Researchers create artificial lung that works with air rather than pure oxygen

Researchers create artificial lung that works with air rather than pure oxygen
The artificial lung filled with breathable silicone rubber 'blood vessels' (Image: Joe Potkay)
The artificial lung filled with breathable silicone rubber 'blood vessels' (Image: Joe Potkay)
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The artificial lung filled with breathable silicone rubber 'blood vessels' (Image: Joe Potkay)
The artificial lung filled with breathable silicone rubber 'blood vessels' (Image: Joe Potkay)

Researchers have created an artificial lung that uses air as a ventilating gas instead of pure oxygen - as is the case with current man-made lungs, which require heavy tanks of oxygen that limit their portability. The prototype device was built following the natural lung's design and tiny dimensions and the researchers say it has reached efficiencies akin to the genuine organ. With a volume roughly the same as a human lung, the device could be implanted into a person and even be driven by the heart.

The artificial lung is filled with breathable silicone rubber versions of the blood vessels that branch down to a diameter less than one-fourth of human hair. It was created by first building a mould with miniature features and then layering on a liquid silicone rubber that solidified into artificial capillaries and alveoli. They air and blood channels were then separated with a gas diffusion membrane.

By making the parts of the artificial lung on the same scale as the natural lung, the researchers say they were able to create a very large surface-area-to-volume ratio and shrink the distances for gas diffusion compared to the current state-of-the-art. In comparison to current artificial lung systems that require pure oxygen due to their inefficient oxygen exchange, tests of the new artificial lung using pig blood showed a three to five times improvement in oxygen exchange efficiency over current devices. It is this efficiency that enables the new artificial lung to use plain air instead of pure oxygen as the ventilating gas.

Blood is injected into the device's fluid inlet, while air is fed into the gas inlet. Oxygen molecules diffuse across the gas exchange membrane into the blood on the way to the blood outlet, while carbon dioxide in the blood fed into the device would diffuse across the membrane to be released through the air outlet.

"Based on current device performance, we estimate that a unit that could be used in humans would be about 6 inches by 6 inches by 4 inches tall, or about the volume of the human lung. In addition, the device could be driven by the heart and would not require a mechanical pump," said Joe Potkay, a research assistant professor in electrical engineering and computer science at Case Western Reserve University.

Potkay says the device is a major step towards an easily portable and implantable artificial lung and the team envisions patients using the technology while allowing their own diseased lungs to heal, or implanting one while awaiting a lung transplant.

Potkay's team, which includes Brian Cmolik, MD, an assistant clinical professor at Case Western Reserve School of Medicine, and Michael Magnetta and Abigail Vinson, biomedical engineers and third-year students at Case Western Reserve University School of Medicine, is now collaborating with researchers from Case Western Reserve's departments of biomedical engineering and chemical engineering to develop a coating to prevent clogging in the narrow artificial capillaries and on construction techniques needed to build a durable artificial lung large enough to test in rodent models of lung disease.

The Case Western Reserve University researchers expect to have human-scale artificial lungs in use in clinical trials within a decade.

Racqia Dvorak
Faster, stronger, better....
We\'re getting there, folks...
This looks identical in principle to something I\'ve been thinking about, which would work to extract oxygen from water, not air ... in other words, a human gill system.
Ideally it would be externally mountable, and effectively \'plug in\' to the circulatory system. It would probably need to be powered, both to push water through the \'organ\' and to ensure that the water is warmed up.
Anybody know of anyone looking at anything similar(ly crazy?)
@ Nickov8 Sorry, full marks for thinking outside the square, and maybe there are such ways of harvesting oxygen from water but for this application there are so many objections that no comment should really be necessary. Maybe the basics suffice, a gill breather lives in water, a lung breather lives in air. trying to replace one medium with the other flies in the face of portability, practicality, and.....evolution. Ian Colley.
Denis Klanac
TexByrnes animals like the cat fish which have a primitive lung and gills do exist, they can exist in stagnant low oxygen ponds by taking in gulps of air using their primitive lung.
Point taken Denis, but [a] they have both, and [b] they just \'exist\' rather than \'live\'.
Hey Tex. Where does a scuba tank sit on your list of portability, practicality and evolution? It\'s big, heavy, complex and massively dangerous. That\'s the benchmark.
A mechanical gill can - at least in theory - manage the blood/water interface to pass dissolved oxygen inband dissolved co2 out. Fish have been doing it for hundreds of millions of years. Air lungs are probably less efficient, in fact.
If using one could mean reduced dangers of bends etc from breathing highly pressurised gases, and remove time limits associated with having to carry oxygen with you, then even if the device was bigger, heavier and clumsier than a scuba tank it would have plenty of applications. However, avoiding need for pressurisation could well enable something that is actually less problematic to handle - once you get over the primitive \'gross out\' associated with blood/machine interface ... Likely to see a lot more of that as cybernetic developments come into mainstream
So - I readily admit the idea\'s crazy, but I think it deserves a little more consideration than you so generously allow it.
Also - what have you got against lungfish? They could be having a great time down there in the mud!
Denis\' point is very valid. One of the key questions is whether you can have both a gill and a lung at the same time. Lungfish are a great example. Thanks Denis!
I\'m a recently discharged navy nuclear engineer. I recently found out that my 20 year old brother is dying of a mixture of Infezema and another lung disease that fills the air sacks with mucus. The disease is attacking his lungs aggressively and this past week we were told he only has 50% function left of his lungs. My stepdad, his father died of the same disease when I was 11. My stepdad received a double lung transplant and that\'s the outlook for my brother as well. Question, if the project lead for this lung actually reads this, would it stupid to gamble on this artificial lung rather than accepting transplanted lungs that his body will most likely reject within the next few years? If so, who could prevent my brother from making this kind of choice for his life? (rhetorical question). My brother feels the same as I do. I\'d rather go down pioneering medical science that could not only save my life, but other people\'s lives in the future rather than taking a transplant that just prolongs his existence.
OK, where are they? We have already got newer, better materials since 2011.
I am in serious problems and could really do with this tech to reach market before I die. I thought of a potential stopgap solution. Fit one of the new oxygen from air systems they've developed and fit externally for mid level damage 46% (47yrs old) damage as in my lungs (misdiagnosed pneumonia). Then when I needed to run from a dangerous animal, the system fitted to outside of body could purify oxygen and saturate blood. When I walk the system can go to "Sleep mode" saving power for times of great need. Sound good to anyone, oh and I can be the guinea pig test subject for SEAL teams to have gills fitted too.
Only a quick thought I had recently, as if a cheap, easy idea comes out, I'm more likely to get one before I checkout. lol