A strike by non-consultant hospital doctors is to go ahead tomorrow after the failure of last-minute talks between the Irish Medical Organisation and the HSE to avert it.
Hospitals have cancelled outpatient appointments and elective surgery planned for tomorrow.
The strike is expected to affect up to 15,000 patients.
HSE management instructed senior staff on Friday to reactivate previously prepared contingency arrangements for the strike.
The Labour Relations Commission made informal contact with the parties last Friday see if doctors were prepared to return to the negotiating table but the IMO repeated its view that there was no point in this because of the breakdown in trust with the HSE.
HSE director of acute hospitals Ian Carter then wrote to the heads of hospital groups telling them to communicate directly with patients whose appointments on Tuesday will be affected. Mr Carter said patients should be given a new date for their appointment where possible.
Hospital managers have also been told to contact local union representatives in order to ascertain which services will continue to be provided as normal.
The IMO has said members will provide the equivalent of a Sunday service on Tuesday but that emergency, oncology and dialysis services would not be affected.
IMO assistant director of industrial relations Eric Young said the time had come for action because the HSE had failed to provide a detailed and satisfactory response to its proposals on the issue of long working hours for NCHDs.
While the Minister for Health James Reilly and the HSE said little separated the sides, Mr Young insisted there was “quite a difference” between the IMO and the HSE.
The key issue relates to the imposition of sanctions in cases where hospitals fail to limit shifts to a maximum of 24 hours.