Undergraduate Bioengineering Students Address Real-World Medical Problems in Senior Capstone Design Course

Back in 2004, the first students were accepted into Stanford’s brand new Bioengineering department. Ever since, the department, which is jointly supported by the Schools of Medicine and Engineering, has been growing steadily. Today, nearly 30 undergraduates complete their bioengineering degrees each year (along with a handful of Master’s and PhD students). Through the program they receive advanced training in both engineering and life sciences to equip them to tackle challenges affecting living systems, many in the medical field.

Undergraduate bioengineering students spend a fair amount of time mastering basic science and core engineering concepts during their time at Stanford. But they also have the opportunity to apply what they’re learning through innovative classes like the Bioengineering Senior Capstone Design course. This two-quarter offering, which is led in part by Stanford Biodesign faculty, enables seniors to use all of the research skills and bioengineering expertise they’ve gained to tackle a real-world need. “The idea is to give these students a culminating experience that reinforces and integrates what they’ve learned while also preparing them for what it’s really like to work as an engineer,” explains Ross Venook, Assistant Director of Engineering for Stanford Biodesign and a Lecturer in Bioengineering.

Working in small teams, students in the Capstone course select a scenario that describes a less-than-ideal healthcare situation. Next, through background analysis and first-hand interviews with healthcare practitioners, patients, and other stakeholders, the team members delve into the problem and identify specific pain points in the care cycle. Through a screening process, they ultimately decide on a single compelling need to address. With guidance from both instructors and industry mentors, the team then seeks to invent, prototype, and gather proof-of-concept evidence for a potential solution.

In following this process, students are often pushed out of their comfort zones. As one student, Chris Mathy, describes, “High-achieving students tend to get nervous when they can’t find the right answers quickly. They’re uncomfortable with ideas that fail, and don’t want to take the time to mull things over. There’s a misconception that innovators just wake up one day with a ‘eureka moment,’ but this course makes it clear that innovation is an active process of discovery that takes the right people, the right resources, and asking the right questions at the right time.”

Students in the Capstone course also learn practical skills that are essential for bioengineers working in industry. For instance, when Maria Filsinger Interrante took the class, one of her key takeaways was how to design experiments that result in quantifiable data that helps de-risk and demonstrate the value of a solution. Her group, which included Katie Donahue, Danielle Fraga and Mark Kirollos, initiated a project focused on the struggles some couples have trying to get pregnant through in-vitro fertilization (IVF).

After identifying many compelling needs in this space, the team decided to focus on embryo transfer (ET), the last part of the IVF cycle, in which the physician inserts a small, flexible catheter into the uterus and delivers the fertilized embryos. The team’s insight into the problem was that, while this transfer procedure is easy and quick for many patients, it can be problematic for others due to natural anatomical variations in the position of the uterus that create sharp angles from the vaginal canal through the cervix and into uterus. In these instances, physicians must use a more rigid catheter and/or additional instrumentation such as uterine forceps to access the uterus, which can traumatize the tissue, triggering an inflammatory response that lessens the chances of a successful implantation.

To address this problem, Filsinger Interrante and her teammates developed a maneuverable catheter that facilitates successful navigation into the uterus with minimal trauma. The challenge was then to design experiments that would translate characteristics like steerability and trauma reduction into quantifiable results. “We needed to validate our solution and then be able to communicate its differences relative to the standard of care,” she remembers. Ultimately, the team developed a proxy that showed how these aspects translate to a true biological system. They then designed a conceptual representation of the IVF transfer catheter space that illustrated relative trauma and steerability for the standard of care and for their prototypes. This provided a clear comparison of how the different options performed, including the team’s final design, an innovative, sheathed drawstring catheter named Ovoflex.

Another interesting benefit of the Capstone course is that students develop and improve skills that aren’t directly related to engineering. Take Mathy and his team, for example. He and three other students, Celina Malavé, Shivani Baisiwala, and Kaelo Moahi, chose to address gastric bypass patients who experience postoperative complications. Gradually, the group honed in on surgical site infections, a burdensome problem for patients and caregivers because these wounds have to heal from the inside out, requiring a painful, somewhat gruesome process of wound packing and unpacking twice a day until the healing is complete. The team looked for ways to streamline the treatment and reduce the care burden on both patients and providers. “Our final concept solution involved the creation of an absorbable, removable hydrogel for wound packing,” describes Mathy. Dubbed Gel-Aid, the hydrogel is superior to the standard of care (gauze packing) at absorbing the fluids that drain from the wound, keeps the wound open as it heals from the inside, and can be managed by the patient at home because is easier and less painful to insert and remove.

While the project required significant technological innovation, Mathy was most impressed by how much he learned about the importance of communication. “Everyone in this class has good engineering ideas,” he says, “but the students who were able to effectively communicate are the ones who built unity around an idea, and that brought the entire team along.” Similarly, he notes, communication skills made the difference when it came time to present projects to industry experts, such as potential investors. “All of us could describe the problem and our solution,” Mathy explains. “But the most successful communicators anticipated the hard questions—the ‘yes, and…’ questions, or the questions about how the technology works in edge cases, for example. That required a breadth of perspective that wasn’t intuitive for many of us as engineers.”

While the undergraduate students in the Capstone course commit long hours and plenty of hard work to this intensive, applied learning opportunity, many describe it as the highlight of their senior year, if not their Stanford experience. As Venook summarizes, “Our goal is to provide the students with open-ended, real-world engineering experiences and opportunities for learning. This course ends up being more challenging than many students expect—and often in different ways than they expect. I am always excited to watch them embrace these challenges and grow from them. I believe they leave our program confident and well prepared for the future.”