Research from a joint US-Chile clinical trial studying the contribution of antimicrobial copper touch surfaces to environmental hygiene in a paediatric intensive care unit describes the intervention as a ‘no-touch disinfection technology’ that warrants serious consideration as part of a bundle of infection prevention measures.1
While acknowledging that the hospital environment is a significant reservoir of microbes that can cause infections, the researchers observe that although cleaning, hand hygiene and other measures are effective, they cannot completely eliminate contamination risk. Active antimicrobial copper surfaces offer an additional hygiene measure.
The new study — conducted at Roberto del Rio Children’s Hospital in Chile — aimed to build on the evidence that copper and copper alloy surfaces decrease the burden of micro-organisms in healthcare environments, and assess whether this reduced the risk of healthcare-associated infections (HCAIs) in paediatric intensive and intermediate care units, as has been reported in adult ICUs.
Admitted infants were assigned sequentially to a room, eight with standard surfaces and eight where key touch surfaces had been replaced with antimicrobial copper items: bed rails, bed rail levers, IV poles, tap handles and the nurses’ workstation. Infection data were collected on a daily basis for the 12-month duration of the study, with HCAIs confirmed according to protocol definitions.
The copper surfaces were found to harbour, on average, 88% fewer bacteria than those in the control rooms, and 94% met the bacterial concentration limit for terminal cleaning (<500 cfu per 100cm2), compared with only 48% of controls.2
Copper interventions should be considered as part of a systems-based approach to controlling HCAIs
For the second part of the study, clinical outcomes from 515 patients were considered in the analysis: 261 patients from the intervention arm of the study, and 254 from the control arm. Crude analysis showed an HCAI rate of 10.6 compared with 13.0 per 1,000 patient days for copper- and non-copper-exposed patients, respectively, for a crude relative risk reduction of 19%.
The researchers concluded that exposure of paediatric patients to solid antimicrobial copper objects in the ICU resulted in decreased HCAI rates when compared with those in non-copper surroundings. They note that the relative risk reduction was not statistically significant, and report that certain events such as overcrowding may have limited the antimicrobial contribution provided by the copper intervention.
The authors also said that designing a randomised control trial was challenging. Nonetheless, they believe copper interventions should be considered as part of a systems-based approach to controlling HCAIs.
‘In contrast to the US trial — where copper surfaces were found to significantly reduce HCAIs in an adult study population from 11.8 to 4.8 per 1,000 patient days (p= 0.013) — the study here represents the first evaluation of the utility of antimicrobial copper for reducing HCAIs in a paediatric setting,’ explained co-author Dr Michael Schmidt, Professor and Vice Chair of Microbiology and Immunology at the Medical University of South Carolina.
‘Given the additional complications of conducting the trial in a paediatric setting, in concert with multiple patients housed in the same room, the result that copper was able to reduce the HCAI rate from 13.0 to 10.6 per 1,000 patient-days is very promising, providing additional support for the general conclusion that the no-touch disinfection solution provided by antimicrobial copper surfaces offers an answer to the omnipresent risk manifested by microbes within the built clinical environment.’
References
1. Potential effectiveness of copper surfaces in reducing health care–associated infection rates in a pediatric intensive and intermediate care unit: A nonrandomized controlled trial. Bettina von Dessauer Maria S. Navarrete, Dona Benadof, Carmen Benavente, Michael G. Schmidt. American Journal of Infection Control. doi:10.1016/j.ajic.2016.03.053.
2. Copper Surfaces are Associated with Significantly Lower Concentrations of Bacteria on Selected Surfaces within a Pediatric Intensive Care Unit. Michael G. Schmidt PhD; Bettina von Dessauer MD; Carmen Benavente MD; Dona Benadof MD; Paulina Cifuentes RN; Alicia Elgueta RN; Claudia Duran MS; Maria S. Navarrete MD MPH. American Journal of Infection Control, Corrected proof. doi:10.1016/j.ajic.2015.09.