Al Finke is just one of 12 people involved in a complex kidney swap that spanned three cities and saved the lives of six people nationwide.

"Over powering. I feel like it's God's hands. He took care of me," Finke said.

The swap was spearheaded at The Johns Hopkins Hospital.

"It's logistically very complicated," said The Johns Hopkins Hospital transplant surgeon Dr. Andrew Singer. "This is the first large, inter-institution exchange we've done."

It starts with one person, the altruistic donor, who wants to donate out of pure good will. That kidney is matched with a recipient who has a living donor, but isn't a match. From there, doctors find other mismatched pairs who can be compatible.

"By swaps or exchanges, two incompatible pairs potentially can be transplanted by virtue of that and by including even other people," Singer said.

If one person drops out, then the whole chain can fall apart, he said. But since Hopkins doctors were working with hospitals in St. Louis and Oklahoma City, they had a wider pool of people to work with.

"I've been blessed with the most amazing health," said Cindy Dabrowski. "It is God's gift when you are so healthy."

Dabrowski is the altruistic donor. She said she decided to give one of her kidneys because she wanted to share her good health with others. Her kidney turned out to be a match for 32-year-old Shelby Fletcher.

"So many people were involved and so many people got their lives changed in one day," he said.

At the end of the chain was 70-year-old Finke. He was on dialysis for nearly four years before Sharon Solof got involved in the swap. She donated because she wasn't a match for her own husband, who needed a kidney.

"I had trouble accepting it and I still have trouble accepting it," Finke said. "It's such an overwhelming thing."

This was one of the largest, inter-hospital kidney swaps ever done. Doctors say they hope to use this as a model for future organ donations.