Heather Makris's life changed forever when she had organ failure during a routine operation in 2016.

The 46-year-old was in intensive care, suddenly in desperate need of a liver replacement.

"I would not make it for very much longer," she said.

While on the organ waitlist, her family prepared their goodbyes.

But on December 27, 2019, she received a phone call notifying her of a liver match.

"That phone call came out of nowhere," said Ms Makris.

Now on National DonateLife Week, Ms Makris is urging for more people to consent to be a donor.

A total of 119 people on the organ recipient waitlist received life-saving surgery last year.

But demand has never been higher with 1,750 seriously ill Australians on the waitlist nationally and another 13,000 people on dialysis who may benefit from a kidney transplant.

"It takes one minute to register and we could catapult Australia in the years to come," Ms Makris said.

"My ultimate dream would be for every sporting group to come onboard during the life of DonateLife Week."

South Australia currently leads the nation with 73 per cent of the state's population signing up to being a donor.

Despite this, DonateLife SA medical director Stewart Moodie says 30 per cent of organs are still not donated in SA, and 40 per cent nationally.

"People do die because they don't get access to a transplant in time," the Royal Adelaide Hospital intensive care specialist said.

"It's an important message for the community to understand.

Regional areas are top of the list of organ donors, with Robe being the highest rate of registration at 89 per cent and Roxby Downs closely following with 87 per cent.

On Sunday, hundreds of South Australians walked or ran in the inaugural DonateLife race to raise awareness of organ and tissue donation. 

"I think it comes down to that sense of community," Dr Moodie said.

"My experience is that they want to look after each other.

"That's the message we need to send nationally."