Methods: Using Medicare claims, we compared outcomes following hip and knee arthroplasty in intervention vs. control states. Interventions included pre-operative chlorhexidine bathing, Staphylococcus aureus screening and decolonization with nasal mupirocin, and alcohol-containing preoperative skin preparation. Between 5/2011 and 10/2011, educational materials were shared and IHI hosted a series of hospital calls. We used ICD-9 codes 996.66, 996.67, and 998.59 to identify SSI events within 90 days of surgery. We analyzed data from both the 5/2010-4/2011 baseline period and the 11/2011-9/2013 post-intervention period. We compared outcomes in intervention vs. control states using logistic regression mixed effects models adjusted for age, gender, and comorbidities, clustering by hospital and state. We evaluated the interaction between study period and arm to assess the intervention effect (difference-in-difference approach).
Results: Baseline individual-level demographics and comorbidities were well matched between intervention and control states. In intervention states, 197 hospitals participated in the intervention. We found a 15% greater decline in SSI rates in intervention vs. control states for hip arthroplasty (OR 0.85, 95% confidence interval [CI] 0.75-0.96, p 0.01), with SSI rates declining from 2.0% to 1.6% in intervention states. We found a 12% greater decline in intervention vs. control states for knee arthroplasty (OR 0.88, 95% CI 0.78-0.99, p 0.04), with SSI rates declining from 1.7% to 1.3% in intervention states.
Conclusion: Our analysis demonstrated significant state-wide impact on SSI outcomes associated with dissemination of SSI prevention strategies via state nodes, suggesting spread of practice improvements to non-participating hospitals linked within regional networks.
M. S. Calderwood,
M. V. Murphy, None
G. Parry, None
D. Goldmann, None
R. Platt, None
S. S. Huang, Sage Products: ABATE Study Investigative Team Member , Contributed product for ABATE Study
Molnlycke: ABATE Study Investigative Team Member , Contributed product for ABATE Study