Lung failure is typically addressed through the use of mechanical ventilation, but potential complications include collapsed lungs, airway injury, and diaphragm atrophy. An alternative is extracorporeal membrane oxygenation (ECMO), where blood is circulated outside of the body, undergoes gas exchange in an ‘artificial lung’, and is returned to the patient. The major shortcoming of extracorporeal oxygenation is that it can be complicated by blood clotting, and thus, in anticipation of this risk, patients must take blood thinners which carry risks of their own.
Draper Laboratory has created a microfluidic oxygenator that uses the same procedure as extracorporeal oxygenation but does not promote clotting. In Draper’s solution, the traditional ‘artificial lung’ is replaced with a cassette made up of a stack of biocompatible plastic layers patterned with microfluidic channels. The internal fluid path of the cassette is designed such that it contains only gradual changes in diameter and avoids any sharp corners or other geometry that may cause blood to clot, much like the blood vessels in the body. This solution allows for high blood flow rates and much more efficient gas exchange. A flow rate of 100 milliliters per minute has already been achieved with bovine blood, and the goal for the final design is to treat liters of blood per minute.
The team plans for the device to be ready for human use in three years. Down the road they believe this technology could be successfully used for other applications like kidney failure and drug delivery.