Draft Guidance Addresses RF Wireless Devices

NEWS TRENDS

FDA has acknowledged the increased prevalence of radio-frequency (RF) wireless equipment by issuing a draft guidance for medical devices that use the technology. Although much of the information might not be new to experienced individuals, the document identifies types of data and procedures related to RF wireless safety and effectiveness that FDA considers important.

“I believe the guidance will help make the submission and review process smoother,” William Saltzstein says. He is president of Code Blue Communications Inc. (Woodinville, WA). The fact that the guidance states the concerns and expectations for design, testing, and submissions could make the process easier, he explains.

The document focuses on wireless coexistence, performance, data integrity, security, and electromagnetic compatibility (EMC) related to RF wireless technology in devices. FDA is recommending that the following factors be considered:

Wireless manufacturers should also keep in mind that their devices could be coexisting with nonwireless or other RF wireless devices, not necessarily of a medical nature. William Kimmel, partner at Kimmel Gerke Associates Ltd. (St. Paul, MN), says one of the larger issues concerning wireless devices is frequency coordination. In other words, manufacturers must make sure that uncontrolled wireless devices do not operate in the same frequencies as sensitive and critical wireless hospital equipment.

“[In the past], the simple solution was that wireless wasn't allowed,” says David Case, regulatory technical leader at the Cisco Systems Corp. Compliance Standards and Operation Group (Richfield, OH). “That has changed. [FDA] has decided to devise a guidance on how wireless should be done to make it easier for industry to get a uniform process.” That way, he says, the agency knows that everyone is following roughly the same guidelines for installation.

When critical information is passed using RF technology, it's important that the wireless connection is strong. “Connections lost without warning, failure to establish connections, or even slight degradation of service can have serious consequences,” the guidance states.

“If the wireless network has a problem, if something causes interference, or if the system is getting the wrong data, you're now into an area where you could be endangering someone's life,” says Case. “You need to think about these issues when designing [equipment].”

Security also remains a concern because RF wireless technology makes it easier for eavesdropping to occur. To ensure the quality, integrity, and security of connections, FDA is recommending that EMC be a part of the design, testing, and performance process. A company's risk management scope should include intended use, anticipated misuse, sources of environmental electromagnetic disturbance, and the potential to affect other devices. During risk analysis, FDA suggests that manufacturers identify and continue to update possible adverse outcomes and their causes and severity of harm, as well as the control measures taken to reduce risks.

Although the draft guidance covers a number of RF wireless issues, there are still some factors that must be discussed in the future.

“More steps need to be taken,” says Kimmel, referring to the need for a quantitative set of requirements. “[FDA would] have to identify all of the allocated frequency bands and work with FCC to pin down what frequencies medical devices can use.” This would ensure that competing equipment wouldn't collide with each other or with items people bring into the hospital. “The wireless problems are technically feasible, but current users of radio bandwidth aren't going to give up anything without a fight.”

Saltzstein says the draft guidance left out the human factors element for manufacturers that are transitioning from wired to wireless devices. “We're all comfortable with the experience of troubleshooting a wired connection. Check both ends, make sure the connections are good and the wire appears undamaged, and change the wire if that doesn't work. Wireless is a different experience for these users, and they need appropriately designed systems and tools to be comfortable and efficient with the new technologies.”

“Draft Guidance for Industry and FDA Staff—Radio-Frequency Wireless Technology in Medical Devices” is available at www.fda.gov/cdrh/osel/guidance/1618.html. Comments are due by April 2.

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