By Mary Ann Albright
Gazette-Times reporter | Posted: Saturday, March 10, 2007 12:00 am
Anesthesiologists help de-tusk elephant at the Oregon Zoo
Although they've provided medical care for exotic animals ranging from polar bears to cheetahs to zebras, Oregon State University veterinary anesthesiologists Craig Mosley and Conny Gunkel achieved a career highlight last month when they helped operate on Tusko, a 13,500-pound, 35-year-old Asian bull elephant living at the Oregon Zoo.
Tusko needed to be de-tusked for health and comfort reasons.
The elephant broke both his tusks decades ago. The right one was removed when he was young. The left one, though barely visible, was still there, extending from his mouth far back into his skull.
His tusk was chronically infected, and because they feared the infection might get into his bloodstream, Oregon Zoo veterinarians decided Tusko needed to have the remainder of his left tusk removed.
Mosley and Gunkel, both assistant professors in the College of Veterinary Medicine, have worked with the zoo in the past, and were tapped to assist in Tusko's procedure, along with Oregon Zoo veterinarians Mitch Finnegan and Lisa Harrenstien, OSU College of Veterinary Medicine clinical fellow Rolando Quesada, a dentist from Florida and veterinarians from Wildlife Safari in Winston.
"It's pretty unusual to do surgery on an elephant," Mosley said. "That's one of the highlights for an anesthesiologist."
"It was amazing," Gunkel agreed.
Tusko's surgery was high-risk, the veterinarians said, adding that general anesthesia is avoided on mature elephants whenever possible because of their massive size.
The surgery took place at the zoo Feb. 17, but preparation began months before.
Mosley helped design an anesthesia machine and ventilator big enough for Tusko, because such devices are not commercially available.
Tusko's trainers taught him to stick his ear through the bars of his pen, so veterinarians could insert a catheter.
He also had to be taught to lie down on a water bed. He's so heavy that it would be dangerous for him to rest on his side without cushioning during the surgery.
The operation began at 8 a.m. and lasted about five hours. Veterinarians were unable to remove a small ring of tusk near his eye, so another surgical procedure will be required in about a month.
"If you don't get it out, it will just become a festering abscess in the socket," Mosley said.
During February's operation, Mosley, 34, intubated Tusko and saw to his inhalation and anesthetic needs.
Gunkel, 34, monitored the depth of Tusko's anesthesia. She checked muscle tone in his trunk and eye movement, and took blood-pressure and heart-rate readings.
Quesada took care of Tusko's intravenous fluids, and drew periodic blood samples.
"It was an awesome opportunity," said Quesada, 29. "It was a great experience to learn from because I've never anesthetized or been involved with anesthetizing an animal of that size. I was very excited about it."
Having the OSU veterinary anesthesiologist on hand during the surgery was "a huge help," according to Finnegan.
"It was a wonderful relief for us having knowledgeable anesthesiologist watching over him so we could focus on the surgical aspects of the procedure," he said.
Tusko arrived at the Oregon Zoo in 2005 on loan from a California elephant facility; he's a former circus elephant and is used to performing under pressure. He's supposed to sire calves with Sung Surin and Rose Tu.
He did well in surgery, Mosley and Gunkel said.
He was a touch cranky when he awoke from the anesthesia because he hadn't eaten in 24 hours; otherwise, he was fine and was able to resume training after just a day of rest.
"It was kind of like a root canal," Mosley said.
on the go
Last weekend Craig Mosley, assistant professor of veterinary anesthesiology in Oregon State University's College of Veterinary Medicine, left for American Samoa, where he's spending two weeks caring for animals.
"Basically, the island has no vet, so we're going down there and providing veterinary care," he said.
Mosley's trip was organized by the Portland-based group Veterinary Ventures.
He planned to perform "lots of spays and neuters for cats and dogs," in addition to other procedures.
Mosley is the only OSU veterinarian on this trip. He hopes to get students involved in the program in the future.
On the Net: More information about Tusko is available on the Oregon Zoo Web site, www.oregonzoo.org/Cards/Elephants/tusko.htm. Video of Tusko's training in preparation for his surgery is available online at http://www.oregonzoo.org/VideoArchive/elephant_TuskoSurgery.htm