A $1 billion digital system to store patient medical records went live in the Hunter on Wednesday, amid concerns about the effects on staff and patients.
The system will store people's medical records in one place, including electronic referrals, test results, appointments and treatment history.
It is expected to bring an end to the use of fax machines for patient records and the printing of clinical notes within hospitals.
The system will mean patients don't have to keep repeating their story, including treatment, medication and health history at every visit.
Tracey McCosker, Hunter New England Health's chief executive, said "this is a significant and complex transformation that will introduce a single integrated patient record across our district".
Ms McCosker said extensive work had been done to introduce the new system, called the Single Digital Patient Record (SDPR).
She said this included digital infrastructure upgrades, large-scale testing and "the migration of more than one million patient records".
An insider said there was "a huge amount of stress and anxiety among staff surrounding this change".
"While the project has been promoted as improving patient care and communication between health services, many frontline healthcare workers are deeply concerned about how the rollout is being handled locally."
The insider said there were "significant concerns around patient safety and operational readiness".
Public healthcare workers were already under pressure from staff shortages and high patient demand.
The change is being managed by NSW Health's Single Digital Patient Record Implementation Authority (SDPRIA).
Staff from this authority, including Hunter workers, were concerned about heavy workloads.
They alleged there was "non-stop pressure from the executive and unrealistic demands and deadlines".
The Health Services Union (HSU) held a stopwork meeting among staff on Monday to discuss concerns.
Gerard Hayes, HSU NSW secretary, said "members at SDPRIA took this industrial action reluctantly and only because workloads were unsustainable".
"Since taking the action we've had promising signals from management. It appears our message has been heard," Mr Hayes said.
"We look forward to resolving this issue as soon as possible."
Ms McCosker acknowledged that "there will be challenges as our staff adapt to new systems and workflows, particularly in the early stages of go-live".
"Patient safety and continuity of care remain our priority," she said.
"To support the transition, a 24/7 command centre will operate during go-live, bringing together clinical, operational, technical and patient flow oversight."
She said this would be coordinated with NSW Ambulance, the SDPRIA and US-owned software company Epic.
NSW Health signed a huge contract with Epic for the SDPR. Amazon Web Services will host the system on cloud servers.
Ms McCosker said additional support staff and specialist teams would "be deployed across most facilities to support front-line staff during the transition".
"This is a district-wide go-live, not a staged rollout across selected sites," she said.
"I want to recognise the enormous effort from staff across our district to prepare for this transition.
"While we expect some challenges, we're confident in the preparation and support structures in place to respond quickly to issues as they arise."
Dr Teresa Anderson, the SDPRIA chief executive, said "the wellbeing of our staff remains our priority".
"We are continuing to work on strategies to support them," Dr Anderson said.
"We are also committed to continuing to work with the Health Services Union to address any concerns raised by its members."
