Before needleless connectors were introduced, the only option was to place a needle on the end of the IV administration set and insert this needle through the solid covering on the injection cap. Yes I am aware that this practice tells you how long I have been doing this!!
There were concerns about having a needle residing inside the injection cap for extended periods including breakage of the needle inside the catheter lumen, having the needle piston into or out of the injection cap, the risk of infection, and the risk of needlestick injury to healthcare workers. So this practice was limited to only short-term intermittent infusions, usually over 30-60 minutes. All continuous infusions were connected by a direct hub-to-hub luer locking mechanism.
The introduction of the needleless connectors eliminated the use of needles and the risk associated with them. But these connectors were designed for intermittent use. So why has it become common practice for their use in a continuous infusion?
The most common reason I have been given is avoid opening the catheter lumen when it is time to change the administration set. But, that reason does not stand up to the CDC guidelines stating that the needleless connector should be changed at the same interval as the administration set. So the lumen must be opened to change both the connector and set simultaneously. The presence of a needleless connector inside a continuous system allows for questionable practice of stopping the infusion when the patient wants to ambulate, or shower, or other activity. This means an increase in manipulation of the catheter hub, and a possible increased risk of contamination and infection. This issue is more applicable to hospitalized patients as most infusions in alternative settings are intermittent rather than continuous.
The needleless connector in a continuous infusion adds an unnecessary device (this means added costs); they are a known source of infection; and they do nothing to enhance or alter the fluid flow in any way. The connector was designed for the sole purpose of eliminating the needle and the risk of needlestick injury. So I see no reason for using them in a continuous infusion system. I know that many other professionals disagree with me on this, but we need evidence. The 2014 SHEA Compendium CLABSI chapter includes this practice as an unresolved issue stating, “No data are available regarding their use with continuous infusions.” So just like everything, we need more studies! I am hoping drawing attention to this issue will spur the interest of researchers.