Group creates safer surgical sponge
By Grace Afsari Mamagani, The Dartmouth Staff
Published on Friday, November 5, 2010
Following its creation of a bioresorbable sponge that could eliminate tens of thousands of dollars in revisionary surgery costs, a team of Thayer School of Engineering graduates — Nathan Niparko ’09 Th’10, Devon Anderson Th’10 and Jonathan Guerrette Th’10 — received second place in the undergraduate category of the Collegiate Inventors Competition, judges announced last week.
The team’s research attempted to address the issue of retained surgical sponges. In approximately one of every 5,500 procedures, a surgical sponge remains in the patient after surgery due to human error, Niparko said.
“This is a dangerous and expensive problem in operating rooms worldwide,” Niparko said. “The body forms a granuloma [a mass of immune cells used by the body to isolate substances it cannot eliminate] around the foreign object. If that gets infected, you can’t get any immune reaction there because it has been walled off.”
Instances of retained surgical sponges cause $1.38 billion in unnecessary expenses every year, according to Niparko. Of this sum, $66,000 is used to pay for each revisionary surgery necessary to remove the sponges, he said. Each incident also results in approximately $100,000 in legal expenses, including the costs associated with filing lawsuits for medical malpractice.
Niparko, Anderson and Guerrette chose to address the problem as part of the final design project concluding their two-term engineering design sequence at Thayer, according to engineering professor Doug Van Citters, who served as one of the team’s faculty advisers.
“Our thinking was that there were a couple ways to approach the problem,” Niparko said. “We could alter the way the sponges are counted in the operating room, but there have been numerous attempts at that in the past. We could find a better way to visualize them, but that’s been done as well.”
Over the course of the six-month project, the team developed a bioresorbable sponge made of chemically modified carbohydrates that will degrade in the body if left within patients, according to Anderson.
“It’s a combination of oxidized polymers [fabricated using] electrospinning,” Van Citters said. “They actually draw this out of a syringe needle and deposit it using electrostatic forces, creating a fine mesh … that is hydrophobic and has an extraordinary surface area. The end is something with great running capability, [that] can soak up many times its weight in bodily fluids and through hydrolysis can be broken down into constituents.”
Based on the design’s potential, Van Citters nominated the team for participation in the Collegiate Inventors Competition, an annual competition among student inventors that receives applications from more than 200 schools nationwide, he said.
“We were one of five finalists in the undergraduate category, so we flew down to [Washington], D.C., and met with a panel of judges,” Niparko said. “We gave a presentation that was similar to what the course at Thayer had prepared us for — the 190/290 course sequence [in engineering] had no homework or tests for grade. It was purely presentation-based.”
The team received the second-place prize in the undergraduate category and plans to continue to develop the bioresorbable sponge technology, Niparko said. The members have applied for a provisional patent and will apply for a full patent in March 2011.
“We’re also thinking about starting a business around it,” Anderson said. “Eventually, we’ll be ready to either develop it, take it through [the U.S. Food and Drug Administration] approval or sell it.”
The process of approval — which could take a number of years — will require proving that the products created when the sponges break down will not be harmful to the host, according to Van Citters. After a number of test trials performed on animals and humans, bioresorbable sponges may become the standard in operating rooms, particularly in surgeries involving small sponges that are difficult to monitor, he said.
“The magnitude of cost-savings simply by avoiding retained surgical sponges is enormous,” Van Citters said. “The benefits of implementing the new technology will far outweigh the costs after even one [retained surgical sponge] case is avoided.”
Anderson currently works at a Veterans Affairs hospital working exclusively to expand this technology, according to Van Citters. Guerrette is currently pursuing a graduate degree at Thayer, while Niparko works as a private equity analyst for Audax Group.