Posted on 12/18/2010 8:34:36 AM PST by neverdem
Artificial lung technology could reduce the death rate for patients awaiting a lung transplant, say US scientists.
Advanced lung disease is characterised by an inability to remove carbon dioxide from the blood and reduced oxygen uptake efficiency. A shortage of donors can mean long delays and high mortality rates for those awaiting a transplant. The only technology available to aid sufferers during this time is based in intensive care units, hindering quality of life.
Now, Joseph Vacanti and coworkers at Massachusetts General Hospital, Boston, have developed a device that achieves the CO2/O2 gas exchange that, when implanted in the body, could allow patients more freedom when awaiting a transplant. Their design is a microfluidic branched vascular network through which blood flows, separated from a gas-filled chamber by a silicone membrane less than 10um thick. The network is formed by casting polydimethylsiloxane, a biocompatible polymer, on a micro machined mould.
|
A device that achieves carbon dioxide/oxygen gas exchange could allow patients more freedom when awaiting a lung transplant
|
A major challenge faced by Vacanti's team was achieving a blood pressure within the device's channels similar to that in veins and arteries. They applied computational fluid dynamics to optimise the vascular network's structure to avoid clotting induced by excessive blood pressure. 'Fulfilment of these design criteria necessitated creating channels that had variable depth throughout the network and also had precise curvature,' says Vacanti's coworker, David Hoganson.
Vacanti's device could be scaled up for implantation. According to Hoganson, an implant-sized device could be fabricated by 'stacking the functional layers of the device to achieve the necessary surface area for gas exchange'.
Jaisree Moorthy, who specialises in using microfluidics in tissue engineering at the University of Pennsylvania, says that Vacanti's device provides a very elegant solution. Compared to existing devices, Moorthy comments that it 'is more efficient due to a thinner membrane, and mimics the biological CO2/O2 transfer rate'.
In the future, Vacanti hopes to develop the device further to incorporate engineered lung tissue.
Lung assist device technology with physiologic blood flow developed on a tissue engineered scaffold platform
David M. Hoganson, Howard I. Pryor II, Erik K. Bassett, Ira D. Spool and Joseph P. Vacanti, Lab Chip, 2011
DOI: 10.1039/c0lc00158a
Wibbly wobbly diagnostics for lung disease
A jelly-like substrate is being used to detect nitric oxide in exhaled breath, a telltale sign of diseases like tuberculosis and lung cancer
Nanoparticle breath test for lung cancer
A gold nanoparticle sensor can quickly and easily distinguish between the breath of lung cancer patients and healthy individuals
Breathe easy for cancer diagnosis
A painless breath test can identify trace gases emitted by malignant cells
Hmmm. Looks more like a gill than a lung.
I’d also be willing to bet that the same basic design with different materials selections would work as a kidney.
Probably. It appears that all higher organisms have genes coding for the biophysical phenomena of fractals, e.g. arterial branching down to the level of capillaries.
Real Time Translating App for your Phone (vanity-amazing video, translates language as you watch)
Berlin Patient Follow-Up 'Strongly Suggests' HIV Cure "Berlin Patient" is an American.
Pitt study finds NSAIDs cause stem cells to self-destruct, preventing colon cancer
FReepmail me if you want on or off my health and science ping list.
I knew a woman who, when she died, was the oldest living lung transplant. She made it about 10 years.
This is just a cross-exchange at a membrane. There are literally thousands of applications, from water purification to generation of oxygen-enriched gas (for people who suffer from lung/heart insufficiences) to generation of nitrogen-enriched gas (for food preservation), to kidney dialasys, and on and on.
The key is to find materials that won't cause the blood to clot, and which won't degrade in performance or plug up over time. But satisfying those requirements is "nontrivial" to say the least.
Disclaimer: Opinions posted on Free Republic are those of the individual posters and do not necessarily represent the opinion of Free Republic or its management. All materials posted herein are protected by copyright law and the exemption for fair use of copyrighted works.