Eggbeater-like device could bust bladder blood clots

"I think the first question is, 'Is that thing really going into my urethra?'"

So begins the Rice University video below in which student Aaron Hu imagines what patients might think if they saw a doctor coming at them with what looks like a modified fishing pole bearing an eggbeater at the end.

The answer, of course, is: "Yup, that's exactly where it's going!"

The scenario could play itself out in hospitals one day as a team of five bioengineering students at Rice continue to develop a clot buster they created as part of a senior engineering project.

Their device uses a hand-cranked spindle to turn an eggbeater-like head at the other end of a line. The line would be fed through a catheter into the bladder, where it would create a vortex that would suck clots toward the whipping wires and destroy them. According to the group of students, known as Team Evacuator, the process is superior to other methods currently used to dissolve bladder blood clots. These include surgery and/or a saline flushing process that Lung-Ying Yu, one of the students involved in the project, likens to "sucking Jell-O using a straw."

The wire-like blades at the end of the device, which one student refers to as a "clot slayer" in the Rice video, are made from nitinol, a nickel-titanium alloy that deforms and rebounds easily. This means the wires can collapse while traveling through a catheter to the bladder and then open up once inside.

In the demonstration video, Adrian Gallegos, another student involved with the project, uses a cup of liquid holding a blob of Jell-O inside to show how the device would whip away clots, saying the process takes "not even a minute" to dissolve the lump of gelatin.

Although the prototype "clot slayer" is a manual version that requires one hand to hold the device and another to crank the handle, the team is working on a battery-powered option. When complete, it should be able to be operated with one hand and will incorporate both forward and reverse oscillations, something the team observed as being more effective in dissolving clots.

The students estimate the device will cost about $20, which, along with its simple operation, would lower the barriers to uptake by the medical community, Nadeem Dhanani, project mentor and assistant professor of surgery in the Division of Urology at the University of Texas Health Science Center, said in a statement.

Blood clots in the bladder can be caused by conditions ranging from urinary tract infections to cancer, and can block the passage of urine, leading to kidney failure. "For us to be able to come up with a device that successfully breaks blood clots up into small slivers, I think that's a very big step forward when it comes to medical devices in this area," Hu said.

In addition to Hu and Gallegos, the team includes Patrick Yun, Tiffany Huang, and Lung-Ying Yu. Their next step will be getting the device ready for animal trials. That, and graduation.