Renal Therapies

Dialysis

At Chicago's Lincoln Park Zoo, a male gorilla was given hemodialysis to help an infection-like illness. Unfortunately, IV medications, blood transfusions, and the dialysis were not enough to improve the gorilla's status, and zoo officials had to euthanize the suffering primate.

Kidney Transplant

In Coomera, Australia, a female Siberian tiger named Jai at the Dreamworld theme park was found to be suffering from a kidney infection. Veterinarians decided to perform the world's first-ever kidney transplant on a tiger, however the ten-hour operation was not a success.

Cardiac Therapies

Karma, a five month old tiger, was rescued from a neglectful breeder only to be diagnosed with the heart disease Tetralogy of Fallot. This has four key features associated with it. There is a hole between the two ventricles, a septal defect, and many levels of obstruction from the right ventricle to the lungs, pulmonary stenosis. The aorta lies directly over the ventricle defect and the right ventricle develops thickened muscle. Because the aorta overrides the defect and there is pulmonary stenosis, blood from both ventricles is pumped into the body, resulting in oxygen-poor blood being pumped to the body. Though this problem has been corrected many times in babies, this is the first case of open heart surgery on a tiger.

Dr. Theresa W. Fossum, professor and chief of surgery in the Department of Small Animal Medicine and Surgery teamed with a pediatric cardiovascular surgeon in an effort to correct the tiger's serious heart condition. Before the surgery, Karma's blood type was matched to his mother's, whose blood was used for transfusion during the surgery. After the five hour surgery, Karma was placed in ICU on a ventilator. Unfortunately, hours after the surgery, Karma went into respiratory arrest and doctors were not able to revive him.

Stents

Subcutaneous emphysema occurs in birds when air sacs rupture and is commonly corrected in larger birds such as psittacines, amazon parrots, macaws, and cockatiels. Initially cutaneous taps with a hypodermic needle reduce the trapped air and release the pressure under the skin but they quickly close and the problem returns. Permanent treatment of chronic subcutaneous emphysema is with a Teflon stent. In the larger birds, the trapped air tends to rise to the dorsum of the neck and the loose skin in that area expands. The air is drained by implanting a stent at the base of the skull in the back of the bird where it cannot be reached.

The stent for birds is either 12.7 or 16 mm in diameter with eight holes for suture placement. The outer rim is 8 mm in diameter, allowing the skin to tuck under the edge and preventing closure over the implant while healing. This surgery is done under general anesthesia where Isofurane induction and intubation are used. The pre-autoclaved stent is prepared by placing four stainless steel wire lengths through the four pairs of pre-drilled holes in the flange. An incision is made through the skin just long enough for the stent to be slipped through and positioned under the skin with one set of holes straddling each end of the incision and one set of holes on each side of the incision. A twenty-two gauge hypodermic needle is used to retrieve the wire suture ends through the skin and the sutures are tied, both closing the incision and affixing the stent against the subcutaneous skin surface.

The stents are inert and the only problem post-surgery has been some clogging by mucous or congealed tissue. This is easily fixed by removal with a needle. No cases of infection have occurred and no antibiotics are used.

In one case, a cockatoo underwent this surgery after being thrown around in his cage during the 1989 San Francisco earthquake. Previously the bird had been treated with this problem by frequenting another veterinary practice and having the trapped air removed every thirty days for about 8 months.

Orthopedic Therapies

Prosthetic Limbs

Richard Nitsch and veterinary surgeon David Anderson teamed up to fit a variety of animals with prosthetic limbs. Nitsch, with twenty years of experience making prosthetic limbs for people, creates the prosthesis as Anderson amputates the damaged limb. Nitsch makes the custom-fitted plastic and fiberglass limbs using the same molding and fitting process he uses for humans. He first makes a cast of what's left of the animal's amputated limb, fills the cast with plaster and produces a replica of the leg. 

The replica must then be modified, with the plaster shaved away or filled in, to make sure it bears the animal's weight in the best way and enables it to walk with a normal gait. That takes several fittings, with the process lasting up to a month. The limb is then secured to the animal with a strap or hinge.  He makes no profit, charging only for the labor and materials, resulting in a price between $400 and $600.

