title: A comparison of xylazine, acepromazine, meperidine and medetomidine as preanesthetics to halothane anesthesia in dogs.
abstract: The preanesthetic properties of medetomidine, a novel alpha 2-adrenergic agonist, were compared to the preanesthetic properties of acepromazine, zylazine and meperidine prior to halothane anesthesia. The premedications were given to 23 randomly selected laboratory beagles in doses with sedative effects equal to the 10 micrograms/kg used in the medetomidine group. These dogs also received 0.04 mg/kg of atropine prior to the preanesthetic. A group of 7 dogs with a high medetomidine dose (40 micrograms/kg) was included in the study. Cardiopulmonary and respiratory parameters were recorded at 10 min intervals during surgical stimulus. Dogs receiving 40 micrograms/kg of medetomidine showed bradycardia, but higher blood pressures than dogs in the other groups. Adequate oxygen saturations and perfusion were recorded in all groups. The low 10 micrograms/kg dose of medetomididine had a halothane sparing effect comparable to the other premedications, while the 40 micrograms/kg of medetomidine group showed a clear decrease in halothane consumption. The sedative effect of 10 micrograms/kg of medetomidine was in some instances inadequate for proper manipulation of the dogs, but 40 micrograms/kg produced excessive sedation. Atropine was found to counteract the medetomidine induced bradycardia.
authors.forename: M P
authors.initials: MP
authors.lastname: Räihä
authors.forename: J E
authors.initials: JE
authors.lastname: Räihä
authors.forename: C E
authors.initials: CE
authors.lastname: Short
mesh_terms: D000075:Acepromazine / Q000494:pharmacology; D000316:Adrenergic alpha-Agonists / Q000494:pharmacology*; D000818:Animals; D002319:Cardiovascular System / Q000187:drug effects; D004285:Dogs; D005260:Female; D006221:Halothane; D007093:Imidazoles / Q000494:pharmacology*; D020926:Medetomidine; D008614:Meperidine / Q000494:pharmacology; D011229:Preanesthetic Medication; D014991:Xylazine / Q000494:pharmacology
chemical_list: D000316:Adrenergic alpha-Agonists; D007093:Imidazoles; D014991:Xylazine; D000075:Acepromazine; D008614:Meperidine; D020926:Medetomidine; D006221:Halothane