Artificial lung devices

In this chapter, the use of membranes in medical devices is reviewed briefly. In terms of total membrane area produced, medical applications are at least equivalent to all industrial membrane applications combined. In terms of dollar value of the products, the market is far larger. In spite of this, little communication between these two membrane areas has occurred over the years. Medical and industrial membrane developers each have their own journals, societies and meetings, and rarely look over the fence to see what the other is doing. This book cannot reverse 50 years of history, but every industrial membrane technologist should at least be aware of the main features of medical applications of membranes. Therefore, in this chapter, the three most important applications—hemodialysis (the artificial kidney), blood oxygenation (the artificial lung) and controlled release pharmaceuticals—are briefly reviewed. 

Wo Implantable, artificial lungs exist at this time hut some research has been done on polymeric membranes that could be used In such a device. Extracorporeal blood oxygenators are, however, used In excess of 100,000 times a year (l) and contain a thin, polymeric membrane thru which O2 and CO2 are exchanged. These oxygenators, which exist in several different styles are widely used In by-pass and other operations. The main polymers used are silicone rubber but poly(alkyIsulfones) and some others show promise (l, 50, 5l). 

Certainly with the modern emphasis on artificial body replacement parts and the success of implanted bits of hardware and assist devices for the heart (valves, heart bypass and pacemakers) and kidneys (renal dialysis), a substitute device for the natural lung should be considered. Artificial lungs are used daily for short-term (3- hours) heart-lung bypas in large, specialized health care centers. These are extracorporeal... 

Since membrane lungs as extracorporeal devices are in wide use, thoughts have turned to an implantable artificial lung prosthesis based on membrane technology. Developing such a device with the adequate characteristics and long-term reliability is a much more difficult task than encountered with the extracorporeal device developed for intermittent use. However, a small prototype device made of porous Teflon has been fabricated and tested by Richardson and Galletti. ... 

Galletti, P. M. and C. K. Colton, 1995, Artificial lungs and blood-gas exchange devices, in The Biomedical Engineering Handbook, J. Bronzino, ed., CRC Press, Boca Raton, FL, pp. 1879-1897. 

Healthcare and hygiene textiles Extracorporeal devices Bedding, protective clothing, surgical gowns, clothes, wipes, etc. Artificial kidney, artificial liver, artificial lung, bioreactors, etc. 

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