Antimicrobial activity and skin permeation of iodine present in an iodine-impregnated surgical incise drape

Objectives
The antimicrobial efficacy of an iodine-impregnated incise drape against MRSA was evaluated in a skin model. The permeation of iodine from this drape into the skin was also assessed.
Methods
The antimicrobial efficacy was evaluated in ex vivo studies following application of the surgical incise drape for various times on the surface of donor skin which was inoculated with either 1x103 or 1x106 cfu MRSA/cm2 skin and mounted on Franz diffusion cells. In some experiments the MRSA inoculated skin was pre-incubated for 18 h at room temperature prior to applying the drape. Permeation of iodine into the skin using this model was also determined following application of the incise drape for 6 hours.
Results
The iodine-impregnated drape demonstrated antimicrobial activity compared with the non-use of drape. This reached significance when a high inoculum of MRSA was applied with no pre-incubation period and when a low inoculum of MRSA was applied with a pre-incubation period (P=0.002 and P=0.014, respectively). Furthermore, in experiments wherein a high inoculum of MRSA was applied with no pre-incubation period, the iodine-impregnated drape demonstrated superior antimicrobial activity compared with the use of a non-antimicrobial drape (P<0.001).. MIC and MBC concentrations of iodine were attained to 1500μm below the skin surface.
Conclusions
The iodine-impregnated surgical incise drape had detectable antimicrobial activity. Furthermore, iodine penetrated into the deeper layers of the skin. This property should suppress microbial re-growth at and around a surgical incision site, making its use preferable to the use of a standard drape or non-use of drape.