In a healthy cat, bile made in the liver flows through the gallbladder, to the common bile duct, and into the intestines. When the common bile duct becomes constricted, blocked or swollen shut, sometimes an emergency surgical procedure called a “Cholecystoduodenostomy” may be recommended. In this procedure, a hole is created in both the gallbladder and the intestine and the two organs are attached so that bile can bypass the common bile duct altogether. This procedure must be performed by an ACVS board-certified veterinary surgeon. 

The surgery is very risky, in part due to the fact that most cats needing it have already presented with severe anorexia and vomiting. In some, the first indication that something is wrong with the bile duct is an elevated level of bilirubin on a blood test. An ultrasound may also reveal a thickened gallbladder or a visual blockage. If the gallbladder is deemed healthy, establishing a new permanent duct may be the best course of action. 

To prepare the cat for surgery, full blood work will need to be run to determine if the animal is a good candidate for general anesthesia. An ultrasound, CT scan or MRI can be useful in judging whether a duct drainage or duodenum anastomosis is possible, as these procedures carry less risks. If the veterinary surgeon deems the cat well enough for surgery, a date for the procedure will be booked. 

This operation is often performed using an endoscopic gastrointestinal anastomosis stapler, which is a precise tool that allows easy maneuvering in small spaces. It also results in the least amount of wound leakage, as it seals off tissue as it cuts. An incision to the abdomen will be made, and the gallbladder will be loosened from the surrounding liver tissue to lessen tension. A stoma (hole) anywhere from 2.5 to 4 cm will be made in both the gallbladder and the duodenum. A simple suture pattern is then used to fully attach these two organs, with extra care being used at either end of the stoma to ensure the area is fully sealed. The gallbladder may need to be drained via needle aspiration or by using suction. After this has been done the abdominal opening can be closed and either sutured or stapled. 

A cholecystoduodenostomy carries a survival rate of around 50%. It the cat is able to survive the procedure and the two weeks of healing that follow, the success rate of the surgery is high. If the stomas heal together, a new, permanent duct is created which completely bypasses the common bile duct. It has been noted that larger stomas function better than smaller stomas, so a 4 cm opening should be aimed for if possible. Suture administration also has a large impact on surgery success, and as such techniques should be chosen and delivered carefully. 

There are two other procedures that provide a similar bypass for bile flow which should be considered. A common duct drain tube may be inserted from before the obstruction to the duodenum, which can be easier to heal from. A common bile duct duodenum anastomosis is another option, where a stoma is created in the common bile duct and then directly attached to a corresponding stoma in the intestine. Both of these procedures should be pursued if possible before a cholecystoduodenostomy, as they carry lower rates of mortality. The procedures themselves are more complex, and a specialized surgeon may be needed to perform them.

The first two to three days after the procedure are the most crucial in the healing process. If the cat survives this period, a full recovery is likely. Vomiting after surgery may be a sign of serious complications such as peritonitis, organ failure, a bad reaction to the anesthetic or evidence of a stoma that was made too small. Bowel movements should resume normally after 5 days. The cat will likely need to be coaxed to eat, using warm, aromatic foods and hand feeding them to the animal. Appetite stimulants may need to be administered and a feeding tube will be inserted as a last resort if regular eating has not resumed in one week's time. 

Pain medication and antibiotics will be needed in the week that follows the surgery. A follow-up appointment will be scheduled two weeks after the day of surgery. Liver enzyme levels will remain high up to six months after the procedure, returning to normal in about one year. If cancer has been found, additional extensive treatments may be required. 

The average cost to have a cholecystoduodenostomy performed on a cat can range anywhere from $700 to $3,000 depending on the various diagnostic procedures that are done before the operation. Advanced imaging techniques including MRIs or CT scans can add an additional $1,000 to the total of treatment costs. Specialized surgeons may charge more than general veterinary surgeons, but offer expertise and can positively impact the rate of survival. If at all possible, a common duct drainage or duodenum anastomosis should be sought out before a cholecystoduodenostomy is chosen, as the price is similar and the mortality rates are lower. 

The short-term complications after a cholecystoduodenostomy pose great risks to the cat. The liver or entire abdominal cavity may become infected after surgery and leakages from improperly sealed stomas are not uncommon. Complications involving the comedown off of general anesthesia are the number one cause of death from this procedure. Respiratory arrest is also possible during surgery. If this procedure is deemed necessary, there is often no alternative that will lengthen survival. 

To prevent the need for your cat to have an emergency cholecystoduodenostomy, certain measures can be taken depending on the underlying cause of blockage to the common bile duct. To lessen the likelihood of pancreatitis, feeding your cat a diet low in carbohydrates made out of natural, species-appropriate ingredients can be effective. Digestive enzymes can also be effective to help to help the body break down food. Certain medications and steroid treatments such as potassium bromide and Prednisone should be avoided, as they can cause insulin levels to rise. 

To lower your cat's risk of cancer, avoiding known cancer causing agents can help. This includes limiting your cat's exposure to car exhaust, or by prohibiting smoking in the home. Eliminating cigarette smoke from your home will also be beneficial to all those living there. Certain types of cancer develop due to genetic predisposition, so learning about your cat's parents’ health can help prepare for such an event. Scarring of the common bile duct can be greatly prevented by keeping your cat indoors and away from moving vehicles. Use only specialized surgeons when having procedures performed on your pets.