Luer connectors were invented in the late 1890s to provide leak-free connections between glass hypodermic syringes and needles, while allowing easy fitting and removal by pushing together and pulling apart (“Luer slip”). Several years later, a variant was made with threads so that the connectors would be screwed together and secured (“Luer-lock”).
Luer fittings became the standard for intravenous use, and then became popular for many other uses requiring small-bore connectors, from attaching blood pressure cuffs to inflation sources to connecting epidural catheters to anesthetic infusions. With so many different applications using the same connector, accidental cross-connections, some fatal, began to appear.
A 24-year-old woman was 35 weeks pregnant when she was hospitalized for vomiting and dehydration. A bag of ready-to-hang enteral feeding was brought to the ward, and the nurse, assuming it was total parenteral nutrition that the woman had received on previous admissions, pulled regular intravenous tubing from the floor stock, spiked the bag, and started the infusion of tube feeding through the patient’s peripherally inserted central catheter (PICC) line. Both mother and fetus died.
The risk of deadly cross connections like this can be significantly reduced by adopting physically incompatible connectors for different uses. For example, if the enteral feeding system were attached to an administration set with a connector incompatible with a Luer intravenous fitting, then the care giver would be unable to accidentally connect the enteral feeding administration set to the intravenous line.
Until now, there has been no standard for non-Luer fittings to accomplish this objective. Hospitals wishing to institute mechanical barriers to cross connections have been faced with the challenges that proprietary connectors pose—such as introducing new cross-connection risks and device incompatibilities between institutions.
Soon there will be international standards for specialized connectors specific to neuraxial (e.g., epidural and intrathecal), blood pressure cuff, urinary, enteral and breathing/ventilator systems; each mechanically protected from connecting with the other. These connectors will also be protected from connecting with Luer fittings, which will continue to be used for intravascular and hypodermic applications.
This international standards initiative is led by the International Organization for Standardization [ISO] committee. CHPSO is a member of the USA section of the ISO standards committee and is involved in planning the transition from the current set of connectors. Manufacturers are striving to meet California’s January 2016 deadline mandating physical barriers to cross connections between enteral, neuraxial and intravascular applications.
Phased introduction plan for each class of connectors. Each phase in this plan lasts six months.
New challenges will arise during the transition period from universal use of Luer connectors to non-Luer connectors for specific uses. For example, when the UK instituted non-Luer connectors for neuraxial uses, a hospital in Wales received a shipment of the new, non-Luer spinal needles before it was expected. This only came to light when an obstetric patient had the spinal needle inserted, the clinician went to connect the syringe of medication, and found that the two would not connect. The needle was removed, a Luer spinal needle found, and the procedure repeated.
Plans are being made that satisfy the following goals:
Assure clinician usability comparable to current Luer devices
Generate awareness of the reason for and the introduction of global standards
Facilitate rapid adoption of new global standard small-bore connectors
Integrate the new connectors with minimal disruption to the supply chain and clinical practice
Develop and execute timeline delivering focused messaging, programs and measures for success
Manage specific messaging for respiratory, enteral, and limb cuff, neuraxial, and intravascular/hypodermic suppliers (as well as possible future applications) launching the new international small-bore connectors
To avoid some of the compatibility challenges experienced by the UK, for each new connector that is released, all manufacturers will simultaneously change from Luer to non-Luer connectors in order to “flush out” the legacy devices from the supply chain. During the transition period for enteral devices, each enteral administration set will include an adapter to ensure that legacy feeding tube compatibility issues are obviated. Practitioners should be aware that, during the transition period for enteral devices, the presence of these adapters will allow cross connections, and the provided adapters should only be used after double checking the two items being connected.
The new connectors will be launched in sequence, starting with the enteral connectors, then probably neuraxial, with the others to follow. The current plan is to wait six months between each launch; however, the timeline may be contracted to assure meeting the January 2016 deadline. CHPSO is working with manufacturers to help meet this deadline.
Sample for neuraxial use. Neuraxial male connectors will have a tip diameter about 20% smaller than Luer male connectors. Two variations of these connectors: “lock” type with threads (pictured), typically for longer term use such as epidural infusions, and “slip” type, frequently used in procedures such as lumbar puncture. For neuraxial, all male connectors will have a collar as pictured, which helps prevent cross-connection with the larger caliber female Luer intravenous connector.