Mobile phones safe in hospitals
4 April 2007
A study by the Mayo Clinic in Rochester, USA, of mobile phone use in
hospitals has found that they have no noticeable effect on medical devices
in normal use. This dispels the long-held notion that they are unsafe to use
in health care facilities, according to the researchers.
In other reports, however, a CD player and a shop anti-theft device have
caused adverse effects on an ECG recording and pacemaker, respectively — the
latter with the potential to be life-threatening.
In the mobile phone study, which was published in the March issue of
Mayo Clinic Proceedings, three hundred tests were performed over a
five-month period in 2006, without a single problem incurred.
The study involved two mobile phones using different technologies from
different carriers and 192 medical devices. Tests were performed at Mayo
Clinic campus in Rochester, USA.
The study’s authors say the findings should prompt hospitals to alter or
abandon their bans on cell phone use. Mayo Clinic leaders are reviewing the
facility’s cell phone ban because of the study’s findings, says David Hayes,
M.D., of the Division of Cardiovascular Diseases and a study author.
Cell phone bans inconvenience patients and their families who must exit
hospitals to place calls, the study’s authors say.
The latest study revisits two earlier studies that were done ‘in vitro’
(ie, the equipment wasn’t connected to the patients), which also found
minimal interaction from cell phones used in healthcare facilities. Dr.
Hayes says the latest study bolsters the notion that cells phones are safe
to use in hospitals.
Other technology-related effects
Two other articles in the March issue of Mayo Clinic Proceedings
also address whether technological devices interfere with patient care
equipment. Unlike the mobile phone study, the other reports detail
technological devices that caused patient care equipment to malfunction.
A letter to the editor published in the journal details the first known
case of a portable CD player causing an abnormal electrocardiographic (ECG)
recording within a hospital setting. The recording returned to normal when
the CD player, which the patient was holding close to the ECG lead, was
Technology also can threaten implantable rhythm devices such as
pacemakers and defibrillators outside the hospital setting, according to a
journal report. The report outlines two cases of retail stores’ anti-theft
devices causing people’s heart devices to malfunction.
The anti-theft devices are commonly placed near store exits and
entrances, triggering an alarm if customers leave with merchandise that was
not purchased. In two instances in Tennessee, customers with a pacemaker and
an implantable cardiac defibrillator experienced adverse reactions after
nearing anti-theft devices.
The devices triggered the adverse reactions, sending both patients to
emergency rooms for evaluation. The report’s authors recommend that the
anti-theft devices be placed in areas of stores where customers won’t linger
— away from vending machines or displays of sale merchandise, for instance —
to help avoid future episodes.
Store employees also should be trained to move a customer who has
collapsed near an anti-theft device when medically advisable, says J. Rod
Gimbel, M.D, of East Tennessee Heart Consultants, and an author of the
report. If they aren’t moved, they could experience recurring
life-threatening malfunction to their implantable device, as did one patient
who was described in the report.
“Simply moving the person away from the anti-theft device may save their
life,” Dr. Gimbel says.
Though Gimbel’s report outlines only two cases of anti-theft devices
causing implantable heart devices to malfunction, he asserts that similar
instances are likely underreported, qualifying the problem as a potentially
widespread public safety issue.
“Many times with public safety issues we wait until something bad occurs
before we act,” Dr. Gimbel says. “Here’s an opportunity where we can make
our knowledge public and head off future problems.”
In an accompanying editorial, John Abenstein, M.D., of Mayo Clinic’s
Department of Anesthesiology, addresses the journal reports relating to the
impact of technological devices on patient care equipment.
Dr. Abenstein says the risk of some technological devices upsetting the
function of patient care equipment in hospitals appears to be small. The
Food and Drug Administration (FDA) should take a more explicit stand on the
matter, he says, so that health care facility policies can be altered when
Articles are available online at