Outcomes of Early and Late Muscle Flap Salvage of Complicated Lower Extremity Vascular Grafts

Introduction: Muscle flaps are commonly used to protect high-risk vascular grafts in the lower extremities. This study aimed to identify differences between early and late salvage procedures. Methods: Patients undergoing lower extremity vascular reconstruction with muscle flap coverage at a tertiary medical center from 2017 to 2023 were identified. Data included demographics, procedure details, and complications. The study compared early (placed at index or ≤7 d after vascular surgical procedure) versus delayed (>7 d) flap inset. Primary outcomes included rates of infection, hematoma, seroma, necrosis, wound dehiscence, flap failure, and patency of the vascular repair. Secondary outcomes included culture results from the surgical site. Results: Eighty-one patients met inclusion criteria. Early flaps were inset in 53% of cases, and 47% were delayed. Sartorius flaps were most common (53%), followed by gracilis flaps (37%). The indication for flap coverage significantly varied between immediate and delayed flaps (p = 0.004), with immediate more commonly placed for tissue coverage (37%) and delayed inset to address infection (68%). Flap survival (86.1% vs. 76.3%, p = 0.261) and graft patency (74.4% vs. 68.4%, p = 0.55) were similar between groups. Rates of infection, seroma, hematoma, and wound dehiscence did not differ significantly. Regression analysis did not find associated factors with complication incidence. Enterobacter infections were more common in the delayed group (15.8% vs. 2.3%, p = 0.031). Conclusion: This study showed no difference in outcomes between immediate and delayed muscle flaps placed over vascular grafts. Delayed procedures show a greater prevalence of certain bacteria in delayed flaps.