Gastrointestinal Resection and Anastomosis in Cats

Overview of Feline Gastrointestinal Resection and Anastomosis

Gastrointestinal resection and anastomosis, commonly referred to as an R & A, is a surgical procedure in which a section of the cat’s esophagus, stomach and/or intestinal tract is removed and the remaining parts are connected. This procedure may be performed at any point along the gastrointestinal tract from the esophagus to rectum, and the section removed can vary in length from a few centimeters to very long lengths.

What are Indications for a GI Resection and Anastomosis for a Cat?

Reasons for doing this procedure include:

Foreign body such as ingested toys or string or other obstruction
Perforation of the intestine
Intussusception in which one piece of intestine becomes incorporated in an adjacent segment
Torsion or twisting of the stomach or intestines
Neoplasia (cancer)

Animals with these problems may display gastrointestinal symptoms such as vomiting, decreased appetite, weight loss, and/or diarrhea.

Resection and anastomosis is a commonly performed procedure. The success rate is relatively high, but depends on the underlying disease process and region of the gastrointestinal tract that is removed. The surgery can have serious complications if the affected animal does not heal well and the anastomosis comes apart or if a large majority of the intestinal tract is removed.

Diagnosis of Problems Leading to a GI Resection and Anastomosis for Cats

In general, the decision to perform a resection and anastomosis of the gastrointestinal tract is made by the surgeon during exploratory surgery.
Special tests may be necessary to help determine whether surgery is necessary or not. Such tests include radiographs (with and without contrast material), abdominal ultrasonography, and abdominocentesis, or the removal of a sample of fluid from the abdominal cavity with a needle.

Treatment with a Gastrointestinal Resection and Anastomosis in Cats

Home Care

Your cat will often be kept in the hospital for a few days for continued treatment and monitoring after a gastrointestinal resection and anastomosis has been performed. Once your cat is discharged from the hospital you will need to restrict his/her activity for several weeks. You will also need to monitor the skin incision for redness, swelling, or discharge.

Your cat may be sent home on a diet restricted in either volume or type of food fed and/or medications. Your veterinarian will typically ask you to return for a recheck appointment in two weeks so that he/she can monitor your cat’s progress and remove the skin sutures.

Information In-Depth

Gastrointestinal resection and anastomosis is the name given to any surgical procedure in which a portion of the gastrointestinal tract is excised (resected) and the remaining ends of the tract are reattached (anastomosis).

Resection and anastomosis is most frequently done in the small intestines; however, resection and anastomosis of the stomach, colon (large intestines), or rectum is necessary with some diseases. Resection of a portion of the esophagus is less commonly performed.

Ingestion of a foreign body that subsequently becomes lodged in the small intestine is a common condition of cats that requires resection and anastomosis. The obstruction can lead to necrosis or death of the wall of the intestine and ultimately to intestinal perforation. The entire length of damaged intestine is removed such that the two ends of the reattached intestine are healthy.

Another cause of obstruction is stricture, in which the walls of the esophagus or intestine constrict like a tightening ring, limiting the size of the lumen or opening. Stricture can be the result of previous injury by foreign objects, previous surgery, or tumors.

Intussusception is a condition in which a portion of the gastrointestinal tract advances into the intestine adjacent to it, similar to an old-fashioned telescope. If the intussusception cannot be undone, resection and anastomosis of the affected intestine may be necessary.

Mesenteric (intestinal) torsion is the twisting of the small intestines on its blood supply. This condition is almost always fatal; however, occasionally when surgery is done quickly a portion of the intestine may be salvageable. The necrotic (unhealthy) portion is removed and an anastomosis is performed.

Neoplasia (cancer) or benign tumors can occur in any region of the gastrointestinal tract. Fortunately the esophagus, which is difficult to operate on and is most prone to complications after surgery, is rarely involved. The stomach, small intestines, large intestines and rectum do develop tumors that may require resection and anastomosis to treat. The rectum is the portion of the colon that passes through the pelvic canal to the anus. It is accessed through an incision near the anus or under the pelvis (the floor of the pelvis must be split to access this area of the rectum).

Tumors of the stomach, small intestine and large intestine within the abdominal cavity are approached through an incision in the animal’s belly. Large tumors of the stomach can be difficult to remove with “clean” margins (lack of tumor cells at the cut edge of the removed tissue). The small and large intestine are much longer and usually allow for several centimeters of unaffected tissue to be excised to maximize the chance for complete tumor removal.

Prognosis

Depending on the underlying condition that requires that resection and anastomosis be performed, the prognosis is variable. For benign conditions (such as foreign body obstruction, intussusception, and benign tumors) the prognosis is generally excellent. If perforation of the gastrointestinal tract has occurred due to any cause the abdominal contents are usually inflamed (peritonitis) and anastomoses may not heal well. Thus, the presence of abdominal infection generally warrants a guarded prognosis. If the blood supply to a region of the gastrointestinal tract has been compromised, such as with torsion, the patient must be monitored closely after surgery because healing may be impaired. Some neoplastic conditions carry a poor prognosis because of possible recurrence, while others may be cured with surgery.

