Infections of Prosthetic Grafts and Patches Used for Infrainguinal Arterial Reconstructions

Background: Prosthetic grafts are often used as alternative conduits in patients with peripheral vascular disease who do not have an adequate autologous vein for bypass. Prosthetic grafts, unfortunately, carry an increased risk of infection and are associated with increased morbidity and mortality. The goal of this study was to identify potential risk factors and subsequent outcomes associated with lower extremity prosthetic graft infections. Methods: Two hundred seventy-two lower extremity prosthetic bypasses and patches were performed at an academic medical center between 2014 and 2016. A retrospective review of patients' demographics, comorbidities, indication for surgery, type of procedures performed, and procedural characteristics was conducted. Outcomes, including limb loss and mortality, were analyzed. Results: Forty-three (15.8%) patients with graft infections were identified during a median follow-up of 668 days (interquartile range [IQR] = 588). The median time to graft infection was 43 days (IQR = 85) with Staphylococcus being the most common bacteria cultured. Infections were associated with a 30.2% rate of limb loss and a 34.9% rate of mortality. The risk of infection was 2.4 times greater among those with a history of redo surgery (95% confidence interval [CI] of the hazard ratio [HR]: 1.3, 4.3) and 2.1 times greater in women (95% CI: 1.1, 3.8), by multivariable statistics. A 1 g/dL increase in albumin level was associated with a 33.5% decrease in hazard of infection (HR: 0.67, 95% CI: 0.46, 0.96) in the multivariable model. The estimated cumulative incidence of infection for female patients with hypertension and mean albumin of 3.36 undergoing redo surgery was 19.4% at 30 days after surgery (95% CI: 10.6, 35.6) and 39.9% at 1 year (95% CI: 26.8, 59.3). Conclusions: Female gender, redo surgery, and malnutrition are associated with increased risk of prosthetic graft infections leading to a high rate of limb loss and mortality. Endovascular interventions and bypasses with vein conduits should be considered in these patients.