What is ERCP?
Endoscopic retrograde cholangiopancreatography (ERCP) is an endoscopic procedure used to look at or treat the bile ducts, pancreatic ducts and the gallbladder.
During the ERCP, a thin, flexible, and hollow tube with a camera attached at one end, called an endoscope, is inserted through the mouth and carefully moved into the digestive tract. The endoscope goes from the mouth to the oesophagus, stomach, and then lastly to the duodenum, the first part of the small intestine.
Once at the duodenum, it is then used to find the papilla, which is the opening of the bile duct into the duodenum.
At the papilla, a small flexible tube, called a guidewire, is passed down the endoscope and into the papilla to reach the bile duct and pancreatic ducts. A dye is then injected into the ducts, and x-ray images are captured as the dye causes these various passages to light up on the x-ray.
- Bile ducts — tubes that arise from the liver to carry bile from the liver to the gallbladder and duodenum. These bile ducts merge into a common bile duct.
- Pancreatic ducts — tubes that transport pancreatic juice from the pancreas to the duodenum.
ERCP is a relatively safe procedure. However, there is a risk of complications such as:
- Pancreatitis
- Pain
- Infection
- Bleeding
- Having an abnormal reaction to the sedatives used
- Tears/damage to surrounding structures in the ERCP
Why do I need ERCP?
Certain presentations may be an indication for ERCP. These include, but are not limited to:
- Patients presenting with jaundice (which may include having yellow skin/eyes, pale stools, and dark, tea-coloured urine)
- Causes include gallstones, strictures, tumours, trauma and injury to the bile duct, Sphincter of Oddi dysfunction
- Patients with pancreatitis
- Patients of which there is high suspicion for any hepatobiliary tract abnormalities
Diagnostic purposes
ERCPs may be used to diagnose and evaluate certain conditions:
- Biliary tract abnormalities
- Dilation of the pancreatic duct
- Bile duct obstruction (causes include gallstones)
- Evaluating narrowed segments, also known as strictures, of the bile ducts
- Cancer in the liver, pancreas, or gallbladder
- Infections of the bile ducts
- Diagnosing conditions such as primary biliary cholangitis or primary sclerosing cholangitis
- A sample of tissue may also be removed (biopsy) during the ERCP to be sent to the lab for further analysis by a pathologist
Therapeutic purposes
ERCPs may be used to treat certain conditions of the bile ducts and pancreatic ducts. It may also be used before, and after gallbladder surgery to help improve the ease of the overall surgery. Certain conditions ERCP can treat include:
- Gallstone extraction
- Insertion of a stent to relieve blockage
- Dilation of strictures
- Endoscopic sphincterotomy (opening up the entry of the ducts into the bowel)
- Drain blocked areas
Dr Benjamin Yip shares, “Although ERCP is one of the higher risk endoscopic procedures, it is usually well-tolerated. I had a patient in her 90's with incurable ampullary cancer which I did ERCP and inserted a biliary metal stent to prevent biliary blockage. I remember seeing her one year after the ERCP and she remained well and the stent was functioning well!”
Is an ERCP considered surgery?
An endoscopic retrograde cholangiopancreatography is considered a minimally invasive procedure. There is minimal damage to body tissue.
Can an ERCP remove gallstones?
An ERCP can extract gallstones from the bile duct, but not from the gallbladder.
ERCP vs MRCP
Magnetic resonance cholangiopancreatography (MRCP) is an alternative to ERCP in terms of imaging the biliary tree and investigating the causes of biliary obstruction. The main difference between ERCP and MRCP is that while MRCP is a diagnostic procedure, it is not a therapeutic procedure. This is in contrast to ERCP, which is used for both diagnosis and treatment. MRCP is thus used more with a diagnostic point of view while ERCP is more often used for therapeutic purposes. Nonetheless, both procedures are very helpful in managing patients.
Procedure wise, MRCP requires the patient to lie down still within an MRI machine located outside of the body for several minutes at a time. The MRI machine will then generate a magnetic field around the patient to produce images of the biliary tract which can aid in diagnosis. Patients do not feel anything while the scan takes place, and the procedure takes less than 20 minutes. No contrast is used.
ERCP, on the other hand, consists of inserting an endoscope into the mouth of the patient all the way up until the pancreas. The gastrointestinal tract is visualised with the video camera on the endoscope. Contrast is also used together with x-ray imaging.
How do I prepare for an ERCP?
- Before going for ERCP, inform your care team about any allergies or medical conditions that you have, as well as your detailed medication list and whether or not you are pregnant.
- Generally, you will be asked to fast at least 8 hours before your procedure.
- Make plans to have someone drive you home after the procedure as driving is discouraged within 24 hours of ERCP as the effects of the sedation given can persist for several hours after the procedure.
What can I expect from the ERCP procedure?
The ERCP procedure usually takes between 1-2 hours. Patients who undergo the procedure will usually have an intravenous plug set onto their arm to help in the administration of sedatives and other medication. A liquid anaesthetic will also be given to numb the throat and prevent gagging. A mouthguard might also be employed to facilitate the entry of the endoscope. The procedure is done lying on the left or on the stomach face-down.
After sedation, an endoscope is entered through the mouth, down the oesophagus, into the stomach, and lastly, into the duodenum. Once the endoscope reaches the papilla (opening of the bile duct into the duodenum), a thin, flexible guidewire is pushed through the endoscope and into the duct.
A special dye is then injected into the bile duct and pancreatic ducts to make the ducts more visible on x-ray. A type of x-ray imaging, called fluoroscopy, is then employed to examine the ducts and to check for any blockages, narrowed areas, or masses.
If the ERCP is done for therapeutic purposes, the doctor may pass small tools through the endoscope to help in the treatment. The tools employed can help carry out numerous functions, including removing stones, taking a biopsy, opening up narrowed segments, and stent insertion.
Post-ERCP
After the ERCP, you will be brought to a recovery room to rest for 1-2 hours to wait for the sedation and anaesthesia to wear off. Most patients would be required to stay overnight in the hospital.
Common side effects include bloating, nausea, and sore throat post-ERCP. However, these should subside within a few days. Overall, the discomfort from ERCP should be mild, and patients might have little memory of the test because of the sedation given.
Some warning symptoms include:
- Severe abdominal pain
- Bleeding from the rectum
- Black stools
- Fever
- Nausea or vomiting that does not subside within a few days
Seek medical attention immediately if you experience any of these symptoms.
Summary
Overall, ERCP is a safe procedure that allows for both diagnosis and therapeutic treatment for various abdominal conditions. It is a safe alternative to surgery, and it allows for a wide breadth of medical care and treatment.
References
- ASGE | Understanding ERCP, https://www.asge.org/home/for-patients/patient-information/understanding-ercp. Accessed 10 May 2022.
- “Endoscopic Retrograde Cholangiopancreatography (ERCP).” Johns Hopkins Medicine, https://www.hopkinsmedicine.org/health/treatment-tests-and-therapies/endoscopic-retrograde-cholangiopancreatography-ercp. Accessed 10 May 2022.
- “Endoscopic Retrograde Cholangiopancreatography (ERCP) | NIDDK.” National Institute of Diabetes and Digestive and Kidney Diseases, https://www.niddk.nih.gov/health-information/diagnostic-tests/endoscopic-retrograde-cholangiopancreatography. Accessed 10 May 2022.
