Anastomosis Lapse Index (ALI): A Validated End Product Assessment Tool in Simulated Microsurgery Training

Introduction: Over the last decade, simulation has become a principal training method in microsurgery. With an increasing move toward the use of non-living models there is a need to develop methods for assessment of microvascular skill acquisition substituting traditional patency rate. The authors present and validate a novel method of microvascular anastomosis assessment tool for formative and summative competency assessment.

Methodology and Material: 29 trainees with varying levels of experience in microsurgery undertook a 5-day microsurgery course. Two consecutive end to end microvascular anastomoses of cryo-preserved rat aortas performed on day 3 and day 5 of the course were splitted longitudinally for blinded qualitative evaluation. 4 consecutive anastomoses by two experienced microsurgeons were analyzed as a positive control. Errors potentially leading to anastomotic leak or thrombosis were identified and logged. Statistical analysis using the Kruskal-Wallis ANOVA and a two-way repeated measure ANOVA was used to measure construct and concurrent validity respectively.

Results: A total of 128 microvascular anastomoses were analyzed for both student and control groups. Ten errors were identified and indexed. There was a statistically significant difference detected between average errors per anastomosis performed between groups (p < 0.05). Average errors per anastomosis was statistically decreased on day 5 of the course compared with day 3 (p < 0.001).

Conclusions: Evaluation of anastomosis quality and patency in non-living models is possible. The proposed error list showed construct and predictive validity. The anastomosis lapse index (ALI) can serve as a formative and summative assessment tool during microvascular training.