A smart sticker that could alert people with asthma of an impending attack, has been made using a children’s toy.
The device is made using Shrinky Dinks – plastic sheets that shrink to a fraction of their original size when heated. They are popular among children because they can be coloured and cut into shapes before shrinking.
The Shrinky Dinks are used to shrink ultrathin metal sheets into stretch-detecting sensors that wirelessly transmit breathing data to a smartphone. The hope is that this data could be analysed to detect subtle changes in breathing rate that may be early signs of a worsening condition, or track improvements following medical treatment.
It could be a useful tool for monitoring people with chronic lung conditions, such as asthma and cystic fibrosis, says Michelle Khine at the University of California, Irvine, who led the team. People will use the device by sticking it to their lower ribs.
The device monitors changes in electrical resistance as it stretches and retracts on the skin. When the wearer is still, the sensor’s measurements are as good as a medical-grade spirometer – a machine that measures lung volume from how much a person breathes out in a forced breath, says Michael Chu, one of the team.
Spirometry is still the most accurate approach, but the new method has the advantage of continuous monitoring over time. Currently, the sensor becomes less accurate when the wearer is very active, for example, if they are running.
Khine says the next step is to use the device to try to predict asthma attacks before they happen.
Original paper: Digital Medicine