Ex Vivo Rabbit: A Novel High-Fidelity Training Model for Microsurgical and Supermicrosurgical Training

The development of appropriate microsurgical and supermicrosurgical skills is essential for reconstructive surgeons. Training courses frequently employ in vivo models, which have various drawbacks: Limited availability, high cost, and/or ethical conflicts. To overcome these limitations, we looked for an inert model that was analogous to the gold standard in vivo, surpassing the classic ex vivo models at the same time.

We studied the ex vivo rabbit as an animal training model by means of 10 specimen dissections, microscopically analyzing the mean caliber and length of its main vascular pedicles and comparing them to those of the most common flaps and recipient vessels employed in reconstructive surgery. We designed a routine with increasingly difficult exercises, which we propose as a training plan.

The rabbit's main vascular pedicles have a mean caliber of 0.4 mm (internal mammary), 0.8 mm (iliolumbar), 0.9 mm (brachial), 1.2 mm (femoral), 1.5 mm (renal), 1.9 mm (common carotid), and 2.8 mm (aorta). They allow for a progressive increase in the level of complexity, as well as the practice of a wide variety of techniques (end-to-end anastomosis between vessels of different sizes, end-to-side anastomosis, neurorrhaphies, nerve transfers, ortho- and heterotopic replants, and free flaps).

The ex vivo rabbit serves as a valid alternative to other recognized high-fidelity microsurgical models, overcoming the limitations of in vivo-it is easily accessible, inexpensive, and inert-as well as ex vivo-it offers a wide range of calibers and the possibility of practicing advanced techniques-models which have been used in the past.