Dr. Atul Humar, director of the multi-organ transplant program at University Health Network, told a news conference Thursday that the 55-year-old Melnyk remains in the intensive care unit but had been awake, smiling and answering questions earlier in the morning.
"Both the recipient and the donor are currently stable and recovering well from their operations," said Humar.
The hospital would not identify the donor, nor reveal their age or whether the individual is male or female. Doctors said the donor wished to remain anonymous to both the public and to Melnyk.
"However, the donor has asked me to tell you the motivation to do this is to help Mr. Melnyk return to good health, to enjoy his family and friends — and most importantly, to bring the Stanley Cup home to the Ottawa Senators," said Dr. David Grant, who led the surgical transplant team.
More than 500 people offered to be a living liver donor for the billionaire NHL team owner following a public appeal last week by the Ottawa Senators organization.
Melnyk, who was suffering end-stage liver failure due to an undisclosed disease of the organ, was in urgent need of a transplant, his doctors said.
Though they would release limited details about Melnyk's case, a liver transplant operation typically takes six to eight hours and recipients typically stay in hospital for up to two weeks, then take three to six months to recover fully.
In a statement read by spokesman Ken Villazor, Melnyk's family said that in the 36 hours after the transplant, they had "already witnessed a dramatic improvement in Eugene's overall condition."
His family thanked the transplant team and the donor, saying "you are an incredible person and we truly admire your unselfish act of kindness and courage."
"You remain in our thoughts and prayers and we wish you a speedy and full recovery."
Melnyk had been on the waiting list for a deceased donor organ for several weeks, but having a rare AB blood type meant that finding a living liver donor was really his only option. None of his family or friends were deemed to be medically suitable donors.
A severe shortage of deceased donor organs means one in three people on the transplant waiting list in Ontario die because a heart, liver, kidney or other organs don't become available in time, said Grant. There are currently about 1,500 people on that list.
Besides raising awareness about the desperate need for organs, the public appeal for Melnyk had a broader beneficial effect, said Grant.
"It's an amazing gift because it not only saves the life of the person who receives this organ, it also frees up an organ ... for someone else (on the waiting list) who may not have this option," he said.
As well, about 20 of the 500 people who volunteered to be living donors for the Senators chief have said they are willing to donate to other people in need of a new liver.
"So many lives will be saved as a result of this appeal, and we as a community should be very proud of these heroic, caring individuals," Grant said.
Dr. Ian McGillvray, who headed up the donor's surgery, said about 70 per cent of the person's liver is removed, along with some blood vessels and bile duct for the transplant.
Donors, who are at risk of infection, bleeding and blood clots, stay in hospital from five to nine days, then are off work for two to three months while they recover from the painful surgery; their liver grows back in about six weeks.
"I can't think of anything else in modern medicine where you take a completely healthy, well individual and then subject them to an operation of this scale and they get nothing out of it except the fact that they've done something good for somebody else," said McGillvray.
Working with these donors, he said, "is truly humbling."
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