A city health worker is racing against time to raise cash to bring her critically-ill father back from Thailand, where his hospital bills are £3,000 a day.

Raymond Wallace, a 72-year-old retired lorry driver, set out to travel around Asia and Thailand three years ago after his partner died of a brain tumour.

The dad-of-six was in the city of Hua Hin last week when he suddenly started having serious respiratory problems.

His family thought it was a scam when they received a call at 5am from a Thai hospital saying Raymond was “fighting for his life” and money was needed to pay for his treatment.

Raymond Wallace was travelling around Thailand when he became critically ill

placeholder image — Raymond Wallace was travelling around Thailand when he became critically ill

But sadly it proved to be correct, said his daughter Karrie Wallace. "Our worst nightmare has come true...” she told MailOnline today.

The hospital has described Raymond’s condition as a “mystery illness” and have sedated him and put him on a ventilator why doctors try to discover the cause.

Karrie and her brother are flying out to Thailand this week to see him, but meanwhile they have discovered his travel insurance had unexpectedly expired just before he was taken ill.

Now they’ve been told his medical bills are exceeding £3,000 a day – and will be even more if he needs to be transferred to a specialist hospital in Bangkok.

The family is still struggling to find out exactly what is wrong with the previously fit and healthy pensioner. At first doctors thought he pneumonia, but later changed their diagnosis to acute respiratory distress syndrome.

But when the family called the British embassy in Thailand, they were told that he may have kidney problems, said Karrie.

She told MailOnline: “[The doctors] keep saying to us: "Oh we’re just going to keep him sedated for a couple of days to see if his vital signs improve. If they improve, we’re gonna try to wean him off the ventilator’."

“Or if he doesn't improve over those couple of days, they're going to transfer him to Bangkok Hospital and put him on a different type of ventilator. We haven’t even been given a proper picture in terms of when they’re thinking of doing it.

“At the moment, they’re saying he’s critically stable, and there’s been no change over the last 48 hours.”

In desperation, Karrie, who works in health care, has launched a £45,000 GoFundMe appeal to cover the medical costs. You can view the page here.

It states: “Our dad, a kind and cherished man, has unexpectedly fallen critically ill while in Bangkok. He is currently in the ICU, on a ventilator, heavily sedated, fighting for his life.

"We never imagined we would be in this heartbreaking position, fighting to ensure he receives the treatment he desperately needs. The medical costs are mounting rapidly, and we are doing everything we can to support him and bring him home.

“Our dad is loved by so many, and his children have dedicated their lives to serving others—some in the Armed Forces, others in the NHS. Now, we find ourselves in desperate need of support.

“We are asking for your kindness, your prayers, and, if possible, your financial help. Every donation, big or small, will go directly towards his hospital expenses and the cost of bringing him home to recover with his family by his side.”