The Irish Nurses and Midwives Organisation says today's trolley figures represent a worrying spike in hospital overcrowding.
663 people were waiting at hospitals across the country today.
There were 55 in total waiting at the two main North West hospital this morning, 21 in Sligo University Hospital and a further 34 in Letterkenny.
In a statement, INMO says its members are once again expressing serious concerns about their ability to provide safe care to all who need it in hospitals.