Epsom and St Helier trust will have a new senior management team and a range of national and regional interventions in a bid to turn around its performance following a damning Commission for Health Improvement report.

CHI found high mortality rates, lack of awareness of clinical guidelines, poor cleanliness, demoralised and overworked staff and soaring costs of complaints and clinical negligence cases.

But the trust's management was singled out for particular criticism: the report said it was defensive and distant, did not value or support staff, and had 'a lack of commitment to developing and progressing towards excellence'. Departing chief executive Nigel Sewell will be replaced on 10 September by John de Braux, currently chief executive at West Middlesex University Hospital trust.

Trust chair Jennifer Denning said Mr de Braux would lead a review of the trust's entire clinical services strategy, including how and where services should be provided, as well as taking forward implementation of a robust action plan following the CHI review. That work could mean consideration of a rebuild at the St Helier site - a scheme first proposed in the mid-1970s - as early as Christmas.

'We have already started the process, but we have a lot of work to do in order to understand much more clearly what we need, and we will then take a decision about a rebuild. In the meantime We have got to make do as well as we can, 'Ms Denning told HSJ.

A new medical director, Dr Lindy Steven, has taken up post, as has a new head of clinical risk management, Rowan Munnerley. A director of clinical operations, Mary Wells, will start next month.

Ms Denning said the trust expects to work closely with teams from the Modernisation Agency and the regional office as well as the local public health department to ensure rapid changes in what has clearly been identified as a failing trust.

'I think the huge strength of the NHS is when you can see the system working together like this. We have got to prove that we have the guts and determination to face up to the fact that we have huge problems and we know there is a lot of help out there to overcome them, ' Ms Denning said.

She acknowledged that the CHI report would inevitably give rise to even greater morale problems among staff but echoed the views of other managers facing CHI criticism: 'It may seem odd, but this report has been very helpful - to see everything together in one document like that gives us an opportunity to turn this whole thing into a success story.'

For the past year the trust has been subject to support and intervention from London regional office, the Winter and Emergency Services Team and the National Patients' Access Team because of its poor performance.

Director of London Health Emergency Geoff Martin said the CHI report was 'the final straw'.

'People at senior level have known the trust can't provide high-quality care for at least two decades. It is the worst in London, possibly the whole of the UK. No other trust is in a plight like it with its combination of problems. It is difficult to imagine a more poisonous cocktail of circumstances. It will require change of seismic proportions to turn things around.'