Infection Outcomes in Implant-Based Breast Reconstruction: Five-Year Experience with the GAPS Protocol

Introduction: Surgical-site infections (SSI) are a major complication of implant-based breast reconstruction (IBBR), with no widely adopted prevention protocol. We evaluated the effectiveness of the 12-step Gloves, Antimicrobial soak, Pocket irrigation, and Sterile field (GAPS) protocol in reducing SSI after IBBR. Methods: We performed a quasi-experimental prospective cohort study with historical controls of immediate IBBR at a single academic health system (January 2018–December 2023). The GAPS protocol was implemented in December 2019; follow-up extended 90 days postoperatively. The primary outcome was SSI. Relative risks (RR), absolute risk reduction (ARR), and number needed to treat (NNT) were calculated. Results: Among 915 patients (1,500 breasts), the protocol cohort (604 patients, 994 breasts) had lower SSI rates than controls (311 patients, 506 breasts): 5.7% versus 8.7% (P = .03). The unadjusted relative risk was 0.66 (95% CI, 0.45–0.96). Across single-covariate adjustments (age, prior radiation, smoking, implant plane, seroma, and acellular dermal matrix [ADM]), the protocol remained directionally protective (RR range 0.57–0.76). In fully-adjusted multivariable models, the total effect was RR 0.76 (95% CI 0.50–1.15; P = .195), and the direct effect, adjusting for seroma as a post-exposure mediator, was RR 0.66 (95% CI 0.43–1.01; P = .053). Protocol adherence was approximately 80%, with an ARR of 2.96% and NNT of 34. Conclusion: The GAPS protocol was associated with reduced SSI after IBBR with directionally consistent protective estimates across adjusted models. These findings support structured perioperative infection-prevention protocols to improve reconstructive outcomes and reduce healthcare burden.