Moving Toward a Near-Total Reduction, Refinement, and Replacement of Live Animal Use in Microvascular Training.

Simulation training in microsurgery primarily relies on live rat models due to their high-fidelity physiological characteristics, which presents ethical and educational challenges. The increasing emphasis on reducing, replacing, and refining (3Rs) animal use calls for alternative training models that can offer similar educational benefits. We developed a hybrid microvascular training curriculum incorporating non-living models, such as chicken thigh abductor profundus muscle flaps, pork belly intramuscular perforator flap models, and the Micropump for flow-capable microvascular anastomosis training. Trainees progress from basic instrument handling and 2D suturing to more complex microvascular dissections and anastomoses. Skills are evaluated using objective measures such as hand motion analysis, time, economy of movement, and both structural and physiological patency outcomes. The hybrid curriculum has demonstrated a significant reduction in live animal use, estimated up to 80% per trainee (decreasing from approximately 10 rats to just 2 per trainee) while maintaining high educational value. Trainees achieve critical microsurgical competencies through non-living models, with outcomes comparable to traditional live model-based training. Objective assessments show improvements in hand motion, time efficiency, and movement economy, with physiological patency rates closely matching those in live models. This hybrid curriculum addresses both the ethical concerns of animal use and the educational needs of trainees. By incorporating high-fidelity, non-living models and standardized objective assessments, the curriculum provides a viable alternative to live model training. Ongoing validation studies show promising results, suggesting that this curriculum can effectively replace traditional methods without compromising skill acquisition or clinical relevance. Continued refinement of the curriculum is needed to validate its effectiveness against traditional training methods and further reduce live animal usage. The hybrid microvascular training curriculum represents a significant advancement in microsurgical education. By reducing reliance on live animal models and integrating objective skill assessment, it promotes ethical training practices aligned with the 3Rs principles. This curriculum has the potential to revolutionize microsurgical training globally, with future developments aiming to completely replace live animal use.