Debridement, antibiotic, and implant retention (DAIR) is an accepted treatment of early and late acute Total Knee Arthroplasty (TKA) infections. DAIR failure may adversely affect the outcome of a subsequent two-stage exchange arthroplasty. Controversy exists on risk factors that can affect DAIR's results.
The aim of the study is to review presurgical, intrasurgical and postsurgical variables that could affect DAIR's result.
A retrospective study of 27 DAIRs performed between 2015–2019 to treat late acute TKA infections was carried out. Patients were divided into two groups depending on DAIR's outcome [Healing (H) vs non-healing group (NH)] according on the Delphi-based multidisciplinary consensus criteria on success after treatment of periprosthetic joint infection.
We reviewed presurgical variables, including epidemiological variables (Age, Sex, comorbidities, ASA, Charlson, BMI, alcohol dependency), prosthesis variables (prosthesis type, primary cause of operation, primary TKA surgery center), infection variables (concomitant infection, previous antibiotic treatment, c-reactive protein, synovial WBC count, synovial % PMN, pathogen), KLIC score and CRIME 80 score. Surgical variables such as surgery duration and type of surgery (elective vs urgent). Post-surgical variables like antibiotic treatment duration and destination at discharge.
Normal distribution was assessed by Shapiro-Wilk test. Mann Whitney U test was used to compare the two independent sample variables. Chi-squared test was used for qualitative variables. P-value was established at 0.05 and statistical power at 80%.
Infection Healing was achieved in 63% of patients. In presurgical variables, alcohol dependency, hypertension, liver disease, previous surgery performed in another institution were more frequent in NH group (p< 0.05). KLIC score value equal or greater than 4 had a higher risk of surgical failure (p < 0.05).
Regarding surgical variables, the healing group had more negative cultures than de non-healing one (p<0.05). Regarding post-surgical variables, long term antibiotic treatment (six months) achieved more healing after DAIR (p<0.05).
Alcohol dependency, hypertension, liver disease and KLIC score values equal or greater than 4, may increases the risk of DAIR failure. Finally, we observed that the long-term antibiotic treatment (6 months) favors healing after DAIR.