Antimicrobial effects of plasma-mediated bipolar radiofrequency ablation on bacteria and fungi relevant for wound infection.

Infection constitutes an important part of wound pathology and impedes wound healing. Plasma-mediated bipolar radiofrequency ablation (Coblation(®)) is a tissue-removal technique suggested for use in wound treatment. The aims of this study were to determine the antimicrobial effect of ablation exposure on bacteria and fungi relevant to wound infection, and how exposure time, temperature and aerobic/anaerobic growth influence the effect. Suspensions of 10(6) colony-forming units/ml of Staphylococcus aureus, Streptococcus pyogenes, Pseudomonas aeruginosa, Escherichia coli and Candida albicans were exposed to ablation or thermal control for 500, 1000 or 2000 ms, or left untreated, and incubated aerobically. E. coli was also incubated anaerobically. Ablation was significantly (p < 0.0001) microbicidal on all strains compared with untreated and thermal control. The reductions compared with untreated control were 99.87-99.99% for all strains. In conclusion, plasma-mediated bipolar radio-frequency ablation has a general microbicidal effect in vitro on microbes relevant to wound infection independent of aerobic/anaerobic growth and thermal effect.