title: Ultrasound-guided nerve blocks of the pelvic limb in dogs.
abstract: OBJECTIVE
  To evaluate the efficacy of ultrasound-guidance in nerve blockade of the sciatic and saphenous nerves in dogs and to determine if this technique could allow lower anaesthetic doses to be used with predictable onset and duration of effect.
  
  
  METHODS
  Prospective randomized (for dose and leg) blinded experimental crossover trial with 10 day washout period.
  
  
  METHODS
  Six healthy female Hound dogs aged 12.3 +/- 0.5 (mean +/- SD) months and weighing 18.7 +/- 0.8 (mean +/- SD) kg.
  
  
  METHODS
  An ultrasound-guided, perineural injection was used with saline at 0.2 mL kg(-1) (Sal) or bupivacaine 0.5% at 0.05 (low dose; LD), 0.1 (medium dose; MD), or 0.2 (high dose; HD) mL kg(-1), divided 2/3 at the sciatic nerve and 1/3 at the saphenous nerve. Blocks were performed using dexmedetomidine sedation with atipamezole reversal immediately after completion of the injections. Motor/proprioceptive and sensory functions were scored using a 0-8 and a 0-2 scale, respectively. Clinically relevant blocks were defined as a motor score > or =2 and sensory score > or =1. Nonparametric methods were used for statistical analysis.
  
  
  RESULTS
  No adverse effects were noted. There was a significant difference between the treatments with bupivacaine and the saline control, but not between the three bupivacaine treatments. Success rates of clinically relevant sciatic and saphenous blocks were both 67% (CI 95% 0.22-0.96). Onset and duration of the blocks were variable; 20-160 and 20-540 minutes, respectively.
  
  
  CONCLUSIONS
  None of the bupivacaine doses was significantly superior, though there was a tendency for a better block with the high bupivacaine dose. Either the technique or the doses used need further modification before this method will be useful in clinical practice.
authors: Veterinary Medical Teaching Hospital, School of Veterinary Medicine, University of California, Davis, CA 95616 USA. yshilobenjamini@ucdavis.edu
authors: Yael
authors: Y
authors: Shilo
authors: Peter J
authors: PJ
authors: Pascoe
authors: Derek
authors: D
authors: Cissell
authors: Eric G
authors: EG
authors: Johnson
authors: Philip H
authors: PH
authors: Kass
authors: Erik R
authors: ER
authors: Wisner
mesh_terms: D018712:Analgesics, Non-Narcotic / Q000008:administration & dosage; D000818:Animals; D020927:Dexmedetomidine / Q000008:administration & dosage; D004285:Dogs; D005260:Female; D006614:Hindlimb; D009407:Nerve Block / Q000379:methods / Q000662:veterinary*; D012584:Sciatic Nerve / Q000000981:diagnostic imaging; D018084:Ultrasonography, Interventional / Q000379:methods / Q000662:veterinary*
chemical_list: D018712:Analgesics, Non-Narcotic; D020927:Dexmedetomidine