Homecare helper: 'Magic' wand pairs medical devices to Wi-FiHomecare helper: 'Magic' wand pairs medical devices to Wi-Fi

The number of patients using remote medical monitoring devices soared 51% in 2015, with nearly five million people using the technology across the globe, according to Berg Insight. This trend will continue, maintaining a 48.9% compound annual growth rate through 2020, notes the Sweden-based market research firm. As medical care moves out of the hospital and into the home, usability of these types of devices by non-professionals and patient confidentiality, in cases when those devices wirelessly transmit data to patient care facilities, are becoming paramount concerns. Researchers at Dartmouth College (Hanover, NH) believe they have an answer: An electronic wand—the prototype has been dubbed Wanda—that pairs medical devices to Wi-Fi simply and securely.

"Quite frequently in the computer security business, we invent things that are super-secure but hard to use, and people don't understand them," Wanda's creator, Tim Pierson, told Phys.org. "We set out to make something that my parents and in-laws could use."

Wanda seems to fit that profile. In an as-yet unpublished paper written by Pierson and his team, he describes a typical scenario involving a patient using a wireless blood pressure monitor at home designed to transmit the data to the patient's electronic health record (EHR), where it can be accessed by a medical professional. Given current technology, at least three problems arise, write the researchers.

"The first problem is that blood-pressure monitors, like many [Internet of things] sensors, do not normally come with long-range communication connections; they have short-range radios such as Wi-Fi, Bluetooth, or Zigbee. The blood-pressure monitor must somehow get connected with other devices in the home, such as a Wi-Fi access point in order to transmit its medical data to the physician's EHR system. Making those connections is difficult for many people, especially considering that different types of devices from different manufacturers often have different methods of making a connection and that the devices themselves often have very limited user interfaces."

Then, once a connection has been made between the blood-pressure monitor and a device capable of transmitting data long distances, note the researchers, the blood-pressure readings must get to the right patient record in the right physician's EHR system.

A third problem occurs when devices partner with other nearby devices so they can work together in a peer-to-peer fashion, such as a blood-glucose monitor working with an insulin pump. "In these peer-to-peer cases, the devices may
maintain a connection with a long-range communication device, but may also need a connection with neighboring devices using encryption based on a unique key for a specific pair of devices, rather than a common key shared by all devices. Establishing the encryption can be difficult if the devices have never met before and have never shared a secret key," writes Pierson.

Using Wanda, the patient simply points the wand at a Wi-Fi-enabled blood pressure cuff at home to automatically connect with the network and securely transmit the readings to the doctor's office or clinic. There's no need to type in a password to connect the wand—"a lot of people who have Wi-Fi in their homes . . . have no idea what their password is," notes Pierson. Moreover, Wanda does not require specialized hardware in the new device, preshared secrets between the wand and connected device or complex algorithms, add Pierson and his fellow researchers in the paper.

The prototype consists of a ruler with two antennas attached to it, writes Phys.org. "It can acquire a network name and password by being plugged into a Wi-Fi router, and is then detached and pointed at the medical device to connect it to the network. The password information is converted into binary code—ones and zeroes—with one antenna transmitting information packets containing the "ones" while the other sends the "zeroes."

"Because the medical device is close to the wand, it can tell which packet came from which antenna based on the signal strength and can reconstruct the information. But a hacker farther away couldn't tell the difference," explains Phys.org.

Of course, blood pressure monitors are but one potential application for this technology, as more and more medical monitoring devices take up residency outside of hospitals and clinics.

Pierson's project is part a $10-million, five-year grant from the National Science Foundation to Dartmouth, Johns Hopkins University, the University of Illinois Urbana-Champaign, the University of Michigan and Vanderbilt University.