Establishing a Training Model for Side-to-Side Anastomosis using Rat Femoral Vessels: Immediate and Delayed Patency

Side-to-side anastomoses are a relatively newer and more difficult technique used in neurovascular surgery for complex aneurysms/lesions. In view of the complex surgical technique and the infrequent clinical opportunities to acquire skills relevant to this surgery, laboratory training assumes great importance. The authors studied the feasibility of establishing a training model for performing side-to-side anastomosis using rat femoral vessels and compared the immediate and delayed patency rates in this animal model.

After Institutional Animal Ethics Committee clearance, 16 Sprague-Dawley rats were used in this prospective study between August 2013 and March 2015. Using the standard groin incision, the femoral vessels were dissected. After applying temporary clamps, opening of approximately 3-4 mm (at least double the diameter of the wider vessel) of length was made on the facing surfaces of both vessels. 10-0 nylon was used for anastomosis. The clamps were released, and the anastomoses patency confirmed. Leg movements following the anastomoses were studied. The animals were subsequently sacrificed to assess delayed patency.

The immediate patency rate was 87.5% (14/16). The delayed patency rate (mean follow-up 209 days) was 53.8% (7/13). Three rats died during the follow-up period. The mean clamp duration and suturing time was 57.25 and 41.50 min in the first eight cases and 57.50 and 36.75 min in the last eight experiments, respectively.

This animal model was found to be extremely useful for training in the difficult art of side-to-side anastomoses. The need of the hour is to establish well-planned training programs in centers with animal research facilities and use such models. This will promote younger colleagues and trainees to take up and perfect this difficult art. The present work could be used as a baseline study in this direction.