Liver Biopsy (Percutaneous Liver Biopsy)
What is a liver biopsy?
A liver biopsy is a procedure that involves obtaining a small piece of liver tissue, which is then analyzed in the laboratory. It may be recommended to help establish a diagnosis or to determine the severity of injury from a disease that has already been diagnosed. A liver biopsy is often an essential piece of information that doctors need to help guide your care.
Liver biopsies are most commonly performed “percutaneously” (through the skin). As a result, most patients can go home within two to four hours of the procedure. Other methods of obtaining liver tissue may be required in circumstances in which the percutaneous approach is undesirable or unsafe.
The suggestion by a doctor that you should have a biopsy is bound to produce anxiety in most people. The word “biopsy” brings up concerns about cancer, and additionally most people worry about whether the biopsy will hurt. The technique for percutaneous liver biopsy has been performed since the 1950s with a high degree of safety. Every effort will be made to make your biopsy as comfortable as possible.
WHY IS LIVER BIOPSY PERFORMED?
As a general rule, a liver biopsy is recommended only when the results would influence a management decision. Some of the more common indications are in patients with:
- A variety of different types of liver diseases, such as chronic hepatitis B or C, primary biliary cirrhosis, primary sclerosing cholangitis, autoimmune hepatitis, nonalcoholic steatohepatitis (NASH), hemochromatosis or Wilson’s disease. A biopsy can provide information about the severity of liver injury.
- Unexplained liver disease or abnormal liver function tests (blood tests that reflect injury to the liver)
- Monitoring the liver following a liver transplant
A liver biopsy may also be helpful in people with unexplained fevers, those with certain rare metabolic diseases, and a variety of other less common disorders.
WHO PERFORMS THE LIVER BIOPSY?
In most hospitals, liver biopsies are performed by gastroenterologists, hepatologists, radiologists, and occasionally by surgeons at the time of abdominal operations.
WHAT PREPARATIONS ARE DONE BEFORE LIVER BIOPSY?
Prior to your liver biopsy, your doctor will check blood tests that reflect how well your blood clots. Normal blood clotting is important to prevent bleeding after the biopsy. You should not take medications that can increase the risk of bleeding. These include aspirin, aspirin-containing compounds or other nonsteroidal anti-inflammatory drugs (NSAIDs) such as ibuprofen (eg, Motrin®, Advil®, naproxen (eg, Aleve®), blood thinning medications such as warfarin (Coumadin®), certain medications for people with heart conditions (such as abciximab [Reopro®], dipyridamole [Persantine®], ticlopidine [Ticlid®], and clopidogrel [Plavix®]), and some naturalistic therapies (such as fish oil or ginkgo balboa). It is important to know that NSAIDs are contained in a variety of over-the-counter preparations, so you might not be aware that you are taking them. The best thing to do is to show your doctor the complete list of medications that you are taking including over-the-counter medications. Your doctor can recommend when and how you can interrupt taking these drugs so that your biopsy can be performed safely.
It is common practice to perform an ultrasound examination of the liver and gallbladder area so that the physician who does the biopsy can confirm that the chosen site is appropriate. An ultrasound is a painless test in which sound waves are used to visualize the liver and related structures.
The day of the biopsy you may be instructed to have nothing to eat or drink after midnight before the procedure or to have a light breakfast only, such as tea or coffee and toast. Some doctors recommend having a small amount of fat (such as butter or margarine) with your breakfast, which will empty the gallbladder, possibly making it less likely that the gallbladder will be injured during the biopsy.
You will need to arrange to have someone accompany you to your home after the biopsy since you may receive meditations that will temporarily impair your ability to drive. A friend or family member can also help pass the time during the few hours of observation following the biopsy.
Antibiotics are not given routinely prior to a liver biopsy. Exceptions are patients with primary sclerosing cholangitis, in whom antibiotics are frequently given before the biopsy to lessen the risk of infection.
ARE THERE ANY CONDITIONS IN WHICH A PERCUTANEOUS LIVER BIOPSY SHOULD NOT BE PERFORMED?
Some conditions make it unsafe to perform a percutaneous liver biopsy. In general, these include:
- An uncooperative or confused patient
- Significant blood clotting abnormalities
- Severe anemia (low blood count)
- A large amount of fluid in the abdomen (ascites)
- Local skin infection at the biopsy site.
WHAT IS THE PROCEDURE LIKE?
When you arrive for the biopsy (usually in the early morning), the team of doctors and nurses involved in your procedure will review your medical history, including any medications you take and any allergies to medications. In some institutions a nurse will start an intravenous line (put a needle in a vein in your arm) so that fluid and medications can be administered if needed. Putting in an intravenous line feels just like a pin prick, no worse than having your blood drawn.
The doctor will review the procedure with you and ask you to sign a consent form. The consent form will summarize the reasons for the biopsy, risks, and alternatives.
You may be given analgesic and sedative medication prior to the procedure to minimize discomfort and anxiety, although many doctors (and some patients) prefer not to use them because your cooperation is needed during the liver biopsy.
During a percutaneous biopsy you will be lying on your back near the right edge of the bed. Your right arm will be under your head. The doctor will locate the best site for the biopsy by tapping (called percussing) with his finger against the side of your chest after you have completely exhaled (you breathe in and breathe out and hold your breath). The site will be marked with a felt pen.
