Article Written by Dr. Daniel A. Degner, Board-certified Veterinary Surgeon (DACVS)

Key Points

Kidney transplantation can make a world of difference in the quality of life for your feline family member

Transplantation can also extend the duration of life

Earlier transplantation leads to longer survival times

Acceptable candidates for transplantation

Your cat should be free of a variety of diseases other than kidney disease. These include:

• bladder or kidney infection
• thyroid disease
• cancer
• feline leukemia virus infection
• feline immunodeficiency virus infection
• chronic upper respiratory infection
• inflammatory bowel disease
• some types of kidney stones
• diabetes mellitus
• heart disease
• high blood pressure

Any of these diseases may complicate the potential outcome of the kidney transplantation. In addition, an ideal candidate for the surgery should not have lost more than about 20 to 25 % body weight. I have performed transplantation in spite of 40% loss of body weight with success. The recipient cat should also be type A blood, as it is very difficult to find a type B or AB donor. Blood testing, urine testing, ultrasound and x-rays will be performed on your pet to rule out these complicating diseases.

Questions that you need to answer for the transplant team are listed here

Acceptable kidney donor

Only living donors are used for kidney transplantation. These donors should be adult, healthy, large (preferably 10 pounds in weight), and no older than 5 years of age. A variety of testing is done on the donor cat to ensure its health and compatibility with the recipient cat. According to a research study, removal of one kidney from a donor cat does not increase the risk of developing kidney failure, nor does it shorten the life span of the cat. The donor must be adopted by you or a dependable family; the donor has given life so you must likewise give the donor a wonderful life.

Transplant patient preparation for surgery

It is common for cats in kidney failure to be anemic prior to the surgery. Administration of medication (erythropoietin) may be required for about 3 to 4 weeks prior to transplantation in order to reverse your pet’s anemia. If your cat is not eating well, we recommend that a stomach tube (PEG tube) be placed so that your pet will be in a positive nitrogen balance at the time of the surgery. About 2 days prior to the transplantation procedure, the recipient cat is given anti-rejection medication. Your pet will need this medication (cyclosporin) for the remainder of its life to prevent rejection of the transplanted kidney.

Transplantation surgery

Both the recipient and donor cats are on operated at the same time. One kidney is removed from the donor and implanted into the abdomen of the recipient. The ureter (tube through which the urine is passed to the bladder) is implanted into the bladder. If your cat does not have a PEG tube, it will be placed at this time.

Expectations be after the surgery

Typically, the BUN and Creatinine (poisons that are excreted by the kidney) will return to the normal range in 2 to 7 days. By 7 to 10 days after the surgery, your cat should regain its appetite and resume relatively normal grooming behavior. Over the next couple of months, your cat will gain weight and the anemia should resolve.

Transplantation does improve the longevity and quality of life of the patient. This procedure, however, is not a cure, as rejection of the transplanted kidney will occur. Acute rejection in the cat is rare, however, chronic rejection is common. Chronic rejection takes months to years to take place. Our expectation is that your cat will be able to live for another 2 years. There are cats that have surpassed this (6 or more years). When rejection does occur, it is possible that retransplantation can be performed.

Potential complications

Cyclosporin will suppress your pet’s immune system and make him/her more susceptible to infection. The most common complication is a bladder infection. The infection may also develop in the transplanted kidney. This type of infection may not clear up and the kidney may need to be removed. Stricture of the ureter of the new kidney can occur and results in obstruction to urine flow from the kidney. If this has not occurred by the 21^st day after surgery it is unlikely to occur. The vessels of the kidney can develop a blood clot and cause death of the kidney. By the third day after the surgery, the chance of this complication is minimal. In general we have a 95% success rate with microvascular surgery. Rejection of the kidney is also a potential complication, especially if the level of cyclosporin drops too low in the blood.

Aftercare

Your pet will need to be on anti-rejection medication for the rest of its life. Cyclosporin is not predictably absorbed from the intestinal tract and there is tremendous variation in the blood levels from cat to cat. It is, therefore, important to determine the amount of medication that your cat is absorbing via blood testing. The oral dose is then adjusted accordingly. For the first three months after the surgery, your pet should return weekly to us or your regular veterinarian for this testing. In addition, blood and urine tests will be done to evaluate the function of the transplanted kidney.

After the third month following transplantation, you will need to return for a recheck every month. It is imperative that you watch your cat closely for any signs of illness and seek immediate attention by your regular veterinarian or an MVS veterinarian who is familiar with kidney transplantation.

Finances?

Transplantation requires a significant financial commitment not only for the surgery and peri-operative care, but also after your pet is at home.

Frequently Asked Questions After Surgery - General Information

When should my cat have the first bowel movement after surgery?

• Many cats will not have a bowel movement for the first 4 to 5 days after surgery
• Reasons that a cat will not have regular bowel movements after surgery include:
  • The cat has been fasted prior to surgery
  • Cats do not eat well during the hospital stay
  • They frequently do not eat well when the go home
  • They are fed highly digestible food that produces little stool
  • Pain medication that contain narcotics (such as fentanyl patches, tramadol, morphine) can be constipating
• If a pet does not have a bowel movement on the 5th day of being home a stool softener such as metamucil can be fed
  • Dose of metamucil 1/4 tsp per mixed in with each meal (canned cat food)

My cat had surgery and will not eat.  What can be done?

• Offer smelly foods that contain fish such as tuna or smelly cat foods
• Try Gerber strained meats for babies such as the chicken, beef, turkey or veal
• Hand feeding;  place a small amount of food in the mouth so that they get the flavor
• Warm the food slightly in a microwave as the food will be more aromatic; remember to stir the food before feeding and test the temperature with your finger; it should  be only luke-warm.
• Some cats will only eat dry food, try kibble if your cat normally has been fed that food
• Petting and stroking your cat frequently will help to stimulate appetite
• Remember that most pets will not eat the first day or two after they get home from surgery
• Appetite stimulants such as cyproheptadine may be helpful
• If your cat refuses to eat anything for 7 days a stomach tube should be placed to provide nutrition so that a serious liver problem (hepatic lipidosis) does not develop

My cat is vomiting now that he/she is at home.  What can be done?

