title: Comparative physiologic effects of telazol, medetomidine-ketamine, and medetomidine-telazol in captive polar bears (Ursus maritimus).
abstract: The cardiopulmonary effects of three drug combinations in polar bears (Ursus maritimus) were studied. In 1995, five adult polar bears received i.m. injections of either 8.2 +/- 1.3 mg/kg of Telazol or a combination of 159 +/- 34 microg/kg of medetomidine with 4 +/- 0.8 mg/kg of ketamine in a crossover design. Significantly higher mean arterial pressure, lower heart rate, and lower partial pressure of arterial oxygen (Pao2) occurred with medetomidine-ketamine. In 1996, six adult polar bears were immobilized with i.m. injections of either 8.2 +/- 2 mg/kg of zolazepam-tiletamine or a combination of 74.8 +/- 11.8 microg/kg of medetomidine plus 2.2 +/- 0.3 mg/kg of zolazepam-tiletamine in a crossover design. Significantly higher mean arterial pressure and lower heart rate, base excess, and Pao2 occurred with medetomidine-zolazepam-tiletamine compared with zolazepam-tiletamine alone. Hypertension, bradycardia, and decreased Pao2 were observed with both medetomidine-ketamine and medetomidine-zolazepam-tiletamine. Both combinations should be well tolerated by healthy bears, but both have the potential to produce adverse effects in animals with cardiopulmonary disease. Zolazepam-tiletamine produced minimal adverse cardiopulmonary effects, consistent with the wide margin of safety of this combination in bears. The analgesic effect of zolazepam-tiletamine was apparently poor on the basis of the marked increases in pulse rate and mean arterial pressure after noxious stimuli.
authors.affiliation: Department of Veterinary Anesthesiology, Radiology, and Surgery, Veterinary Teaching Hospital, Western College of Veterinary Medicine, Saskatchewan, Canada.
authors.forename: N A
authors.initials: NA
authors.lastname: Caulkett
authors.forename: M R
authors.initials: MR
authors.lastname: Cattet
authors.forename: J M
authors.initials: JM
authors.lastname: Caulkett
authors.forename: S C
authors.initials: SC
authors.lastname: Polischuk
mesh_terms: D019162:Anesthetics, Combined; D000778:Anesthetics, Dissociative; D000818:Animals; D000836:Animals, Zoo; D001146:Arrhythmia, Sinus / Q000139:chemically induced / Q000662:veterinary; D001794:Blood Pressure / Q000187:drug effects; D018592:Cross-Over Studies; D004338:Drug Combinations; D005260:Female; D006339:Heart Rate / Q000187:drug effects; D006993:Hypnotics and Sedatives; D007103:Immobilization; D007273:Injections, Intramuscular / Q000662:veterinary; D007649:Ketamine; D008297:Male; D020926:Medetomidine; D010100:Oxygen / Q000097:blood; D012119:Respiration / Q000187:drug effects; D013992:Tiletamine; D001503:Ursidae / Q000502:physiology*; D015041:Zolazepam
chemical_list: D019162:Anesthetics, Combined; D000778:Anesthetics, Dissociative; D004338:Drug Combinations; D006993:Hypnotics and Sedatives; C006131:tiletamine, zolazepam drug combination; D013992:Tiletamine; D007649:Ketamine; D015041:Zolazepam; D020926:Medetomidine; D010100:Oxygen