AAMI Committee Explores Interaction Between EAS Gates, Medical Devices

With a growing number of patients receiving implantable electronic medical devices, there is increased concern about their exposure to electronic article surveillance (EAS) gates, which are designed to deter shoplifting. The Association for the Advancement of Medical Instrumentation (AAMI)’s Cardiac Rhythm Management Device Committee recently met to discuss the potential risks patients face when they are exposed to these surveillance systems.

Experts have voiced concern about the interaction between medical devices and EAS systems for more than a decade, and there have been examples of patients experiencing shocks and other adverse events. According to data from the U.S. Food and Drug Administration’s (FDA) Manufacturer and User Facility Device Experience (MAUDE) database, most adverse events have occurred in patients with spinal cord neurostimulators. Still, events involving pacemakers and other implantable cardiac devices have been reported. A 71-year-old man with a defibrillator was shocked and staggered as he passed by an EAS system, and 76-year-old woman with a pacemaker collapsed while standing near a gate. She passed out several more times before store employees moved her away from the system, according to an article appearing in The New York Times March 13, 2007, citing a report in the Mayo Clinic Proceedings.

FDA has taken notice, issuing guidance in 2000, titled Labeling for Electronic Anti-Theft Systems and summarily referred to as “don’t lean and don’t linger.” The guidance recommends “that all manufacturers of electronic antitheft systems develop labeling or signage to post on or near all new and currently installed systems, indicating that an electronic antitheft system is in use.” Such precautions would alert patrons to the presence of these systems so those with implanted electronic medical devices could “avoid lingering around or leaning against” them.

At the meeting, committee members discussed whether this guidance was becoming ineffective. A primary concern of the committee, which is co-chaired by Bob Stevenson, senior scientist at Greatbatch Medical in Clarence, NY, and Roger Carrillo, MD, thoracic and cardiac surgeon at the University of Miami Hospital, was that many retailers are obfuscating EAS gates. Examples of how EAS gates may be hidden include the following:
• Advertisements and other signage, vending machines, coffee stations, and other attractive elements can cause individuals (including patients with medical devices) to potentially “linger and lean” near EAS gates.
• High-end retailers placing chairs and lounge-type furniture in close proximity to the gates.
• Under-the-floor EAS systems are becoming more prevalent. Because they are not visible, patients may not be aware of their presence.
• Signs alerting people of the presence of EAS gates typically are quite small-typically 3-by-5-inch-and can be easily hidden from view by advertisements or other objects.

To help gain insight into the topic, the committee heard the views of physicians, representatives from pacemaker manufacturers, and scientists who have performed extensive EAS gate testing. In addition, representatives from EAS systems manufacturers offered their perspectives.

As the discussions progressed, the members  agreed that walking through EAS gates at a normal pace may cause a pacemaker to drop a couple of beats or have an extra beat, but the patient is not likely to notice.  However, if such a patient lingered for several minutes in close proximity to an EAS gate, it could lead to a  very dangerous or even life-threatening situation. In addition, the group agreed that test data are needed on under-the-floor EAS systems. Initial tests have shown no interactions, but the data are preliminary.

Hubert Patterson, Tyco vice president and chief technology advisor at Sensormatic in Boca Raton, FL, provided an EAS manufacturer’s perspective. Patterson said Sensormatic takes the “don’t lean and don’t linger” guidance very seriously and has a policy of “zero harm.” He noted that electromagnetic field (EMF) levels for EAS gates have not changed in 20 years; that Sensormatic is not going to make larger, more powerful systems; and that it does not wish to raise EMF levels, but only maintain current ones.

Furthermore, Sensormatic is revamping its guidance to retailers to mitigate the risk of patients lingering around EAS gates, Patterson said. In addition to sending letters to retailers, the company is educating its front-line sales employees about the dangers of attractive factors that can increase the probability of customers lingering near EAS gates.

Complicating things is that Sensormatic provides its technology to antitheft system manufacturers. It then sells these systems to retailers; therefore, the company cannot contractually stipulate that EAS gates should be free from advertisements. As a result, enforcing best practices can prove problematic.

Mitchell Shein, branch chief for pacing and defibrillation devices at the FDA, recommended that industry conduct human factors testing to determine whether patients are able to determine whether EAS systems are in place, given a variety of factors (e.g., presence or lack of signage on or around gates). Such research, he said, could provide better data on the likelihood of customers/patients to “lean and linger.”

Source: AAMI