Organ Donation: An Advancing Science Hindered by Supply Shortages

June 30 -- SUNDAY, June 29 (HealthDay News) -- More than 98,000 Americans are clinging to life this very second, and their only chance for survival is a dead person's generosity.

The science of organ transplantation has improved by leaps and bounds. But despite the advances, almost 7,200 Americans died in 2005, waiting for a replacement organ that never arrived, according to the U.S. Health Resources and Services Administration.

"The success of the clinical side is phenomenal," said David Fleming, executive director of Donate Life America, a nonprofit alliance of national and local organizations dedicated to promoting organ donation. "Unfortunately, it's not a medical problem we're looking to solve. It's truly a matter of just not having the supply that we need."

The waiting list for donated kidneys is longest. Almost 75,000 patients are waiting for a kidney, or about three of every four people waiting for an organ.

That's generally because a person without a kidney can be kept alive longer, Fleming said. Dialysis can sustain them, while patients in need of such vital organs as hearts or lungs often die quickly.

However, the nation's diabetes epidemic is expected to make kidney failure much more prevalent in the future, leading to even greater demand for donated kidneys, Fleming added.

The waiting list for livers is next longest, with more than 16,000 patients awaiting help. More than 2,600 people are waiting for a heart, while an estimated 2,100 people need a lung, and around 1,600 patients are waiting for a pancreas.

The main problem with supply is that donors must die in a very specific way for their organs to be useful to others.

"In order to donate a solid organ, you have to die a brain death," Fleming said. "It's a very small percentage of the population that die in a way that leaves them brain dead," he said, about 1 percent of deaths annually, between 20,000 to 30,000 people.

Of those who die under optimal conditions, only about 60 percent have consented to donate their organs, he said.