Woolwich's Queen Elizabeth Hospital is "not fit for purpose" and its newly-merged health trust with Lewisham "requires improvement", inspectors say.
England's Chief Inspector of Hospitals made the shocking findings in his first reports on the Lewisham and Greenwich NHS Trust - formed last year after the closure of neighbouring South London Healthcare Trust - and its two hospitals.
The report found capacity in Queen Elizabeth's A&E - which now takes more Bexley patients since that borough's emergency department closed and would have taken more Lewisham ones if a planned government downgrade there had gone ahead - was limited with a heavy reliance on agency staff.
This was leading to delays in further investigation taking place and specialist advice being sought following patient admission via A&E.
Queen Elizabeth Hospital was rated as inadequate for its A&E, good for its maternity and family planning services, but requires improvement in its other services.
Lewisham Hospital, meanwhile, was rated as good for its intensive and critical care and children’s care - also threatened with a downgrade by the government's failed plans - but required improvement for all other services inspected.
The report found both hospitals were using different models of acute medical pathway, and neither of these led to efficient patient movement between different services. In some wards, patients told inspectors that they felt there was a lack of staff as it could take up to 30 minutes for call bells to be answered.
And it said that, although recruitment programmes were in place to try and fill vacancies, inspectors observed staff shortages in many areas.
Chief Inspector of Hospitals Professor Sir Mike Richards said: "While we would acknowledge that this is a relatively new trust, we identified issues in both hospitals which we require it to take action to improve.
"The biggest problem here is in the A&E at Queen Elizabeth Hospital, which we have rated as Inadequate. Waiting times there regularly exceed the four hour target, there isn’t enough space for the number of people using the service, and the patient pathway from A&E to the ward doesn’t work as well as it should.
"Most patients we spoke to across both sites praised the caring nature of the staff looking after them, and told us that they were treated with respect and dignity. We saw this for ourselves – although the trust still has some work to do for this feedback to be universally positive.
"We’ve rated this trust as Requires Improvement overall. The trust has told us it will take action – and we’ll return in due course to make sure that it has done so."
A spokesman for Lewisham and Greenwich NHS Trust said: "As a new organisation, formed in October 2013, we welcomed this inspection by the Care Quality Commission (CQC). It complemented quality assessments we had been carrying out ourselves to ensure we have a good understanding of how our services are performing and to identify areas where we need to improve.
"We were pleased to find that there were many positives recognised in the CQC’s report. We will be making sure that we build on what we do well and learn from best practice within the organisation.
"The report focuses in particular on Queen Elizabeth Hospital’s A&E. The trust had already identified a number of these issues, and has been working with partners to reduce patient waits and improve the flow of patients through the department. We are also developing plans to improve the facilities so patients are treated in the right environment.
"While much progress has already been made, we have lots to do and over the next month we will be developing an action plan in response to all the issues highlighted by the CQC. We are pleased to have the full support of our partners and look forward to working with them to deliver significant improvements for local people."