LAUSR

Purpose Surgical site infection following total knee replacement is considered as one of the most severe postoperative complications. The presence of bacteria at the surgical site is the most important risk factor and therefore it is essential to prevent infection through appropriate preoperative skin preparation. The purpose of this study was to examine the presence and type of native bacteria on the incision site and to assess which skin preparation is most effective to sterilize those native bacteria. Methods Scrub-and-paint 2 step method was used for standard preoperative skin preparation. 150 patients who underwent total knee replacement were grouped into 3 groups- Group 1 (povidone-iodine scrub-and-paint), Group 2 (chlorhexidine gluconate paint after povidone-iodine scrub), and Group 3 (povidone-iodine paint after chlorhexidine gluconate scrub). 150 specimens of post-preparation swabs were obtained and cultured. To analyze the native bacteria at the total knee replacement incision site, 88 additional swaps were performed before skin preparation and cultured. Results The positive rate of bacterial culture after skin preparation was 5.3% (8/150). Positive rates of the groups were 12% (6/50) in group 1, 2% (1/50) in group, 2 and 2% (1/50) in group 3 and positive rates of bacterial culture after skin preparation in group 2 and group 3 were lower than in group 1 (p = 0.037). Among the 55 patients who had positive bacterial culture prior to skin preparation, 26.7% (4/15) in group 1, 5.6% (1/18) in group 2, and 4.5% (1/22) in group 3 were positive. Group 1 showed 7.64 times higher positive bacterial culture rate after skin preparation than group 3 (p = 0.084) Conclusion During skin preparation prior to total knee replacement surgery, chlorhexidine gluconate paint after povidone-iodine scrub or povidone-iodine paint after chlorhexidine gluconate scrub had a superior effect on sterilizing native bacteria compared to povidone-iodine scrub-and-paint method.