Additional reporting from Vivienne Clarke.
Nurses will consider strike action unless the Government takes action and improves the current "crisis" in Irish hospitals, the Irish Nurses and Midwives Organisation (INMO) said on Wednesday.
The union said 838 patient were waiting for a bed on Wednesday morning, the second-ever highest trolley figure recorded. Tuesday saw the highest, with a record-breaking 913 patients left on trolleys.
Taoiseach Leo Varadkar admitted on Wednesday that the situation is "not acceptable".
"The Government and the HSE are doing everything possible to improve the situation," Mr Varadkar said.
General Secretary of the INMO Phil Ní Sheaghdha said that the union will consider industrial action if the situation does not improve across the board.
"The Government must listen to the frontline workforce," Ms Ní Sheaghdha said. "If they are saying, 'this has escalated to a point where it is beyond unsafe', we're not happy to continuously be asked to go into those situations."
"We're not confident at the moment that the solutions that have been put forward are anything other than, 'wait until the crisis reaches a maximum and then deal with it'."
A statement from the INMO on Wednesday morning slammed the Government, stating nurses were being left to apologise on the State's behalf to patients and families.
"Our members are treating patients in the most undignified conditions. This is not the type of care they should be providing in a country that has the resources to provide additional capacity and support."
On Wednesday morning, it was reported that Minister for Health Stephen Donnelly would meet with Cabinet ministers to update them on the spiralling crisis.
Speaking on RTÉ radio's Morning Ireland on Wednesday, emergency medicine consultant Dr Peadar Gilligan has called for the implementation of the full capacity protocol at all hospitals with emergency departments.
Dr Gilligan, who is based at Beaumont hospital in Dublin, said that implementing the protocol would mean that rather than housing patients in the emergency department who need to be on a ward, those patients would be moved to ward areas “where they may well be in a bed or a trolley awaiting further care, but that is a safer environment.
“It is safer to move one or two patients to a ward rather than treat the emergency department like it has rubber walls."
The situation in Beaumont hospital was “particularly challenging” at present, he said, with 34 patients currently in the Emergency Department who had been assessed and deemed appropriate for admission but there was no hospital bed for them.
“Essentially that means that 100 percent of the capacity of the ED is occupied by patients who are waiting for a hospital bed,” he added.
Dr Gilligan said the solution was to develop capacity: 5,000 acute beds are needed, and they need to be delivered in a timely manner.
When asked if patient lives were at risk because of the current conditions, Dr Gilligan replied: “Definitely.”
Overcrowding in emergency departments meant delays in diagnosing and treating heart attacks and strokes and delivering antibiotics.
“Definitely there are clinical consequences to our failure to develop the capacity that the system clearly needs. Lives are definitely at risk. The reality is we don't have the beds in the system that we need.”
