The thrombosed prosthetic graft is a risk for infection of an adjacent graft.

BACKGROUND

A bland thrombosed graft may be more susceptible to the future risk of infection than a patent graft. Once infected, that graft can threaten other patent grafts. Therefore, the purpose of the following study was to assess the role a thrombosed graft might play in infection of contiguous patent bypasses.

METHODS

From 1990, a retrospective review was performed using the operative and medical records of cases in which a prosthetic graft infection was identified arising in association with an adjacent thrombosed graft.

RESULTS

A total of 22 cases of prosthetic arterial bypass infection were treated at our institution from January 1990 through September 1995. Of these, 7 (32%) were identified by the operative report as arising in a thrombosed prosthetic graft and spreading to an attached or adjacent patent prosthetic graft. All patients had multiple bypasses prior to infection, mean 5.4 +/- .75 (range 3 to 8). All thrombosed infected grafts were infrainguinal polytetrafluoroethylene (PTFE) for limb salvage: 6 femoralpopliteal and 1 femorotibial. Mean interval time between placement of the primarily infected graft and removal was 14.6 +/- 6.7 months (range 1 to 53). The secondarily infected patent bypasses were inflow procedures to the same limb in 6 cases: 1 aortofemoral, 2 ileofemoral, 2 axillofemoral, and 1 femoral femoral graft. The thrombosed infrainguinal bypass was directly attached to the secondarily infected bypass in 5 cases and near but not attached in 1 case. One secondarily infected prosthetic graft was a femoraldistal bypass placed adjacent to the thrombosed graft. Four patients had above-knee amputations with a clinically bland graft divided at the time of amputation. In these 4 patients and 2 additional cases, wet gangrene or infection was present in the distal extremity prior to the development of prosthetic graft infection. At the point that infection became clinically apparent, the thrombosed graft was removed in all cases and the secondarily infected graft was removed in 4 of 7 cases. Overall mortality was 57%.

CONCLUSIONS

A thrombosed prosthetic graft near a patent prosthetic bypass may become secondarily infected and threaten the patent graft. We recommend total removal of any thrombosed prosthetic graft in proximity to a patent prosthetic bypass when the risk of infection is high or at the time of subsequent amputation for gangrene.