title: Comparison of premedication with buprenorphine or methadone with meloxicam for postoperative analgesia in dogs undergoing orthopaedic surgery.
abstract: OBJECTIVE
  To determine whether methadone, administered before orthopaedic surgery, results in improved postoperative analgesia compared to buprenorphine.
  
  
  METHODS
  Thirty-eight dogs undergoing orthopaedic surgeries (the majority being tibial tuberosity advancement or elbow arthrotomy) were premedicated with 0 · 03 mg/kg acepromazine and either 20 µg/kg buprenorphine or 0 · 5 mg/kg methadone, intramuscularly, allocated randomly. Anaesthesia was induced with propofol intravenously to effect and maintained with isoflurane in oxygen. 0 · 2 mg/kg meloxicam was administered at anaesthetic induction. Sedation was assessed by means of a dynamic interactive visual analogue and simple descriptive scales and pain by dynamic interactive visual analogue and the short form Glasgow composite pain scales, by a single observer blinded to treatment group at intervals for 8 hours following premedication.
  
  
  RESULTS
  Sedation scores were higher than baseline in both groups following premedication until the end of the assessment period (P = 0 · 0001), with no differences between groups. Pain scores were lower overall in dogs premedicated with methadone (dynamic interactive visual analogue scale P = 0 · 048; short form Glasgow composite pain scale P = 0 · 0045), and these dogs required less additional analgesia (42%, compared to 79% premedicated with buprenorphine, P = 0 · 045).
  
  
  CONCLUSIONS
  At the doses investigated, methadone produced superior analgesia to buprenorphine for 8 hours postoperatively in dogs undergoing orthopaedic surgery.
authors.affiliation: Department of Clinical Veterinary Sciences, University of Bristol, Bristol, BS40 5DU.
authors.forename: J R
authors.initials: JR
authors.lastname: Hunt
authors.forename: P M
authors.initials: PM
authors.lastname: Attenburrow
authors.forename: L S
authors.initials: LS
authors.lastname: Slingsby
authors.forename: J C
authors.initials: JC
authors.lastname: Murrell
mesh_terms: D000075:Acepromazine / Q000008:administration & dosage; D000698:Analgesia / Q000379:methods / Q000662:veterinary*; D000818:Animals; D002047:Buprenorphine / Q000008:administration & dosage; D054810:Deep Sedation / Q000379:methods / Q000662:veterinary; D004285:Dogs / Q000601:surgery*; D005260:Female; D007273:Injections, Intramuscular / Q000662:veterinary; D008297:Male; D000077239:Meloxicam; D008691:Methadone / Q000008:administration & dosage; D019637:Orthopedic Procedures / Q000379:methods / Q000662:veterinary*; D011184:Postoperative Period; D011229:Preanesthetic Medication / Q000379:methods / Q000662:veterinary*; D013843:Thiazines / Q000008:administration & dosage; D013844:Thiazoles / Q000008:administration & dosage; D013977:Tibia / Q000601:surgery
chemical_list: D013843:Thiazines; D013844:Thiazoles; D002047:Buprenorphine; D000075:Acepromazine; D008691:Methadone; D000077239:Meloxicam