Mitigating interference between electronic medical devices

By John Halamka

Last week, JAMA published an article about the risks of active and passive radio frequency identification  to other hospital equipment.

The Associated Press and ABC News issued major stories about it.

Although the study focused on RFID tags, the issue is more generic. Electronic Magnetic Interference (EMI) is generated by many devices including cell phones, laptops, and microwave ovens. Such devices emit RF energy which may interfere with the operation of sensitive electronic components used in medical equipment. The interference may be frequency related (signal jamming) or cause the device to fail because a chip or wire is exposed to too much energy from an emitting device. The very best defense is to have adequate shielding for medical equipment. It's inconceivable that hospitals can keep patient care areas free of RF emitters. Thus, it is important for hospital clinical engineering departments to be  vigilant in identifying potentially unsafe devices.

CareGroup addressed this issue 7 years ago with a global EMI guideline and summary, which we developed by inviting 100 industry experts and the FDA to a consensus conference in Boston.

Of course, we continue to test new EMI emitting technologies as they are introduced into the hospital. Our RFID use is well documented. The Active RFID tags deployed at BIDMC have been tested by Clinical Engineering for interference with other hospital devices and do not cause a problem.

In addition to thinking about the risks of new technologies, we should also consider the benefits. Remember that every activity in life has a risk (which I measure in Morts). If the risk of patient harm is 1 in a million, but the benefit of using the technology prevents harm to every patient, the hospital needs to carefully assess the balance. In the case of RFID, we have deployed the technology with significant testing and adherence to our guidelines, mitigating the risks and maximizing the benefits.

John D. Halamka, MD, MS, is Chief Information Officer of the CareGroup Health System, Chief Information Officer and Dean for Technology at Harvard Medical School, Chairman of the New England Health Electronic Data Interchange Network (NEHEN), CEO of MA-SHARE (the Regional Health Information Organization), Chair of the US Healthcare Information Technology Standards Panel (HITSP), and a practicing emergency physician. He blogs regularly at Geekdoctor.