Transhepatic Jaundice Interventions and ERCP

Indications
Biliary strictures
Malignant bile duct obstructions palliative and curative
Bile duct biopsies
Stone removal
Endoluminal therapies

Noninvasive Imaging
US with colour doppler
- limited by bowel gas if present.
CT, MR, MRCP

Principles
1. ERCP often preferred;
- especially if coagulopathies, ascites, large liver cysts
2. PTC may be preferred to define complex liver ductal anatomy, for reconstructions.
3. May need both to define ducts above and below an injury.
4. PTC is the first step to PBD
- and the only absolute contraindication is coagulopathy.
- e.g. platelets <100,000 or INR >1.5.
- also avoid in hepatic infxs.
- ascites: should avoid chance of persistent leak around the tube; big problem.

PTC/PBD
Advance needle into liver, under fluoroscopic guidance
- will see bile push back contrast, then flush and light up biliary anatomy.
Need to find a peripheral duct for a PBD catheter
Sometimes need to advance needle sub-xiphoid for left duct system access.
If pt is critically ill, placement of an external drainage catheter would be effective.
- once stable, could return for conversion to internal / external drainage / stent.
--> ultimate goal always to re-establish biliary-enteric circulation.
Loss of bile can lead to substantial electrolyte disturbances.
Biliary drainage catheters are generally flushed 1-2x day, especially if viscous bile or infected.
--> sterile forward flushing, taking care not to draw forcefully back into the syringe; else may drag GI bugs into the biliary circulation causing sepsis.
May need periodic changing over a guidewire.

PTC --> Internal Drainage

Palliative biarly stenting.
Allows rapid treatment and reduces cost compared with catheter placements.
Eithe rplastic or metal
- plastic are larger, require dilation; painful, theoretical risk of bleeding
- metal are smaller, but deploy larger so that more permanent; can't be changed.
Patency generally 6-12 months.
- covered devices may extend this.

Complications of PTC
Technical success is high and complications low (5=8%)
Major = hemobilia, haemorrhage, sepsis, biloma, peritonitis, pancreatitis, pleural effusions; rarely, death.
Cholangitis is brief, often during catheter manipulation.
- usual sepsis management here.
Hemobilia / haemorrage is from injury to major vessels; generally managed by repositioning or upsizing catheters
- arterial branch injury may need arteriography.
Pericatheter bile leakage may occur if luminal flow not free.
- occasionally ascites leaks around the tube; purse string suture may fix it.

Removal
Over the wire cholangiogram first.

ERCP
 
Decompression
Sometimes performed via the nose
- allows measurement of bile volume and allows cholangiograms
- but more loss of bile salts, water, electrolytes, digestive enzymes.
Plastic stents commonly used here due to low cost and ease of removal
- but migrate and occlude early, often last only 3-6m; get colonized with a biofilm.
- larger lumens = better.
Metal stents now covered to prevent tumour ingrowth; long patency
- but higher risk of migration and pancreatitis.

Use in Choledocholithiasis
ERCP should be therapeutic  and not diagnostic as less invasive tests area available.
Note that US is insensitive for choledocholithiasis; sensitivity just 50-60%.
- MRCP sensitivity >90%, but a little less when there are small stones <5mm or biliary sludge.
CBD stones are found in about 15% of symptomatic gallstone patients.
Success of ERCP is ~90% at extraction
- balloon dilation of sphincter causes pancreatitis and is not recommended.
- stone are removed by sphincterotomy and extraction using a basket
- can trawl duct with a balloon to remove small stones and sludge
- removed 1 at a time to reduce complications of duct damage and bleeding.

Complication rate
About 5-15% depending on who is doing it.
Pancreatitis is most common; 2-7%
- higher in SOO dysfunction, females, younger pts, recurrent attempts.
Bleeding and perforation serious but 1% or so.
- higher bleeding if coagulopathy (always should be checked), sphincterotomy, cholangitis

Malignant obstructions
Used here for both tissue sampling and palliation.
Most patients have inoperable lesions, many that are operable should go straight to surgery if bilirubin level allows it.
Palliation is best with stenting; less long term issues but better morbidity, mortality and stay.
Success rates are 95%
- lower for hilar lesions; may end up needing PTC

Benign obstructions
Structures; complex area and specialist territory.
Dilate the stricture, maintain patency of the duct, e.g. by stenting.
- plastic stents more common here as can be changed easily.
High success rate 90%, but only with stent use.

Post-surgical strictures
Lap chole responsible for 80%.
Endoscopic treatment of biliary structure has 75% success rate and 65% of these patent at 70months.
Sequential ERCPs, increased number and diameter of stents until complete removal at 12months is first line approach.

Chronic pancreatitis
Associated biliary stricture rate high.
Accounts for 10% of bile duct strictures.
Multiple plastic stents has high long term success rate and should be first line.

Primary Sclerosing Cholangitis
Stricture dilating and stenting; see notes.