There are 76 patients on trolleys in University Hospital Limerick waiting admission to a hospital bed, according to the Irish Nurses and Midwives Organisation.
Overall, 515 patients are on trolleys in emergency departments or wards waiting for beds in hospitals around the country.
Other hospitals badly affected include Cork University Hospital with 49 patients on trolleys, 34 at University Hospital Galway and 28 at Tallaght University Hospital.
The INMO says 369 patients are in emergency departments and 146 are on wards.
