Imagine caring for a small, frail patient like a premature child. In addition to having to watch out for IVs and feeding tubes, you'd have to navigate around pulse oximeters, blood pressure cuffs, EKG leads and additional monitoring equipment. Tasks as simple as changing a diaper or dressing the child become intricate processes requiring great care to avoid dislodging a sensor. Now, imagine what it would be like to care for that patient more directly--without any leads in your way and simply being able to attend to his or her needs. The new wireless medical device applications under development are making that hope a reality.
|The Nonin 3230 pulse oximeter could be the first wireless pulse oximeter to use Bluetooth Low Energy technology. The device is awaiting 510(k) clearance in the United States.|
The medical device industry is starting to witness a profound shift away from the cumbersome wire-based patient monitoring technology that has existed for decades. While wearable devices like the Holter monitor have helped to revolutionize patient monitoring, the spaghetti of leads and cables that accompanies them can be cumbersome for patients and caregivers alike. Now, wireless technology is enabling the development of devices that are more comfortable for patients that also collect patient data with unprecedented frequency and accuracy. Also contributing to this trend is FCC's allotment of spectrum for MBANs in 2012 was a significant milestone for the field of wireless patient monitoring.
Disposable MBAN Sensors
One way that manufacturers are trying to manage the cost of adding wireless capability to patient monitoring is to create low-cost, disposable devices. One example of this is the use of wireless temperature sensing to report back to a central monitoring station, letting nurses track patient temperatures remotely. These disposable devices also allow each patient to get her own monitor, reducing the risk of cross contamination. Constantly turning over equipment also allows every patient to use the newest possible technology.
Disposable devices typically don't use the same elaborate technology as wearable devices. Most either use near-field communications, which have the benefit of being related to readily available RFID technologies and even being built into smartphones, or a proprietary standard. This helps to keep them simple and inexpensive. However, it also limits their applications due to their systems' limited capabilities and data transfer rates.
The technology behind these disposable devices is not just on the drawing board--it's in use now and it is projected to grow substantially. ABI research projects that five million of these sensors will ship by 2018, putting a range of wireless medical device applications into real-world patient care settings.
Bluetooth Low Energy
The Bluetooth Low Energy standard is similar to the Bluetooth system widely used by biometric monitors for exercise equipment. Unlike those systems, though, it has lower power drain requirements. Devices like Nonin Medical's pulse oximeters take advantage of Bluetooth's ease of use and secure transmissions. The low energy standard will enable additional Bluetooth Low Energy wireless medical device applications by not only consuming less power but also providing different ways for devices to connect to their monitoring stations, hopefully alleviating some of the spectrum congestion concerns that impact other wireless systems. Bluetooth Low Energy also works with popular computing platforms like Microsoft Windows 8 and Apple products, allowing doctors and nurses to use their computers, smartphones or tablets to directly connect to the monitors.
Samsung's 5G Standard
Wireless medical device applications in the future will be able to transfer orders of magnitude more data than decies using today's wireless systems. The Samsung 5G standard, currently slated for release in 2020, allows for data transfer rates that are exponentially faster than current 4G systems. Right now, 5G radios are achieving speeds of over 1 Gbps over a two kilometer distance in test settings. This data transfer rate would not only enable high-speed in-hospital monitoring but can also allow give clinicians unprecedented flexibility and power in monitoring patients remotely. For example, high-resolution images from MRIs or other body scans can be delivered wirelessly in seconds over a 5G network.
Powering Wireless Medical Device Applications
While wireless technology opens up an array of possibilities for medical device engineers, the technology also poses problems. For instance, powering wireless devices can be problematic; it doesn't make a great deal of sense to swap monitoring leads for power cables. Researchers are also working on new solutions for on-patient power. While a shoe-powered 400mA generator might be a potential solution for an ambulatory patient, a flexible battery could be sewn into a bed-ridden patient's hospital gown and coupled with wireless power technology to allow a lead-less connection to the MBAN. Implantable sensors currently under development can pick up energy from body fluids or body heat to power themselves.