Timing of Debridement, Antibiotics, and Implant Retention Within 48 Hours for Acute Knee Periprosthetic Joint Infection May Not Improve Success Rate

BACKGROUND: Debridement, antibiotics, and implant retention (DAIR) is a common first-line treatment for acute periprosthetic joint infection (PJI) following total knee arthroplasty (TKA). However, the optimal timing for DAIR remains undefined. This study aimed to evaluate whether the time from initial presentation or diagnosis to surgical intervention impacts treatment outcomes. METHODS: A retrospective cohort study was conducted on 166 patients who underwent DAIR for acute PJI after TKA between 2016 and 2022 within a regional academic health system. Patients were stratified by time to DAIR from both the first health care contact and formal PJI diagnosis: < 24, 24 to 48, and > 48 hours. The primary outcome was DAIR failure, defined as reoperation for PJI. The secondary outcomes included 90-day readmission, chronic antibiotic suppression, adverse events, and mortality. Outcomes were assessed with analysis of variance tests or chi-squares and multivariate logistic regressions. RESULTS: A DAIR failure occurred in 40.4% of cases, with no significant differences by timing from first contact (P = 0.97) or diagnosis (P = 0.84). Similarly, time to debridement was not associated with differences in readmission, chronic suppression, or adverse events. Notably, 90-day mortality was higher in patients who underwent DAIR within 24 hours of diagnosis (12.1%, P = 0.001), potentially reflecting clinical triage of higher-risk patients. Multivariable analysis analyses found that age, diabetes mellitus, and low preoperative hemoglobin were independently associated with worse outcomes. Elevated C-reactive protein was not predictive of failure or complications. CONCLUSIONS: Timing of DAIR for acute TKA PJI within early windows did not significantly affect failure or complication rates, suggesting that urgent rather than emergent intervention is appropriate. Brief delays to allow clinical optimization may be safely considered, although power may have been limited to form definitive conclusions. Larger and more robust studies are needed.