A Department of Veterans Affairs (VA) research team, in collaboration with Old World Labs — a company in Hampton, Virginia, specializing in high-resolution 3D printing — is working to build a prototype of a wearable artificial lung that could be compatible with living tissue and able to provide short- and long-term respiratory support.
Sized to fit into a backpack or waist pack and with potential use of more than a week, the small-scale functional prototype is expected to be ready in the upcoming months. The next step is to test it in animals before it can be used in patients.
According to Joseph Potkay, PhD, lead researcher of the project and a biomedical engineer at the VA Ann Arbor Health Care System in Michigan, this will be the first attempt to use high-resolution 3D polymer printing to create functional microfluidic lungs with three-dimensional blood flow networks.
This microfluidic artificial lung is a new class of artificial organ that mimics the overall structure and blood flow of the natural organ better than other standard artificial strategies.
The microfluidic 3D structure will be combined with a biocompatible coating that can prevent the immune system’s reactivity and organ rejection, as well as allow improved interactivity of the artificial lung and one’s natural tissues, increasing the lifetime of the device.
“The flexibility in design afforded by 3D printing gives us more freedom and thus the ease to build artificial lungs with a small size and pressure drops that are compatible for operation with the body’s natural pressures,” Potkay, who is also a researcher at the University of Michigan, said in a VA research news release.
With a focus on treating COPD, in 2011 the team developed a 2D-printed artificial lung that aimed at reducing CO2 levels, often increased in these patients because of impaired airflow. Using silicon tubing and an ultra-thin membrane that allowed efficient gas diffusion, the device could use air as the ventilating gas, as opposed to pure oxygen stored in a tank, as standard systems do.
COPD is one of the most prevalent and costly diseases among veterans, affecting 16% of the veteran population and about 5% of American adults.
The 2D project is ongoing, with the device currently being tested in rabbits. The team is pursuing the next stage of funding to advance the 2D lung up to sizes that could be used in people.
“Although the 3D artificial lung is more promising, it is earlier in development and still not guaranteed to work,” Potkay said. “We’re further along in developing the 2D device, and we have plans to work around the challenges with that device.”
The team has plans to test its high-resolution 3D-printed artificial lung in a large animal model, most likely a sheep.
Besides helping COPD patients, the researchers say the artificial organ could be a temporary strategy to help patients waiting for a lung transplant, or those whose lungs are healing. They expect that future versions could have longer-term applications.