The sensor patch can be embedded into the dressing that fixes a cannula in place.
A significant number of hospitalized patients require the insertion of a thin tube, called a cannula, into a vein, usually in their hand or arm, to facilitate easy and sometimes lengthy delivery of drugs. If the vein is small or fragile, such as is often the case in infants and the elderly, or the cannula is misplaced or moves, the drugs can leak into the surrounding tissue, causing swelling, pain, and sometimes, in severe cases, death of the tissues and impaired function of the limb. Clinicians and nurses do monitor the cannula site for leakage, but this can sometimes be challenging and very small leakages can be missed.
Researchers at the Agency for Science, Technology and Research (A*STAR) Institute of Microelectronics in collaboration with clinicians from KK Women’s and Children’s Hospital in Singapore have developed an adhesive sensor that can detect as little as two millilitres of leaked fluids. The sensor can be incorporated into the dressing normally used to fix a cannula in place.
It is made of very thin electrodes embedded between two elastic polymer substrates. The electrodes stretch when a leakage into the tissues stretches the skin. This in turn changes the resistance in the sensing electrode, which is detected by a ‘reader’ connected to the sensor. The reader is battery-run and reusable, while the sensor patch is disposable and does not require a battery.
The team has successfully tested its sensor in lab experiments. The researchers next plan to develop a wireless module that can wirelessly alert healthcare workers of a leakage through a mobile application, allowing for immediate intervention.
They will also work on making the sensor more cost-effective: they expect it to cost less than US$1 per sensor patch. Further work will include conducting more comprehensive clinical trials for the sensor patch system.
Further information
Dr Ming-Yuan Cheng | E-mail: [email protected]
Institute of Microelectronics
Agency for Science, Technology and Research, Singapore
Meet the Expert:
Ming-Yuan Cheng received the B.S. degree from the National Yunlin University of Science and Technology, Taiwan in 2000, the M.S. degree from National Cheng Kung University, Taiwan in 2002, and the Ph.D. degree from National Taiwan University, Taiwan, in 2009, all in mechanical engineering.
From 2009 to 2010, he was a postdoctoral fellow in National Taiwan University, Taiwan. In 2010, he joined the Institute of Microelectronics (IME), A*STAR, Singapore, where he is currently a scientist and bio-packaging group leader in the Interconnect & Packaging and More-than-Moore (IPP-MtM) department.
Ming-Yuan and his team are working on microassembly, bio-packaging and encapsulation for implantable medical devices in IME. These medical devices include smart sensor patch for early detection of extravasations, dry electroencephalogram (EEG) electrodes for long-term epilepsy monitoring-TBC, sensorised guidewire for endovasular guidewire intervention application and neural probe array system for neural recording to help paralysed patients to regain independent mobility.
Dr Ming-Yuan Cheng
