title: Use of needle enhancing software to improve injection technique amongst inexperienced anaesthetists performing ultrasound-guided peripheral nerves blocks in dogs.
abstract: OBJECTIVE
  To determine if the use of needle enhancing software facilitate injection technique in ultrasound-guided peripheral nerve blocks.
  
  
  METHODS
  Prospective, blinded, randomized controlled trial.
  
  
  METHODS
  Eight hind limbs from canine cadavers.
  
  
  METHODS
  The limbs were randomly allocated to two groups; software on (group I) and software off (group II). Eight anaesthetists with no previous experience of ultrasound-guided regional anaesthesia were recruited. Thirty-six procedures were carried out (18 per group). After sciatic nerve visualisation via ultrasonography, the anaesthetist introduced a needle guided by ultrasonography. When the tip of the needle was considered by the anaesthetist to be as close as possible to the nerve without touching it, 0.05 mL of methylene blue dye was injected. Parameters evaluated included: number of attempts to visualise the needle with ultrasonography, time spent to perform the technique, subjective evaluation of ease of needle visualisation, proximity of the tip of the needle to the nerve, and, at dissection of the leg, inoculation site of the dye in relation to the nerve.
  
  
  RESULTS
  Significant differences between groups were identified in relation to the number of attempts (group I: median 1, IQR: 1 - 1 attempts versus group II: median 1, IQR: 1 - 4 attempts, p = 0.019), and the relationship between the dye and the nerve during hind limb dissection (72.2% of the nerves were stained in group I versus 16.6% in group II, p = 0.003). No significant difference between groups was observed with respect to the time taken to perform the procedure (group I: median 25.5, IQR: 18.4 - 44.3 seconds versus group II: median 35.7, IQR: 18.6-78.72 seconds, p = 0.31), subjective evaluation of the needle visualization (p = 0.45) or distance between the tip of the needle and the nerve as measured from the ultrasound screen (p = 0.23).
  
  
  CONCLUSIONS
  This study identified greater success rate in nerve staining when the needle enhancing software was used. The results suggest that the use of this technique could improve injection technique amongst inexperienced anaesthetists performing ultrasound-guided peripheral nerve blocks in dogs.
authors.affiliation: Veterinary Clinical Science, Royal Veterinary College, University of London, Hatfield, UK.
authors.forename: Jaime
authors.initials: J
authors.lastname: Viscasillas
authors.forename: Livia
authors.initials: L
authors.lastname: Benigni
authors.forename: David
authors.initials: D
authors.lastname: Brodbelt
authors.forename: Hatim
authors.initials: H
authors.lastname: Alibhai
mesh_terms: D000818:Animals; D002983:Clinical Competence; D004285:Dogs / Q000601:surgery; D009339:Needles / Q000662:veterinary; D009407:Nerve Block / Q000379:methods / Q000662:veterinary*; D012584:Sciatic Nerve / Q000000981:diagnostic imaging; D012984:Software; D018084:Ultrasonography, Interventional / Q000379:methods / Q000662:veterinary*
keywords: needle visualization; peripheral nerve block; ultrasound