Investigations
Warm storage for donor organs
With 77,860 Americans awaiting organ donations, no transplant surgeon wants to hear that a kidney or liver is unusable. Nonetheless, David Cronin, PhD'97, was excited to learn in early November that one such liver-containing 70 percent fat and therefore unsuitable for recipients-had made its way to the University of Chicago Hospitals. This was Cronin's first chance to keep a human liver alive outside the body using a new warm-storage device. The machine, which he's developing with TransMedics Inc., could ease the frenzied pace of organ transplantation, giving surgeons the chance to monitor and repair organs that have lived long lives or are stressed from their donor's death.

Cronin, an assistant professor of surgery, placed the liver in a plastic case atop the Portable Organ Preservation System, a battery-powered machine about the size of a dorm refrigerator. For about 24 hours, doctors monitored the organ while the machine pumped a warm solution of electrolytes, vitamins, and nutrients through it. The liver processed the fluid and created bile, just as it would inside a human.

In a normal transplant situation, the liver would be sitting on ice-not producing bile and, even worse, sustaining damage as the hours ticked by. "The problem [with traditional ice storage] is that there is no oxygen in that environment, and you get cell death," Cronin says. "The longer organs are on ice, the more damage they sustain."

The machine could also grant surgeons valuable time. "We're always racing to take the organ, to transport it, to transplant it," Cronin says. "A patient receiving a heart or liver that doesn't function may not get a second chance. This system allows us to see that the organ is functioning and perhaps even repair it."

After three years of tests on nearly 500 animal organs, Cronin first kept an unusable human kidney alive on the device this past August. That organ also functioned for 24 hours-and that's plenty of time, he says.

The machine is slated for clinical trials on kidneys within the next year, followed by tests on hearts, pancreases, small intestines, and lungs. Even since August the machine has been greatly improved. "It's portable, lighter, and smaller," Cronin says. "We can put it in the back of a van or on an airplane."
-S.A.S.

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