The wireless networks that connect electronic medical record systems to medical devices are rapidly evolving. Elly Earls talks to Philips' Paul Coss and Delroy Smith and Welch Allyn's Garrison Gomez about two of the primary types of infrastructure available to transmit life-critical patient data.
Hospitals have been using wireless networks – in their earliest form – since the late 1960s. But the industry has been much slower in adopting the technology on a large scale than its counterparts in the consumer electronics sector, for a variety of reasons.
While a dropped mobile phone call is mildly frustrating, a lost patient monitoring signal can mean the difference between life and death, and the infrastructure supporting the transfer of such data must be suitably robust, something that, until recently, has not been the case.
Electronic medical record (EMR) systems have only been widely adopted in the last four to five years, another factor that has hindered the implementation of comprehensive wireless infrastructure in healthcare facilities. Although EMRs are by no means a feature in every hospital in 2011, their return-on-investment potential means there is now significantly more incentive for hospitals to install a facility-wide network.
On top of this, stringent regulations governing the transfer of medical data mean networks must be built to strict criteria, taking into account the need for real-time information, low latency, high availability and excellent quality of service.
However, as the adoption of EMRs quickens and healthcare facilities move from paper-based to computer-based charting, momentum is building towards the widespread installation of medical grade wireless networks. Already established in this arena are Philips and Welch Allyn, the former offering a telemetry system with smart-hopping technology and the latter a standard 802.11 a / b / g network.
Philips’ 1.4GHz and 2.4GHz IntelliVue Telemetry Systems with smart-hopping technology offer surveillance of ambulatory cardiac patients, an area in which it is essential that patient information is available when and where it’s needed, whether the source is a wireless monitor, a networked bedside monitor or a laboratory information system.
The IntelliVue Telemetry System provides clear two-way communications between transceivers and the IntelliVue Information Center. Smart-hopping technology dodges interference and seeks out the strongest signal available to achieve seamless connections wherever patients roam on the network. It also manages bandwidth usage efficiently, meaning the system is highly scalable. "It’s a stable, dependable solution," says Delroy Smith, project leader at Philips. "It’s a protected system and allows the user to forget about the system because it just works."
For Paul Coss, Philips’ director of marketing for critical care, the robustness of the smart-hopping network is its key feature.
Within a hospital, different devices have various levels of priority; for example, an infusion pump that needs a new bag has an hour to communicate that information, whereas the data indicating that a patient has had a life-threatening event needs to get through immediately.
"Traditionally, hospitals have deployed everything on Wi-Fi, but there are challenges to that," says Coss. "The smart-hopping network deals with the latency and the real-time urgency, and provides a solution that is robust enough for hospitals to rely on the fact that, if something’s going to happen, they will get that information."
The IntelliVue Clinical Network is designed specifically to manage flows of time-critical, round-the-clock patient monitoring data, and at the same time can maintain a controlled connection with the hospital LAN, so that patient information, including lab results, can be delivered to the bedside monitor or central station without risk of disrupting the flow of physiological data or alarms.
While the feedback from Philips’ customers has been positive, there are inevitable challenges when designing products in such a fast-moving industry. "It takes two to three years to get a product to market," says Coss. "So the requirement of the customer is always a bit ahead of where the technology is." On top of this, there is no standard frequency, excluding Wi-Fi, that exists worldwide, so another challenge for manufacturers is the requirement to produce different solutions for different markets.
Many hospitals also remain slightly suspicious of the latest telemetry solutions, convinced that smart-hopping technology will disturb the Wi-Fi infrastructure already in place.
"With St Olav’s Hospital in Norway, we went through a demonstration to show them that our solution could co-exist with their existing networks and that was a very positive story for us," explains Smith. "The wireless space is starting to get very crowded, but we have been deploying very sophisticated adaptive technology to cope with this environment."
Security is perhaps the most common issue raised by users of life-critical wireless infrastructure. On top of using advanced encryption algorithms across the Philips networks, the company, which has been operating in the wireless environment for over 30 years, uses ‘make before break’ technology, rather than the traditional ‘break before make’. This means any device is connected to two spots at the same time, rather than being handed off like a trapeze artist from one to the next.
"The typical Wi-Fi infrastructure doesn’t have a very good roaming algorithm," Smith explains. "So, you often get data loss moving data from access point to access point. We’ve spent a lot of time working on getting roaming to work as fast as we can to avoid data losses."
One issue related to this that has been widely reported in the US is ‘alarm fatigue’. A Boston Globe investigation has claimed that more than 200 deaths across the US over the past five years have been associated with problems with patient monitor alarms. ‘Alarm fatigue’, the response – or lack of it – of nurses to more than a dozen types of alarms that can sound hundreds of times a day, many of which are false alarms, is said to be culpable.
"If your system is having lots of dropouts and lost signals, these become nuisance alarms or system alerts," Coss says. "And if the system is being inundated with these, it won’t take long before the nurses simply stop paying attention to the monitors. This is part of why we built our particular network; it’s reliable and you don’t get data loss."
In contrast to Philips and the majority of its competitors, Welch Allyn uses a standard 802.11 a / b / g network to connect its medical devices.
