Digital cable television is a consumer's dream, offering on-screen TV guides and a clean, clear picture. But its ability to interfere with wireless patient-monitoring devices has prompted the Federal Communications Commission to take action to protect clinical data transmissions.
In February 1998, patient vital-signs monitors at Baylor University Medical Center in Dallas were disabled when a local TV station started testing its new digital signal. Although no patients were harmed, the interference sent a message to the medical community that too much data sharing the same airspace may pose a threat to patient safety.
"Our direct link to the patient was essentially wiped out," recalls Steve Juett, director of biomedical engineering at Baylor. The temporary outage, he says, affected Baylor's "ability to foresee the onset of a life-threatening event."
At the urging of the American Hospital Association, the FCC last month set aside airspace to protect wireless telemetry devices--such as heart monitors that transmit patient data to nearby nurses' stations--from potentially disruptive radio and TV broadcasts.
The FCC's rule will become effective about 90 days from the announcement.
The FCC's move was important because hospitals increasingly use wireless devices to monitor patient vital signs and keep tabs on medical equipment such as ventilators and intravenous pumps, says Mary Beth Savary-Taylor, the AHA's director of executive-branch relations.
Shortly after the Baylor event, the AHA set up a task force in conjunction with the FCC and the Food and Drug Administration to investigate establishing dedicated airspace.
"(The Baylor incident) was a real wake-up call not only to our hospitals but to Washington," Savary-Taylor says. "The most important thing is safety to our patients, and we needed the space set aside."
Without action, that risk would grow as the use of wireless devices and digital TV technology skyrockets nationwide.
Also participating on the task force were telemetry equipment vendors, including Tustin, Calif.-based VitalCom and Milwaukee-based GE Marquette Medical Systems, as well as hospitals such as Washington Hospital Center in the District of Columbia and Texas Children's Hospital, Houston.
The only data that will not be capable of using the dedicated airspace is voice and video, which would have eaten up too much of the available bandwidth, says Stephen Hannah, vice president of research and development at VitalCom. One example of such a use is monitoring patients remotely via video.
To use the dedicated airspace, hospitals will need to upgrade their telemetry equipment to new models that can take advantage of the FCC's action, Hannah says. According to the AHA, telemetry equipment in many medical centers is between 5 and 7 years old and ready to be replaced anyway.
How expensive it will be to replace those systems will vary widely from facility to facility depending on the number of telemetry devices in use.
Hospitals will not be required by the FCC to update their equipment because of the high costs. "It can take a number of months, maybe years, for a hospital to accrue the resources necessary to make these kinds of purchases," Juett says.
The Joint Commission on the Accreditation of Healthcare Organizations does not plan to update its standards to include use of the dedicated airspace. According to the JCAHO, existing standards for medical equipment management apply to safely using telemetry devices.
But not taking advantage of the dedicated airspace could put patient care at risk, says the AHA's Savary-Taylor. "We believe that for the sake of patients, (AHA member hospitals) will move over to the dedicated spectrum," she says.
Though hospitals won't be forced to act, the vendors who provide telemetry systems will be permitted to develop products that use the old airspace for only two more years. After that, anything they introduce to the market will be required to transmit on the dedicated airspace.
Medical centers in rural areas are not as susceptible to signal mix-ups as those in densely populated urban areas where airspace is more crowded. Even so, hospitals everywhere should assess their risk relative to competing signals and seriously consider using the new airspace once it is available, Juett says.
The FCC has made available resources on its World Wide Web site at www.fcc.gov/healthnet/dtv.html to help hospitals determine their level of risk and decide when and how to switch to the dedicated airspace.
