Biliary drainage

What is biliary drainage?

Biliary drainage is a procedure to unblock or bypass a blocked bile duct, letting bile flow out of your liver again, either into your bowel or into a bag outside your body. It's usually carried out by a specialist doctor called an interventional radiologist, using X-ray and ultrasound guidance rather than open surgery.

What conditions does it treat?

Biliary drainage treats a blockage or narrowing of the bile ducts, which stops bile draining properly from your liver into your bowel. This can be caused by a number of conditions, including:

• gallstones, either in the gallbladder or within the bile ducts themselves
• inflammation of the pancreas (pancreatitis) or of the bile ducts (sclerosing cholangitis)
• tumours of the pancreas, gallbladder, bile duct or liver
• enlarged lymph nodes near the pancreas or liver, often linked to cancer
• injury to the bile ducts during previous surgery
• infection, or scar tissue narrowing the ducts.

A blocked bile duct causes bile to back up into the liver, leading to jaundice (yellowing of the skin and eyes), along with itching, nausea, poor appetite, dark urine and pale stools.

What are the benefits of having biliary drainage?

The main benefit is relief from the symptoms caused by a blocked bile duct, such as jaundice, itching and nausea, and it can also improve how well your liver is working. Biliary drainage is sometimes needed as a preparation step before surgery or other procedures on the bile duct, such as removing a stone or tumour.

Are there different types of approaches?

The most common approach is percutaneous transhepatic biliary drainage, where a tube is passed through the skin and liver into the blocked duct, guided by ultrasound and X-ray. An alternative is endoscopic biliary drainage, where a doctor reaches the bile duct using an endoscope passed down through the mouth, sometimes after an endoscopic attempt (ERCP) hasn't been possible or hasn't worked. Drainage can be external, with bile draining into a bag outside your body, or internal, where a catheter or stent is placed across the blockage so bile flows into the bowel as normal. A permanent metal stent is often added a few days after the initial drainage to keep the duct open without needing an external tube, and sometimes a narrowed section of duct is widened with a balloon (dilatation) as part of the same treatment.

What happens before the procedure?

You'll usually have a blood test beforehand. It's important to tell your team about any blood-thinning or antiplatelet medicines, such as aspirin, clopidogrel or warfarin, as well as diabetes medicines like metformin or insulin, since these may need to be paused or adjusted. You'll be asked to stop eating for several hours beforehand, commonly around 4 to 6 hours depending on the hospital, though you can usually drink water up until about 2 hours before. Let your team know about any allergies, including to contrast dye or anaesthesia, and bring an up-to-date list of your medications. You'll have the chance to ask questions and discuss the procedure before signing a consent form, and you're free to decide against it afterwards if you're not comfortable going ahead. Most people are admitted as a day case, though it's worth packing an overnight bag in case a longer stay is needed.

What happens during the procedure?

The general steps of a percutaneous biliary drainage procedure are:

1. A cannula is placed in a vein in your arm so you can be given antibiotics, pain relief and sedation.
2. You lie on your back on the X-ray table, your skin is cleaned with antiseptic, and sterile drapes are placed over the area.
3. Local anaesthetic is injected into the skin and deeper tissue; this stings briefly before the area goes numb.
4. Using ultrasound and X-ray guidance, a thin needle is passed through the skin and liver into a bile duct, and contrast dye may be injected so the ducts show up clearly on X-ray.
5. A guidewire and catheter are passed into the duct, crossing the blockage where possible, and one end is brought out through the skin and connected to a drainage bag, secured with a dressing.
6. A permanent metal stent may also be placed across the blockage, either during this same procedure or at a later date.

What does recovery look like?

Afterwards, you're taken back to the ward, where your blood pressure, pulse, oxygen levels and temperature are checked regularly, and you'll rest in bed for a few hours. Most people go home the same day or the next, as this is usually done as a day case, though occasionally an overnight stay is needed. If you're discharged with an external drainage catheter and bag, a nurse will teach you how to look after it, including emptying the bag regularly, keeping the dressing clean and dry, and being careful not to catch or pull on the tube. You can usually get back to normal activities within about 24 hours, avoiding heavy lifting, swimming or soaking the area for the first couple of days. Your team will let you know when the catheter can be removed, which isn't painful, and you may need further X-rays or scans first to check the blockage has been relieved. Some people go on to have an internal stent fitted once drainage is established, allowing the external tube to come out.

What are the risks and complications?

• bleeding, which occasionally requires a blood transfusion or, rarely, a further procedure to stop it
• infection at the drain site, or, rarely, infection spreading into the bloodstream (septicaemia); antibiotics are usually given to help prevent this
• a bile leak around the catheter, sometimes forming a collection that needs further drainage
• the drain being unable to be placed, in which case surgery or a different procedure may be needed instead
• the catheter becoming twisted, blocked or accidentally pulled out
• a small dose of radiation from the X-ray imaging used, kept as low as reasonably possible
• with a stent specifically: early risks include infection, bleeding or pancreatitis, and later problems can include blockage from tissue growth or sludge, or the stent moving out of place.