Microbiologic contamination of a positive- and a neutral- displacement needleless intravenous access device in clinical use

Impact of needle-free connectors compared with 3-way stopcocks on catheter-related bloodstream infection rates: A meta-analysis

BACKGROUND

Needle-free connectors (NFCs) were introduced to eliminate the use of needles in intravascular catheters, and their newest generations were designed to improve patient safety and reduce catheter-related bloodstream infection (CRBSI) risks. The aim of this meta-analysis was to compare NFCs with 3-way stopcocks (3WSCs) and their effects on CRBSI rates.

METHODS

A meta-analysis was conducted using a research protocol consistent with the PRISMA statement for reporting meta-analyses. The Cochrane Database of Systematic Reviews and MEDLINE were searched for relevant randomized studies published from January 2000 to September 2018.

RESULTS

We identified and selected for the meta-analysis 8 studies comparing CRBSI rates (according to the Centers for Disease Control and Prevention's National Healthcare Safety Network definition) associated with NFCs utilizing negative-displacement, neutral-displacement, or positive-displacement devices with rates for 3WSCs. Relative risk was 0.53 with a 95% CI of 0.28 to 1.00, and the relative difference was -0.018 with a 95% CI of -0.039 to 0.004.

CONCLUSIONS

CRBSI risk was statistically higher for 3WSCs compared to NFCs.

Clinical impact of needle-free connector design: A systematic review of literature

The objective of this systematic review is to analyze types of needle-free connectors and open systems and their effects on central line–associated bloodstream infection rates and other adverse outcomes through a research protocol consistent with the Preferred Reporting Items for Systematic Reviews’ recommendations. MEDLINE and Cochrane databases of systematic reviews were searched for relevant comparative studies published from January 2000 to September 2017. Eighteen studies compared central line–associated bloodstream infection (according to the Centers for Disease Control and Prevention/National Healthcare Safety Network definition), internal microbial contamination, occlusions, phlebitis, and other outcomes associated with needle-free connectors with a positive displacement device, negative displacement device, neutral displacement device, or three-way stopcock. Ten studies reported central line–associated bloodstream infection rates, which were lower with positive displacement devices versus negative displacement devices/neutral displacement devices (one study) and with negative displacement devices versus three-way stopcocks (three studies), but varied with different positive displacement device and negative displacement device/neutral displacement device designs (four studies). Seven studies reported internal microbial contamination rates, which were higher with three-way stopcocks versus negative displacement devices (two studies) and positive displacement devices (two studies), lower when positive displacement devices were used versus neutral displacement devices (one study), and varied with different types of negative displacement device (one study). Central line–associated bloodstream infection rates and most other outcomes analyzed were statistically significantly higher with three-way stopcocks (open devices) versus positive displacement device, negative displacement devices, and neutral displacement devices, but varied among closed device designs.

The risk of microbial contamination associated with six different needle-free connectors

BACKGROUND

needle-free connectors are widely used in clinical practice. The aim of this study was to identify any differences between microbial ingress into six different connectors (three neutral-displacement, one negative-displacement and two anti-reflux connectors).

METHODS

each connector underwent a 7-day clinical simulation involving repeated microbial contamination of the connector's injection ports with Staphylococcus aureus followed by decontamination and then saline flushes through each connector. The simulation was designed to be a surrogate marker for the potential risk of contamination in clinical practice.

RESULTS

increasing numbers of S. aureus were detected in the flushes over the 7 days of sampling despite adherence to a rigorous decontamination programme. Significant differences in the number of S. aureus recovered from the saline flush of some types of connectors were also detected. Two different durations (5- and 15-second) of decontamination of the injection ports with 70% isopropyl alcohol (IPA) wipes were also investigated. There was no significant difference between the median number of S. aureus recovered in the saline flushes following a 5-second (165.5, 95% CI=93-260) or a 15-second decontamination regimen (75, 10-190).

CONCLUSIONS

The findings suggest that there may be differences in the risk of internal microbial contamination with different types of connectors and that even 15 seconds of decontamination may not fully eradicate microorganisms from the injection ports of some devices.