In Vitro Evaluation of Common Antimicrobial Solutions Used for Breast Implant Soaking and Breast Pocket Irrigation-Part 2: Efficacy Against Biofilm-Associated Bacteria.

backgroundBiofilm-associated bacteria have been observed in both breast implant revision and tissue expander-implant exchange surgeries. The utilization of antimicrobial solutions in breast surgery, especially those containing triple antibiotics (TAB) and/or 10% povidone-iodine (PI), may help reduce existing biofilm-associated bacteria, which is particularly important in a mature breast pocket that may contain residual bacteria from a previously colonized implant surface or, theoretically, bacteria that may arrive postoperatively through hematogenous spread.

objectivesA series of in vitro assessments was performed to evaluate the antimicrobial utility of TAB and PI, either alone or in combination, against preformed biofilm-associated bacteria.

methodsPreformed biofilm-associated gram-positive and gram-negative bacterial strains were exposed to TAB and PI ± TAB for up to 30 minutes in a bacterial time-kill assay. Efficacy of various dilutions of PI and the effects of serum protein on PI efficacy were also investigated.

resultsTAB was ineffective at the timeframes tested when utilized alone; when utilized in conjunction with PI, significant log reduction of all biofilm-associated bacterial species tested was achieved when treated for at least 5 minutes. PI alone at a concentration of 25% or higher was also effective, although its efficacy was negatively affected by increasing serum protein concentration only for Staphylococcus epidermidis.

conclusionsOur data indicate that PI-containing solutions significantly reduce biofilm-associated bacteria, suggesting potential utility for breast pocket irrigation during revision or exchange surgeries. Care should be taken to minimize excessive dilution of PI to maintain efficacy.