Artificial lungs in a backpack may free people with lung failure


Engineers at the University of Pittsburgh developed an artificial lung that can be carried in a patient’s backpack. So far, this device has been shown to work in sheep. It’s one of several such devices being developed that could transform the lives of people with lung failure and offer them relief and mobility. The new device still requires an oxygen tank to be wheeled around, although tank-free prototypes are also being tested.

Artificial lungs could provide a stopgap for people recovering from severe lung infections or waiting for a lung transplant – although a transplant would still be a better long-term solution for those with permanent lung damage.

Usually, people with lung failure are connected to a machine that pumps their blood through a gas exchanger to provide oxygen and remove carbon dioxide – but this often confines them to bed. The longer they are bed-ridden, the weaker their muscles become and the less likely they are to recover. Interest in better options grew after the 2009 swine flu outbreak, when many patients ended up on this kind of support.

“The disparity between the number of patients that need lung transplants in the availability of lungs to be transplanted means that many patients can wait months for a donor lung,” William Federspiel, University of Pittsburgh who leads the team developing the device, told Digital Trends. “The literature on lung transplants is very clear in that if patients can be mobilized while they wait for a donor lung, the post-transplant outcomes are better.”

Federspiel’s team has developed an artificial lung that combines the pump and gas exchanger into one device that’s small and light enough to be carried in a backpack, making walking easier.  The device would be connected to the patient’s neck, requiring just a short tube. “We want very little tubing that runs outside the body,” says Federspiel. The results from this study are published in The Journal of Heart and Lung Transplantation.

Another kind of artificial lung is under development at Carnegie Mellon University in Pittsburgh. However, it is designed for patients whose hearts are working well enough to pump the blood through the gas exchanger. Work due to be published later this year showed it kept three out of four sheep alive for two weeks.

Both these devices require an oxygen supply – so any human patient would still have to wheel around an oxygen tank, but they would be far more mobile than they are currently.

A far more efficient device is in the works that utilizes the air in a room, so no cylinder is required. This runs blood through extremely thin channels formed by polymer membranes, providing a larger area for gas exchange.