THE future of Southampton children’s heart unit is in fresh doubt as it is poised to be ordered to meet tougher standards – or close.

Health chiefs have drawn up new rules to decide which centres should remain open to settle a bitter, decade-long controversy which, they admit, threatens safety and quality.

In theory, all ten units across England – including at Southampton General Hospital – could survive the shake-up – a change from previous proposals that demanded fewer, bigger units.

However, a fresh battle for survival is likely, with a list of new standards including:

That each unit has at least four heart surgeons, to provide treatment around the clock and cover for staff absences.

That every surgeon carries out at least 125 operations a year, averaged over three years, to ensure they build up expertise in the complex procedures.

In common with most units, Southampton has only three cardiac surgeons, according to official statistics.

And it carried out only 281 operations in total in 2012 – when a minimum of 500 would be required – fewer than at Bristol where 315 took place or the Royal Brompton, in London, which did 351.

Now families, charities, MPs and hospitals in the city must once again make their arguments for saving Southampton’s unit, with an event being held in the city on November 13.

A spokeswoman for NHS England said: “There is a general consensus that four surgeons is the minimum, to provide enough cover when someone is on holiday or called away on urgent business.

“And 125 operations is the minimum each surgeon needs to carry out each year in order to keep their skills up to date and to ensure they are working on the most complex cases.”

The fresh consultation comes 15 months after Health Secretary Jeremy Hunt scrapped plans to concentrate surgery in seven centres – including Southampton – and axe three others.

To the frustration of campaigners in the city, Mr Hunt accepted the conclusions of an independent panel that the closure plan was “based on a flawed analysis”.

The Daily Echo collected more than 250,000 signatures to support the city’s children’s heart unit, as part of our Have a Heart campaign.

However, concerns about babies dying unnecessarily – because doctors carry out too few operations to build up the necessary expertise – date all the way back to 1989.

Southampton General Hospital was unable to comment about the latest consultation when asked by the Daily Echo.

Units will be given three years to beef-up their capacity, if necessary. If they are unable to do so, they could be forced to close, or merge with other centres.

The consultation document is available at http://bit.ly/1BGwilF. The deadline for having your say is December 12.