The chief executive of the region's ambulance service said he was making inroads to improving staff morale after it emerged that 55pc of staff suffered work-related stress last year.

Staff motivation has hit an all-time low at the East of England Ambulance Service, according to the latest national NHS staff survey results. Almost 50pc of those that took part in the 2012 survey said they had witnessed potentially harmful errors or near misses in the last month.

Staff and union officials yesterday said the results highlighted the atmosphere at the NHS trust, which is under scrutiny for failing to meet response targets.

The percentage of East of England Ambulance Service staff that suffered work-related stress in 2012 was more than 10pc higher than the national average for other ambulance trusts. The percentage of staff witnessing potentially harmful errors was also 10pc higher than the national average.

Tony Hughes, GMB organiser for staff at the East of England Ambulance Service, said the trust needed to boost ambulance numbers and recruit more paramedics to relieve stress amongst staff.

'The ambulance service is in total disarray. Lots of investment needs being put in to get it right and policies and procedures are not fit for purpose. Staff morale is almost zero. All efforts should be put in to look after patients rather than wasting time on foundation trust status,' he said.

More than 400 staff at the region's ambulance service took part in the latest NHS survey. The only area where it performs better than other ambulance trusts was the percentage of staff having equality and diversity training in the last six months.

Interim chief executive Andrew Morgan, who has been in the role for three months, said improving service for patients and raising staff morale were his top priorities. He added that he had already made a number of changes including putting an extra 15 ambulances on the road, launching a recruitment drive for more front-line staff, and given more power to local managers by introducing sector leaders across the patch.

'I have been listening to and talking with as many staff as possible since I joined the trust so these results are very sadly not surprising but they are still a cause of great concern. As worrying as these results are I would much rather know what the issues are among staff and am grateful to have even more information to be able to inform the changes we need to make, whether they be trust-wide or at a local level,' he said.

The Department of Health has drafted in Anthony Marsh, the chief executive of the West Midlands Ambulance Service, to conduct an independent review of the East of England Ambulance Service and turnaround its performance, it emerged last week.

A Norfolk paramedic yesterday told the EDP that the ambulance trust should have spotted the signs in previous NHS staff surveys.

'For the last two to three years there has been a steady decline in the staff survey results and it is pretty bad. There is nothing more demoralising than turning up to a job where patients have been waiting ages for an ambulance to show up.'

'I think it will take time and people accept that. However, the management that led us to this position are still in position and until there is a big change, nothing will ever change,' the paramedic said.

A spokesman for the Department of Health said the NHS staff surveys were intended for use by NHS organisations to help them review and improve staff experience so that staff can provide better patient care. The Care Quality Commission will use the results from the survey to monitor ongoing compliance with essential standards of quality and safety, the spokesman added.