In vivo pharmacokinetics of a gentamicin-loaded collagen sponge in acute periprosthetic infection: Serum values in 19 patients

BACKGROUND: The in vivo pharmacokinetics of gentamycin- loaded collagen fleeces in humans have not been described in the current literature. We therefore analyzed in vivo pharmacokinetics of these fleeces when used in the treatment of periprosthetic infections. PATIENTS AND METHODS: Gentamycin concentrations were measured in 19 consecutive patients with an acute periprosthetic infection. Each patient received 2-5 fleeces (130 mg gentamycin/fleece). RESULTS: Initially, the blood concentration increased to 3.2-7.2 mg/L, depending on the number of fleeces that were applied. The serum peak concentrations resulted in peak/MIC ratios of 2.5-36 for P. aeruginosa, S. aureus,and Klebsiella spp. Subsequently, the serum values decreased almost linearly below 0.3 mg/L in 18 to 62 hours. After 24 hours, the serum levels of gentamicin dropped below 2 mg/L, the toxicity threshold. INTERPRETATION: The application of 2 to 5 130-mg gentamycin-loaded collagen fleeces may be useful as an adjuvant treatment for implant-related infections, since no toxic concentrations were measured 24 hours postoperatively.