with liver disease and recurrent ascites that does not respond to medications, a procedure called TIPS (transjugular intrahepatic portosystemic shunt) may be considered. This creates a new pathway for blood flow in the liver to reduce portal pressure.

Indwelling catheters: For patients with malignant (cancer-related) ascites or those who need very frequent drainage, a semi-permanent drainage catheter may be placed. This allows fluid to be drained at home, improving quality of life.

What Are the Risks and Complications of Paracentesis?

Paracentesis is generally very safe with a complication rate of less than 1%. Possible risks include infection at the puncture site, bleeding, bowel perforation (very rare with ultrasound guidance), and temporary dizziness due to fluid shifts. The use of ultrasound guidance and proper technique has made serious complications extremely uncommon.

While paracentesis is considered a safe procedure, as with any medical intervention, there are potential risks. Understanding these risks allows you to make an informed decision and recognize problems if they occur. Importantly, the benefits of the procedure almost always outweigh the risks for patients who need it.

Potential Complications

Complications from paracentesis are uncommon, but may include:

Infection: Any procedure that breaks the skin carries a small risk of infection. Signs of infection include fever, increasing pain, redness, or pus at the puncture site. Proper sterile technique minimizes this risk. Spontaneous bacterial peritonitis (SBP) is a serious infection of the ascites fluid that can occur independently of the procedure but is usually why diagnostic paracentesis is important.

Bleeding: Minor bleeding at the puncture site is common and usually stops on its own. Significant bleeding requiring treatment is rare, especially when clotting studies are checked beforehand and blood thinners are appropriately managed.

Bowel or organ perforation: There is a theoretical risk of puncturing the bowel or other abdominal organs. This risk has been dramatically reduced by the routine use of ultrasound guidance, which allows the doctor to see exactly where they are inserting the needle.

Circulatory changes: Removing large volumes of fluid can cause fluid shifts in the body, potentially leading to low blood pressure, dizziness, or kidney problems. This is why albumin infusion is given during large volume paracentesis—it helps maintain blood volume and prevent these complications.

Persistent leakage: Sometimes fluid continues to leak from the puncture site for several days. This is usually minor but can occasionally require additional treatment if it persists.

How Can I Participate in My Care?

You have the right to be involved in decisions about your care. This means understanding the information provided by your healthcare team, asking questions when needed, and making informed choices about your treatment. If you have difficulty communicating, interpreter services and other accommodations are available.

Being an active participant in your healthcare leads to better outcomes and greater satisfaction with care. Your healthcare team wants you to understand your condition and feel comfortable with the decisions being made about your treatment.

Before any procedure, you should receive clear explanations about what will happen, why it is being done, what the alternatives are, and what risks are involved. If you do not understand something, ask your healthcare team to explain it again or in a different way. There are no "stupid questions" when it comes to your health.

Your Rights as a Patient

• Receive information in a way you can understand
• Ask questions and have them answered honestly
• Know the benefits, risks, and alternatives to any procedure
• Have time to make decisions (except in emergencies)
• Change your mind about treatment
• Have a family member or friend present for support
• Access interpreter services if needed
• Request accommodations for disabilities

If you have a hearing impairment, visual impairment, or other communication needs, let your healthcare team know so they can provide appropriate accommodations. Many facilities offer interpreter services for various languages as well as sign language interpreters.