ERCP is an endoscopic/telescopic procedure that allows access to the bile duct, which is the duct that drains bile from the liver to the duodenum (the first part of the small bowel), and to the pancreatic duct.
Before ERCP was developed, access to these structures would require surgery, and, in that era, that would have been open rather than laparoscopic/keyhole surgery.
Once the endoscopist has passed a wire up the duct, he/she can inject contrast and take an Xray, and can open up the bottom of the duct with diathermy and then pass other instruments up the duct (for example, an extraction balloon).
ERCP is used in various clinical settings and some examples are given below:
- To remove a stone from the bile duct. This link will take you to an excellent animation and video from NEJMvideo (New England Journal of Medicine), and it demonstrates very well the technique of ERCP in general and specifically of removing a stone from the bile duct.
- To place a stent in the bile duct to overcome obstruction. This could be a benign obstruction (for example, due to a stone in the duct) or a malignant obstruction (due to cancer of the pancreas or of the bile duct itself). Stents placed for benign disease are generally plastic and are removable, whereas permanent metal/mesh stents are used in cases of inoperable malignant obstruction. There are now some removable metal stents available, and this link will take you to one manufacturer’s webpage on this topic.
- To access the pancreatic duct – this is a less common indication, but there are some occasions when this is necessary.
Although it is a “telescope test”, ERCP does have the potential for complications. Some of these are listed below:
- ERCP is not always successful in that it is not always possible to gain access to the bile duct at the first attempt, and a second or subsequent procedure may be necessary.
- Bleeding can occur from the diathermy cut made to open up the bile duct, although bleeding that requires surgical or radiological intervention is rare.
- Pancreatitis can occur, and is more common if Xray contrast is injected into the pancreatic duct .
- Discomfort and bloating from air that is passed in to the duodenum to maintain the endoscopic view.
- Adverse drug reactions to anaesthetic agents, or to antibiotics.
- Perforation is very rare.
Most ERCP procedures are performed as daycase surgery, but some patients do need to stay overnight.