title: The effect of electromagnetic guidance system on early learning curve of ultrasound for novices.
abstract: BACKGROUND
  Electromagnetic guidance reveals needle alignment and position relative to the image plane on an ultrasound view. This study compared the early learning curves of novices performing ultrasound-guided needle placement with (n = 10) or without electromagnetic guidance (n = 10).
  
  
  METHODS
  Participants performed 30 ultrasound-guided needle placements using an echogenic stick (0.3-cm diameter) as a target inside a phantom model; this early learning period was divided into sequential periods (P1: 1-5, P2: 6-10, P3: 11-15, P4: 16-20, P5: 21-25, P6: 26-30 attempts).
  
  
  RESULTS
  Using an in-plane approach, the time required for needle placement in the EMG group was significantly shorter than that of the non-EMG group in P1, P2, P4, and P6 and the number of needle advances of the EMG group was significantly smaller than that of the non-EMG group in P1 and P2. Using an out-of-plane approaches, the time required for needle placement in the EMG group was significantly shorter than that of the non-EMG group in all periods, but the number of needle advances was similar between both groups in P1-P5.
  
  
  CONCLUSIONS
  The electromagnetic guidance system may be beneficial when performing ultrasound guided peripheral nerve blocks or vascular cannulation in the early learning period, especially by inexperienced operators with reducing patient risk.
authors.affiliation: Department of Anesthesiology and Pain Medicine, Anesthesia and Pain Research Institute, Yonsei University College of Medicine, Seoul, Korea.
authors.forename: Eun Jung
authors.initials: EJ
authors.lastname: Kim
authors.affiliation: Department of Anesthesiology and Pain Medicine, Anesthesia and Pain Research Institute, Yonsei University College of Medicine, Seoul, Korea.
authors.forename: Jiyoung
authors.initials: J
authors.lastname: Min
authors.affiliation: Department of Anesthesiology and Pain Medicine, Inha University College of Medicine, Incheon, Korea.
authors.forename: Jeongyun
authors.identifier: 0000-0002-4434-4783
authors.initials: J
authors.lastname: Song
authors.affiliation: Department of Anesthesiology and Pain Medicine, Inha University College of Medicine, Incheon, Korea.
authors.forename: Kyungchul
authors.initials: K
authors.lastname: Song
authors.affiliation: Department of Anesthesiology and Pain Medicine, Inha University College of Medicine, Incheon, Korea.
authors.forename: Jang-Ho
authors.initials: JH
authors.lastname: Song
authors.affiliation: Department of Anesthesiology and Pain Medicine, Anesthesia and Pain Research Institute, Yonsei University College of Medicine, Seoul, Korea.
authors.forename: Hyo Jin
authors.identifier: 0000-0002-5400-6155
authors.initials: HJ
authors.lastname: Byon
keywords: Electromagnetic fields; Learning curve; Ultrasonography