Percutaneous Liver Biopsy 

Percutaneous liver biopsy is a procedure in which a long needle is introduced through the skin, subcutaneous tissues, intercostal muscles, and peritoneum into the liver to obtain a specimen of liver tissue.^{[1, 2]} This procedure is usually performed on an outpatient basis. The patient is then observed for a few hours in the hospital or the ambulatory unit.

The liver biopsy needle used can be one of the following 3 types:

• Cutting needle
• Suction needle (discussed in this article)
• Spring-loaded needle

This topic focuses on the technical aspects of performing a percutaneous liver biopsy. For a more detailed discussion of the theoretical aspects, please see Diagnostic Liver Biopsy.

Initial diagnosis

• Evaluation of abnormal liver test results, if all other workup is unrevealing^[3]
• Determination of stage of fibrosis and grade of inflammation for chronic hepatitis B and hepatitis C^[4]
• Evaluation of autoimmune hepatitis
• Evaluation of a liver mass that does not exhibit typical imaging features of hepatocellular carcinoma (HCC)
• Quantitative estimation of iron in hemochromatosis
• Quantitative estimation of copper in Wilson disease
• Estimation of the severity of alcoholic liver disease
• Evaluation of drug toxicity
• Evaluation of the suitability of a donor liver for transplantation
• Diagnosis and staging of nonalcoholic fatty liver disease (NAFLD)/nonalcoholic steatohepatitis (NASH)
• Evaluation of unexplained jaundice
• Diagnosis of cholestatic liver disease
• Evaluation of infiltrative or granulomatous disorders
• Evaluation of liver injury from immunosuppressive agents (methotrexate)

Surveillance during treatment

• Follow-up evaluation while on antiviral treatment for chronic hepatitis C (rare)
• Monitoring of disease activity of autoimmune hepatitis during treatment (may assist in determining if therapy can be discontinued)

Posttransplant (liver)

• Diagnosis of acute cellular rejection
• Diagnosis of chronic rejection
• Diagnosis of recurrent hepatitis C
• Diagnosis of posttransplant lymphoproliferative disorder
• Diagnosis of cytomegalovirus (CMV) hepatitis
• Protocol biopsies to monitor for fibrosis or inflammation (particularly in patients who received liver transplants to treat liver failure in chronic hepatitis C)

• Uncooperative patient^[5]
• Inability to identify a suitable biopsy site by either percussion or ultrasonographic guidance
• Prolonged (>1.5) international normalized ratio (INR)^[6]
• Decreased platelet count (< 60,000/mm³)
• Bleeding diathesis (eg, hemophilia)
• Recent use (within the last 7 days) of aspirin or nonsteroidal anti-inflammatory drugs (NSAID) or antiplatelet class of medications
• Unavailability of blood products for transfusion
• Morbid obesity of patient
• Ascites
• No backup support available from surgery or interventional radiology in case of a complication
• Suspected hemangioma or hepatic echinococcal cysts
• Abdominal wall infection over the identified biopsy site
• Infection in the right pleural cavity or below the right hemidiaphragm
• Bowel overlying biopsy site (on ultrasound or other abdominal imaging)

• Local anesthesia with 1% or 2% lidocaine is used.
• Some anxious patients may require a small oral or intravenous dose of a benzodiazepine (eg, lorazepam).
• In rare cases, consideration may be given for the use of procedural sedation (eg, midazolam and fentanyl).
• Overnight fasting by the patient is usually required prior to the procedure.

• Patient consent form
• Sterile gloves
• Liver biopsy tray that contains the following items:

  • Core biopsy needle, preferably 16 gauge (ga), 4.5 inches
  • Povidone-iodine (eg, Betadine) solution
  • Formalin bottle (specimen container)
  • Injection needle, 21 ga, 1.5 inches
  • Injection needle, 25 ga, 1 inch
  • Sterile drape(s)
  • Saline solution (0.9%), 10-mL ampule
  • Surgical scalpel blade
  • Gauze pads, 3 X 3 inches
• Appropriate vials for cultures and special stains, if indicated

• The patient should be supine, with his or her right side near the edge of the bed.
• The patient’s right arm should be above his or her head. Feet should be angled across the bed to expand the intercostal space as much as possible.
• Adjust the height of the bed for comfort, usually at or slightly below the level of the elbows of the operator.

