To date, over 120,000 individuals await for life-saving organ transplants in the U.S. but there are a number of challenges associated with the procedure. Besides the scarcity of donors relative to the number of people who need to replace their damaged or absent organ, time is literally gold when it comes to transporting donated organs.

Outside the body, organs can't stay alive for too long. The typical storage time for kidney, for instance, is 30 hours or less and much shorter for the heart and lungs with only less than six hours before they start to deteriorate. Once an organ becomes available, doctors rush to get it from the donor to the recipient as fast as they can. Unfortunately, there are times that an organ does not make it to the supposed recipient "alive."

A new cooling technique developed by researchers from the U.S. and the Netherlands, however, can preserve organs for days and this can potentially improve organ transplantations and even boost organ donation. The cooling method known as supercooling involves chilling the tissue while pumping nutrients and oxygen into the blood vessels.

For their study "Supercooling enables long-term transplantation survival following 4 days of liver preservation" published in the journal Nature Medicine on June 29, Korkut Uygun, from the Harvard Medical School in Boston, and colleagues, showed how the supercooling technique allowed livers to remain viable for several days.

In an experiment with rat livers, the researchers used a machine to deliver oxygen and a nutrient solution that consist a glucose compound and an anti-free agent to the organ tissues to prevent them from freezing and damage as well as to protect the cells. They then cooled the organs to 21 degrees Fahrenheit. The researchers then rewarmed and prepared the organ with the machine once it was ready for use. Using the technique, the researchers were able to store the liver for up to four days.

All of the 12 rats that were transplanted with the livers that were stored using the supercooling technique survived for three months while all of the rats that were transplanted with liver that did not go through the same cooling procedure died.

"We show here that 100 per cent survival is limited to 72 hours of storage, as the survival drops considerably, to 58 per cent, when the storage time is extended to 96 hours," Uygun said.

Uygun said that the results of the study can pave way for donated organs to be shared from anywhere in the world. Further tests, however, are still required to see if the method that was tested on rat livers can work for humans as well.