The Irish Nurses and Midwives Organisation has said that the situation at Beaumont Hospital's emergency department remains chaotic.
Despite calls from the INMO for the emergency department to be closed to new arrivals due to overcrowding, it remains open.
27 patients were admitted this afternoon.
The hospital, one of the busiest in the country, was forced to seek assistance last night from Our Lady of Lourdes Hospital in Drogheda, due to the scale of overcrowding in its emergency department.
The hospital said it had been "provided with off-call assistance" by Drogheda to relieve pressure.
It said it regretted the difficult conditions experienced by patients and staff.
A spokesperson said Beaumont had not officially gone off-call.
The INMO at the time had said the emergency department was severely overcrowded with 41 patients awaiting an in-patient bed.
It asked that Beaumont Hospital go off call immediately for an extended period.
Nurses said patients have been forced to spend days on trolleys and chairs in frantic, bright and noisy conditions, waiting for a bed to become available.
INMO Industrial Relations Officer Lorraine Monaghan said it was unacceptable that patients were being subjected to such degrading, inhumane conditions when they are at their most vulnerable.
Beaumont said that 33 in-patient ward beds are not available, due in part to essential refurbishment work for transplant patients.
The work is due to be completed by the end of next month.
