The effect of electromagnetic guidance system on early learning curve of ultrasound for novices

Eun Jung Kim, Jiyoung Min, Jeongyun Song, Kyungchul Song, Jang-Ho Song, Hyo Jin Byon

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). 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). 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. 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.