To the Editor:—

As new products are introduced, novel potential problems may be noted. 1My hospital system recently changed intravenous tubing systems to a set with valve ports (Smart Site; Alaris Medical Systems, San Diego, CA). These sets have female luer lock valve ports and comply with needle-free protocols. I find that the intravenous valve ports (especially when filled with propofol) are similar in appearance to the female luer lock connector and tubing of our blood pressure cuffs (Classic Cuf 2103; Critikon, Tampa, FL;fig. 1). Indeed, the noninvasive blood pressure inflation hose can be connected directly into the intravenous port (fig. 2). Activating our noninvasive blood pressure monitor (Spacelabs Medical 90426, Redmond, WA) in this case would deliver approximately 900 ml of air over 30 s intravenously, potentially causing serious injury or death.

Luer connectors, originally designed for attaching a syringe to a needle, have become a standard for parenteral systems. Because of the simple, effective design and added locking feature, it has been adopted for use in enteral, respiratory, epidural, intrathecal, and other miscellaneous systems as well. When syringes or tubings from different systems are misconnected, patient injury may result. A Spacelabs Medical safety alert 2warned that:

…[A] hazardous situation results from connecting the air tubing from a Spacelabs Medical NIBP monitor to a vascular access, such as an in-place patient IV. If air pressure is delivered to the patient during such a connection, it can cause serious injury or death. Spacelabs has received four reports of such incidents, one of which resulted in a patient's death…. We recommend that any blood pressure cuff using a luer connector fitting be placed on a different limb than the IV needle…. Warning labels will be sent for you to place on your NIBP monitors and hoses…. Use extreme caution when connecting the monitoring hoses to a blood pressure cuff that has a luer fitting.

There are Food and Drug Administration Manufacturer and User Facility Device Experience reports that mention misconnection of Spacelabs Medical noninvasive blood pressure inflation hose to intravenous connectors. 3 

Other misconnection injuries have been reported. Recent deaths have been caused by epidural local anesthetics given intravenously, 4intravenous chemotherapeutics given intrathecally, 5and enteral feedings given intravenously. 6A European Committee for Standardization Health Care Forum Focus Task Group 7recommended that luer connectors should be used only with syringes and devices connected to the vascular system, and that two new incompatible connectors be designed for the enteral and respiratory routes. Cyna et al.  8proposed an alternative incompatible connector specifically designed for epidural and intrathecal use. It may take time before changes like these are adopted and a new standard established.

I would recommend that one avoid luer connectors on blood pressure cuffs. A well-designed system should not allow a single error to result in such a catastrophe. There are a multitude of alternate connectors and adaptors available for blood pressure cuffs.

Stone B, Leon B: Unusual cause of intravenous catheter obstruction. A nesthesiology 1998; 89: 276–7
Spacelabs Medical urgent product safety alert, Spacelabs Medical non-invasive blood pressure monitors; October 29, 2001
Food and Drug Administration Manufacturer and User Facility Device Experience report No. 3023361-2001-0001, 3023361-2001-0002, 352904
Spasted D: Patient died after being injected with wrong fluid. Electronic Telegraph, London; May 2, 2001
Laville S, Hall C, McIlroy A: Cancer boy dies after doctors’ drug blunder. Electronic Telegraph, London; February 3, 2001
Food and Drug Administration Manufacturer and User Facility Device Experience report No. 9616066-1999-00012
European Committee for Standardization Health Care Forum Focus Task Group: Luer connectors CR 13825; 2000
Cyna A, Simmons S, Osborn K, Andrew M: Fatal epidural infusion: Call for a system wide change. Anaesth Intensive Care 2001; 29: 670–1