Bioengineering Students Develop Better Cystic Fibrosis Treatment for Patients On-the-Go

The Resonair teamThe Resonair team (from left to right) at the annual meeting of the Biomedical Engineering Society: Elvis Ikwa, Allison Mateo, Kevin Bui, and Justo Caballero with Biodesign faculty member Ross Venook. Not pictured: Shivani Torres.

Can five undergraduate bioengineers develop a solution to address one of the most challenging problems in the treatment of cystic fibrosis? That’s what one group of students in the Biodesign Capstone course committed themselves to finding out. In this two-quarter course, senior bioengineering students are challenged to identify and comprehensively understand an unmet healthcare need and apply their engineering skills and expertise to develop a viable solution to address it. In this case, Kevin Bui, Justo Caballero, Elvis Ikwa, Allison Mateo, and Shivani Torres became intrigued with the treatment of cystic fibrosis (CF) and decided to further investigate healthcare challenges in this space.

CF is a chronic disease marked by excessive secretion of thick mucus in the airways. Its treatment requires patients to clear the airways several times each day, most often through manual chest percussion therapy. Because this regimen is time-intensive, uncomfortable, costly, and often requires going to a care center, one of the biggest problems in CF treatment is compliance. “Patients with low treatment compliance attribute it to the large amount of time and effort it takes every day,” said Mateo. “But lack of compliance exacerbates the accumulation of mucus, making the lungs more susceptible to infection, which increases hospitalizations and lowers life expectancy.”

Interested in the issue of poor patient compliance, the team focused on better understanding the patient experience. They researched CF, read patient blogs, and reviewed journal articles. They also spent as much time as possible talking to patients, doctors, and nurses at the Stanford Cystic Fibrosis Center. “The Biodesign program teaches students to gain insights and build empathy by talking directly to the people who are involved,” noted Torres. “The best way to gain insights for any problem/need is to go straight to the source, hear about an individual’s life, comprehend their day-to-day challenges, be observant, curious, and ask why -- shamelessly.”

Based on the insights they gathered, the team envisioned making CF treatment less time-intensive and more user-friendly (and potentially less painful), especially for those who are active and on-the-go. They wanted to develop a device that was portable, passive, and discreet in order to address the most common concerns affecting patient compliance. “We came up with the idea of using small motors placed against the patient’s back that would create a vibrational force that resonates at the frequency of the lung, and would have the same effect as percussive treatment,” Torres said. Inspired by this concept, the students adopted the team name “Resonair.”

To prove that a portable solution was viable, the students conducted bench top experiments with mucin proteins to recreate the mucus characteristics of CF and measure its response to vibrations. “Another challenge was figuring how much force/frequency would propagate to the lungs from vibrations administered on the surface of the back of the patient,” recalled Torres. They addressed this through an ex vivo experiment for which they developed a custom measurement system and protocol.

The next step was developing the form factor of the solution. “In the beginning, it was difficult to pinpoint the exact route we wanted to take,” said Caballero. “There were lots of ideas that were feasible, but what helped us move forward was getting away from hypothetical thinking and actually starting to sketch and construct early prototypes.” Added Bui, “A lot of times, people can get lost in trying to plan out the perfect project at the beginning and lose valuable time trying to overthink things when the best way to proceed is to just build it and see what happens. The most useful feedback we got was from designing experiments, building prototypes, testing the product against our design specifications, and learning from our observations.”

Through this approach, the team came up with its final design, an ordinary-looking backpack fitted with four small, individually adjustable motors, permitting relative comfort as well as portability and discretion. This creative solution to a challenging problem was recognized with a $10,000 third place award at the National Institute of Biomedical Imaging and Bioengineering DEBUT (Design by Biomedical Undergraduate Teams) competition. Buoyed by this support, the students performed some preliminary efficacy and outcomes testing on the device, but ultimately put the project on hold to pursue other professional endeavors, including medical school, graduate school, and positions with Bay Area health technology companies.

Shivani Torres demonstrates how the team’s prototype is worn.

While the Resonair device is not yet helping patients, each member of the team realized great benefits from this open-ended, real-world design challenge. “I would equate the experience to working as an entry-level engineering or research assistantship at a biomedical engineering company,” said Torres. “It was eye-opening to learn about project management, self-directed R&D, and communicating research findings to a board of advisors.” Added Ikwa, who subsequently joined an early-stage biotech start-up, “The course prepared me to contribute across the organization because I have experience understanding a challenge from multiple perspectives and driving it all the way to a tested prototype.”

Another key learning was the importance of seeking direct input from end users. As Torres explained, “The key to the success of your device, technological feasibility aside, is to make sure it addresses the real needs of the people you want to help. Instead of speculating how a technology may be used, you'd be surprised at how candidly people will give you their opinions. As a medical device designer, there’s nothing more powerful than giving someone a set of really early-stage prototypes, and then having them give you their unprompted and honest thoughts and reactions.”