The Irish Nurses' and Midwives' Organisation has criticised the Health Service Executive for not being prepared for the rising number of flu cases.
The INMO have said the HSE were not prepared for the level of overcrowding in hospitals resulting from large number of flu cases.
It has said the high trolley figures over the festive period were entirely predictable, but there has been no plan to stem the worst of it.
Nurses are calling for a national emergency plan to be implemented with 761 patients waiting for a bed today.
Impacting patients and staff
General Secretary of the INMO Phil Ní Sheaghdha said the lack of action is impacting patients and staff.
"Clearly you cannot continue to turn up to try and do a decent and a good day's work when your employer is simply not providing you with the tools to do it," she said.
"We're looking at figures from last Thursday, January 2nd - 571 people on trolleys - and today that has increased up to 761."
The INMO has said that the HSE and other public sector healthcare employers must reassure healthcare workers and the wider public that "extraordinary measures" are being taken to address and remove all barriers to delivering safe care during this "critical time".
Ambulances outside Beaumont Hospital in Dublin. Image: Alamy