Biliary Interventions
Extrahepatic biliary obstructions present a great dilemma as they induce life-threatening metabolic derangements, causing excessive morbidity and mortality. Surgical treatment is often indicated, but the outcome with biliary re-routing surgery holds such a high risk, with the mortality rate ranging from 25-70% in dogs and over 75% in cats. If the metabolic derangements can be relieved by a fast and effective decompressive procedure than future surgical interventions for a more definitive fixation may be safer for the patient. We will discuss two options that can be performed in veterinary patients 1) endoscopic drainage through the common bile duct (ERCP) and 2) laparoscopic assisted biliary drainage by cholecystostomy tube placement.
Endoscopic Retrograde Cholangiopancreatotgraphy (ERCP) and Biliary Stent Placement
Endoscopic retrograde cholangiopancreatography (ERCP) is an IE technique used for the diagnosis, and potential treatment, of biliary tract disease, pancreatitis, or pancreatic obstructive lesions. To date biliary stents have been successfully placed in a small handful of normal purpose-bred dogs, and clinical investigation is underway. Using a side-viewed duodenoscope the major duodenal papilla is visualized and cannulated with a sphinctertome catheter. Once a retrograde cholangiogram and pancreatogram are performed a guidewire is advanced into the common bile duct under fluoroscopic guidance. Then, through the endoscope, a polyurethrane stent is advanced over the wire. With fluoroscopic and endoscopic guidance the stent is advanced into the common bile duct, transverses the major duodenal papilla and exits into the duodenum. This can be left in place until the obstructive lesion resolves (ie pancreatitis), or a permanent metallic stent can be used in the case of neoplasia. This bypasses the need for re-routing biliary surgery for EHBDO.
Laparoscopic Cholecystostomy Tubes
Laparoscopic cholecystotomy tubes have been reported in a small number of clinical veterinary patients. They can be accomplished with very short anesthesia times. An 8 or 10 french locking loop pig-tail catheter can be advanced through a right paracostal approach being visualized with laparoscopy. With transhepatic penetration with the catheter, the gallbladder is accessed. Once the trocar is into the lumen of the gallbladder, as visualized via laparoscopy, the trocar and stylette are slowly removed and the locking loop mechanism is set in place. The catheter can drain the gallbladder and can be sutured securely to the body wall. This can remain in place until the patient is a better anesthetic candidate for surgery, or for 4—6 weeks while a seal is achieved and a more benign lesion resolves (pancreatitis), bypassing the need for surgical intervention.