Irish patients are facing significant appointment cancellations as HSE support staff's planned strike is due to go ahead.
It's understood around 10,000 workers will take industrial action on Thursday.
The strike, planned by SIPTU, will take place across 38 hospitals and healthcare facilities across Ireland.
In a statement on Wednesday afternoon, the HSE said its trying to ensure minimum disruption to services.
But the health chiefs confirmed there will be significant cancellations and deferrals.
It said: "The HSE is continuing to engage on contingency planning with SIPTU at local hospital and healthcare facility level.
"This is to ensure minimum disruption to patient services, in so far as possible, and to ensure patient dignity and that essential daily care remains in place.
"Initial feedback from our hospitals this morning shows the services mostly impacted will include;
- Deferral of some elective inpatient procedures
- Significant cancellation of scope procedures
- Reduced outpatient services
- Reduced laboratory services for GPs
- Reduced catering services for both patients and staff
- Reduced operating theatre activity.
"The services impacted will vary across the hospital sites.
"Patients are being contacted by their local hospital or healthcare facility in the event that their scheduled procedure or service will be affected by the dispute.
"While every effort will be made to minimise impact on patients, industrial action involving these essential staff will have a significant impact on services."
