There were 77 cardiac arrest calls on the last day of the heatwave on Friday, seven times the usual rate.
Holman said the heat-exhaustion cases and spike in cardiac arrests would continue for the next 24 hours to 48 hours, with the elderly and people with chronic illnesses still recovering from the heatwave. "They've had four days of incredible stress on their bodies without any time to recover and that's going to continue certainly in the next 24 hours."
Paramedics have also responded to more than 50 cases of children being locked in cars this week despite repeated warnings about the danger.
Holman said demand for ambulance services was up more than 20 per cent but there had been no delays in dealing with the most urgent cases.
- AAP