The dorsalis pedis bypass--moderate success in difficult situations.

Recent reports have documented excellent results for inframalleolar reconstructions. We reviewed our outcomes for dorsalis pedis bypass and report a more modest rate of success. We analyzed reasons for failure. Sixty-nine patients underwent 73 dorsalis pedis bypass procedures between 1984 and 1991. Seventy-eight percent of the patients were diabetics. Inflow was from the external iliac in 1, femoral in 35, popliteal in 34, and tibial in 3. The operative indication was gangrene in 57%, ulcer in 22%, and rest pain in 21%. Forty-six percent of limbs had foot infection, with six requiring minor amputation before the bypass and 24 requiring minor amputation after bypass. There was one perioperative death. Twenty-nine grafts failed over the course of the series. The primary patency rate at 2 years was 59.2%. The limb salvage rate was 73.5%. Of the 10 perioperative failures, four were due to continued foot infection, four to marginal vein quality, and two to skin necrosis of the bypass incisions. Graft failure occurred at 3 to 30 months in 10 of 14 patients who had deficient anterior arches, with segmental occlusion of the dorsalis pedis or its branches. Six of the 14 patients with extensive infections of the forefoot or extensive heel ulcers required amputation with patent bypasses. In dorsalis pedis bypass, failure to achieve limb salvage was more likely in patients with marginal vein quality, deficient anterior pedal arches, and extensive foot infection. In patients where the chance of failure appears to be unacceptably high, primary amputation should be considered.