• Obtain written consent. Explain the benefits and risks of the procedure to the patient and make sure that he or she understands them well.
• Percuss over the right upper quadrant to choose the biopsy site. The biopsy site is usually located in the seventh or eighth intercostal space in the midaxillary line. The site can be further confirmed with either routine ultrasonography or a bedside portable ultrasound machine.^[7] Be sure to ascertain the direction and a safe depth for the biopsy needle, as shown in the image below. Also, be sure to eliminate the possibility of bowel juxtaposition along the biopsy tract. The video below depicts ultrasound-assisted percutaneous liver biopsy being performed. Ultrasonography of the liver. Hepatic parenchyma and blood vessels as seen on ultrasound.

  Ultrasound-assisted percutaneous liver biopsy. Video courtesy of George Y Wu, MD, PhD.
• Careful percussion can also be used to identify the site. Percuss along the midaxillary line and identify the point of maximal dullness at the end of maximal expiration by the patient, as shown below. This is usually found in either the seventh or eight intercostal space (corresponds to the second or third space above the right costal margin). Percussion over the liver.
• As in the image below, mark the identified site with a surgical pen. Marking the biopsy site.
• Use the swab sticks to prepare the field. For field preparation, the operator may wear nonsterile gloves. Apply the povidone-iodine solution in a centrifugal fashion, starting from the mark and moving out in concentric circles, as shown below. Use all 3 sticks sequentially. Preparing the field.
• Remove the cover of the biopsy tray to reveal its contents, as shown in the photograph below. Check to see that all the necessary items are available. Liver biopsy tray.
• Put on a sterile gown, cap, facial mask, and sterile gloves. Place sterile drape (found in the biopsy tray) as shown. Sterile drape application.
• Aspirate lidocaine (1% or 2%) in a syringe, as shown below. Aspirating lidocaine.
• Infiltrate the skin over the site using a 25-ga needle attached to the lidocaine-filled syringe, as depicted in the image below. Infiltrating the skin at the biopsy site.
• Identify the xiphoid process by palpating over the drape, and use some mark to easily refer to it later. In this photograph, a gauze piece is used as a marker (see left upper corner). Administer further local anesthesia using a 21-ga needle in both superficial and deeper planes, extending down to the capsule of the liver. The deeper injection should be done while the patient is holding his or her breath in maximal expiration. Deeper injection of local anesthetic.
• Using the second syringe from the tray, shown below, aspirate a minimum of 7-8 mL of sterile saline. Aspirating saline.
• Unscrew the needle on the second syringe and attach the liver biopsy needle to this syringe, as shown below. Switching to biopsy needle.
• Using the provided surgical blade, make a small nick at the site so the biopsy needle can pass more easily through the skin, as shown below. This nick should be made at the upper border of the lower rib in the intercostal space to avoid injuring the neurovascular bundle that courses close to the lower border of the ribs. Making a skin nick.
• The guard on the liver biopsy needle may be set beforehand based on the estimated depth required and the safety margin, which is based on the ultrasonographic results. Direct the needle as dictated by the ultrasonographic findings. If the percussion technique alone was used, the needle should be directed toward the xiphoid process and parallel to the ground. To avoid injury, introduce the biopsy needle in a similar fashion to that described for the blade in the previous step.
• After penetrating through the skin and superficial subcutaneous tissues, keep the plunger of the syringe retracted while the needle is advanced as shown below. A series of popping sensations may be felt as the needle passes through the various tissue planes. Flush small amounts of saline once the needle has crossed the tissue planes and is close to the liver capsule to get rid of any tissues that may be blocking the needle tip. Penetrating tissue planes.
• Reapply suction on the needle by pulling back on the syringe plunger, and instruct the patient to exhale completely and hold the breath in maximal exhalation. This expiration is requested to avoid injury to the lungs and the gall bladder as well as to bring the liver in close proximity to the thoracic wall.
• At this time, maintain suction on the syringe while pushing the needle into the liver to the depth and direction estimated previously and quickly removing the needle as shown below. This whole movement should not take more than 1 second and should be smooth in and out. The liver biopsy sample is thus obtained within the saline-filled syringe. Biopsy needle inside the liver.
• Unscrew the needle from the syringe. Pull the plunger back and gently take it off the syringe, as depicted in the image below, rather than trying to push the specimen forward through the opening of the syringe, which damages the specimen. Taking the plunger out.
• Empty the contents of the syringe into the formalin-containing bottle. Notice the liver biopsy sample in the bottle (white arrow in the image below). Cap the bottle tightly and then look through the side of the bottle to ascertain the approximate size of the sample. A sample about 1.5 cm in length and 1-2 mm in width is generally considered adequate. Transferring liver biopsy specimen to the formalin bottle.
• Label the bottle. A liver biopsy sample thus obtained should be hand-delivered to the pathology laboratory rather than sending through the pneumatic tube system to avoid the small chance of it getting lost.
• Apply pressure to the biopsy site for a few minutes, and then apply an adhesive bandage at the site. Instruct the patient to lie on the right side (as shown) for at least 2 hours. Patient lying on right side.
• The postprocedure orders sheet should be filled out at this time. Vital signs (blood pressure, heart rate, and pain level) should be obtained every 15 minutes for the first hour, every 30 minutes for the next hour, and, subsequently, every hour until discharge. A postprocedure observation time of 2 hours is considered adequate if no complications arise.^[8] The patient should be observed closely for any symptom or sign of a complication.^[9]

