Noninvasive Device Warns When Wounds Are Bleeding

WRITTEN BY: Tara Fernandes

Patients with kidney failure have to undergo hemodialysis—a process where a dialysis machine takes the place of kidneys to “clean” the blood. Before the procedure, minor surgery is usually performed to insert a catheter into the blood vessels, allowing the blood to flow through the machine. After dialysis, the catheter sites are then bandaged and patients are kept warm under blankets as they recover.

During this time, medical staff need to perform routine inspections (as often as every 15 minutes), to be on the lookout for potential bleeding from the catheter site.

This labor-intensive procedure could soon be replaced by a lightweight smart monitoring device applied on top of the patient’s bandage. The sensor provides real-time information about whether wounds are bleeding. Researchers tested this Blood WArning Technology with Continuous Haemoglobin (or BWATCH) sensor in a cohort of 250 patients undergoing dialysis. Excitingly, the technology managed to detect all 36 instances of bleeding, instantly triggering an alarm to alert nursing staff.

"Heavy bleeding following medical procedures is rare but when it occurs, it can be life-threatening. Monitoring at short intervals is highly manpower intensive but necessary. However, despite close monitoring, bleeding may still occur between these inspections. BWATCH offers continuous monitoring, allowing the care team to focus on other patient-centric tasks," said Chionh Chang Yin, a senior author of the study.

The BWATCH sensor detects hemoglobin in the blood (differentiating it from other bodily fluids such as sweat) and non-invasively sits on the outside of their wound dressings. In the future, the researchers plan to expand the application of this technology to watch out for bleeding in traumatic wounds and in incisions following other medical procedures.