The Irish Nurses Organisation says the emergency department in Dublin's Beaumont Hospital is severely overcrowded this evening.
The INMO claims there are 41 patients waiting for a bed and the total is set to spiral throughout the night.
The group wants Beaumont to go off call immediately to bring the situation back under control.
18 of those waiting on trolleys are over the age of 75.
The department is also short two nurses and nurses are warning it is impossible to provide a safe level of care to patients in these conditions.
Speaking this evening, INMO Industrial Relations Officer, Lorraine Monaghan said, “It is unacceptable that in 2015 patients are subjected to such degrading, inhumane conditions when they are at their most vulnerable.
"This situation has continued to worsen with overcrowding levels up by 40% in the first 9 months of 2015 compared to the same period last year.”