Rees phoned his daughter, who called 111 for an ambulance.
"By then I was vomiting, and really feeling crook."
St John decided Rees needed to be taken to Waikato Hospital for urgent surgery.
He would be airlifted by helicopter.
Addressing a crowd at the birthday celebrations, TECT Rescue Helicopter founding pilot and base manager Liam Brettkelly reflected on Rees' rescue.
He said Rees went into cardiac arrest as soon as he was loaded onto the aircraft.
"So we pulled him out, shocked him with a defibrillator, and put him back in an aircraft."
This then happened another three times until Brettkelly told Rees to "start behaving". He went into cardiac arrest a total of four times on the helipad.
"I turned to Dave and I said 'you need to start behaving yourself Dave, so we can get you to Waikato Hospital'. So he did."
TECT Rescue Helicopter founding pilot and base manager Liam Brettkelly. Photo / Salina Galvan Photography
Bretkelly said state of the art medical equipment on the helicopter enabled medics to "do their magic".
The last thing Rees remembers of this time was seeing white, with his surroundings suddenly becoming "very quiet and very peaceful".
"It was almost like a light switch turned off. I remember it very, very clearly. Everything went a brilliant white. And I think at the moment I died.
"These guys obviously shocked and brought me back again. They put me back in the helicopter, then the same thing happened again. That happened four times, but I have no recollection of that," he said.
"The next memory I have is landing on the roof at Waikato."
Rees was released from hospital two days later, unable to have surgery because of the risks associated with the procedure.
However, doctors have told him he could live "pretty happily" even though his heart was only pumping at 35 per cent.
"That was back in August, and I am still here," he said.
"I have made myself really fit, so I want to know if I have improved since then."
Rees, who will celebrate his 80th birthday next week, believed he wouldn't be alive without the help of the helicopter crew.
"It is only thanks to the skill of these guys that I am going to see that birthday," he said.
"I am very grateful to these guys because without them I would not be here. I am a very lucky man."
The helicopter was tasked on its first life-saving flight two decades ago on July 2, rescuing a 2-year-old boy who had fallen into a septic tank, partly filled after a few days of heavy rain.
The toddler squeezed under a fenced-off area and within minutes he was found facedown, unconscious in the water.
Today, callouts to mass casualties, roadside and off-road incidents, marine mayday calls and bush and mountain search and rescue missions mean the crew responds to roughly 40 missions a month. Last year alone, the helicopter completed 448 life-saving missions.
