Economic burden of surgical management of surgical site infections following hip and knee replacements in Calgary, Alberta, Canada.

Abstract

To evaluate the cost of 1-stage and 2-stage revisions, debridement, antibiotic and implant retention (DAIR) and DAIR with liner exchange for complex surgical site infections (SSIs) following hip and knee replacements. Retrospective population-based economic analysis of patients undergoing intervention for SSIs between April 1, 2012 and March 31, 2019. The study was conducted in the Calgary zone of Alberta Health Services (AHS) in Canada. Individuals >18 years with complex SSI following hip or knee replacement. Patients with complex SSIs were identified using the AHS infection prevention and control database. A combination of microcosting and gross costing methods were used to estimate 12- and 24-month costs following the initial hospital admission for arthroplasty. Subgroup, inverse Gaussian and γ regression analyses were used to evaluate the impact of age and comorbidities on cost. In total, 142 patients with complex SSIs were identified, with a mean age of 66.8 years. Total direct medical costs in United States dollars of 2-stage revisions were ($100,992 (95% CI, 34,587-167,396) at 12 months. The 1-stage revision ($41,176; 95% CI, 23,361-58,991), DAIR with liner exchange ($41,267; 95% CI, 29,923-52,612) and DAIR ($46,605; 95% CI, 15,277-76,844) were associated with fewer costs at 12 months. Age >65 years and chronic complications of diabetes and hypertension were associated with increased costs in subgroup and regression analysis. Medical costs are highest at 12 months and for 2-stage revisions in hip and knee complex SSI cases. Further work should explore surgical outcomes correlated with costs to enhance patient care.