Bonnie Tyler had to be 'resuscitated after going into cardiac arrest' when doctors tried to bring her out of an induced coma at an Algarve hospital.

The medical emergency led to the worsening of the singer's health condition late last week following life-saving surgery for a burst appendix, respected Portuguese daily Correio da Manha has reported.

The Welsh singer, 74, will remain in the induced coma in an intensive care unit at Faro Hospital until medics manage to control the 'serious infection' she is suffering caused by a perforated intestine, the paper said.

Her long-term friend Liberto Mealha said overnight doctors are 'positive' she can make a full recovery despite the ongoing uncertainty about how things will evolve.

More details have emerged of Bonnie's health woes, which are said to have led to her emergency bowel surgery and the removal of her appendix.

Mr Mealha, who first met The Total Eclipse of the Heart singer when he opened a well-known Albufeira nightclub in the Eighties near the artist's holiday home, said last week: 'She started feeling unwell during a concert in London and went to a doctor for tests, but they didn't detect anything there.

'She decided to travel to the Algarve, where she began to feel severe abdominal pain.

'Two days later, she went to a private hospital, which urgently transferred her to the hospital in Faro because her appendix had burst and she needed emergency surgery.'

Overnight it was reported Ms Tyler, believed to have first started feeling unwell around a month ago, had been bedridden for two days at her Algarve home before her worried husband Robert Sullivan took her to the private hospital she was seen at before being transferred to Faro.

A spokesman for the singer said late last Thursday she had been put in the coma to 'aid her recovery' after reports she had suffered a burst appendix.

A day earlier, when her health woes first emerged, the spokesman had said: 'We are very sorry to announce that Bonnie has been admitted to hospital in Faro, Portugal, where she has a home, for emergency intestinal surgery.

'The surgery went well and she is now recuperating.

'We know that all of her family, friends and fans will be concerned about this news and will be wishing her well for a full and swift recovery.'

Ms Tyler, who has had multiple  hits in her long career and competed at the Eurovision Song Contest representing the UK in 2013, is believed to have been rushed to hospital on April 30.

She was said to have been 'stable' in an intermediate care unit at Faro Hospital before an apparent worsening of her health led to her being transferred to intensive care.

Sources say she had been maintaining her professional activity in the run-up to being taken to hospital, despite complaining of persistent pain for several weeks.

Her representatives have not yet commented on reports she had to be resuscitated.

Cardiac arrest is a medical emergency in which the heart suddenly and unexpectedly stops pumping blood, causing it to stop beating and disrupting oxygen flow to the body and brain.

It causes instant unconsciousness and collapse. Immediate action involving starting CPR and using a defibrillator where available is essential to prevent death.

A ruptured appendix is a severe medical emergency requiring immediate surgical intervention and antibiotics to prevent fatal infections.

When an infected appendix ruptures, it creates a hole and causes fecal matter and bacteria to leak into the abdominal cavity.

Mr Mealha, whose daughter is Bonnie's goddaughter, said last week the singer's husband was spending his days by her hospital bedside and only leaving to sleep at home at nighttime.

He added: 'He's very grateful to the doctors and nurses at the Faro hospital and believes that if Bonnie had stayed in the United Kingdom she would no longer be here.'

Wellwishers have offered their support on social media.

Sara Hadfield wrote: 'My husband spent 10 days eight years ago in an induced coma in ICU in Faro Hospital.

'They cared for him very well. I hope they do the same for Bonnie.'

Jenny Edwards added: 'Come on Bonnie girl. Us Welshies don't give up. Here is to a full recovery.'

And Portuguese national Maria Joao Raposo Fonseca said: 'Speedy recovery for Bonnie.

'She is such a lovely lady. I lived close to her in Albufeira and used to see her all the time at my hairdresser's salon doing her tanning and then driving her little red convertible.'