Breathe Easier: Artificial Lung May Soon Be Reality
"What we are doing is intercepting the blood before it arrives in the lungs," says Hattler. "We can add oxygen and remove carbon dioxide while letting the lungs rest."
He explains that external controls regulate the amount of oxygen supplied as well as the rate at which carbon dioxide is vacuumed out of the blood.
Hattler says that although this device is the first major breakthrough in artificial lung technology, it does build on earlier technology.
Several years ago a venture capital company introduced the concept with IVOX, a device that supplies oxygen to the veins. That product was "actually tested in humans," says Lyle Mockros, PhD, but it was eventually abandoned when the developers ran out of money. Mockros is a professor of biomedical engineering at Northwestern University in Chicago.
Mockros says his group at Northwestern, as well as a third team at the University of Michigan, are concentrating their efforts on developing a more permanent artificial lung that could be used longer-term while a patient waits to get a lung transplant, says Mockros. Current work is focused on devices that are wearable and are attached to the patient.
Physicians have been trying to adapt the heart-lung machine for use as an artificial lung for people with severely damaged lungs, such as people with severe emphysema, Mockros says, but efforts have not been successful.
The difficulty in developing a successful artificial lung is that the lungs, he says, have a large surface area and devices that mimic them also have a large surface area. When blood passes over a large artificial area, it can be damaged in a way that causes the formation of blood clots. Designers seek to overcome this risk by giving patients powerful anticlotting drugs, but those can lead to unintended bleeding.
Hattler's device is much smaller, so the surface area is less, and the anticlotting drug heparin has actually been built into the device. This approach reduces the risk for clot formation, Hattler says.
If Hattler's device is successful in human studies, Mockros says it will be a major advance in the world of artificial lungs.