Arteriovenous anastomosis learning curve using low cost simulator

Abstract Background In order to reduce difficulties with learning surgical techniques, supplementary tools for training were developed. This paper describes the learning curve followed by student volunteer research subjects who used an alternative model for practicing vascular anastomosis. Objectives To evaluate the vascular anastomosis technique learning curve and development of manual skills using a low-cost experimental model. Methods Experimental and prospective study using end-to-side vascular anastomosis in latex balloons over five successive phases, initiated after theoretical and practical guidance given by experienced vascular surgeon. The study subjects were six undergraduate medical students from Universidade Federal da Paraíba (UFPB), João Pessoa, PB, Brazil, in their third to fifth years of the course. Cluster analysis was used to interpret the data collected on the quality of anastomoses and the time taken. Results The time taken to perform anastomosis reduced for all students, with statistical differences from phase 1 compared to phases 4 and 5. There was also a trend to increasing scores on the quality index as the phases progressed. However, no statistical differences were detected using the Friedman test, which is appropriate for data measured with ordinal levels (quality was assessed on a scale of 1 to 5). Conclusions It was found that the training model used was effective for increasing learning of this technique. It is believed that future studies with larger samples or a higher number of phases could demonstrate both reduced time and improved quality of the anastomoses performed with statistical significance.

摘要 研究背景：为降低外科技术的学习难度，辅助训练工具已被开发。本文阐述了使用替代模型开展血管吻合（vascular anastomosis）练习的学生志愿者研究对象的学习曲线情况。
研究目的：评估采用低成本实验模型进行血管吻合技术学习与手工技能提升的学习曲线。
研究方法：本研究为实验性前瞻性研究，由经验丰富的血管外科医师提供理论与实践指导后，受试者在乳胶气球（latex balloons）上完成端侧血管吻合（end-to-side vascular anastomosis）练习，共分为5个连续阶段。研究对象为巴西帕拉伊巴联邦大学（Universidade Federal da Paraíba, UFPB）若昂佩索阿分校的6名本科医学生，处于课程的第3至第5学年。研究采用聚类分析（cluster analysis）对吻合质量与操作时长的采集数据进行解读。
研究结果：所有受试者的血管吻合操作时长均有所缩短，第1阶段与第4、5阶段的时长差异具有统计学意义。随着练习阶段推进，吻合质量指数得分呈上升趋势，但采用适用于有序分类数据（质量评分采用1至5分制）的Friedman检验（Friedman test）未检测到统计学差异。
研究结论：本研究使用的训练模型可有效提升该技术的学习效果。未来可开展更大样本量或增设更多练习阶段的研究，以证明操作时长缩短与吻合质量提升均具有统计学显著性。