Comparison of analgesic efficacy of epidural methadone or ropivacaine/methadone with or without pre-operative oral tepoxalin in dogs undergoing tuberositas tibiae advancement surgery
Article first published online: 22 JUN 2012
© 2012 The Authors. Veterinary Anaesthesia and Analgesia. © 2012 Association of Veterinary Anaesthetists and the American College of Veterinary Anesthesiologists
Veterinary Anaesthesia and Analgesia
Volume 39, Issue 6, pages 618–627, November 2012
How to Cite
Bosmans, T., Piron, K., Oosterlinck, M., Gasthuys, F., Duchateau, L., Waelbers, T., Samoy, Y., Van Vynckt, D. and Polis, I. (2012), Comparison of analgesic efficacy of epidural methadone or ropivacaine/methadone with or without pre-operative oral tepoxalin in dogs undergoing tuberositas tibiae advancement surgery. Veterinary Anaesthesia and Analgesia, 39: 618–627. doi: 10.1111/j.1467-2995.2012.00744.x
- Issue published online: 5 OCT 2012
- Article first published online: 22 JUN 2012
- Received 17 August 2011; accepted 21 February 2012.
- tibial tuberosity advancement
Objective To investigate the clinical efficacy of four analgesia protocols in dogs undergoing tibial tuberosity advancement (TTA).
Study design Prospective, randomized, blinded study.
Animals Thirty-two client owned dogs undergoing TTA-surgery.
Methods Dogs (n = 8 per treatment) received an oral placebo (PM and PRM) or tepoxalin (10 mg kg−1) tablet (TM and TRM) once daily for 1 week before surgery. Epidural methadone (0.1 mg kg−1) (PM and TM) or the epidural combination methadone (0.1 mg kg−1)/ropivacaine 0.75% (1.65 mg kg−1) (PRM and TRM) was administered after induction of anaesthesia. Intra-operative fentanyl requirements (2 μg kg−1 IV) and end-tidal isoflurane concentration after 60 minutes of anaesthesia (Fe′ISO60) were recorded. Post-operative analgesia was evaluated hourly from 1 to 8 and at 20 hours post-extubation with a visual analogue scale (VAS) and the University of Melbourne Pain Scale (UMPS). If VAS > 50 and/or UMPS > 10, rescue methadone (0.1 mg kg−1) was administered IV. Analgesic duration (time from epidural until post-operative rescue analgesia) and time to standing were recorded. Normally distributed variables were analysed with an F-test (α = 0.05) or t-test for pairwise inter-treatment comparisons (Bonferonni adjusted α = 0.0083). Non-normally distributed data were analysed with the Kruskall–Wallis test (α = 0.05 or Bonferonni adjusted α = 0.005 for inter-treatment comparison of post-operative pain scores).
Results More intra-operative analgesia interventions were required in PM [2 (0–11)] [median (range)] and TM [2 (1–2)] compared to PRM (0) and TRM (0). Fe′ISO60 was significantly lower in (PRM + TRM) compared to (PM + TM). Analgesic duration was shorter in PM (459 ± 276 minutes) (mean ± SD) and TM (318 ± 152 minutes) compared to TRM (853 ± 288 minutes), but not to PRM (554 ± 234 minutes). Times to standing were longer in the ropivacaine treatments compared to TM.
Conclusions and clinical relevance Inclusion of epidural ropivacaine resulted in reduction of Fe′ISO60, avoidance of intra-operative fentanyl administration, a longer duration of post-operative analgesia (in TRM) and a delay in time to standing compared to TM.