New 'microbubble' technology could save lives on battlefield, home front

Published: Nov. 22, 2016

Mark Borden Lab in Mechanical Engineering department at the University of Colorado Boulder.

Mark Borden Lab in the mechanical engineering department at the University of Colorado Boulder.

A new technology now under development by researchers at the University of Nebraska and the University of Colorado Boulder could result in the creation of a so-called “third lung” for severely injured patients that could keep them alive until arrival at a hospital.

The research project is funded by a $1.3 million contract from the United States Air Force (USAF) Surgeon General Office to the National Strategic Research Institute (NSRI) at the University of Nebraska. The goal to advance a new medical treatment that will provide oxygen to patients whose lungs cannot function efficiently due to trauma.

The award was made to the NSRI to use “microbubble oxygenation,” an emerging technology the researchers hope will provide rapid oxygen delivery to injured patients, which would result in adequate levels of blood oxygen during emergency transport from remote environments far from hospitals. The support of the USAF Surgeon General Office contract will move the research forward in three significant directions at the two universities.

CU Boulder Associate Professor Mark Borden of mechanical engineering and inventor of the oxygen microbubbles will create both a process and system capable of large-scale manufacturing. University of Nebraska-Lincoln Assistant Professor Benjamin Terry of mechanical and materials engineering will design and develop a medical device to deliver oxygen microbubbles to patients. Dr. Keely Buesing, assistant professor of surgery at the University of Nebraska Medical Center, will develop injury models for testing the new technique.

Invention born at CU Boulder

Terry, a former CU Boulder graduate student in mechanical engineering, and Borden invented the new way of administering oxygen to patients who cannot breathe.   

“I was struggling because it seemed too risky to do a direct intravenous injection of such a large volume of the microbubbles, recalls Borden.  “Ben brought his expertise in noninvasive surgery, where it is commonplace to inflate the peritoneal cavity to allow space to move the laparoscopic instruments.  The peritoneal oxygenation concept was born in this conversation—the proverbial light bulb went off brightly above our heads.”

“Our system transforms the abdomen into a third lung, so to speak,” Terry explains. “Through a method of pumping and delivering oxygen microbubbles into the abdomen while removing dangerous carbon dioxide, the process delivers life-sustaining oxygen to the body's core, which is then circulated to the brain and other vital organs.”

Borden says the team members are taking a “biomimetic” approach—learning as much they can from nature on how to solve the engineering problem of delivering vital oxygen to the body's tissues.

Tiny bubbles that could save lives

Microbubbles are tiny bubbles, each one only a fraction of the size of a human hair, that are designed to mimic the alveoli in the human lung by releasing oxygen to the body and simultaneously removing carbon dioxide, said Borden.  Each cubic centimeter of microbubble foam contains trillions of individual microbubbles, providing an enormous surface area for the gas exchange process to take place. 

“Once the oxygen has been delivered, the spent microbubbles can be safely removed from the peritoneal cavity within the abdomen,” said Borden. “So we do not anticipate any long-term toxicity.”

Buesing said that major combat-related trauma produces severe injuries, some of which affect the lungs, resulting in life-threatening or fatal lack of oxygen to the body.

In some cases, the lungs are so damaged that ventilation is inadequate and injured soldiers must be transported, sometimes long distances, to advanced hospital facilities, Buesing says.

As part of the project the CU Boulder team will work on scaling up the manufacturing processes to rapidly generate oxygen microbubbles in large quantities for long-term storage and transport to the site of need. 

“This is a unique engineering challenge,” says Borden. “The goal is to bring a technology from the benchtop scale to mass production.”

Through this research, the USAF Surgeon General Office is aiming to further technology and procedures for increasing the survival rate of injured patients so they can reach the most capable treatment, recovery and rehabilitation facilities.