• The first thing for you to discern is whether your pet is vomiting or regurgitating.  Both will result in fluid or food being brought up.  Vomiting always will have heaving or retching of the abdomen prior to expulsion of the vomitus.  Regurgitation is not associated with heaving and the cat usually just opens the mouth and fluid or food will be expelled.  Usually the regurgitant will be clear or brown colored fluid. 
• Next is to identify the cause of the vomiting or regurgitation.
• Causes and treatment of vomiting after surgery
  • When some pets return home after a stay in the hospital they may drink excessive amounts of water at one time and then vomit; if this appears to be happening the water should be limited to frequent smaller amounts.
  • Medications such as antibiotics are a common cause of vomiting after surgery.  In order to see which medication is causing the problem the administration of each drug should be separated 2 hours apart.  Usually the pet will vomit or appear nauseated (drooling and sick look) within 1 hour of administration of the medication that they are sensitive to.  The antibiotic in some cases may be changed to a different one, or may be discontinued. 
  • Stomach upset from anesthesia is a potential cause of vomiting and will pass within a couple of days. 
  • Unusual cause of vomiting after surgery is internal organ failure.  Blood testing will confirm this problem. For this reason vomiting should not be ignored if it persists for more than 24 hours.
  • If your pet had surgery of the bowels or stomach, vomiting is always a concern, as it may indicate that infection of the abdominal cavity, called peritonitis, is present.  Do not ignore this sign.
  • Symptomatic treatment of vomiting involves with holding food for 12 to 24 hours, then introducing small amounts of bland food such as rice and lean cooked hamburger, if your pet does not vomit after that then.  In order to decrease the acidity of the stomach Pepcid AC 0.5 mg/kg given by mouth twice daily for 5 days can sooth an upset stomach.  Metoclopramide is a good anti-vomiting medication for cats.  You should always consult a veterinary healthcare professional before administering medication.
• Causes and treatment of regurgitation after surgery
• The most common cause of regurgitation is reflux of acid from the stomach into the esophagus while your pet is under anesthesia.  Acidic fluid from the stomach can cause a chemical burn of the esophagus and result in a bad case of heart burn, which is called esophagitis.  This results in poor motility of the esophagus so water and food will accumulate in this structure.  In most cases esphagitis is self-eliminating and will resolve within two or three days. 
• Regurgitation also can be caused by a neuromuscular degeneration of the esophagus and this problem will persist.  It is not associated with surgery, rather other underlying diseases.
• If the esophagitis is severe the esophagus may develop one or more strictures.  A stricture is a narrowing or stenosis of the esophagus, does not allow passage of food down the esophagus, thus the pet has persistent regurgitation.  This problem should be brought to the attention of your doctor within the first two weeks so that it can be treated by ballooning the stricture (minimally invasive procedure as it is done with the aide of an endoscope).  If an esophageal stricture is chronic surgery is needed.
• Symptomatic treatment of regurgitation caused by esophagitis includes feeding bland food, and administering a coating agent such as sucralfate.  You should consult a veterinary health care professional if the regurgitation continues for more than a couple of days.

How do I know that my cat is in pain following surgery?

• Pain is more difficult to assess in cats versus dogs as signs can be more subtle and they usually do not vocalize
• Signs of pain in a cat include the following:
  • biting if you get near the surgical site
  • growling or deep cry
  • not wanting to eat
  • hiding and not wanting to be near owner (remember that this could also be caused by the cat just being upset about leaving home and coming back)

What can be done for pain at home for my cat?

• Pain medication such as buprenorphine or a Duragesic (fentanyl) patch
• Tylenol will kill a cat as they lack abundant glutathione enzyme in the liver
• Anti-inflammatories can be used, but the dose is much less than dogs and they should be given only for a few days

Is it okay for my cat to lick or scratch the incision?

• If a cat licks the incision it will actually delay the healing process because they usually lick too much and traumatize the area.
• Cats have a barbed tongue, therefore a lot of damage can be done in a short period of time
• Licking can remove stitches and cause the incision to open
• Licking can become a severe habit that is difficult to break
• Licking can cause infection as the mouth has many bacteria
• Cats will frequently lick the incision when the owner is not watching such as at night time; if the skin looks red or excoriated the most common cause is from licking.
• To stop your pet from licking/scrtaching the following can be tried:
  • Elizabethan collar can be placed on the neck; this will not help stop your pet from scratching at the region
  • Cervical collar (bite not collar) is a less awkward device and can be effective at stopping a pet from licking the surgical site
  • If the incision is over the chest an infant tee shirt can be put on your pet and the waist of the shirt fastened in place with an ace bandage or duct tape.
  • If the incision is over the paw or lower limb a bandage or sock could be put on and kept up with tape.
  • Bitter apple can be applied around the incision; many dogs will continue to lick  after application of this topical
  • Bitter Apple and Liquid Heet^TM (obtain this from a drugstore...it is used for sore muscles) mixed in a 2:1 ratio can be applied around the skin incision
  • Antipsychotic medication in some cases is needed

Board-certification by the American College of Veterinary Surgeons

What does it mean?

• Four years of advanced training in surgery beyond the Doctor of Veterinary Medicine Degree

• Experience in the development of new surgical treatments

• Rigorous examination by the American College of Veterinary Surgeons to ensure competency in advanced surgical techniques

• Assurance that a veterinarian is a surgical specialist