Anyone who’s blown bubbles for a child has probably marveled at the ability of a sticky, soapy bubble to trap air.
A team of researchers in Nebraska and Colorado has been working for several years to take that concept a step further and create a kind of liquid lung in the abdomen. They believe that a froth of tiny bubbles — aka microbubbles — could deliver oxygen to patients with life-threatening lung conditions.
Their initial focus is creating a simpler, more portable way to help Air Force personnel who suffer traumatic lung injuries in remote areas, while they’re en route to a hospital.
Dr. Keely Buesing, a University of Nebraska Medical Center assistant professor of surgery, said the researchers also are seeking a way to provide oxygen to hospital patients who aren’t doing well on a ventilator.
In the first few weeks after a severe lung injury, the organs often don’t function well, said Buesing, a trauma surgeon at the Nebraska Medical Center.
Using a ventilator to supply oxygen, while standard practice, poses a risk of injuring the lungs, especially when the machines are used at higher oxygen and pressure settings. The lungs can toughen and stiffen, limiting their ability to exchange oxygen and carbon dioxide.
If the doctors instead could provide oxygen via microbubbles during those early days, they could avoid that problem and allow the lungs to rest.
“The lungs are an amazing organ that can heal itself. It just needs time. That’s the idea, is to buy some time,” said Mark Borden, an associate professor of mechanical engineering at the University of Colorado Boulder.
The microbubbles, with a diameter about 1 percent the width of a human hair, are designed to mimic the function of the tiny sacs in the lungs, which release oxygen and pick up carbon dioxide, said Borden, who spent his early years in Omaha. When delivered into the abdomen, or the chest cavity, the microbubbles, concentrated in a liquid foam, could function like a third lung.
Ideally, Buesing said, such a system could replace ventilators and provide all of the oxygen a patient needed.
Benjamin Terry, a University of Nebraska-Lincoln associate professor of mechanical and materials engineering, is working on a medical device that would pump fresh foam in and spent foam out.
Borden also is working on a powdered form of the microbubbles that could be reconstituted in the field. Currently, the foam is transported in glass containers, which could be a safety hazard on a military mission.
Terry and Buesing are testing microbubbles in animal models in preparation for moving on to humans, which still is several years off, Buesing said.
Buesing said they are seeing improvements in oxygen saturation levels that could be enough to raise oxygen levels in an injured person from dangerously low to life-sustaining.
The Department of Defense Office of the U.S. Air Force Surgeon General recently awarded a two-year, $3.7 million contract to the National Strategic Research Institute at the University of Nebraska to advance work on the potentially lifesaving system.
The institute received its first Defense Department contract for the project in 2016. The researchers also are collaborating with the Strategic Command at Offutt Air Base and the Center for Advanced Surgical Technology housed at UNMC.
As a trauma surgeon, Buesing said, the work is exciting on a personal level. She and other physicians are frustrated and saddened when they have to tell families that there’s nothing more they can do.
“We have to see whether it will work and how well it will work,” she said. “Those studies are yet to be done, but it has potential.”