TORONTO -- In the life-and-death world of lung transplantation, the statistics can be heart-breaking. While at least one in five patients dies waiting for a transplant, as many as 90% of donated lungs have to be discarded because the fragile organs are too damaged.
Surgeons at a Toronto hospital announced on Friday, however, that they have found a way to beat the discouraging odds with an "amazing" new procedure touted as the first of its kind in the world.
The doctors say they can now repair -- outside the body -- lungs that in the past would have been too diseased or injured to implant in another person.
The laboratory-refurbishing procedure should make many more lungs available for transplant, shrinking the growing waiting lists and cutting the number of patients who die before their number comes up, the Toronto General physicians told a news conference.
The technique involves keeping the lungs functioning at body temperature for hours using a ventilator and a bloodless solution, instead of the usual practice of storing them on ice until they are needed.
The hospital showed a brief, stunning video of one pair of lungs hooked up to the team's new system, breathing in and out as if still inside someone's body. They lie under a glass chamber -- whose design was inspired by Toronto's Rogers Centre stadium (formerly known as the SkyDome) -- that can be opened and shut to allow doctors to work on the organs.
"To see these lungs that are damaged and 12 hours later are perfect is fascinating," said Dr. Shaf Keshavjee, who headed the project. "Worldwide, this strategy could easily double the number of lung transplants that are done ... It's a phenomenally exciting advance."
The procedure might also be put to use for kidney, liver and heart transplants down the road, said Dr. Gary Levy, head of the hospital's transplant program.
One outside colleague said the highly technical process will have to be simplified before it can be widely used by transplant surgeons, but said the achievement is "hugely important" nonetheless.
"It's very innovative," said Dr. Robert Levy, medical director of lung transplants for B.C. Transplant. "The worldwide transplant community is really watching this with a great deal of interest."
Andy Dykstra, 56, the first patient to receive a reconditioned pair of lungs from the Toronto team, said the operation has made a remarkable difference. Barely two weeks ago, he could not reach his front door without feeling short of breath, and sometimes unexpectedly lost control of bodily functions. He had been diagnosed five years ago with chronic obstructive pulmonary disease (COPD), a condition in which the lung's airways become dangerously narrowed.
Then, two weeks ago, he received lungs whose original, inflamed state would normally have made them useless. The Toronto General team kept them alive in their new system, treated the inflammation and drained excess water, before transplanting them into Mr. Dykstra.
"It's a whole new life," said the retired cabinet maker from London, Ont., who just got out of hospital on Wednesday. "I can breath easier. I'm more full of life. I'm just a changed person."
The world's first, experimental lung transplants were performed at Toronto General in the 1980s, but have quickly became routine. Just in the past decade, the number carried out in Canada has almost doubled to more than 170 a year, according to a report released this week by the Canadian Institute for Health Information.
The problem, though, is that demand far outstrips supply. Lungs can suffer damage in the brain-death process while being ventilated in the intensive-care unit or in car accidents, leaving only 10-15% that can be safely transplanted.
The new technique should be able to all but reverse those figures though, ensuring as many as 50% to 60% are useable, Dr. Keshavjee said.
Lungs and other organs are usually kept chilled after being harvested from a brain-dead donor, an attempt to slow down tissue death. But in such a state, cell metabolism is curbed and repair cannot be carried out.
The Toronto General team developed a system for what is called "perfusion," which keeps the lung alive and healthy for as long as 18 hours. In the meantime, the doctors can diagnose and treat its problems with drugs or, in future, with genetic therapy.
The breakthrough holds other potential, too. It could allow surgeons to adjust the lungs' immunological properties, essentially making them compatible ahead of time with the recipient's immune system.
That could render redundant the long-term use of immuno-suppressant drugs, which are designed to prevent the body from rejecting someone else's organ but which also can lead to serious infection, cancer and kidney damage.
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