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These smart bandages talk to your doctor while speeding up healing
There has been little innovation in our medieval practise of wound care, but that is about to change, thanks to rapid advances in technology.
Elizabeth Cohen
A new generation of smart bandages that could allow doctors to remotely monitor wounds, decrease scarring and speed up healing with a zap of light or electricity is on its way.
These hi-tech bandages could eventually replace today’s usually simple constructions of gauze and plastic or latex, which can’t detect anything about the wound underneath and don’t do much more than apply pressure or hold a cream or ointment in place.
“We kind of are practising medieval medicine in wound care. It’s a lot of poultices and salves,” says Dr Geoffrey Gurtner, chairman of the surgery department at the University of Arizona College of Medicine, who is among those working to develop a smart bandage. “There hasn’t been a lot of innovation.”
Smart bandages are part of the burgeoning wearable-tech industry, aided by more advanced microsystems and flexible electronics, and fuelled in part by $80m in funding announced in 2019 by the research arm of the US Defence Department, to develop bioelectronics to help wound healing.
Now smart-bandage prototypes fill display halls at medical conferences. Many contain small electronics that can detect how a wound is healing and wirelessly transmit the information to a doctor.
Some enable the doctor to remotely dispense treatments. Such technical sophistication likely wouldn’t be necessary for a simple cut or scrape, but could be lifesaving for severe wounds treated in the hospital or chronic wounds cared for at home.
“You could have healthcare centres that monitor these devices and contact the patients when there’s a potential problem, and advise them on next steps,” says Dr William Tettelbach, a wound care specialist and president of the American Professional Wound Care Association. “I think it really is the future.”
Many of these inventions are in the early stages – some in animal or human testing, and others still in the lab – and far from coming to market.
“It’s a very hot area right now,” says Guillermo Ameer, a biomedical engineer and professor at Northwestern University in Illinois. “When we first started in this area five years ago, there were very few people, very few labs, looking at smart systems or smart bandages,” he says. “Now we have many researchers and colleagues, not only in the United States but in China and Europe, that are pursuing this.”
Many of the smart bandages use a piece of electronic circuitry that goes into a pocket in the bandage itself. When the bandage needs to be changed, the circuitry would come out of the pocket and be put into a new bandage. The circuitry is often flexible, such as that developed by a team of researchers led by Stanford University and described in a 2022 study.
Researchers at the University of Pennsylvania and Rutgers University are testing a bandage in mice and rats that can detect infection and then deliver electrotherapy – a zap of electricity – to help speed healing.
Some studies have shown that electrical stimulation can increase the migration of immune cells to kill germs and remove dead cells at the wound site, and randomised clinical trials have indicated that electrical stimulation can improve wound healing.
They envision the bandage sending reports via a cellphone app, says Yuanwen Jiang, an engineer and assistant professor at the University of Pennsylvania who is working on the project with Simiao Niu, an engineer and assistant professor at Rutgers University.
“The bandage will be able to transmit the signals of the wound in real time to the physician, so they will be alerted if there’s anything that’s dramatically off-track happening,” says Jiang, who was previously a postdoctoral fellow at Stanford and co-author of the 2022 study.
The bandage could also have the ability to deliver antibiotics, which could be stored in a small capsule or hydrogel. If infection strikes, a doctor could remotely order a valve to be opened and the ointment delivered to the wound. The theory is that if the antibiotic is delivered early and the wound heals easily, it would help avoid an overproduction of collagen, which can produce scarring. The team hopes to start testing in humans next year.
At Northwestern, Ameer is a principal investigator with teams that are working on two smart bandages, both of which have been tested in mice and are now being tested on pigs.
One dispenses a drug – in this case, a compound called panthenol citrate, which Ameer says has antioxidant and antibacterial properties and can encourage blood vessel growth.
The other smart bandage has two electrodes – a flower-shaped one on top of the wound and a ring-shaped one around it – that send out electrical currents to measure how moist it is. Moisture indicates the wound is still trying to heal, and a drier environment indicates healing is further along.
The bandage wirelessly transmits the moisture levels to the doctor, who can remotely program the electrodes to deliver electrotherapy, promoting the growth of new skin cells and blood vessels.
A tiny coil in the bandage, similar to those used to wirelessly charge cellphones, powers the system, and the entire electrical apparatuses is covered with a protective transparent tape. With electrodes made from a metal called molybdenum, which is thin enough to biodegrade, the entire bandage dissolves when its job is done. The researchers hope to start human testing with both bandages next year.
In other technologies, a team at the University of Southampton in England is developing a bandage that uses tiny LED lights to emit ultraviolet-C light, sterilising the wound as it heals. The bandage isn’t yet in animal trials.
Smart bandages might even go beyond wounds. The Southampton team, led by engineering professor Steve Beeby, is also working on a bandage to monitor atopic dermatitis – a common type of eczema that causes cracked, dry skin – using a sensor that detects moisture levels in the skin. It sends that information to doctors, who can use it to help determine whether a treatment is working.
Smart bandages could cost more to produce than traditional devices, and it is too early to say how they would be covered by insurance. But researchers say early detection and care for infections could ultimately save lives and medical costs.
Diabetics make up a large portion of those suffering from wound complications, with an estimated 160,000 hospitalisations for amputations among diabetic adults in 2020, according to the US Centres for Disease Control and Prevention.
Medicare expenditures for all chronic wounds in 2019 amounted to an estimated $33bn, according to a study published in the Journal of Medical Economics.
“I’ve seen patients that have had wounds for 10 or 20 years, and they’ve probably racked up millions of dollars, one hospital, one (doctor) visit at a time,” says the University of Arizona College of Medicine’s Gurtner.
A bioengineer as well as a surgeon, he is developing a smart bandage born of his experience at weekly wound clinics.
“I see patients on Tuesday, and they look good, everything looks good – they’re healing. And then you see them the following Tuesday, and they have rip-roaring cellulitis, and you have to send them to the emergency room to get an amputation,” he says. “At some point between those two moments in time, something changed.”
Gurtner is developing a bandage along with engineers at Stanford University. It uses electrical stimulation and biosensors to help increase blood flow to the injured tissue, close wounds more quickly and reduce infection. A thin electrical layer contains sensors, an electrical stimulator and wireless circuitry to power the electronics and provide Bluetooth transmission of data. Together, they measure the wound’s healing process, increasing electrical stimulation if the wound becomes infected or is healing too slowly.
In March, Gurtner’s team started testing the device on humans. The team expects the tests to conclude in 18 months, and then it will apply for approval from the US Food and Drug Administration.
One ultimate goal would be for the smart bandage to fix the problem without a doctor being involved at all. Gurtner – who has $250m in funding from the Armed Forces Institute of Regenerative Medicine, a collaboration of the Defence Department, academia and private industry – envisions his smart bandage being used to detect and treat infection in soldiers wounded on the battlefield.
THE WALL STREET JOURNAL
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Is there nothing those engineers won’t try to improve? I guess little harm can come from bandages that work better – save for the cost!
The market will decide I am sure!
David.