New wearable device to predict, prevent asthma attacks

Researchers, including one of Indian-origin, have developed an integrated, wearable system that monitors a user's environment, heart rate and other physical attributes to help predict and prevent asthma attacks.
The system called Health and Environmental Tracker (HET) is composed of a suite of new sensor devices.
Asthma patients currently rely on inhalers to deal with their symptoms, which can include often-debilitating asthma attacks, researchers said.
"Our goal was to design a wearable system that could track the wellness of the subjects and in particular provide the infrastructure to predict asthma attacks, so that the users could take steps to prevent them by changing their activities or environment," said Alper Bozkurt from North Carolina State University (NC State) in the US.

"Preventing an attack could be as simple as going indoors or taking a break from an exercise routine," said James Dieffenderfer from NC State.
The HET system incorporates a host of novel sensing devices, which are incorporated into a wristband and a patch that adheres to the chest.

The patch includes sensors that track a patient's movement, heart rate, respiratory rate, the amount of oxygen in the blood, skin impedance and wheezing in the lungs, researchers said.
The wristband focuses largely on environmental factors, monitoring volatile organic compounds and ozone in the air, as well as ambient humidity and temperature, they said.

The wristband also includes additional sensors to monitor motion, heart rate and the amount of oxygen in the blood.
The system also has one nonwearable component - a spirometre, which patients breathe into several times a day to measure lung function, researchers said.
"Right now, people with asthma are asked to use a peak flow meter to measure lung function on a day-to-day basis," said Dieffenderfer.
"That information is used to inform the dosage of prescription drugs used in their inhalers," he said.
"For HET, we developed a customised self-powered spirometer, which collects more accurate information on lung function and feeds that data into the system," he added.

Data from all of these sensors is transmitted wirelessly to a computer, where custom software collects and records the data, researchers said.
"The uniqueness of this work is not simply the integration of various sensors in wearable form factors," said Veena Misra from NC State.
"The impact here is that we have been able to demonstrate power consumption levels that are in the sub-milliwatt levels by using nano-enabled novel sensor technologies. Comparable, existing devices have power consumption levels in the hundreds of milliwatts," said Misra.
The findings were published in the IEEE Journal of Biomedical and Health Informatics.