Concentration, Antibacterial Effect, and Safety of Combining Intra-articular Epsilon-Aminocaproic Acid and Vancomycin in Primary Total Knee Arthroplasty: A Randomized Study.

BACKGROUND

In this study, we aimed to investigate the intra-articular concentration, antibacterial effect, and safety of a combination of vancomycin and epsilon-aminocaproic acid (EACA) in primary total knee arthroplasty (TKA).

METHODS

There were 94 patients who underwent unilateral primary TKA and were randomized into the vancomycin plus EACA (VE) group and the vancomycin (V) group. There were 47 contemporary TKAs propensity score-matched to form the EACA (E) group. The VE group received vancomycin 30 mL (1,000 mg) plus EACA 20 mL, the V group received vancomycin plus saline, and the E group received saline plus EACA. Postoperative blood and drainage samples were collected for vancomycin analysis using liquid chromatography-tandem mass spectrometry. Perioperative blood loss, renal function, and bacterial tests for common periprosthetic joint infection pathogens were evaluated.

RESULTS

Perioperative blood loss in the VE group was equivalent to that in the E group and significantly lower than that in the V group (P < 0.01). The intra-articular vancomycin levels in the VE group were higher than those in the V group at eight and 24 hours, while the serum levels were similar. Antimicrobial effects were comparable in the VE and the V groups, both of which were superior to those in the E group. There were no cases of acute renal injury, ototoxicity, or anaphylaxis.

CONCLUSIONS

The combination of intra-articular vancomycin and EACA maintained the vancomycin concentration without impairing the antifibrinolytic function of EACA, although it did not enhance the antibacterial effect of vancomycin.