title: A comparison of injectable anesthetic combinations in horses.
abstract: Six combinations of injectable anesthetic agents were administered to six adult horses in a Latin square design. The drug combinations were xylazine-ketamine, xylazine-butorphanol-ketamine, xylazine-tiletamine-zolazepam, xylazine-butorphanol-tiletamine-zolazepam, detomidine-ketamine, and detomidine-butorphanol-ketamine. Measured variables were heart rate, respiratory rate, systolic blood pressure, arterial pH (pHa), PaCO2, PaO2, recumbency time, and number of attempts necessary to stand. Quality of induction and recovery, muscle relaxation, and response to stimulus were evaluated subjectively. The horses required significantly more attempts to stand after administration of xylazine-tiletamine-zolazepam, xylazine-butorphanol-tiletamine-zolazepam, and detomidine-ketamine than after xylazine-ketamine, xylazine-butorphanol-ketamine, or detomidine-butorphanol-ketamine. Mean recumbency times varied from 23.0 minutes with xylazine-ketamine to 41.3 minutes with xylazine-butorphanol-tiletamine-zolazepam. There were significant differences in mean heart rates at minute 15, mean respiratory rates at minutes 5, 10 and 15, and mean systolic blood pressures at minute 10 of anesthesia. There were no significant differences in pHa, PaCO2 or PaO2.
authors.affiliation: Department of Small Animal Medicine and Surgery, Texas A&M University, College Station 77843.
authors.forename: N S
authors.initials: NS
authors.lastname: Matthews
authors.forename: S M
authors.initials: SM
authors.lastname: Hartsfield
authors.forename: J L
authors.initials: JL
authors.lastname: Cornick
authors.forename: J D
authors.initials: JD
authors.lastname: Williams
authors.forename: A
authors.initials: A
authors.lastname: Beasley
mesh_terms: D000136:Acid-Base Equilibrium / Q000187:drug effects; D000771:Anesthesia, Intravenous / Q000662:veterinary*; D000777:Anesthetics / Q000008:administration & dosage; D000818:Animals; D001784:Blood Gas Analysis / Q000662:veterinary; D001794:Blood Pressure / Q000187:drug effects; D002077:Butorphanol; D002245:Carbon Dioxide / Q000097:blood; D005260:Female; D006339:Heart Rate / Q000187:drug effects; D006736:Horses / Q000502:physiology*; D007093:Imidazoles; D007649:Ketamine; D009126:Muscle Relaxation / Q000187:drug effects; D010100:Oxygen / Q000097:blood; D012119:Respiration / Q000187:drug effects; D013992:Tiletamine; D014991:Xylazine; D015041:Zolazepam
chemical_list: D000777:Anesthetics; D007093:Imidazoles; D002245:Carbon Dioxide; D014991:Xylazine; D013992:Tiletamine; D007649:Ketamine; C041255:detomidine; D015041:Zolazepam; D002077:Butorphanol; D010100:Oxygen