Abstract
Aim
The purpose of this study was to compare the presence of P.acnes on the skin after topical pre-operative application with benzoyl peroxide (BPO) to chlorhexidine soap (CHS) and whether this also affected skin recolonization after surgical preparation and draping.
Method
Forty volunteers – twenty-four men and sixteen women were randomized to pre-operative topical treatment at home with either CHS or BPO in the area of a delto-pectoral approach of their left shoulder. The right served as a control. Five skin swabs were taken in a standardized manner on different occasions: before and after topical treatment, after surgical skin preparation and sterile draping and 120 minutes after draping. A fifth sample was taken on the contralateral untreated side as a control when the patient was draped. The draping took place in an operating room with laminar air flow and skin preparation was performed for 2 minutes with 0.5% chlorhexidine solution in 70% ethanol according to the recommendations of the Swedish National Board of Health and Welfare.
Bacterial colonies were then analyzed on agar plates by colony forming units (CFU) and surface characteristics. P.acnes were identified with matrix-assisted laser desorption/ionization time-of-flight (MALDI-ToF) mass spectrometry.
Results
Topical treatment with BPO significantly reduced the presence of P.acnes as CFU on the skin after surgical preparation. P.acnes was found in 1/20 subjects of the BPO group, and 7/20 in the CHS-group (p<0.044). The results remained after two hours (p<0.048). Topical treatment with BPO before surgical skin preparation significantly decreased the presence of CFU (p-value 0.035).
Conclusions
Topical preparation with BPO before shoulder surgery may be effective in reducing P.acnes on the skin and prevent recolonization.
