April 28, 2007. A trainee doctor was bandaging a diabetic foot wound of a lady. Let’s call her Fiona. Fiona was a veteran of the diabetic clinic. Her file was 2 inches thick, and she knew about dressing a wound better than most of the trainee doctors. She was also very frustrated as the wound just would not heal! And while her diabetes was well controlled, she was there every month, with the same wound that would almost heal and go bad again.
At that time, the doctor often wondered what it would be like to have a dressing that could talk to him. If the dressing could tell him the condition of the wound without even removing it. If the dressing could deliver a dose of medicine without him having to disturb the delicate granulation tissue that forms the base of a healing wound.
10 years later, this hope is coming to life. A new ‘smart bandage’ is in making, and this will revolutionise the way wounds are treated today!
Till the start of this century, doctors were also philosophers. Some were physicists, some chemists. This multidisciplinary background helped them to overcome many diseases, leading to many discoveries. As medicine specialised, doctors became more focussed on treating, and thus lost the subtle touch with the development part of new therapies. Fast forward a few decades, Universities are promoting multidisciplinary teams again to tackle the problems of delivering healthcare.
A similar team from Tufts University, USA, has developed a prototype smart bandage. This bandage can sense the condition of the wound and deliver a dose of medicine when needed. This is a revolution in two aspects.
Firstly, knowing the condition of the wound without opening a bandage is a huge deal. Many times, the patient is sent home with a bandage. Due to improper care, the wound may not heal well, or even become infected. This is often discovered too late, during a routine visit to the doctor. So, if a patient gets an alert on his phone to see a doctor, an infection can be tackled earlier.
And secondly, the current dose delivery systems like patches deliver a constant dose. They are not customised to deliver a dose when needed. So, delivery of medicine when required or as doctors call it, SOS application, will improve wound healing.
How does a smart bandage work?
The smart bandage takes into account the pH and the temperature of the wound. A normally healing would have a pH between 5.5 and 6.5, whereas an infected wound may have pH well above 6.5. The temperature is raised in an infected wound, a marker of inflammation.
The team lead by Sameer Sonkusale, PhD professor of electrical and computer engineering at Tufts University has developed a smart system of reusable electronic components integrated into the bandage. The patch senses the pH, temperature, and tissue oxygenation, and sends the data to a device with Bluetooth. This will help in the collection of data and delivery of medicine.
The bandage has two parts. A reusable electronic module that connects to a Bluetooth device and a disposable bilayer patch with sensors and therapeutics. The two are attached by a detachable flex cable that allows a change of patch. The patch has sensors that sense the pH and temperature and sends the signal to the electronic module. The patch also has a hydrogel layer that holds the medicine in place. So, a signal from the electronic module can release the drug to the wound by using heat.
3D printing and reusable parts make the bandage cheaper to use, and the thinness of the patch makes it practical for complex wounds. This system has been tested in vitro-human trials are still not performed. However, this is a hope for those like Fiona who need some smart tech to ease their pain.
We are indeed fortunate to live in such exciting times!