Do Needleless Connector Manufacturer Claims on Bidirectional Flow and Reflux Equate to In Vitro Quantification of Fluid Movement?
Background: Manufacturers designed needleless connectors (NCs) to reduce needlestick injuries and exposures to bloodborne pathogens. All NCs displace fluid, and most do not control fluid movement through the device. The observed bidirectional fluid movement and reflux may not be consistent with how the manufacturer of the device describes NC. Reflux may lead to a significant patient safety risk as it relates to intraluminal thrombotic occlusion and infection.
Methods: The in vitro observational study 1 (OS1) systematically tested bidirectional flow control; the ability prevented retrograde fluid from flowing into the infusion system. Researchers tested 13 commonly used NCs. The observational study 2 (OS2) measured the amount of displaced fluid in each NC paired grouping during connection and disconnection of a Luer locking device.
Results: OS1: Eleven NCs failed bidirectional flow control, and 2 passed bidirectional flow control. OS2: All 13 NCs had varying amounts of fluid displacement or reflux. The measured volume of reflux for NCs during disconnection was 0.17 μL to 114.65 μL. The measured volume of reflux for NCs during connection was 11.73 μL to 34.43 μL.
Conclusion: NC labeling does not appear to correspond with manufacturer claims. Neutral displacement does not appear to be present in the NCs used in this observational study. To properly instruct health care professionals about using the various NCs available, it is imperative to know the accurate bidirectional control, reflux cycle, and volume of reflux beyond the manufacturer’s performance claims. Precise information may assist the clinician in reducing intraluminal blood exposure of vascular access devices.Abstract

Procedure for observational study 1.

Procedure for observational study 2.

Results of observational study 2. This chart shows when reflux occurs (i.e., connection or disconnection) and how much blood reflux would occur in a closed intravenous (IV) system upon unclamped connection and disconnection of a male Luer lock syringe or IV administration set.
Contributor Notes