Your skin will be cleansed with alcohol and an iodine solution, and the area will be draped with sterile towels. A local anesthetic will be injected into the skin; you will feel this as a burning sensation. A tiny incision will be made into the skin so that the needle for biopsy will pass through easily.
Most doctors perform a liver biopsy at “end-expiration” (ie, when you have completely breathed out). This has the effect of making the right lung smaller and bringing the liver upward toward the chest, thereby making it less likely that the liver biopsy needle will injure any organs adjacent to the liver. To help assure that the biopsy is performed during end-expiration, your doctor may rehearse controlled breathing with you by asking you to breathe in deeply and then exhale completely while holding your breath out until your doctor counts to four. At the time of the biopsy it is very important for you to cooperate with breathing instructions.
The biopsy itself takes only one second, during which time the biopsy needle is passed quickly in and out of the liver, suctioning a small cylindrical sample of liver tissue. Some doctors use automated liver biopsy devices, which can make a clicking sound when the biopsy needle is deployed. You will be told to resume breathing after the biopsy. A small bandage will be applied to the biopsy site; stitches are not needed. You will be asked to lie on your right side for two hours to place pressure against the biopsy site to decrease the possibility of bleeding.
WHAT CAN I EXPECT AFTER A LIVER BIOPSY?
Following the biopsy, you will be asked to lie on your right side for two hours. A nurse will check your blood pressure and pulse every 15 minutes and ask how you are feeling. Afterward, you will be monitored less frequently for another two to six hours. Many people watch television, a video, read, or talk to friends or family. Lunch is often provided.
WHAT ARE POSSIBLE COMPLICATIONS?
A liver biopsy is a very safe procedure when performed by experienced operators. Only two to three percent of patients require hospitalization after a liver biopsy due to complications. Mortality from this procedure is very rare, occurring in only 1:12,000 persons. The following are some of the more common complications that have been described.
- Discomfort – Approximately 25 percent of patients experience discomfort at the biopsy site, right upper abdomen, or right shoulder after a liver biopsy. The discomfort is usually dull, mild in nature, may be worse during breathing, and lasts for only a short duration (a few hours to less than 24 hours), although patients have uncommonly noted mild discomfort lasting for longer. The discomfort usually responds to mild analgesics such as acetaminophen (Tylenol®). Note that Tylenol in doses of less than 2g given over 24 hours (this equals four extra strength tablets or capsules) is safe in patients with liver disease. Less commonly the pain can be more intense, requiring stronger medications. Ongoing severe pain should alert your doctor to the possibility of a more serious problem that requires evaluation.
- Low blood pressure – Low blood pressure immediately after a liver biopsy (occurring in about 10 to 20 percent of patients) is usually due to a “vasovagal” (pronounced Vay-Zo-Vay-Gal) reaction during which the blood vessels in the body dilate and the heart rate slows. This reaction is similar to what occurs when a patient faints. The reaction can be reversed with medications if needed, but more often responds to intravenous fluids, pain medications, or observation. Persistent low blood pressure or a falling blood pressure may indicate bleeding.
- Bleeding – Significant bleeding after a liver biopsy occurs in approximately 0.3 percent of biopsies (3 in 1,000). Bleeding usually becomes apparent within three to four hours. If bleeding occurs, you may require a transfusion. The bleeding often stops on its own. Surgery or angiography (a procedure in which the bleeding site is identified and treatment to stop the bleeding is carried out) may be required if the bleeding is severe or does not stop on its own.
- Bile peritonitis – The liver and ducts within it contain bile, a substance that helps digest your food. Leakage of bile after a liver biopsy can cause irritation of the lining of the abdomen, a condition called “bile peritonitis”. Bile peritonitis occurs in less than 1 in 1,000 biopsies. It usually resolves on its own. Removal of the gallbladder may be required if the leakage is due to gallbladder injury.
- Infection – Bacteria can be released into the blood in people who have certain forms of liver disease in which the bile ducts are blocked (such as primary sclerosing cholangitis). Infection of the biopsy site itself is rare.
- Perforation – The biopsy needle may inadvertently pierce organs that are adjacent to the liver. These include the lungs, kidney, small intestine, and gallbladder. Fortunately, this does not usually cause a serious problem. However, perforation of the gallbladder may cause bile peritonitis.
- Reactions to medications – Some people receive pain medications or sedatives before or after liver biopsy. An adverse reaction to these medications (such as an allergic reaction, low blood pressure, or difficulty breathing) is possible, but serious reactions are quite uncommon. When they occur, they can be treated promptly. Reactions to the local anesthetic (usually lidocaine) are rare.
ARE THERE ANY RESTRICTIONS AFTER THE BIOPSY?
In addition to resting the day of the biopsy, you should plan to take it easy for the next five to seven days. In general you will be instructed to restrict heavy lifting (no more than 15 to 20 pounds) for a week, avoid blood thinning medication for several days, and to call your doctor with any concerning symptoms such as:
- Severe pain at the biopsy site, or severe shoulder pain
- Shortness of breath
- Chest pain
- Bleeding from the biopsy site
- Abdominal pain
- Heart palpitations.
WHEN WILL THE RESULTS OF THE BIOPSY BE AVAILABLE?
Most often the biopsy report will be available within a week. Patients usually have a follow-up appointment to discuss the results of the biopsy and what treatment (if any) is needed.