It started as just another day on the job for Brisbane factory worker Lawrence "Lorry" Cooper.

But in a spilt second, while operating a meat slicer, the 23-year-old's life changed dramatically when his hand was severed below his thumb.

"I only remember glimpses after I did it," Mr Cooper said.

"It's pretty terrifying when you see your hand missing, just a lot of different emotions."

Warning: Graphic images of a medical procedure below

"Most of it wasn't actually pain, a lot of it, they call it phantom pain where you can still feel your pain even though it's not there," he said.

A quick-thinking colleague grabbed the severed hand, preserving it in ice, and applied a tourniquet to his arm.

Mr Cooper was then raced to the Mater Private Hospital where plastic and reconstructive surgeons had established two teams to give him the best chance of having his hand reattached.

"Before we could even consider reattachment we had to establish if we could reconnect the blood supply to the severed hand within a viable timeframe," surgeon Theo Birch said.

He said they were helped by the fact Mr Cooper's amputation was clean and sharp. There were no jagged bones, making reattachment a bit easier.

Dr Birch and colleague Andrew Hadj worked to clean and prepare the site.

For the next seven hours the pair performed meticulous microsurgery on Mr Cooper's hand — starting from the inside out.

The surgery lasted seven hours. ( Supplied: Mater Hospital )

Stabilising the bone was the first job — the pair constantly talking to each other about which blood vessels were viable.

"Unfortunately you can't just connect an artery together straight away to restore blood flow as the construct is too flimsy," Dr Birch said.

"You need to plate and screw the bones together, repair the deeper tendons — only then is it safe to focus on the fine microvascular surgery."

While the pair have had to reattach the odd finger or two, reattaching an entire hand is rare. Because of that, Mr Cooper was carefully monitored in intensive care for several hours after the operation.

Surgeons say reattaching a whole hand is rare. ( Supplied: Mater Hospital )

"If any of those blood vessels get a small clot or thrombus in it, then the whole circulation goes off," Dr Birch said.

The following day Lorry Cooper was moving his fingers, which doctors describe as miraculous. They're confident his prognosis is good.

"His movement the next day was promising," Dr Birch said.

"We gave him a day's rest, put it into a splint and got things moving to improve the chances of success.

Doctor's are still monitoring Lorry's progress. ( ABC News: Leonie Mellor )

"Cut nerves are the most unpredictable part of the process because for a successful recovering they need to grow, which is a very slow process."

Mr Cooper had the surgery in late August and while he knows the road to recovery is long, he's hopeful of regaining full use of his hand.

"You're always grateful and you're always happy but there's a lot of mental issues," he said.

"I think you've just got to be strong-willed … it's just about seeing how it progresses."