The Chair of the South SouthWest Hospital Group has resigned from her post, saying progress on reform has stalled for years.
Professor Geraldine McCarthy's listed a number of changes that were promised but not delivered, including free GP services and addressing waiting lists.
It comes less than a week after two senior officials in the Slaintecare programme also resigned.
The South/SouthWest Hospital Group oversees 10 hospitals, including Cork University Hospital and the maternity hospital, Mercy University Hospital, Waterford, Kerry and Tipperary University Hospitals
Sinn Fein Health Spokesman David Cullinane says the Minister needs to appear before the Health committee to explain this, and a list of other issues.
"He has to explain what's happening. He needs to explain what's happening within the HSE and the Department of Health.
"He quite clearly has to come before the Health Committee as a matter of urgency, because we have spiralling waiting lists, we have over 900,000 people on some form of health waiting list, we have 200,000 people waiting on some form of diagnosis."