title: Comparison of epidural versus intrathecal anaesthesia in dogs undergoing pelvic limb orthopaedic surgery.
abstract: OBJECTIVE
  To compare the procedural failure rate (PFR), intraoperative rescue analgesia (iRA) probability and postoperative duration of motor block after epidural and intrathecal anaesthesia in dogs undergoing pelvic limb orthopaedic surgery.
  
  
  METHODS
  Prospective, randomized clinical trial.
  
  
  METHODS
  Ninety-two client-owned dogs.
  
  
  METHODS
  Dogs were assigned randomly to receive either lumbosacral epidural anaesthesia (EA) (bupivacaine 0.5% and morphine 1%) or intrathecal anaesthesia with the same drugs in a hyperbaric solution (HIA). Inaccurate positioning of the needle, assessed by radiographic imaging, and lack of cerebral spinal fluid outflow were considered procedural failures (PFs) of EA and HIA, respectively. Fentanyl (1 μg kg(-1) IV) was provided for intraoperative rescue analgesia, when either the heart rate or the mean arterial pressure increased by 30% above the pre-stimulation value. Its use was recorded as a sign of intraoperative analgesic failure. The motor block resolution was evaluated postoperatively. Variables were compared using Fisher's exact test, the Mann-Whitney U test and the Kaplan-Meier 'survival' analysis as relevant.
  
  
  RESULTS
  The PFRs in the EA and HIA groups were 15/47 (32%) and 3/45 (7%), respectively (p = 0.003). Differences in iRA were analysed in 26 and 30 subjects in the EA and HIA groups respectively, using Kaplan-Meier survival analysis. The iRA probability within the first 80 minutes of needle injection (NI) was higher in the EA group (p = 0.045). The incidence of dogs walking within 3 hours of NI was significantly higher in the HIA group (8/20, 40%) than in the EA group (0/17) (p = 0.004).
  
  
  CONCLUSIONS
  HIA was found to have lower PF, lower intraoperative analgesic failure and faster motor block resolution. In this study HIA was shown to provide some advantages over EA in dogs undergoing commonly performed pelvic limb orthopaedic surgery in a day-hospital regime.
authors.affiliation: Centro Veterinario Fossanese, Fossano, Italy.
authors.forename: Diego
authors.initials: D
authors.lastname: Sarotti
authors.affiliation: Clinica Veterinaria Roma Sud, Roma, Italy.
authors.forename: Roberto
authors.initials: R
authors.lastname: Rabozzi
authors.affiliation: Department of Animal Medicine, Production and Health, University of Padua, Legnaro, Italy.
authors.forename: Paolo
authors.initials: P
authors.lastname: Franci
mesh_terms: D000758:Anesthesia / Q000662:veterinary; D000779:Anesthetics, Local / Q000008:administration & dosage*; D000818:Animals; D002045:Bupivacaine / Q000008:administration & dosage; D004285:Dogs / Q000502:physiology*; D005260:Female; D006614:Hindlimb / Q000601:surgery*; D007268:Injections, Epidural / Q000662:veterinary; D007278:Injections, Spinal / Q000662:veterinary; D008297:Male; D009020:Morphine / Q000008:administration & dosage; D009407:Nerve Block / Q000379:methods / Q000662:veterinary*; D011446:Prospective Studies; D016896:Treatment Outcome
chemical_list: D000779:Anesthetics, Local; D009020:Morphine; D002045:Bupivacaine
keywords: dogs; epidural anaesthesia; orthopaedic surgery; spinal anaesthesia