Patients presenting to the surgeon for management of jaundice as a presenting sign have a very specific group of conditions. This group of conditions centered around the hepato-biliary system, the proximal gastrointestinal system (stomach and duodenum), and the pancreas. Because of the complexity of managing cases with conditions involving this area we adopt a multi-disciplinary approach with several specialist team members; anaesthesia, internal medicine, surgery and diagnostic imaging.
Anatomy of the hepatobiliary system
Bile is produced by the liver and then drains through a series of tributaries; canaliculi into inter-lobular ducts, which unite to from the hepatic ducts (2-8 in dogs) from each lobe of the liver, draining into the bile duct, with bile collecting into the gall bladder via the cystic duct. The bile duct travels within the wall of the duodenum for 1-2cm. The bile duct empties into the duodenum at the major duodenal sphincter, which is located 1.5-6.0 cm distal to the pylorus.
Peri-operative management of hepatobiliary patient
The most common causes of extrahepatic biliary obstruction and therefore the most common comorbidities to consider when operating on a jaundiced patient include pancreatitis (inflammation of the pancreas), cholangitis/cholangiohepatitis (inflammation or infection of the biliary tree), neoplasia (cancer) and cholelithiasis (stones in the biliary system). Other less common comorbidities or causes that have been reported include diaphragmatic hernia causing gall bladder entrapment, migrating foreign body or parasitic infection.
An obstruction of the biliary system can result in profound systemic disease, including hypertension (low blood pressure), coagulopathy (bleeding abnormalities), reduced ability of heart to pump blood gastrointestinal ulceration and a delay in wound healing.
Patients are therefore carefully assessed for any changes in vital clinical parameters and stabilised accordingly prior to surgery. Assessment for coagulation abnormalities and pretreatment with fresh whole blood, fresh frozen plasma or Vitamin K may be prudent and should be considered.
Common surgical techniques for the hepatobiliary system
When to take a patient with an extrahepatic biliary obstruction and jaundice to surgery is a difficult decision.
Typically, we proceed to surgery if there is evidence of an obstruction to the bile ducts and/or worsening blood work suggestive of an obstruction.
The most common surgical procedures of hepatobiliary system are:
Cholecystectomy – removal of the gall bladder
Choledochotomy – opening of the common bile duct
Choledochal tube stenting – placement of a stent in the common bile duct
Cholecystoenterostomy – creation of permanent stoma between the gall bladder and the small intestine (typically duodenum or jejunum)
Deciding which procedure to perform relies on some clinical judgement, the pre-surgical imaging findings and clinical presentation. We try to answer the questions below to determine the most appropriate surgical procedure - this is a joint decision making process between the surgeon, internal medicine consultant and the diagnostic imaging specialist.
Can we demonstrate patency of the common bile duct by catheterization?
If patency of the common bile duct cannot be demonstrated by catheterisation a cholecystoenterostomy should be considered. Cholecystectomy is not indicated in this situation.
If we can catheterize the common bile duct, does the patient have clinical evidence of a functional obstruction (ie pancreatitis)?
Biliary stenting is an option for management of cases that have potentially reversible disease process (i.e feline triaditis/pancreatitis) or as a palliative procure for neoplastic processes.
Is the common bile duct intact or ruptured?
Following traumatic rupture of the common bile duct, the surgical repair site can be supported by placement of a choledochal stent.
Prognosis associated with surgery
Prognosis following surgery depends on the exact condition and procedure being performed. We will discuss the expected outcome and prognosis with you before we proceed with any intervention. Surgery should be considered as part of the entire management of the jaundiced patient. As such, we take a team approach and any discussion about management will involve several members of the team.