"We really use the same network that your laptop or any other consumer-grade devices would be on," explains Garrison Gomez, director of integrated solutions at Welch Allyn. "We’re seeing a convergence of this happening more and more; hospitals are asking to have all these devices on the same network instead of on proprietary networks. Our ability to do wireless on a shared network is one of our competitive advantages."
The solution is called FlexNet technology and it allows hospitals to operate real-time patient monitoring on their shared 802.11 a / b / g networks. Advantages include no proprietary infrastructure components and certificate-based authentication in each device that supports HIPAA requirements. Welch Allyn’s network was created in partnership with Aruba and Cisco.
"Originally, we had a vision that we’d be able to carry out continuous monitoring outside of the traditional ICU area," Gomez explains. "We wanted to be able to do it on the medical and surgical floor and in order to do that we needed to have a more open approach to networking.
"At the time, medical grade 802.11 networks were not available, so we partnered with Aruba because the company was flexible, being a smaller player, like ourselves. It wanted to partner with us to make modifications to its software and accommodate some of the needs we had. We’ve actually had to make modifications with both Aruba and Cisco to get them to update their code and support continuous monitoring. They’ve done it in parallel for video for other consumer-based electronics as it’s another area where there can be no data loss."
The company also participates in Cisco’s Assurewave programme, which tests the interoperability of 802.11 devices, as well as the HIMSS interoperability programme, proving that the technology has connectivity to EMRs, wirelessly and wired. Security is top priority for Welch Allyn’s networks; the devices are equipped with standard roaming security, which is typically WPA2-PSK, and the company also has the ability to authenticate clinician and patient ID through barcode scanning.
Moreover, in the unlikely event that the network does go down, all is not lost. "We’re always a medical device first and foremost," says Gomez. "If the network goes down, we’d still be monitoring at a local level on the device. You’d give an alarm to the central station saying you’d lost connectivity and a team would be dispatched to find out why. But we would never stop being able to monitor the device physically at its location."
Like Philips, Welch Allyn has received good feedback on its products, particularly the Connex Vital Signs Monitor, with many customers reporting that they are buying the device as a future-proofing option, hoping to connect it over the next couple of years as they adopt EMRs.
Challenges have presented themselves along the way too. "Probably the biggest challenge we have is that, with traditional medical devices, we would typically work with biomedical engineers in the hospital, but with networking, we work with IT," says Gomez. "In many hospitals, the IT staff and the biomedical staff aren’t necessarily aligned, so we faced challenges getting both parties to agree."
A question of liability
"There’s one question that a lot of people – including us – ask on a regular basis: ‘Where does liability lie?’," Gomez acknowledges. "You have the EMR, you have the network, you have our devices, you have the hospital and it’s probably a combination of all of them that brings things together."
It’s a question that the Food and Drug Administration (FDA) and the International Organisation for Standardisation (ISO) have also been asking as more hospitals and clinics plug patient monitoring equipment and other medical devices into wireless networks. In 2008, the FDA released its Medical Device Data System proposal, which is aimed at reclassifying health IT.
The proposed regulation would define medical devices as anything that provides electronic transfer, exchange, storage, retrieval, display or conversion of medical device data without altering the function or parameters of any connected device.
Although this regulation is not yet in operation, the fast-evolving wireless environment means the FDA is coming closer to implementing it.
The FDA also encouraged the ISO and the International Electrotechnical Commission (IEC) to draft a standard addressing management risks associated with medical grade IT networks. In November 2010, the IEC 80001-1 Risk Management Standard was finalised. For Smith, this level of thinking will allow hospitals to feel more comfortable as it defines the roles and responsibility of hospitals, vendors and network providers. It defines three key areas of risk management: the risk levels to patient health; the ability of a healthcare organisation to perform its duties; and the network’s ability to protect sensitive patient information.
The regulation is not mandatory, however, and the FDA is taking a carrot-and-stick approach to pushing compliance. Medicare and Medicaid offer incentives if the guidelines are followed, but if hospitals do not comply, there are two choices: the federal government inspects the facility or the hospital decides not to accept money from Medicare or Medicaid.
Importance of innovation
The potential new regulations have caused debate across the industry. "The other piece is that we don’t want the regulation to stifle innovation," says Smith. "That’s a balancing act." He notes that the FDA and the Federal Communications Commission are beginning to realise this.
In July 2010, the two bodies met to gain a better understanding of the convergence of communications technologies and medical devices, the future of wireless health technologies and the challenges they face.
"They were keen to understand what was going on so they invited the industry to bring in their devices and it was amazing to see the level of innovation going on, from small companies to large," says Smith.
"The big takeaway for the regulators was that there is tremendous innovation going on and they need to figure out how to manage it." Regulation and standardisation were key to the success of standard Wi-Fi infrastructure and for Smith, this also rings true for healthcare networks.
"It will give the vendors a secure space in which to work," he says. "If you look at the standard Wi-Fi infrastructure, it’s based on standards, which have been very beneficial in delivering innovations, and we expect the same to be true in the healthcare arena."