A 14-year-old boy collapsed and stopped breathing while out on a bike ride.
Keen mountain biker Oscar, from Bodmin, was riding at Minions on Bodmin Moor in Cornwall when his heart stopped.
He was rushed to hospital and now remains at Bristol's Children's Hospital where he is awaiting open heart surgery.
His family have spoken of the horrifying moment they received the "second worst call imaginable" after Oscar collapsed.
Luckily for Oscar and his family, a quick-thinking member of the public found a defibrillator to save Oscar's life after he stopped breathing.
Oscar's aunt Gemma Dawe said: "Oscar is 14 years old and mad about mountain biking.
"On Monday last week, we received a call that no one ever wants to hear. Oscar, who is usually completely fit and healthy, had been out on his usual Monday night bike ride and had collapsed and stopped breathing, his heart had also stopped.
“Due to the quick thinking of one incredible person there that night and a team effort of everyone else involved, they managed to perform CPR and get a defibrillator from the nearest village, which resulted in them saving Oscar's life.
“They managed to get Oscar's heart started again and he was rushed to Derriford Hospital, but he had not regained consciousness.
"When he got there, he was still in a critical condition and was transported to Bristol's Children's Hospital, where he was put in an induced coma and put onto life support.
“He remained in a coma for a few days but the team of amazing doctors and nurses slowly brought him out of his coma.
"We were worried sick whether Oscar would come off of life support ok, or whether he would be showing any signs of brain damage from the cardiac arrest.
“Thankfully, Oscar has come back fighting fit and is starting to recover with no signs of damage.”
The 14-year-old is now awaiting open heart surgery for an underlying heart condition he was not aware he had.
Thankfully, Oscar is expected to make a full recovery.
Gemma added: "It was absolutely terrifying – just horrific. It was the second worst call that a family could get. It wasn’t a fun night.
“One little machine, in the middle of nowhere, in a muddy car park on the moors, managed to save Oscar's life.
"We are so grateful to everyone involved in Oscar's treatment, but especially grateful that there was a defibrillator so close to where they were riding.
“Oscar would not be alive now if it wasn't for that defibrillator, so we want to get more into the local community.
"Cornwall has so many rural areas that ambulances would struggle to get to in enough time to save someone's life, so it is vital that these machines are around. So we are fundraising for more.”
Oscar's family, including Gemma, are organising a variety of fundraising events to buy more defibrillators.
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