Talks will resume on Thursday in an attempt to prevent another three days of strikes by health workers next week.
Some 10,000 staff - including chefs, porters cleaners - will complete 24 hours of industrial action at 8.00am.
The action is affecting 38 hospitals and healthcare facilities around the country.
They are involved in a dispute with the Health Service Executive (HSE) over a job-evaluation scheme and pay.
Both sides return to the Workplace Relations Commission (WRC) later.
Spirits are high on the @siptuhealth picket line at the Louth County Hospital in Dundalk #PayUpNowPaschal #UpTheWorkers pic.twitter.com/3CwKi3YKyH
— Ged Nash TD (@geraldnash) June 26, 2019
However, a spokesperson for SIPTU said that, at this stage, three further strike days planned for next week are expected to go ahead.
More strikes are planned for Tuesday, Wednesday and Thursday of next week if there is no resolution.
On Wednesday, the HSE said it was aware of "in excess of 2,000 cancellations" - including surgical procedures, scope procedures and outpatient appointments.
"Hospitals are facing challenges in maintaining essential daily care for our inpatients such as nutrition, hydration, transfer of patients, cleaning and infection control", it said.
However it added that the services impacted varied across different hospitals, and patients had been contacted by their local hospital or healthcare facility if their scheduled procedure or service was affected.