Post-op Complications for Cats After GI Resection and Anastomosis

Any gastrointestinal resection and anastomosis procedure can be associated with post-operative complications. The most common and serious complication is leakage at the anastomosis site. Leakage can be secondary to poor surgical technique, but is usually the result of dehiscence, or splitting open, because the edges of the reattached tract were not completely healthy and did not heal well. This complication usually occurs within the first 3 to 5 days after surgery. If dehiscence occurs, gastrointestinal contents leak into the abdomen and cause infection. This requires another emergency surgery or euthanasia.
Another serious post-operative complication is stricture at the anastomosis site. As the anastomosis heals the scar tissue can form a constrictive band around the repair. If this occurs, the opening between the reattached segments becomes too small for food and digested material to pass through. This is an unlikely occurrence after small intestinal resection and anastomosis, but is more likely after esophageal surgery.
A less common complication is “short bowel syndrome,” which is the result of a majority of the small intestine being removed. The small intestines are important in absorption of nutrients from ingested food. As the ingested material moves too rapidly through the excessively short gastrointestinal tract, diarrhea and malnutrition occur. Sometimes these animals adapt over time and dietary changes may be helpful.

Diagnosis In-Depth

Resection and anastomosis is a technique that is usually determined to be necessary only after the surgeon has had an opportunity to assess the extent and nature of the disease process affecting the gastrointestinal tract. That assessment is usually based on direct visualization and palpation of the affected tissues during an exploratory surgery. Tumors of the rectum may be assessed before surgery with digital rectal examination.
Tests performed before surgery may suggest that a resection and anastomosis will be needed, and may help in determining that exploratory surgery should be performed. Complete physical examination is extremely important in any patient with symptoms related to the gastrointestinal tract (vomiting, diarrhea, poor appetite, weight loss). Thorough palpation of your pet’s abdomen by your veterinarian may reveal fluid build-up in the abdominal cavity, pain, or tumors.

Radiographs (X-rays) of the chest and abdomen may reveal a foreign object within the gastrointestinal tract and may show fluid or gas in the chest or abdomen. Occasionally, your cat is fed a contrast material that helps to outline the gastrointestinal tract before additional radiographs are taken. This can help to define strictures, intussusceptions, tumors and foreign objects.
Ultrasound examination is a useful tool for non-invasively examining the abdominal organs. It is also helpful in retrieving samples of fluid from the abdominal cavity (abdominocentesis) when only a small amount may be present, and in diagnosing intussusception.
The fluid obtained by abdominocentesis is examined under the microscope to look for the presence of bacteria or food material that would indicate that a perforation of the gastrointestinal tract has occurred.

Treatment In-depth

Gastrointestinal resection and anastomosis can be performed by hand suturing the two ends of the gastrointestinal tract back together or specialized stapling equipment can be used. The use of stapling equipment can greatly reduce the surgery and anesthesia time, but it may increase the cost.
The removed portion of the gastrointestinal tract is submitted to a laboratory for histopathological examination (biopsy).Culture of the fluid from the abdominal cavity may be performed to determine an appropriate antibiotic to treat peritonitis.

Home Care In-depth

Your cat is usually kept in the hospital for 1 to 2 days after surgery in order to continue intravenous fluid therapy and to allow antibiotics and pain medications (analgesics) to be administered. Your cat will be closely monitored during this time for evidence of infection or other complications.

Food and water may be withheld from your cat for the first 12 to 24 hours after surgery. If your cat does not vomit after drinking small volumes of water, small amounts of a bland diet can be offered. Once your pet is eating and drinking without vomiting, he may be discharged from the hospital.

Recovery after Gastrointestinal Resection and Anastomosis

Once your cat has been discharged from the hospital he must be kept quiet to promote healing. Restrict your pet’s activity for at least two weeks after abdominal surgery. Keep your cat confined to a carrier, crate, or small room whenever he cannot be supervised. Do not allow your cat to play or rough-house even if he appears to be feeling well.

Special instructions may be given for gradually increasing the volume of your cat’s food or for feeding a certain type of food. If your pet is not continuing to improve each day, or begins vomiting or refusing to eat again, contact your veterinarian immediately.If a culture sample was taken, the specific type of antibiotic that your pet was originally sent home with may need to be changed based upon those results. Antibiotics may lead to decreased appetite or diarrhea. Contact your veterinarian if you note any problems.The skin incision needs to be monitored daily for signs of excessive swelling or discharge, which may indicate problems with healing or even infection. Contact your veterinarian if you note any abnormalities.If the resection and anastomosis was performed because of a tumor, the biopsy report will indicate whether the tumor was benign or malignant and if it was completely removed, or not. Your veterinarian will make additional recommendations based on these results and may refer you to a veterinary oncologist for further treatment.