Number of previous surgeries and antibiotic resistance decreases the success of local administration of antibiotic-impregnated poloxamer 407 hydrogel when managing orthopedic surgical site infections in dogs

Abstract

OBJECTIVE To report the outcome of locally administered antibiotic-impregnated poloxamer 407 (P407) hydrogel in dogs diagnosed with orthopedic surgical site infections (SSIs) and to identify risk factors for treatment failure. ANIMALS 34 client-owned dogs diagnosed with an orthopedic surgical site infection treated with local antibiotic-impregnated P407 hydrogel. PROCEDURES Medical records were reviewed of dogs receiving antibiotic-impregnated P407 hydrogel for an active orthopedic SSI between March 2018 and December 2020. The rate of successful infection clearance was calculated. Risk factors for failed treatment were evaluated with statistical analyses. RESULTS 34 dogs met the inclusion criteria. Vancomycin-impregnated P407 hydrogel (20 mg/mL) was implanted in all dogs. The rate of infection clearance was 77%. Each unit increase in the number of surgeries performed at a site before gel implantation decrease the chance of successful infection clearance by 25% (P = .005; unit OR, 0.25; 95% CI, 0.08 to 0.81). Presence of multidrug or methicillin resistance increased risk for treatment failure by 7.69 times (P = .042; OR, 0.13; 95% CI, 0.01 to 1.14). No adverse events related to gel administration were seen. CLINICAL RELEVANCE Treatment outcomes were negatively impacted by the presence of multidrug or methicillin resistance and by an increased number of surgeries before gel implantation. Local administration of antibiotic-impregnated P407 hydrogel had a high success rate with no adverse effects in this population. Local antibiotic gel administration may improve treatment outcomes in dogs with complicated SSI.