University Hospital of Wales nurses fears over staffing
BBC Wales health correspondent Hywel Griffith said no NHS board in Wales was currently meeting A&E targets
The Royal College of Nursing (RCN) says concerns are being raised over staffing levels at Cardiff's University Hospital of Wales.
Staff at the hospital have contacted BBC Wales with worries over the pressure placed on them and medical services.
They have also raised issues about lack of capacity to treat patients.
The hospital says it is facing "significant pressure" at the moment, and is working to resolve the issue.
It is understood that a 'breaking point' was reached on Thursday night after it was claimed that patients were being treated in corridors and staff were told to work through breaks.
Tina Donnelly, the director of RCN Wales said: "It's vitally important that staff voices are heard by management, and there is no cut backs in the numbers of nursing staff that are required to deliver safe patient care.
"Our primary focuses are ensuring that patients are not put at risk.
"If staff are saying that they haven't got sufficient staff to care for their patients, then that is obviously why they have gone to the media."
The RCN says it is to hold an urgent meeting with hospital managers to discuss the pressures, and the arrangements for recruiting agency staff.
Jan Williams, chief executive at Cardiff and the Vale University Health Board said: ""The University Hospital of Wales is facing significant pressures at the moment, with the numbers of patients attending the accident and emergency unit and being admitted to the medical wards.
"The nurse director is personally reviewing the staffing requirements, to make sure that the hospital has sufficient staffing to meet the pressures.
"We place the utmost priority on patient safety and care and are working with staff to resolve the issues raised as a matter of urgency."
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