Developing and Evaluating a Novel Vessel Ligation Simulator Designed for Teaching Surgical Knot-Tying: A Mixed-Methods Study

Abstract

Abstract Background: Surgical knot-tying is a fundamental learning subject for surgical novices. However, no existing knot-tying training simulator offers a direct objective measurement of knot security, a critical feature of professional performance in this skill. This study aims to bridge this gap by developing a novel knot-tying simulator capable of assessing knot security objectively. Its educational impact was also investigated through professional user evaluation.Methods: A three-phase mixed-methods research study was conducted from August 2021 to September 2022. The first phase involved developing and manufacturing a novel vessel ligation simulator that measured the pressure-holding ability of knots, serving as an indicator of knot security, through post-ligation pressure testing. The second phase involved the participation of expert surgeons (n = 6) and Year-5 medical students (n = 30) in product evaluation. The final phase was a mixed-methods data analysis to determine the educational impact of the simulator. The collected data included participants’ demographics, prior experience in surgical knot-tying, performance metrics on the simulator, experts’ responses to a five-point Likert scale survey of simulator validity, novices’ responses to a 10-point scale survey of self-confidence in mastering surgical knot-tying skills before and after the training course, and their overall perceptions regarding the learning experience associated with the simulator.Results: The simulator was crafted using 3D-printing technology. The experts gave it high scores in face and content validity, with mean scores of 4.5 and 4.77, respectively. Twenty-four novice participants (80%) achieved knot security in vessel ligation by the end of the 3-hour training course, though they required more time for task completion compared to experts. Furthermore, all novice participants reported a marked increase in their post-class self-confidence in skill mastery. The unanimous approval from the novices highlighted the simulator's effectiveness in enhancing their learning, especially its high-fidelity design and objective feedback. This facilitated their reflection and motivation for the post-class deliberate practice.Conclusion: This study not only validates our hypothesis regarding the appropriateness of pressure-holding ability in teaching surgical knot-tying but also establishes a comprehensive methodological framework beneficial for curriculum developers to design effective simulation-based skill training in surgery.