EVALUATION OF MUSCLE FLAPS IN THE TREATMENT OF INFECTED AORTIC GRAFTS

Standard therapy for abdominal aortic graft infection involving resection of the graft and extraanatomic bypass carries significant morbidity and mortality rates. The present study evaluates the feasibility of combining in situ graft replacement with a highly vascular tissue flap as an alternative to this problem. In 52 pigs a segment of a polytetrafluoroethylene graft was interposed in the infrarenal abdominal aorta. Staphylococcus aureus was used to infect the graft. One week later the animals were divided into six treatment groups. Group 1 (control) had debridement of the retroperitoneum only; group 2 had debridement with replacement of the graft; group 3 consisted of animals with the infected graft left in place and the graft wrapped with a rectus abdominis flap; group 4 is similar to group 3 except the seromuscularis of the jejunum was used to wrap the infected graft; in group 5 the graft was changed, and a rectus abdominis island flap was wrapped around the graft; and finally, group 6 was similar to group 5 except that the flap was obtained from the seromuscularis of the jejunum. Two weeks later, graft patency and infection status were assessed at reoperation. The incidence of graft infection was significantly reduced in groups 5 (0 of 10; p < 0.01) and 6 (1 of 10; p < 0.02) compared with group 1 (7 of 10), and the incidence of graft thrombosis was also greatly reduced in groups 5 (2 of 10) and 6 (1 of 10) and 4 (2 of 6), but all grafts were thrombosed at reoperation. These results suggest that vascularized tissue flaps are effective in controlling the infectious process and thus may allow in situ replacement of infected abdominal aortic grafts.