Patients include Mocha, a llama who broke her right front leg, and Stumpy, a kangaroo who was forced to walk on three legs because of an injury. The artificial limb created for Stumpy has a spring in it and a dressing that has to be changed, similar to one worn by runners who have amputated appendages. The prosthetic foot will allow the kangaroo to breed. Before the owner was worried Stumpy would not be able to carry the extra weight. It would have cost approximately $2,500 but was donated by Nitsch. For many owners, emotional attachment to their animals or the need to preserve them for financial reasons is the driving force behind these surgeries.

While maimed legs and arthritis are common in birds, procedures to correct these problems are not. So far, the creation of prosthetic limbs and decision to do this surgery has been centered on individual cases.

Dr. Don Harris created new legs for Candy the cockatoo who had been attacked by her cagemate. As Candy was facing euthanasia with two mangled legs, her owners inquired if there was any other solution. Both feet were amputated with one leg amputated halfway up between the knee and the ankle. The prosthetic legs were made out of bone pins, used to join human bones together, and dental acrylic, which is used to build dental bridges in humans. The pins were used to attach the acrylic legs to the bird and the disc-like stands that served as feet to the new legs. While they feared what Candy's reaction might be, she simply woke from surgery and walked off the table.

Artificial Joints

Eduard, a Siberian crane, was implanted with an artificial joint at University of Florida 's Veterinary Medical Teaching Hospital. Since Siberian cranes are one of the most endangered types of cranes, many exist in captivity in an effort to breed and repopulate their native habitats. Unfortunately, those in captivity commonly develop severe arthritis in the tarsal joints because they are living on hard surfaces unlike the soft, mushy marshes their wild counterparts live in.

Eduard in surgery.

Dr. Avery Bennett, assistant professor of wildlife and zoological medicine at University of Florida , and Dr. Eugene O'Brien, a human hand surgeon from San Antonio with experience in finger joint replacements, performed the surgery. The joint in the crane is comparable to the human ankle joint. Eduard's cartilage had worn off, so solution they found was to cut off the ends of the bones at the top and bottom of the joint and replace the middle portion with a hinged plastic device, one that is used as an artificial joint for the human big toe. While the surgery was successful, Eduard's bones are still diseased and he is only estimated to have a few more years of breeding.

Blood Transfusion

Blood transfusions for exotic species are usually given at major zoo or preservation facilities. Each species has a different set of blood types and antibodies, so matching is a particularly difficult task given the rarity of many zoo-exhibited creatures. As a result, many of the animals have their blood banked when they become a part of the zoo because there might not be a good donor available, let alone another individual of the same species.

Here are some vignettes of blood transfusions in exotic species:

At the Sea Turtle Rehabilitation Center of Mote Marine Laboratory ( Sarasota , Florida ), a loggerhead turtle was given a blood transfusion from another turtle at the facility. The turtle had been found emaciated and aplastic anemic on a local beach. He made a good recovery, and was released back into the ocean in June of 2004.

At the National Zoo, the panda Ling-Ling was given a blood transfusion to help with her life-threatening kidney infection. The bear reportedly recovered well, but zoo officials feared that the illness might have affected her ability to reproduce.

A baby elephant at the Calgary Zoo was given a blood transfusion in hopes to provide the infection-fighting antibodies it needed that its mother could not provide through her milk. When the elephant was born, both its mother and grandmother rejected it, and zoo workers started a rigorous therapy of antibiotics and the blood transfusion to keep it alive. The blood was taken from both female relatives and was sent to a Vancouver facility to remove the plasma components. The baby was given a 50% chance of living. Thankfully, the blood transfusion worked and the elephant was stabilized.

Other Therapies

Two years ago, Dr. Greg Lewbart performed one of the first surgeries on a diseased spadefish to implant a glass eye. After the surgery, Goldeneye was attacked by his tankmates who started eating his scales, which Dr. Lewbart believes was due to his new appearance. Although he was isolated, he died weeks later after his eye fell out.