• Proper identification of the biopsy site is of paramount importance.
• The intrahepatic phase of the needle should be 1 second or less.
• Limit the needle passes through the liver to no more than 3; a higher number of passes has been associated with increased risk of bleeding.

• Pain at the biopsy site or in the right shoulder (referred pain)

  • Most common adverse effect
  • Occurs in 25% of patients
  • Should not require more than 1 dose of an analgesic
• Hypotension

  • Commonly caused by vasovagal reaction
  • Common cause of hospitalization (together with pain)
  • May be a sign of hemorrhage
• Hemorrhage^{[10, 11]}

  • Manifests as hypotension, tachycardia, and abdominal pain, usually within 3-4 hours of biopsy
  • Presentations include the following:
    • Subcapsular hemorrhage (usually asymptomatic; may cause pain)
    • Intrahepatic hemorrhage (usually asymptomatic)
    • Intraperitoneal hemorrhage (most serious bleeding complication; rare)
    • Hemobilia (very rare; 4 cases in a series of more than 68,000 patients)
• Unintentional biopsy of other organs, such as lung, kidney, or colon (rare)
• Biliary peritonitis (rare)
• Pneumothorax or hemothorax (rare)^[12]
• Transient bacteremia (mostly inconsequential)
• Death (death rate 1 in 10,000-12,000 patients)^{[13, 14]}

These guidelines are modified from the American Gastroenterological Association’s 1989 position statement.^[15]

1. The patient must be able to easily return to the hospital where the procedure was performed within 30 minutes of developing any adverse symptoms.
2. A reliable individual must be available to stay with the patient during the first night after the liver biopsy and provide care and transportation to the hospital, if necessary.
3. The patient should not have any preexisting serious medical problems that might increase the risk of complications from the biopsy. Such problems may include encephalopathy, ascites, liver failure with severe jaundice, significant extrahepatic obstruction, significant coagulopathies, or serious comorbidities such as severe congestive heart failure. Also, patients should not be very old, very young, or so anxious that they require sedation.
4. The facility where the biopsy is to be performed should have an approved laboratory, blood banking unit, easy access to an inpatient bed, and personnel to monitor the patient for 6 hours after the biopsy.
5. The patient should be hospitalized after biopsy if any evidence exists of bleeding, bile leak, pneumothorax, or other organ puncture. Hospitalization is suggested if the patient’s pain requires more than 1 dose of an analgesic in the first 4 hours after the biopsy.