Pulling off a finger plaster is one of life’s little trials that can reveal a lot about a person. Do it fast or do it slow, it still hurts like heck and there’s no pretending that it didn't. For an adult, it’s an instant of pain, but for a newborn it can mean injury or even permanent scarring. In order to prevent this, a team of researchers are developing a new medical tape that can be pulled off safely without tearing delicate infant skin.
Removing medical tape from a newborn is a serious matter because they haven’t had time to grow the tough epidermis that protects the skin from harm. This means that tape needed to attach medical instruments, respirators and IV drips to newborns runs the risk of damaging the little one. This is particularly worrying, since premature infants are both the most in need of intensive care and the most vulnerable. When the elderly, who also have fragile skin, are included, over 1.5 million people each year face scarring and irritation from medical tape.
“When you take the tape off, you take the skin off,” said Don Lombardi, CEO of the Institute for Pediatric Innovation (IPI), which conducted a survey of neonatal intensive care unit needs. “It’s very painful, obviously, and it scars them. Some end up with months of aftercare for lesions on their skin due to the tape.”
Medical tape is composed of two parts. One is the adhesive that makes it stick to the skin and the other is the backing, which is usually a thin polymer like polyethylene terephthalate (PET). Together, they help keep wounds clean, bind dressings and keep medical apparatus in place. Unfortunately, when the tape is removed this teamwork turns into a nasty alliance. The adhesive keeps doing its job of sticking to the skin while the backing’s strength and resistance rips it away – sometimes with the skin itself.
Previous attempts to fix this problem involved a weaker adhesive, but that just created a tape that doesn't stick properly. The new tape uses a third layer of silicone in between the backing and the adhesive. This silicone doesn't stick to the adhesive and the backing peels away easily.
This may sound like having no tape at all, but the researchers used a laser to etch a grid pattern in the silicone. This allows some of the adhesive to come into contact with the backing and hold it in place. The denser the grid, the stronger the bond. When time comes to pull it away, the grid is easily broken and the backing peels off, leaving behind the adhesive. This can then be sprinkled with baby powder and left to wear away without noticeable stickiness.
“You end up with just a very fine coating of powder,” says Bryan Laulicht, a postdoc in MIT’s Institute for Medical Engineering and Science. “But when the residual powder has been washed off, you can go ahead and place another adhesive on top immediately and it sticks just as well as if you had stuck it directly onto the skin.”
One advantage of the new tape is that, aside from the silicone layer and the laser, it doesn’t require any new materials or manufacturing processes, so it should be relatively easy to put into production. The tape has done well on model surfaces and the team is now trying to get regulatory approval for trials on human adults.
The new tape takes a similar but different approach to a medical tape from 3M that is also designed for pain-free removal. Both use silicone, but the 3M tape uses it in the adhesive rather than as a layer between the adhesive and the backing.
The team behind the new tape included Jeffrey Karp, associate professor of medicine at Harvard Medical School and co-director of the Center for Regenerative Therapeutics at Brigham and Women’s Hospital, Bryan Laulicht, and MIT Institute Professor Robert Langer.
Their work was described in the Proceedings of the National Academy of Sciences.