Concordia: A Concordia study examines whether wireless transmitters represent a danger to patients. Thousands of patients die each year in hospitals across North America
due to medical errors that could be prevented were doctors and nurses
provided with instant access to patient records via wireless technology.
Cue the Catch-22: the electromagnetic radiation caused by those very
devices can interfere with electronic medical equipment and thus lead to
serious clinical consequences for patients.
Luckily, that could soon change thanks to new research from Concordia
University that helps define a clear rule of thumb for how close
health-care workers with their Wi-Fi devices can be to electronic
medical equipment.
In a study published recently in IEEE Transactions on Electromagnetic Compatibility, researchers from the Faculty of Engineering and Computer Science
assessed the risk that a medical device will malfunction when radio
waves that emanate from portable devices like tablet computers are
present in a hospital room.
Hospitals often specify that staff members carrying wireless
transmitters not approach sensitive electronic medical devices any
closer than a designated minimum separation distance (MSD).
“We wanted to see whether this policy really affects the risk of electromagnetic interference,” says the study’s lead author Mehdi Ardavan,
who recently completed his PhD in Electrical Engineering. “But there
were two main obstacles: one was the high cost of determining and
computing the electromagnetic field strength; the second was the lack of
any study on how the medical staff carrying the wireless devices move
around a patient’s bed.”
So Ardavan and his colleagues combined existing methods to develop a
tool to estimate the likelihood that a particular field would affect a
given medical device. The researchers combined this method with a new
mathematical model to account for the roaming nature of the
transmitters, given that hospital staff are almost always on their feet.
“We found that MSD policy really does work. If hospital staff comply
fully with the policy, they can have a tablet in the same room as the
patient and medical equipment without posing a danger,” says Ardavan.
It’s only when hospital staff become lax with the rules that issues
occur. “We observed that the risk reduces rapidly by increasing the MSD
from zero to a small value. After that, the risk doesn’t decrease when
you increase the MSD beyond a level that we call the optimal MSD. This
indicates that specifying larger minimum separation distances doesn't
necessarily increase safety.”
For Christopher Trueman, senior author and professor in the Department of Electrical and Computer Engineering,
the message is clear. “Hospitals need to be vigilant that staff members
obey the MSD rule. The nature of the problem is that there can never be
zero risk, but by complying with MSD, the risk can be reduced to a low
enough value that it's very unlikely there will be interference.”
The bottom line: keep your wireless device further than arm’s length
from medical equipment and the risk of interference is very small.