Nurses who have been working in "constant crisis" for years led the demolition of Oxford's old casualty unit to celebrate the construction of a new critical care centre.

Accident and emergency staff were joined by a past patient yesterday as they swapped stethoscopes for mallets to smash a wall at the John Radcliffe Hospital.

It signalled the start of a £20.3m development scheme, including a new casualty department with a dedicated children's area, critical care research centre, trauma unit, and intensive care and high dependency unit.

Sister Annette Hack and former patient Nick Mainwaring

Casualty sister Annie Nelhams said: "We are going to have just as many patients at the new centre, but we will be able to find new ways to maintain their care.

"We have been working at crisis point for the last few years.

"The nurses have been a strong force in trying to solve the problems and at one point we threatened industrial action because we were at the end of our tether."

Neil Ashley, chairman of the Oxford Radcliffe Hospitals NHS Trust, which is responsible for the JR, admitted that the casualty department had seen "second class conditions for too long".

Patients were often forced to wait on trolleys in corridors while queuing for beds in medical and surgical wards in the Headington-based hospital. Mr Ashley said: "There has been some real and increasing pressures on our front door A&E department. This has surely got to be the beginning of the end."

Joining hospital staff at the demolition was former meningitis victim Nick Mainwaring, 18, of Sunningwell, near Radley, who was admitted to the JR earlier this year.

In February, Mr Mainwaring arrived at casualty where his condition was confirmed and he was admitted to intensive care.

He missed six weeks of A-level studies at d'Overbroek's College, but recovered to take his exams. He is now waiting to read international relations and French at Sussex University.

Mr Mainwaring said: "This new development will be brilliant. The casualty staff are wonderful and friendly and if this new building makes a difference, then that's important."

Fiona Dalton, head of A&E, and trauma, said: "The trust feels that the combination of these various redevelopment projects and other initiatives will focus energy and resources into a modern, responsive and dynamic emergency and trauma service for Oxfordshire."

The new casualty department is expected to open in February 2003, while the whole development should be ready for use by the end of that year.