Abstract: Objective To analyze and describe the learning curve of radial artery catheterization under ultrasound-guided dynamic needle tip positioning (DNTP) by anesthesia residents in Peking Union Medical College Hospital and to explore the learning intensity of supervision practice required to master this technique. Methods From January 2018 to June 2018, the learning records of two anesthesia residents in the Peking Union Medical College Hospital who perform radial artery catheterization under ultrasound-guided DNTP technique were used to describe the learning curve of cumulative sum analysis (CUSUM). The learning intensities were explored to improve the attempts and time needed for successful catheterization, first-attempt and overall success rates. The evaluation indexes before and after reaching the learning intensity were compared. Results Taking the attempts and time needed for successful catheterization, and the first and overall success rate as the evaluation indexes, the learning intensity required for the two trainees to master DNTP was 29/36, 29/29, 29/36 and 14/11 cases. After reaching this learning intensity, the number of operations required for successful puncture and catheterization decreased significantly (P＜ 0.05), and the time required, the first time and the overall success rate improved. Conclusions Considering the attempts and time needed for successful catheterization, first-attempt and overall success rates the learning intensity of the supervision practice needs to reach 36 cases.

Key words: learning curve, anesthesiology, education, vascular access