Reducing the risk of infection in vascular access patients: an in vitro evaluation of an antimicrobial silver nanotechnology luer activated device.

Background: Luer-activated devices (LAD) have been designed to reduce the risk of sharps injury; however, published reports suggest that internal fluid path contamination occurs in selected devices. The present in vitro study compares the antimicrobial property of a silver-nanotechnology LAD to 8 nonantimicrobial LADs.

Methods: A laboratory reference strain of methicillin-resistant Staphylococcus aureus (MRSA) (ATCC 33592) was used to prepare a standardized microbial challenge, 3.73- to 3.86-log(10) colony-forming units (cfu)/mL, adjusted for fluid path volume for 9 commercially available LAD (1 sliver nanotechnology LAD and 8 non-antimicrobial LADs). Following incubation (15 hours at 30 degrees C), each device was flushed, serially diluted, and plated in triplicate to trypticase soy agar for microbial recovery, expressed as log(10) cfu/mL.

Results: Comparison of fluid path volumes documented a wide variation between the 9 commercial devices (range, 0.025-0.359 mL). Log(10) microbial recovery were shown to increase on average 1.5 to 3.0 logs in the 8 non-antimicrobial LADs, whereas S aureus recovery in the silver-nanoparticle LAD demonstrated a 2.6-log decrease following incubation (P < or = .05).

Conclusion: These findings suggest that, under in vitro conditions, a silver nanotechnology was effective in reducing the risk of fluid path colonization when the LAD was challenged using a standardized inoculum of a laboratory reference strain of MRSA. Further studies are warranted to assess the clinical efficacy of an antimicrobial LAD technology for reducing the risk of vascular access (catheter associated) infections.