There are 66 patients on trolleys or on wards awaiting admission to a bed at University Hospital Limerick, one of the highest levels ever seen at a single hospital.
There are 37 patients in the emergency department and 29 on wards, according to the figures from the Irish Nurses and Midwives’ Organisation.
The overcrowding figure from Limerick compares with 58 patients on trolleys or on wards at Our Lady of Lourdes Hospital in Drogheda in October 2011.
In a statement, University Hospital Limerick said it has one of the busiest emergency departments in the country, seeing over 60,000 attendances a year.
The hospital said it regretted that any patient had to face long waits during busy periods.
It said extra medical and nursing staff have been recruited to deal with increased pressures.
The University of Limerick Hospitals Group said that a new emergency department, triple the size of the existing one, is being fitted out and is due to open next May.
There are 456 patients on trolleys or on wards in hospitals around the country.
Other hospitals badly affected by include University Hospital Galway with 43 patients waiting; Our Lady of Lourdes in Drogheda with 36 and South Tipperary General with 34.
Health officials at University Hospital Galway have apologised to patients and their families for delays at the emergency department today.
The Saolta University Health Care Group said the department remains extremely busy and the Full Capacity Protocol has been implemented.
It said all efforts continue to be made to identify patients who are appropriate for discharge.
Management at the hospital are advising patients that that they can expect delays and are encouraging people to only attend in the case of real emergencies, otherwise they should contact their GP, or GP Out-of-Hours service first.
In early September, Minister for Health Simon Harris and the Heath Service Executive announced a new winter initiative.
Under the plan, from 1 December overcrowding cannot exceed 236 patients on any single day.
The plan was due to come into effect during October and November.
It provided for 55 extra acute beds, at five hospitals which were experiencing severe overcrowding.
They were identified as: the Midland Regional Hospital in Tullamore, Beaumont Hospital, Naas General Hospital, University Hospital Waterford and in the Midland Regional Hospital in Mullingar.
In addition, 18 step-down beds were to be provided at the Mercy University Hospital Cork.
At those hospitals targeted under the plan, overcrowding levels today are relatively low, except for Mullingar and Cork.
Meanwhile, the Irish Nurses & Midwives Organisation has announced it is to ballot its 40,000 members in pursuit of special recruitment and retention measures to address the current staffing crisis.