How Long Do Implanted Triclosan Sutures Inhibit Staphylococcus aureus in Surgical Conditions? A Pharmacological Model

Abstract

(1) Background: Sutures with triclosan (TS) are used to reduce the risk of surgical site infections (SSI), but most clinical trials are inconclusive. The traceability of SSI risk to antimicrobial activity in operated tissues is needed. (2) Objectives: This study aimed to predict triclosan antistaphylococcal activity in operated tissues. (3) Methods: Three TS were exposed to static water for 30 days, and triclosan release was recorded. Polyglactin TS explanted from sheep seven days after cardiac surgery according to 3Rs provided ex vivo acceleration benchmarks. TS immersion up to 7 days in ethanol-water cosolvency and stirring simulated tissue implantation. Controls were 30-day immersion in static water. The release rate over time was measured and fitted to a predictive function. Antistaphylococcal activity and duration were measured by time-kill analysis with pre-immersed polyglactin TS. (4) Fifteen to 60-fold accelerated in vitro conditions reproduced the benchmarks. The rate prediction with double-exponential decay was validated. The antistaphylococcal activity was bactericidal, with TS pre-immersed for less than 12 h before then S. aureus began to grow. The residual triclosan level was more than 95% and played no detectable role. (5) Conclusions: Polyglactin, poliglecaprone, and polydioxanone TS share similar triclosan release functions with parametric differences. Polyglactin TS is antistaphylococcal in surgical conditions for 4 to 12 h.

Do Different Sutures with Triclosan Have Different Antimicrobial Activities? A Pharmacodynamic Approach

“…V, P, M and triclosan-resistant P. aeruginosa were the controls. The experimental settings were the same as those used in static water release kinetics [ 26 ].…”

“…Therefore, its dissolution rate is slow around the suture, whose volume is 0.3 to 0.4% of the culture volume. Therefore, unless the tube is shaken, the triclosan diffusion layer forms a gradient with a maximum close to 10 µg/mL at the suture surface, decreasing with the distance from the source [ 7 , 26 , 36 , 37 , 38 , 39 ].…”

“…The culture conditions in static TSB (water + 3% organic nutrients and minerals) were closer to pure static water release kinetic determinations than to the ethanol/water 3.3% w/w solution with 24 rounds-per-minute constant rotation [ 26 ]. The triclosan release in 10 mL of pure static water is with V+ 2.3, 3.3 and 6.8 µg at 4, 8 and 24 h, respectively, with P+, 5.3, 6.7 and 6.1 µg and with M+, 7.6, 9.6 and 7.4 µg [ 26 ].…”

“…A previous study analysed the triclosan release kinetics of V+, P+ and M+ in pure static water and accelerated conditions calibrated to reproduce subcutaneous and intramuscular release in operated large animals [ 26 ]. It established the relation between the triclosan release rate and the antistaphylococcal activity in V+.…”

Do Triclosan Sutures Modify the Microbial Diversity of Surgical Site Infections? A Systematic Review and Meta-Analysis

“…Triclosan is a broad-spectrum antimicrobial, and in vitro and animal studies have shown that it inhibits microbial colonisation in TSs [ 16 , 17 , 18 , 19 , 20 , 21 ]. Once implanted, TSs are estimated to display biocidal-level antistaphylococcal activity during the first 4 to 12 h [ 22 ]. Therefore, TSs potentially reduce SSI development through the early decrease in bacterial load at the suture surface and the inhibition of suture colonisation.…”