Choledochotomy in Dogs

The common bile duct is a part in the body where bile from the liver and gallbladder drain to the intestines. The health of these organs affects many vital functions of the body including digestion, toxin management and hormone production. When something blocks or limits the drainage of the bile produced in the liver, serious illness often results. The most common causes for a common bile duct blockage in a dog are choledocholithiasis (gallstones) or bile duct sludge accumulation. 

In cases where a blockage is suspected or has been confirmed by blood work and ultrasounds, a veterinarian may recommend that the dog receive a choledochotomy, which is an exploratory surgery where an incision is made into the bile duct. As this surgical procedure carries many risks, it is not performed on an elective basis, but only in the event of an emergency. The goal of the surgery is to locate or remove obstructions, insert drainage tubes or close ruptures in the common bile duct. This operation should only be performed by an ACVS board-certified veterinary surgeon who has received at least four years of extra training in surgical procedures. 

To confirm that a choledochotomy is the right course of action, blood work will have to be performed to verify that the dog will be able to survive the administration of a general anesthetic. An ultrasound will be used to locate the area that has become blocked or has ruptured. A CT scan or MRI may be suggested if multiple blockages exist or if a cancerous tumor is suspected. Endoscopy may be used as a non-invasive way to collect more information about the issue, requiring only a small abdominal incision. At this point the veterinarian will decide if surgery is necessary. It is recommended in some instances for the surgery to be postponed up to ten days after the rupture or blockage has occurred, as some do heal on their own. 

The actual procedure will require an abdominal incision, followed by an incision to the common bile duct. A catheter may be inserted into the duct in attempt to flush out mucus buildup and stone obstructions. The gallbladder may need to be removed, which will be determined during surgery. Any ruptures will be sealed if possible. The most effective way to close an incision or rupture on the common bile duct is by using sutures combined with collagen biomaterials. The abdominal incision may be closed using either sutures or staples. 

As a choledochotomy is an exploratory surgery, success is guarded. When combined with a cholecystectomy (gallbladder removal), the surgery has a 33% chance of being successful. In instances where a cholecystectomy can be decided on before surgery, success rates jump up to 86%, as an incision no longer needs to be made to the bile duct. If the gallbladder is deemed healthy during the surgery, choledochol tubes may be placed to bypass any blockages in the common bile duct. In surgeries where blockages or ruptures are properly fixed, the results are permanent and recurrence is rare. 

The first two to three days post-surgery are the most critical in terms of healing. Any instances of vomiting should be taken seriously, as it may be an indication of organ failure, infection or complications from coming off of the anesthesia. Stool softener should be given to the dog, with bowel movements often taken 5 days or longer to resume. Extra measures may need to be taken to encourage the dog to eat, including making warm meals for the dog and hand feeding it. Pain medication will be administered to the animal. Excessive pain should dissipate after the third day of recovery. 

An Elizabethan or cervical collar should be put on the dog to prevent it from licking its incision and delaying the healing process. Bacterial infections are often found in cases of gallbladder mucoceles and will require a course of antibiotics to remove. A follow-up appointment will be needed one to two weeks after the operation to assess how the incision is healing. If cancer has been found in the dog, extensive treatment may commence. 

Depending on the extent of the diagnostic treatment that the dog receives and how much medication is required post-surgery, the cost of a choledochotomy may range from $1,500-$8,000. Having an endoscopic evaluation and advanced diagnostic imaging may bump costs up substantially, but provides more information to the vet for preparing the surgery. If at all possible, a cholecystectomy alone should be attempted, as this surgery poses less healing complications and costs the same amount. Supportive care alone may be chosen in instances where financial means are an issue. Even in cases of partial obstruction, these measures are generally unsuccessful. 

A choledochotomy is a procedure that carries with it many risks. Surgeries involving the liver, gallbladder or common bile duct tend to have more anesthesia complications. Incisions to the common bile duct are very difficult to properly seal, leading to the potential of bile leaking into the body which can cause serious symptoms and infection. This complication results in a high rate of failure in choledochotomies. If cancer is found in the dog, ongoing treatment involving more surgery is possible.

There is an association between certain breeds of dog and issues leading to the blockage of the common bile duct. Miniature schnauzers and poodles are prone to developing cholesterol or bilirubin stones which can obstruct the bile duct. These stones are present more often in older, female specimens. Cocker spaniels and Shetland sheepdogs are predisposed to develop gallbladder mucoceles, leading to sludge buildup in the common bile duct. Both cancerous and benign tumors in the gallbladder or bile duct are rare in dogs. 

To prevent stones or sludge from forming in your dog, there are certain supplements and activities that may be effective. Giving your dog Vitamin E may help the liver to function, in addition to providing a liver-friendly diet made from appropriate foods. The immune system can be strengthened with the use of Vitamin C. Milk Thistle has also been shown to assist the liver in metabolising food. In cases of gallbladder or common bile duct cancer, the best prevention is to avoid known cancer-causing carcinogens such as car exhaust and cigarette smoke, which are harmful to the owners of the dog as well. Keeping your dog on a lead during all outside walks can help prevent it from encountering serious bodily harm, resulting in ruptures to the common bile duct.