Thousands of patients could have surgeries cancelled tomorrow as up to 10,000 healthcare workers go on strike.
There is still no sign of a resolution between the HSE and hospital support staff.
Porters, cleaners, chefs and maternity care assistants are among the workers that will stage a 24-hour walk-out tomorrow.
The staff did not get a pay rise recommended in a job evaluation scheme, which has led to this dispute.
38 hospitals and healthcare facilities will be affected by tomorrow's industrial action.
And the HSE has acknowledged it will have a "significant impact" on services despite back-up plans being put in place.
Patients whose appointments could be affected will be contacted by their local healthcare facility.
Both sides could return to talks today to try and resolve the row - but at this point, there is no sign of that happening.