Over 10,515 patients were treated on trolleys, chairs or in another inappropriate bed space in October according to the Irish Nurses and Midwives Organisation.
Both Galway and Sligo University Hospitals were among the top five most overcrowded hospitals nationally.
University Hospital Galway , with 989 patients treated on trolleys last month, was the third most overcrowded, with Sligo University Hospital the fifth most overcrowded with 663 patients treated on trolleys.
406 patients were treated on trolleys at Mayo University Hospital in October, and that figure is significantly higher than the same month last year, when 356 patients failed to secure a bed.
INMO General Secretary Phil Ní Sheaghdha says this is a grim indicator for the level of overcrowding that is bound to be seen over the winter period.
“Staffing is an issue across all hospitals. Not having a safe number of nursing staff in our emergency departments, inpatient wards, long term care and community services continues to exacerbate the persistent problem of overcrowding in our hospitals.
"The HSE and Government must protect frontline services by lifting the recruitment embargo immediately and accelerating the hiring process, which has been hindered by the current pay and numbers strategy”.
