Decompressing and stenting obstructed biliary ducts. Ken U. Ekechukwu, MD, MPH, FACP.

What is biliary decompression and stenting?
The word biliary derives from the small tubes or canals in the liver called bile ducts that drain bile which the liver makes into the gallbladder and the intestine. These tubes branch out like a tree, with their main stem or trunk running out the liver through the head of the pancreas (the organ that makes insulin and which contributes its own duct to the main bile duct) to empty into the upper alimentary tract. These ducts, like similar tubular structures in the body, are prey to many diseases that narrow or obstruct them. The diseases may be systemic, like in autoimmune diseases, or local, like cancer of the ducts or the head of the pancreas. Such obstructions or narrowings (known in medical jargon as strictures or stenoses (singular, stenosis)) impair the drainage of bile from the liver, causing bile to spill into the blood stream and urine and turn the eyes, the skin, and the urine shades of yellow. (You probably have heard the word “jaundice”, which means yellowing of the white of the eye). In severe cases the deposition of bile salts in the skin causes generalized intense itching. In addition, the stagnant bile in the dilated ducts, like any stagnant body fluid, can become infected, setting up a serious blood infection that may claim life. Of course, the symptoms and signs of the primary illness contribute to the patient’s medley of symptoms and signs.

For these reasons physicians strive to relieve biliary obstructions when they happen. Such relief, or biliary decompression, may be done by a surgeon, a gastroenterologist, or an interventional radiologist depending on the nature, location, and severity of the obstructing disease. A surgeon will have to open the belly or use a laparoscope to cut out or bypass the disease; a gastroenterologist approaches the problem through the mouth, past the esophagus and the stomach to place a balloon or stent across the obstruction and dilate it; an interventional radiologist enters the ducts through a small skin cut in the side or front of the belly and passes a small tube, called a catheter into the dilated ducts for bile drainage. Sometimes the interventional radiologist’s catheter is insufficient for the patient’s needs due to the nature of the disease, like in advanced bile duct cancer or advanced cancer of the head of the pancreas requiring the interventional radiologist to dilate the narrowing or obstruction and place a stent across it. This is biliary stenting.

How do I prepare for biliary decompression and stenting?
First, you or a designee must ask for and receive from your care provider an account of the merits and demerits of this procedure and its alternatives. When you have done this, you must endorse the procedure by appending your signature on a document called a consent form. It is likely, if you require biliary decompression and stenting, that you are on admission in a hospital which takes the burden of preparation off you. You will need to have nothing by mouth starting the midnight of the day of your procedure to allow safe sedation for the procedure. Your health care provider will screen you for any impairments of your blood’s clotting ability and correct them to avoid serious hemorrhage. You will have to receive some antibiotic to prevent the bacteria that may have colonized the stagnant bile from seeding your blood and causing you serious infection. This is even more paramount and mandatory if you are already sick with blood infection.

How is biliary decompression and stenting done?
You will be brought to the interventional radiology suit on the morning of the procedure and be placed on the procedure table. Following aseptic preparation of the procedure field you will receive intravenous antibiotics and conscious sedation. The skin entry site will be numbed with a local anesthetic and a small skin cut made. Using fluoroscopy or ultrasound for guidance the interventional radiologist will pass a long skinny needle through the skin into the liver and, if subsequent contrast injection into the needle confirms that it is in a dilated duct, the access will be dilated so that a catheter can be advanced across the stricture or obstruction. It is common practice to delay stenting of the obstruction after decompression by several days, because it reduces the chance of seeding the blood stream with bacteria in the stagnant bile. If this staged process is adopted, you will return to the IR suite on another day and the established path used to place a stent across the obstruction. The catheter will then be removed in a few days and after your physician confirms that the stent is letting bile through.

What are the contraindications to biliary decompression and stenting?
Contraindications are conditions that make percutaneous biliary decompression risky. You must let your health care provider know of them before embarking on this procedure. They include:
• Uncorrectable coagulopathy (this means ‘thinning’ of your blood which will make you bleed too much). 
• No safe access to the biliary ducts.

How do I care for a biliary drainage catheter?
It is easy to care for the drainage catheter at home by yourself. You must avoid unintentionally pulling your catheter out; this often happens when people roll around in their sleep, when their caregivers move them around while attending them, or during ambulation when patients step on their drainage bag or tubing while in motion. Your interventional radiologist will see you at specified intervals at the clinic and check your blood electrolytes for any changes that may come from the daily loss of bile. It is good practice to change the catheter every 3 months to keep it from blocking. If, on the other hand, a stent has been placed there is no need for catheter change, but you will be periodically checked for rising bile levels in the blood, because the nature of some of the diseases that cause bile duct obstruction predicts future stent failure.