Do antibiotic bead pouches prevent infections and other complications in patients with Gustilo-Anderson Type III open lower extremity fractures?

Abstract

Antibiotic-laden beads provide high, local concentrations of antibiotics and are used to prevent infections in open fractures. This study aimed to determine if wound management with antibiotic beads was associated with fewer surgical site infections (SSI) and unplanned fracture-related operations in patients with severe lower extremity open fractures. This cohort study included patients enrolled in the Aqueous-PREP and PREPARE Open trials with a single Gustilo-Anderson (GA) type III open fracture of the lower extremity. Our primary outcome was SSI within 90 days of initial surgery. The secondary outcomes included both SSI and unplanned reoperation for infection within one year of injury and adverse renal events. We used propensity score matching to reduce bias related to several factors, including wound contamination and number of surgeries that may influence the use of antibiotic beads. We used conditional logistic regression to estimate odds ratios (ORs) for the association between antibiotic bead use and the study outcomes. Of 1039 included patients, 106 (10%) received antibiotic beads comprised primarily of vancomycin (95%) and tobramycin (77%). After propensity score matching, the association of antibiotic beads and SSI within 90 days of initial surgery did not reach statistical significance (OR = 1.9, 95% CI 1.0 - 3.8, p = 0.06). Bead use was associated with an increased odds of SSI within the year following injury (OR = 2.0, 95% CI 1.1 - 3.6, p = 0.02) and an increased odds of unplanned reoperation for infection (OR = 2.0, 95% CI 1.1 - 3.8, p = 0.03). Bead use was not associated with renal serious adverse events. Patients with severe lower extremity open fractures treated with antibiotic beads had greater odds of SSI and unplanned reoperation for infection in the year following injury; however, antibiotic bead formulation was not standardized and could potentially influence the results of this study. These findings challenge the previously reported effectiveness of antibiotic-laden beads from retrospective studies. A randomized trial examining this treatment strategy is warranted.