title: EFFECT OF ACTIVE COOLING AND α-2 ADRENOCEPTOR ANTAGONISM ON CORE TEMPERATURE IN ANESTHETIZED BROWN BEARS (URSUS ARCTOS).
abstract: Hyperthermia is a common complication during anesthesia of bears, and it can be life threatening. The objective of this study was to evaluate the effectiveness of active cooling on core body temperature for treatment of hyperthermia in anesthetized brown bears (Ursus arctos). In addition, body temperature after reversal with atipamezole was also evaluated. Twenty-five adult and subadult brown bears were captured with a combination of zolazepam-tiletamine and xylazine or medetomidine. A core temperature capsule was inserted into the bears' stomach or 15 cm into their rectum or a combination of both. In six bears with gastric temperatures≥40.0°C, an active cooling protocol was performed, and the temperature change over 30 min was analyzed. The cooling protocol consisted of enemas with 2 L of water at approximately 5°C/100 kg of body weight every 10 min, 1 L of intravenous fluids at ambient temperature, water or snow on the paws or the inguinal area, intranasal oxygen supplementation, and removing the bear from direct sunlight or providing shade. Nine bears with body temperature>39.0°C that were not cooled served as control for the treated animals. Their body temperatures were recorded for 30 min, prior to administration of reversal. At the end of the anesthetic procedure, all bears received an intramuscular dose of atipamezole. In 10 bears, deep rectal temperature change over 30 min after administration of atipamezole was evaluated. The active cooling protocol used in hyperthermic bears significantly decreased their body temperatures within 10 min, and it produced a significantly greater decrease in their temperature than that recorded in the control group.
authors.forename: Larissa Mourad
authors.initials: LM
authors.lastname: Ozeki
authors.forename: Nigel
authors.initials: N
authors.lastname: Caulkett
authors.forename: Gordon
authors.initials: G
authors.lastname: Stenhouse
authors.forename: Jon M
authors.initials: JM
authors.lastname: Arnemo
authors.forename: Åsa
authors.initials: Å
authors.lastname: Fahlman
mesh_terms: D058669:Adrenergic alpha-2 Receptor Antagonists / Q000494:pharmacology*; D000758:Anesthesia / Q000009:adverse effects / Q000662:veterinary*; D000818:Animals; D000835:Animals, Wild; D001831:Body Temperature / Q000187:drug effects*; D005334:Fever / Q000139:chemically induced / Q000628:therapy / Q000662:veterinary*; D006993:Hypnotics and Sedatives / Q000009:adverse effects / Q000494:pharmacology; D007093:Imidazoles / Q000494:pharmacology*; D007103:Immobilization / Q000662:veterinary; D020926:Medetomidine / Q000009:adverse effects / Q000494:pharmacology; D001503:Ursidae; D014991:Xylazine / Q000009:adverse effects / Q000494:pharmacology
chemical_list: D058669:Adrenergic alpha-2 Receptor Antagonists; D006993:Hypnotics and Sedatives; D007093:Imidazoles; C050701:atipamezole; D014991:Xylazine; D020926:Medetomidine
keywords: Ursus arctos.; brown bears; cooling; hyperthermia; α-2 antagonist