Peripheral vascular occlusive disease causing tissue ischemia of the lower extremities often results in extensive tissue loss, even primary amputation. Revascularization improved the limb salvage rate, hospitalization, and days for wounds to heal to a level comparable to that of the adequately vascularized limb. Combined revascularization and free tissue transfer has been applied as a method of extending limb salvage to these patients. Free tissue transfer combined with bypass grafting in selected patients is safe and effective. However, renal disease associated with diabetes and peripheral vascular disease, can be a strong indicator of possible reconstructive failure. The surgeon and patient should be aware of the medical and surgical complications associated with this procedure at the outset.

　　Although combined surgery for placement of a distal venous bypass and a free flap enables successful treatment of tissue loss caused by ischemia, this complex surgery has limited indications. The multiple anastomoses on the same arterial axis increase the risk of thrombosis and a certain number of venous grafts are likely to undergo late deterioration.
　　 Recently, some authors propose a new concept: the bypass flap (BF), which is based on the harvesting of an arterial axis to provide an arterial graft and a free flap supplied by a collateral branch of the graft. This technique has the advantage of decreasing vascular distal resistance, which may contribute to improvement of vessel reconstruction patency. It is simpler because the anastomoses are fewer and it presents the advantage of requiring only autologous arterial material of an appropriate diameter. Outcome in their initial series demonstrates the clinical feasibility of the new BF reconstruction technique, which allows revascularization and coverage of tissue defects using a one-piece anatomic unit.