Radio-Wave Devices May Play Havoc With Medical Equipment
In lab setting, they caused some machines to turn off, others to malfunction
TUESDAY, June 24, 2008 (HealthDay News) -- Those magic little devices that allow you to enter your hotel room or pay a toll electronically could interfere with the operation of critical medical equipment in a hospital.
In a laboratory setting not involving actual patients, Dutch scientists found that the radio frequency identification devices -- which are increasingly used in medicine -- caused potentially hazardous problems with some medical tools.
The findings were published in the June 25 issue of the Journal of the American Medical Association.
However, the scope of the danger is not yet clear.
"This leaves us concerned, [but] we have to see if this pans out in a real intensive care unit," said Dr. Donald M. Berwick, president and CEO of the Institute for Healthcare Improvement in Cambridge, Mass., and author of an accompanying editorial. "These [devices] are brought in for a reason, and are doing things for the good. Just to shut them down would be overreacting. Let's get serious about finding out whether this is a replicable finding, and if it occurs in the presence of real patients. I believe food and drug administrations and manufacturers have a duty to investigate, and I'd say urgently."
The use of these devices is increasing in medical settings. For example, in respirators or IV pumps they help locate and keep track of inventory; they could also be used in drug blister packs to prevent counterfeiting or to ensure the quality of blood products.
"They're so tiny now that they can be put in surgical gauze pads, so at the end of the operation, the nurse can count up all pads and notice if one is missing and might have been left in the patient," Berwick said. "There are all sorts of applications in hospitals, and the devices are proliferating."
But there might be a dangerous downside to such sophisticated technology.
This study took place in a simulated, one-bed intensive-care unit at the University of Amsterdam in the Netherlands. There were no patients involved, but there were 41 medical devices typically used in such a setting such as respirator machines, IV pumps, dialysis devices, defibrillators and external pacemaker devices.
Two radio frequency identification device systems, one active (with a battery and able to transmit information continuously) and one passive (powered by the electromagnetic field of the reader) were moved around the room while researchers assessed electromagnetic interference (EMI) on the medical devices.
In all, researchers conducted 123 EMI tests, and 34 EMI incidents were recorded: 22 were considered hazardous (for example, the turn-off of a mechanical ventilator or malfunction of external pacemakers), two as significant (an inaccurate blood pressure reading or alarm wrongly going off which might divert attention from the patient), and 10 as light ("snow" on the monitor, which didn't need attention).
The passive signal resulted in a higher number of total incidents (26 out of 41, or 63 percent), as well as more hazardous incidents (17).
All incidents occurred at a median distance of 11.8 inches between reader and device. For hazardous incidents, the median distance was 9.8 inches.
"This ought to teach us a lesson about technologies in medicine in general," Berwick said. "Anything new is going to introduce both good news and bad news. There will always be consequences. We have a love affair with technology, and that's a little bit dangerous if we're not keeping our eyes wide open. This is a good heads up."
Visit the U.S. Department of Health and Human Services for more on health-care technology.