Does adding hydrogen peroxide to chlorhexidine gluconate increase the effectiveness of skin preparation in reducing cutaneous Cutibacterium levels? A randomized controlled trial

Background: Shoulder periprosthetic joint infection is most commonly caused by Cutibacterium. Effective removal of these bacteria from the skin is difficult because Cutibacterium live protected in the dermal sebaceous glands beneath the skin surface to which surgical preparation solutions, such as chlorhexidine gluconate (CHG), are applied. There is conflicting evidence on the additional benefit of using hydrogen peroxide (H2O2) as an adjunct to CHG in eliminating Cutibacterium from the skin. A previous study demonstrated that after CHG skin preparation, repopulation of Cutibacterium from sebaceous glands onto the skin surface occurs in 90% of shoulders by 60 minutes after application. The objective of this randomized controlled study was to determine the effectiveness of adding H2O2 to CHG in reducing skin Cutibacterium. Methods: Eighteen male volunteers (36 shoulders) were recruited for this study. The 2 shoulders of each volunteer were randomized to receive the control preparation ("CHG-only"- 2% CHG in 70% isopropyl alcohol alone) or the study preparation ("H2O2+CHG"- 3% H2O2 followed by 2% CHG in 70% isopropyl alcohol). Skin swabs were taken from each shoulder prior to skin preparation and again at 60 minutes after preparation. Swabs were cultured for Cutibacterium and observed for 14 days. Cutibacterium skin load was reported using a semiquantitative system based on the number of quadrants growing on the culture plate. Results: Prior to skin preparation, 100% of the CHG-only shoulders and 100% of the H2O2+CHG shoulders had positive skin surface cultures for Cutibacterium. Repopulation of Cutibacterium on the skin at 60 minutes occurred in 78% of CHG-only and 78% of H2O2+CHG shoulders (P = 1.00). Reduction of Cutibacterium skin levels occurred in 56% of CHG-only and 61% of H2O2+CHG shoulders (P = .735). Cutibacterium levels were significantly decreased from before skin preparation to 60 minutes after preparation in both the CHG-only (2.1 +/- 0.8 to 1.3 +/- 0.9, P = .003) and the H2O2+CHG groups (2.2 +/- 0.7 to 1.4 +/- 0.9, P <.001). Substantial skin surface levels of Cutibacterium were present at 60 minutes after both preparations. Conclusions: In this randomized controlled study, there was no additional benefit of using hydrogen peroxide as an adjunct to chlorhexidine gluconate skin preparation in the reduction of cutaneous Cutibacterium levels. Neither preparation was able to eliminate repopulation of Cutibacterium on the skin surface from the dermal sebaceous glands.