Manual environmental disinfection with hydrogen peroxide and silver ions versus sodium hypochlorite in operating rooms: a multi-centre randomized trial on residual antimicrobial efficacy.

BACKGROUND

Environmental surface contamination in operating rooms (ORs) plays a role in pathogen transmission associated with surgical-site infections. Although sodium hypochlorite is commonly used for environmental disinfection, its lack of residual antimicrobial activity may allow rapid surface recontamination. This study compared the immediate and residual antimicrobial efficacy of a hydrogen peroxide-silver ion formulation with sodium hypochlorite on high-touch OR surfaces.

METHODS

In this multi-centre randomized experimental study, 24 ORs across three tertiary hospitals were assigned to disinfection with either hydrogen peroxide (2%) stabilized with silver ions (10 ppm) or sodium hypochlorite (0.5%). A total of 480 samples were collected from five high-touch surfaces at baseline, immediately after disinfection, and 2 and 4 h post disinfection. Microbial loads and recontamination rates were statistically compared.

RESULTS

Baseline microbial loads were similar between groups (P = 0.115), and both disinfectants achieved complete immediate bacterial reduction. At 4 h post disinfection, sodium hypochlorite-treated surfaces showed substantial recontamination (60.0%; median: 20.0 cfu/mL), whereas hydrogen peroxide-silver ion-treated surfaces demonstrated sustained antimicrobial suppression (8.3%; median: 0.00 cfu/mL; P < 0.001). Pseudomonas aeruginosa regrowth was observed only in the sodium hypochlorite group.

CONCLUSIONS

Despite comparable immediate antimicrobial effects, sodium hypochlorite lacked residual activity, permitting rapid surface recontamination. The hydrogen peroxide-silver ion formulation provided superior residual antimicrobial efficacy over four hours, supporting its potential use in infection prevention during prolonged surgical procedures.