"There was a totally different feel about it to anything I've ever done. It was tranquil, it was reverent and it was done with a lot of care," she says.

"The first time I was in there, the surgeon said to us, 'This is a very special experience. We treat these people with a lot of dignity'. He set the tone and it was absolutely beautiful."

At the time, Mrs Wilkinson never imagined she would live to surrender her own son to surgeons doing the same procedure. But when tragedy struck last year, she knew exactly how much respect he would be shown.

In a terrible accident, Mrs Wilkinson's 26-year-old son, Wil Taylor, was out jogging along a dark road and listening to music when he was hit by a car from behind.

About 10 days later, he became one of 378 Australians to donate their organs shortly after death in 2014. He was also one of a growing number to have the surgery after his heart stopped.

Until about six years ago, the vast majority of organ donation surgery occurred when somebody was diagnosed as brain dead. This meant they could stay on a ventilator to keep their heart and lungs pumping blood to their organs for the surgery, even though they were legally dead and could not feel anything.

But in recent years, "donation after circulatory death" has soared from 42 cases in 2009 to 107 last year. The new pathway has meant people who suffer fatal illness but who are not brain dead can still become donors when their heart stops.

Mrs Wilkinson knew Wil, who was as pragmatic as he was generous, would want to be an organ donor. On the night before his breathing machine was turned off, she said the nursing team caring for Wil at the Alfred Hospital set up a bed for her so she could lie next to him and hold him.

"It was probably one of the most restful sleeps I had had since the whole ordeal happened. It was raining and had been dark the whole week that Wil had been in hospital, but on that next morning, the sun came out ... It was just streaming in. I thought, 'Wow, what a day for these people to get a call to say they are going to receive these organs'."

That morning, hospital staff gently let Wil go. Knowing that time was limited for surgeons to take his organs, Mrs Wilkinson insisted they take her son quickly.

"The nurses were all saying goodbye and I said, 'Just get him down to theatre'," she says of the moment.

"I went to the chapel afterwards and sat there and thought how is this part of the plan for Wil? … I thought this isn't really about Wil, this is about all the people he has helped. He is part of their lives, he is interwoven into their lives so that they can continue."

Four people benefited from Wil's donation. One received his lungs, one received his liver and two people got a kidney each. All of them have children and two of them have written to Mrs Wilkinson to express their profound gratitude.

To find out more and to register to be an organ and tissue donor, visit donatelife.gov.au/decide