Researchers at Stanford University have developed a biodegradable blood flow sensor that can be wrapped around an artery during vascular surgery, and then monitor blood flow thereafter. The battery- and wire-free device can let a clinician know if a vessel is blocked, helping them to address complications after surgery before they become a significant problem. As the sensor is biodegradable, it does not need to be surgically removed later, and simply breaks down and disappears.
Assessing whether vascular surgery has been a success can be difficult, and sometimes if an issue develops, it can be too late to easily treat it. In fact, in such circumstances a patient may need a second vascular surgery. If doctors could monitor blood flow through a recently repaired vessel they could see issues develop ahead of time, and potentially deal with them before they become a problem. This matter inspired a group of researchers at Stanford to develop an implantable blood flow monitor that surgeons could wrap around an artery during a vascular surgery, but which would not need to be removed later.
The pulsing vessel distorts the inner surface of the sensor, which changes its ability to store an electrical charge. This property can be measured wirelessly by a device outside the body, which can connect to the antennae of the sensor, providing a wireless blood flow measurement for clinicians. In the future, the researchers hope that the external measurement device could be incorporated into a wearable or smartphone.
To create the blood flow monitor, the research team adapted sensor technology they had previously developed to give patients with prostheses a sense of touch. “We were always interested in how we can utilize these kinds of sensors in medical applications, but it took a while to find the right fit,” said Zhenan Bao, a researcher involved in the study.
So far, the researchers have tested the device in rats, and even in this miniaturized form, the implant successfully provided blood flow data when attached to a rat artery. However, the sensor has numerous other potential applications. “Measurement of blood flow is critical in many medical specialties, so a wireless biodegradable sensor could impact multiple fields including vascular, transplant, reconstructive and cardiac surgery,” said Paige Fox, another researcher involved in the study.
Study in Nature Biomedical Engineering: Biodegradable and flexible arterial-pulse sensor for the wireless monitoring of blood flow
Via: Stanford University