title: Comparison of lidocaine, xylazine, and xylazine/lidocaine for caudal epidural analgesia in horses.
abstract: Caudal epidural analgesia was achieved in 6 adult horses on 3 successive occasions at weekly intervals by injection of lidocaine, xylazine, and a combination of lidocaine/xylazine through indwelling epidural catheters. Analgesia was defined as a lack of response to pinprick and hemostat pressure in the skin of the perineal area. A significant (P < 0.05) difference was not found for time of onset of analgesia between lidocaine (4.3 +/- 0.8 minutes, mean +/- SEM) and the lidocaine/xylazine combination (5.3 +/- 1.3 minutes). Time to onset of analgesia after administration of xylazine was significantly (P < 0.05) longer (32.0 +/- 3.4 minutes) than that for either of the other 2 treatments. Duration of analgesia was significantly (P < 0.05) longer for the combination (329.8 +/- 6.2 minutes) than for either drug used alone (lidocaine, 87.2 +/- 7.5 minutes; xylazine, 204.2 +/- 12.9 minutes). Pulse and respiratory rates were not significantly altered by any of the drugs. Neurologic sequelae were not clinically apparent after administration of the drugs or after chronic epidural catheterization.
authors.affiliation: Veterinary Teaching Hospital, College of Veterinary Medicine, Oregon State University, Corvallis 97331.
authors.forename: T L
authors.initials: TL
authors.lastname: Grubb
authors.forename: T W
authors.initials: TW
authors.lastname: Riebold
authors.forename: M J
authors.initials: MJ
authors.lastname: Huber
mesh_terms: D015360:Analgesia, Epidural / Q000662:veterinary*; D000818:Animals; D001259:Ataxia / Q000139:chemically induced / Q000662:veterinary; D002408:Catheters, Indwelling / Q000662:veterinary; D004338:Drug Combinations; D005260:Female; D006736:Horses / Q000502:physiology*; D008012:Lidocaine / Q000009:adverse effects; D008297:Male; D010413:Penis / Q000187:drug effects; D011674:Pulse / Q000187:drug effects; D012119:Respiration / Q000187:drug effects; D014991:Xylazine / Q000009:adverse effects
chemical_list: D004338:Drug Combinations; D014991:Xylazine; D008012:Lidocaine