The study, which is published in the 24th June issue of the Journal of the American Medical Association, JAMA, is the work of co-author Dr Erik Jan van Lieshout of the Academic Medical Centre of the University of Amsterdam and colleagues.
RFID technology is now so cheap and small that it has many uses, such as in anti-theft devices in shops, ID cards for security and travel, and tracking of inventory ranging from large machines to a hospital sponge. Many hospitals now put RFID tags on patients.
According to the BBC, patients who are about to have surgery at the Heartlands Hospital in Birmingham, have an RFID band put on their wrist. This allows information and even a photo of the patient to be retrieved wirelessly and downloaded to a nearby handheld computer or PDA.
However, it would seem that on the one hand, while the idea of RFID is to improve patient safety and hospital efficiency, on the other hand, it could be undermining both.
Lieshout and colleagues said RFID caused interference with medical equipment in 34 of the 123 tests they performed.
According to a report by USA Today, Lieshout said medical equipment makers should now develop ways to protect their medical devices from radio frequency interference.
In an accompanying article, titled "Taming the Technology Beast", Donald Berwick, president and CEO of the Institute for Healthcare Improvement in Massachusetts, said more studies are needed to determine the true risk posed by RFID technology in hospitals.
For the study, because there is no published research on the effect of electromagnetic interference from RFID on medical devices, Lieshout and colleagues decided to assess and classify any incidents they found of such interference on critical care equipment.
They tested a total of 41 medical devices such as ventilators, syringe pumps, dialysis machines and pacemakers, in 17 different categories from 22 different manufacturers during May 2006. Obviously no patients were attached to the equipment during the tests, which were conducted at the Academic Medical Centre in the University of Amsterdam and followed an internationally recognized protocol.
The researchers used two types of RFID equipment, active and passive. Active RFID tags transmit information whereas the passive type of RFID has to be read by a special receiver.
Incidents of interference were classed into three types: hazardous, significant, or light.
The results showed that:
- In 123 tests (3 per medical device), RFID induced 34 incidents.
- Of these, 22 were classified as hazardous, 2 as significant, and 10 as light.
- The passive (868-MHz) RFID signal induced more incidents (26 incidents in 41 tests; 63 per cent) compared with the active (125-kHz) RFID signal (8 incidents in 41 tests; 20 per cent).
- The passive RFID signal interfered with 26 medical devices, including 8 that were also affected by the active RFID signal.
- The median distance between the RFID reader and the medical device in all incidents was 30 cm (total range was from 0.1 to 600 cm).
"In a controlled nonclinical setting, RFID induced potentially hazardous incidents in medical devices."
They recommded that:
" Implementation of RFID in the critical care environment should require on-site EMI [electromagnetic interference] tests and updates of international standards."
"Electromagnetic Interference From Radio Frequency Identification Inducing Potentially Hazardous Incidents in Critical Care Medical Equipment."
Remko van der Togt; Erik Jan van Lieshout; Reinout Hensbroek; E. Beinat; J. M. Binnekade; P. J. M. Bakker.
JAMA, 2008; 299(24): 2884-2890.
Vol. 299 No. 24, June 25, 2008
Click here for Abstract.
Sources: Journal abstract, BBC, USA Today.