There was a 401% increase in the number of people waiting on a bed at Letterkenny University Hospital last month compared to the previous year.
943 admitted patients waited on a bed at the hospital during October, making it the second most overcrowded hospital in the country last month.
In stark contrast, during the same period a decade ago, 47 people were on a trolley at the hospital.
The INMO’s general secretary Phil Ní Sheaghdha says the high trolley figures across the country is a clear sign of a “difficult winter ahead” for the health service.