Microvascular surgical experimental thrombosis model: rationale and design

The rationale for the design of surgical models of microvascular thrombosis is discussed, and a new model, the arterial inversion graft (AIG), is described and evaluated in the New Zealand white rabbit. Femoral artery segments of predetermined length are excised, gently turned inside-out, and resutured into their native position. Blood flow is restored, and at varying time intervals, vessel patency is assessed through the direct "milking test." In this study, three groups of 20 arterial inversion grafts of 2, 5, and 10 mm in length are created and evaluated for patency at 1 hour and again at 7 days. The incidence of femoral artery occlusion in this model appears to be an increasing function of arterial inversion graft length both at 1 hour--30 percent (2 mm), 80 percent (5 mm), and 100 percent (10 mm)--and at 7 days--65 percent (2 mm), 90 percent (5 mm), and 100 percent (10 mm). This proportionality suggests the arterial inversion graft may be adjusted in length to provide an incidence of vessel occlusion best suited to the needs of any particular experiment.