Comparison between the effects of postanesthetic xylazine and dexmedetomidine on characteristics of recovery from sevoflurane anesthesia in horses. (March 2017)

• Record Type: Journal Article
• Authors: Guedes, Alonso G.P.; Tearney, Caitlin C.; Cenani, Alessia; Aristizabal, Fabio; Nieto, Jorge
• Is Part Of: Veterinary anaesthesia and analgesia. Volume 44:Number 2(2017)
• Page Start: 273
• Page End: 280
• Publication Date: 2017-03
• Subjects: α2-adrenergic agonist -- complications -- inhalation -- sedation; Veterinary anesthesia -- Periodicals; 636.089
• DOI: 10.1016/j.vaa.2016.04.002
• Languages: English
• ISSNs: 1467-2987

Abstract

Abstract: Objective: To compare postanesthetic xylazine and dexmedetomidine on recovery characteristics from sevoflurane anesthesia in horses. Study design: Randomized, crossover study. Animals: Six geldings, mean ± standard deviation (SD) (range), 17 ± 4 (11–24) years and 527 ± 80 (420–660) kg. Methods: Horses were anesthetized with sevoflurane for 60 minutes under standardized conditions for a regional limb perfusion study. In recovery, horses were administered either xylazine (200 μg kg −1 ) or dexmedetomidine (0.875 μg kg −1 ) intravenously. Recoveries were unassisted and were video-recorded for later evaluation of recovery events and quality by two individuals unaware of treatment allocation. Recovery quality was assessed using a 100 mm visual analog scale (VAS) (0 = poor recovery, 100 = excellent recovery), the Edinburgh Scoring System (ESS) (0–100; 100 = excellent recovery) and the mean attempt interval (MAI) (longer = better). Data are mean ± SD. Results: All recovery quality assessments (xylazine and dexmedetomidine, respectively: VAS: 71 ± 21 mm, 84 ± 13 mm; ESS: 65 ± 22, 67 ± 30; MAI: 52 ± 24 minutes, 60 ± 32 minutes) and events (first limb movement: 37 ± 8 minutes, 42 ± 10 minutes; first attempt to lift head: 44 ± 12 minutes, 48 ± 9 minutes; first attempt to sternal posture: 57 ± 28 minutes, 50 ± 7 minutes; number of head bangs: 2.0 ± 3.0, 0.5 ± 0.5; time to first attempt to stand: 72 ± 6 minutes, 78 ± 13 minutes; time to standing: 79 ± 14 minutes, 84 ± 13 minutes) did not differ significantly between treatments ( p > 0.05). Conclusions and clinical relevance: Recovery characteristics did not differ significantly between postanesthetic xylazine and dexmedetomidine following 1 hour of sevoflurane anesthesia in horses in this study. Further evaluations in more horses and in younger horses are required to confirm these results.