Gentamicin for prevention of intraoperative mesh contamination: demonstration of high bactericide effect (in vitro) and low systemic bioavailability (in vivo).

Abstract

Mesh infection is a severe complication after incisional hernia repair and occurs in 1-3% of all open mesh implantations. For this reason, topical antimicrobial agent applied directly to the mesh is often used procedure. So far, however, this procedure lacks a scientific basis. Two different meshes (Parietex™, Covidien; Ultrapro™, Ethicon Johnson & Johnson) were incubated with increasing amounts of three different Staphylococcus aureus strains (ATCC 25923; Mu50; ST239) with or without gentamicin and growth ability were determined in vitro. To further address the question of the systemic impact of topic gentamicin, serum levels were analyzed 6 and 24h after implantation of gentamicin-impregnated multifilament meshes in 19 patients. None of the gentamicin-impregnated meshes showed any bacterial growth in vitro. This effect was independent of the mesh type for all the tested S. aureus strains. In the clinical setting, serum gentamicin levels 6h after implantation of the gentamicin-impregnated meshes were below the through-level (range 0.4-2.9mg/l, mean 1.2±0.7mg/l). After 24h the gentamicin serum levels in all patients had declined 90-65% of the 6h values. Local application of gentamicin to meshes can completely prevent the growth of even gentamicin-resistant S. aureus strains in vitro. The systemic relevance of gentamicin in the clinical controls showed to be very low, without reaching therapeutic concentrations.