Up to half of all hospital accident and emergency departments face cuts or closure under plans to improve patient care, presenting Gordon Brown with a massive dilemma as he takes over as Prime Minister.

Ninety-two out of 204 A&E departments are under threat if guidance attributed to the Department of Health by NHS trusts is followed, the Conservatives claimed last night.

Some NHS organisations are already using the guidance, which calls for A&E departments to serve a minimum population of 450,000 patients, to justify closures in smaller catchment areas. The average A&E unit currently serves just under 250,000 people.

But the plans are proving hugely unpopular, even though they have been promoted as in the interests of patients and NHS staff.

Mr Brown, aware that the closures would come into force around the time of the next election, said last Friday that he would meet front-line NHS staff and patients to discuss health policy.

It was clear last night that the Chancellor will not now face a leadership challenge as he prepares to succeed Tony Blair, having gathered a decisive 308th supporter among Labour’s 353 MPs.

Last Sunday Mr Brown accepted that people were worried about the potential closure of A&E facilities and maternity services close to their homes, raising speculation that he was pondering a rethink. If so it is increasingly likely that he will move Patricia Hewitt, the Health Secretary, from her post to pave the way for changes.

The Conservative estimate of 92 nationwide cuts was based on figures in a report circulated to NHS trusts in Surrey.

It states: “Current Department of Health and strategic health authority guidance suggests that, to be viable in terms of patient need, patient safety, staffing numbers and clinical training requirements, a full A&E department in the future would need to be supported by a catchment population of between 450,000 and 500,000 people.”

A staff briefing by Surrey Primary Care Trust in March repeated the figures, suggesting that such a catchment population was “national guidance”.

Closures could mean seriously ill patients, such as those with heart problems or head injuries, having to travel longer distances to receive care in specialist treatment centres. Patients with minor injuries are expected to be treated in walk-in clinics or smaller A&E units.

Such a scenario was supported by two reports published by the Government last year. These suggested that specialist high-tech centres could save 500 lives of people suffering heart attacks and result in 1,000 more stroke victims avoiding death and disability each year.

The changes are broadly supported by doctors’ leaders but are fiercely opposed by patients’ groups and MPs. Cuts to local NHS services have also been opposed by several senior Labour politicians in their own constituencies.

The move to close A&Es comes just as demands on their facilities are rising. The number of attendances at A&E has risen by more than a million in the past three years and the average number of attendances at each is now 67,000.

A report published last year by the Royal College of Surgeons recommended that the minimum catchment population of a fully resourced A&E department should be at least 300,000. But there is debate about whether catchment areas alone should be used to allocate NHS services. Local geography, healthcare needs and staffing levels may have to be taken into account.

A Department of Health spokesman said there was no such official guidance from his department. “It is absolute rubbish to suggest that we are demanding the closure of A&E departments.

“Any decisions about the shape of A&E services are taken locally so that services reflect the needs of the local population. Where local health authorities believe that patients can be better served by changing the way services should be delivered, it is right that they make those changes, and they will consult locally on any proposals.”

But he admitted that the recommendations were taken from a report by the Royal College of Surgeons supported by Sir George Alberti, the former director of emergency care. He recently recommended the closure of an A&E department in North London. The remaining two A&Es serving the area will be left with catchment populations of 450,000 each.

The Tories claimed that this was evidence of central targets to close units based on the number of patients they served.

Andrew Lansley, the Shadow Health Secretary, said: “Access to accident and emergency services is a vital component of the quality of NHS services. The public know that not every A&E department can provide every emergency service. But there is no clinical evidence which would justify shutting down A&E departments simply because they don’t serve a catchment population in excess of 450,000. Yet that is the basis on which the Department of Health is seeking now to justify closures.”

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