In Review
IRON SAFETY: The research teams of Mitchell Anthamatten, an assistant professor of chemical engineering (left), and Christopher Lentz, the director of the Strong Regional Burn Center, teamed up to develop a prototype for a “safety shoe” designed to prevent kids from burning themselves on clothing irons. (Photo: Richard Baker)When doctors see a pattern in the cause of injuries they treat, what can they do? For a physician at the Medical Center, the answer was simple: Become an inventor.
Since 2003 more than 200 children have been admitted to the Strong Regional Burn Center with injuries from contact burns. About 10 percent of those were burns caused by a hot clothing iron.
“We’ve always tried to do proactive things,” says Christopher Lentz, associate professor of surgery and pediatrics and director of the burn center. “It’s an essential part of our mission.”
The search for a solution has brought together a team of Rochester surgeons and chemical engineers. Together they have developed a prototype for a silicone “safety shoe” that effectively shields the heat of an iron from the curious hands of youngsters when the appliance is not in use.
The prototype, unveiled this winter, is the result of nearly three years of collaboration between clinicians, engineers, students, firefighters, and community organizers to address a problem that Lentz faced as an expert on burns among young children.
The children Lentz was seeing—at the “exploratory age” of five years and younger—tended to come from lower income families where, Lentz hypothesized, the ironing is more likely to be done on a bed or the floor rather than on an ironing board.
“Surgery to graft new skin over the area is often necessary with these burns, which comes with a five-day stay in the hospital and a month of recovery time,” says Lentz. “Some children suffer a permanent loss in their sense of touch on the injured fingertips, and scar tissue on the back of hands may hinder movement. We grew tired of watching these kids come in and decided to try to do something about it.”
Initially, Lentz considered finding a way to provide ironing boards to families in need. But his colleague and wife, physician assistant Dixie Reid, had an idea. Why not develop a device that would shield children from the heat of the iron?
Such a tool, Lentz thought, could dramatically affect the incidence of injury—much the way smoke detectors have reduced the number of smoke inhalation victims.
But such invention isn’t a skill for which surgeons are usually called upon.
“It’s basically a physics question,” says Lentz. And so he went in search of a colleague who could help him.
He found one in Mitchell Anthamatten, an assistant professor of chemical engineering and an expert in materials science.
In 2005 they, together with Reid and clinical research resident Steven Kahn, received a grant from the International Association of Firefighters to support research into the problem. They formed a task force bringing together the burn center, the chemical engineering department, the Rochester Fire Department, a regional burn association, and a local coalition to protect children from injury.
Medical student Ryan Beers, who was in Rochester carrying out summer research at the University, established that it takes 90 minutes for an iron to cool to a safe temperature. A survey of patients and families in the burn center showed that most believed it takes only 20 minutes. Armed with the new information, the group developed a brochure on iron safety.
Meanwhile, Anthamatten, who teaches the chemical engineering course Heat and Mass Transfer, brought his students in on the problem. He asked them to design an effective, low-cost device that would prevent children from being burned by irons.
“The students really appreciated the assignment because it let them put heat transfer in the context of a real problem,” Anthamatten says.
“Students had many intricate ways to cool the iron fast. A few students identified a simple way: Instead of cooling the iron, shielding it.”
After considering several materials, Anthamatten and Lentz arrived at a silicone material that can withstand unusually high temperatures while also acting as thermal insulator. The idea is simple: Isolate the hot surface from its surroundings to prevent heat from coming in contact with small hands and other vulnerable surfaces.
The “safety shoe” they developed is molded from a polymer made by Dow Chemical, which retains its shape and performance even following 2,000 hours of 500 degree Fahrenheit heat. Users can leave a hot iron in the shoe when no longer in use. The surface on which the iron rests within the shoe has raised bumps to create insulating air gaps that further isolate the iron’s hot surface, and the shoe’s sides are high enough to protect children from the iron’s hot edges.
In a report published online in the December edition of the Journal of Burn Care & Research, the team showed that the shoe was easy to use, safely shielded the edges of the iron, and did not melt or deform. The temperature on the outside of the shoe did not exceed the burn safety threshold of 120 degrees Fahrenheit when a hot iron was unplugged and placed in it. And even when the iron was left on while it rested in the shoe, the safety shoe reached a temperature of only 212 degrees Fahrenheit, well below the temperature at which paper catches fire.
“A device, be it the iron-shoe we came up with or something similar, could easily be used to lessen the risk of iron exposure. Having a quick, convenient way to shield the iron surface” would make burns less likely, Anthamatten says.
“The elastic polymer shoe proved to be the best idea, and we believe it, or a similar device, could really make a difference if a company decides to invest in it,” he adds.
“We sought help from the chemical engineers for a clinical problem,” Lentz says. “I think this should happen more often. We need to start building bridges between these different disciplines.”
Such collaboration is among the priorities of the Medical Center’s new strategic plan. And Lentz is already at work on his own next collaborative project: Finding a way to avert pressure ulcers, commonly known as bedsores.
“They’re a lot easier to prevent than to fix,” he says, and he is talking with University engineers about their ideas for how to relieve pressure on patients’ skin.
“We’re trying to do something to prevent a problem rather than treat a problem over and over.”
