The report also revealed that the number of patients arriving at the hospital by ambulance increased by 13.2 per cent over the same period.

During January to March 2018 a total of 11,650 patients presented to Maitland's emergency department. That increased over the same quarter this year by 1109 to 12,759 patients.

The increase at Maitland was reflected in hospital emergency departments across the State with the report showing that more people attended NSW emergency departments during January to March than in any previous quarter on record.

Across the state, there were more than 750,000 emergency department (ED) attendances, an increase of 5.9 per cent from the same quarter in 2018.

Locally, there were 20,947 presentations to the John Hunter Hospital ED, up 7.8 per cent from the same time last year. The Calvary Mater Newcastle had a 10.7 per cent increase in the number of presentations and ED attendances at Belmont Hospital rose by 9 per cent. Cessnock experienced an increase of 4.6 per cent.

The number of patients who were treated and discharged from the John Hunter Hospital ED within four hours had dropped to 64.7 per cent. Those treated and admitted in four hours or less dropped to 36.9 per cent, and 84.4 per cent of patients left without or before completing treatment.

"Emergency departments across the state experienced high demand during the quarter, particularly from patients triaged as emergency or urgent, while there was also a notable 10 per cent increase in arrivals at emergency departments by ambulance," BHI chief executive, Dr Diane Watson, said.

"At NSW level, the timeliness of care provided to patients has declined from last year. The results vary across hospitals - with some experiencing bigger drops than we see at NSW level, while others had stable or improved performance despite increased activity."

AMA (NSW) President, Dr Kean-Seng Lim, said that in less than 10 years, there has been more than a 40 per cent increase in the number of patients presenting at NSW emergency departments.

"We've just seen another all-time record for ED presentations set, and this time it peaked above 750,000 patients for the first time.

"It's also the second all-time record to be set in as many quarters," Dr Lim said.

"This is not a sustainable rate of growth in patient numbers - we have effectively seen one-tenth of the population of NSW go through our emergency departments over the first three months of this year.

"Our hospitals were not built to cope with this extraordinary level of demand and that is showing in the increased time to treatment and patient waiting times," he said.

"We need to help people find better ways to prevent development of diseases like type two diabetes.

"And we need to help health services in the community, like general practices, better take on the changing needs of the people they serve.

"This last point is something successive Federal Governments have been ignoring or making worse for several years now, through measures like the Medicare rebate freeze, and raising the spectre of co-payments," Dr Lim said.

The report shows about seven-in-10 ED patients were treated within clinically recommended timeframes across NSW hospitals, and 70.6 per cent spent four hours or less in EDs.

NSW Ambulance also experienced a busy quarter with more than 300,000 responses, up 10.2 per cent from last year. More than 136,000 ambulance responses were categorised as emergencies and more than 6000 were life-threatening cases.

"While we did see increases in response times for the broader emergency category, the median response time for life-threatening cases remained stable at seven and a half minutes."