Is There Interference in the Air?
December 2005
The exploding use of wireless technology in health care is a blessing for many clinicians and patients. Physicians and nurses can have instant access to patient information using a desktop computer on a mobile cart at the bedside, a Tablet PC, notebook PC or a PDA.
Bored patients can have access to the Internet via their own notebook PCs or PDAs to surf the Web, e-mail family and friends, or even work from bed.
But all the radio waves moving through a facility-from computing devices, mobile phones, pagers, two-way radios and other devices-can interfere with the integrity of clinical data being accessed or transmitted via a wireless network. They also can interfere with medical devices.
If a wireless network interferes with another wireless network, a clinician may lose a connection and have to get back on the network, or re-access data. But if a wireless signal interferes with a medical device, it can put a patient at risk.
"We had a demonstrated case where a patient talking on his cell phone caused his infusion pump to malfunction and go to the highest setting," says David Gravender, vice president and CIO at Kaweah Delta Health Care District, a Visalia, Calif.-based delivery system anchored by a 357-bed hospital.
In that case, the patient was receiving a saline solution and no harm occurred. But in another instance at the hospital, a woman on a cell phone was leaning against a telemetry closet and caused a brief loss of heart and brain electrical activity data on three patients.
And these events occurred even though the hospital regularly educates its staff on how to prevent wireless interference and restricts cell phone use to non-patient areas-with signs in prohibited areas reminding patients and visitors. "Patients see nurses using Voice over Internet Protocol phones and think they can use a cell phone," Gravender notes. "Their perception is the nurses are talking on a wireless phone, which looks just like a cell phone to them.
Wireless interference primarily happens in two ways. Radio frequency interference occurs when a "rogue" signal prevents a user from getting an adequate signal from a wireless network, television or radio station.
Electromagnetic interference occurs when those emissions from cell phones, pagers, two-way radios and other wireless devices change the flow and/or voltage of electrons in a medical device, which can cause the device to shut off or change its settings.
Interference can come in many unforeseen ways. For instance, notebook computers can interfere with a hospital's wireless network even if the user isn't trying to go online, says Sean Fischer, senior network consultant with the ACS Healthcare unit of Affiliated Computer Services Inc. of Dallas.
That's because an internal radio in the notebook will search for a network connection. "Hospitals without a public wireless network should have a policy to make sure patients turn off the internal radio," Fischer advises.
A wireless network in an adjoining physician practice can interfere with a hospital's network. Even a nearby apartment complex with lots of home network systems can interfere with a hospital's network.
Conflicts
In addition, different wireless networks in the same facility can conflict with each other. One cause might be that the networks overlap and modifying antenna directions and signal strengths can resolve the problem. Or, both networks are operating on the same frequency in the 2.4 GHz wireless band and the same channel within the frequency.
Cordless telephones also can pose similar problems for networks. "Our recommendation is to not run a 2.4 GHz phone with an 802.11b or g wireless network," says Carlo Gagliardi, also a senior network consultant at ACS Healthcare.
I.T. Spotlights
- About Us
- Advertising/Media Kit
- Reprints
- Editorial Calendar
- Contact Us
- Customer Service
- Privacy Statement
©2008 HealthDataManagement and SourceMedia, Inc. All rights reserved.
SourceMedia is an Investcorp company.
Use, duplication, or sale of this service, or data contained herein, is strictly prohibited.
