Liver biopsy | Procedure skills OSCE Station
This guide covers step by step explanation of how to approach a clinical procedure station on liver biopsy in children.
We will discuss the station in two parts.
- Theory about liver biopsy for Viva question
- Confirming Indication and ruling out Contraindication
- Sedation and pain management
- Equipment - Liver biopsy needles
- Procedure
- Post-procedure care
- Complications
- Mock OSCE - Practise station
Indications of liver biopsy
Diagnostic
A. Liver diseases
- Etiology neonatal cholestasis
- Etiology of acute liver failure
- Autoimmune hepatitis
- Cirrhosis of liver
- primary sclerosing cholangitis
- Cryptogenic cirrhosis
- Biliary cirrhosis
B. Storage disorder
- Hemochromatosis
- Glycogen storage disease
- Wilson’s disease
C. Malignancy
- Leukemia lymphoma Wilm's tumor
- Hepatoblastoma nephroblastoma
D. Infiltration
- Tuberculosis
- Sarcoidosis
E. Infection
- CMV
- Herpes
Prognostic
- Staging of cirrhosis
- Evaluation of pre-transplant living donor
- Evaluation of post-transplant patient to assess rejection vs. infectious etiology
Management oriented
Evaluation of the effectiveness of therapies for liver diseases eg, autoimmune hepatitis
Contraindications
Absolute
- Bleeding diathesis
- Vascular lesion
Relative
- Severe hepatocellular jaundice
- Infection of liver, peritoneum, biliary tract, right lung base, rt. Subhepatic access
- Hydatid cyst of liver
- Hemangioma of liver
- Chronic passive congestion of the liver
- Gross ascites
Obtaining Consent for biopsy
- Introduce yourself and your role
- Confirm the identity of the patient using their name and date of birth.
- Focus on ICE - Ideas, concerns, and expectations.
Ideas?
- Do you know what procedure is planned today?
- What do you understand about the procedure?
Obtain consent using the above points like indications, how it is done, complications, and post-procedure care and monitoring, but in a brief time. Do not get too much technical since time is of the essence.
Explain that the blood test (coagulation profile) that was done before the procedure is normal and you can go ahead.
Concerns?
Are you worried about anything, I should talk about?
Expectations?
Would you like to know anything more? For example, this can be 'How long will he/she be staying in hospital?
Pro tips - Do not forget to take consent about sedation as well in case it is required. Enquire if they have any questions. Make sure the patient or relatives have understood.
Prerequisites
- Consent
- Get a baseline LFT so as to avoid difficulty in differentiating the compounding damage by the procedure.
- Coagulation profile and platelet count must be done to assess the risk of bleeding and appropriate blood product transfusion before the procedure.
Pain management and sedation
You must mention pain management and sedation prior to the procedure. Take consent for sedation along with procedure consent. Remember they are different.
You can use ketamine, fentanyl, or propofol for sedation. ketamine is an excellent analgesic and the onset of action is quick.
More on pain pathways and management hereA local anesthetist is very important and must be mentioned during OSCE station since it decreases the need for systemic analgesia and sedation thus reducing the side effects.
Premedicate with atropine if necessary.
Various liver biopsy needles
It is better to be through with the liver biopsy needles since these can also be asked in instrument viva. Get familiar with all these in your pathology rotation.
Cutting type
- Vim-Silverman cutting needle
- True cut biopsy
Aspiration type
- Menghini’s aspiration biopsy
- Klatskin biopsy needle
Vim Silverman needle
It has 3 parts (Refer to the image)
- cannula for puncture and insertion
- Stylet/trocar - stays inside while puncturing and inserting, once the cannula is positioned, it is removed.
- Bifid needle - This is longer than the stylet and protrudes out of the cannula. It has a very sharp cutting edge and has a longitudinal groove to retain the liver tissue.
How liver biopsy is done?
A blind biopsy is a classic method for liver biopsy. Image-guided biopsy is a standard procedure now and ensures safety. Mention that if the situation permits.
In the OSCE station, usually, a blind liver biopsy is asked to test your clinical skills. However, remember, real-time image-guided liver biopsy is what is recommended.
Blind Method
This method can be used for diffuse liver pathology. However, you can not target a particular area which can be easily done using ultrasound guidance.
In the Blind procedure, the upper and lower border of the liver is assessed using palpation and percussion and the insertion site is marked.
How to perform an abdominal examinationSite
For the blind method, the usual site for biopsy is the 9th or 10th intercostal space in the midaxillary area on right.
Position
Patient laying down supine with arms behind the head. In older children, they can be asked to hold their breath in inspiration so that the liver is pushed down.
Procedure
- The cannula with stylet inside (for Vim Silverman needle) is inserted into the liver 2 to 3 cm deep at the puncture site.
- The stylet is then removed and the bifid needle )refer to image) is inserted.
- The bifid needle projecting out of the cannula is rotated 360 degrees to remove a small piece of liver tissue between the prongs.
- The bifid needle is then withdrawn inside the cannula and removed.
- The collected sample is placed in a container with formalin.
- The puncture site is sealed.
- Place NPO orders
- Monitor vital
- Frequent monitoring sat for eg every 15 mins for first hours, which can be relaxed in later hours. Total duraition aprox, 4 to 6 hrs.
Pro-tip: Always use the upper border of the rib to puncture so as to avoid damage to the neurovascular bundle. I always remember this by "crawl on the rib". The same applies to thoracic paracentesis.
Complications
- Pain and discomfort - most common -must mention
- Hemorrhage
- Infection
- Injury to liver, gallbladder, colon, kidney, blood vessels & nerves
- Precipitation of hepatic coma
Mock station - Liver Biopsy
Perform a liver biopsy on this 9-year-old who has prolonged unconjugated hyperbilirubinemia and findings of cirrhosis on ultrasound. The etiology is not determined yet despite blood investigation. Explain the steps alongside, while you perform the procedure.
History taking Jaundiced infant.Hepatosplenomegaly
- Ensures consent has been taken.
- Ensures IV access, analgesia, and sedation if needed in younger kids especially.
- Washes hands, wears PPE, and takes aseptic precautions.
- Prepares skin with a solution containing at least 75% alcohol and 2% or more chlorhexidine.
- Creates sterile area with sterile sheets
- Keeps biopsy needle, and consumables including transfer medium (formalin container) inside the sterile area
- Marks the picture site
- Infiltrates local anestetist
- Performs procedure as explained above (classical method)
- Collects the sample and asks to transfer to histopathology
- Discard biomedical waste as per guidance
- Mentions post-procedure care
- Keep supine
- NPO for 4 to 6 hours
- Ensures vital monitoring including blood pressure.
Tip: Consumables like a sterile sheet, cannula etc may not be always provided, in which case just speak about the recommended steps. "I will now create a sterile field with sterile sheets around the puncture site"
How to discard biomedical waste?
Refer to everything about new biomedical waste management
Modify the conversation as per the details given to you rather than strictly following the format. Say for example, If it is mentioned that the consent has been already taken. Do not mention it, to the examiner.
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Author
Ajay Agade | DNB(Pediatrics), FNB(Pediatric Intensive Care), Fellowship in Pediatric pulmonology and LTV
Ajay is a Paediatric Intensivist, currently working in Pediatric Pulmonology & LTV at Great Ormond Street Hospital NHS, London