They finally gained entry with a fob key from refuge centre staff after Toko-Harieta Maki harmed herself, Northern Territory Coroner Elisabeth Armitage was told in Darwin on Monday.
Police put 33-year-old Ms Maki in handcuffs behind her back to stop her ongoing self-harm attempts as paramedics struggled to treat her, counsel assisting Chrissy McConnel said.
The coroner is examining whether authorities met their obligations in attending to Ms Maki who was at a centre in the Greater Darwin area.
The court on Monday heard the triple-zero call made by Ms Maki on July 25, 2024, in which she said: "I am saved by the Lord Jesus Christ".
The operator told her to unlock the door and wait for help to arrive.
The court heard one ambulance set to attend had mechanical issues so a second crew was called but faced a further delay due to a locked gate at the refuge.
CCTV footage shows two paramedics enter the room before exiting 33 seconds later, closing the door and immediately calling police to say Ms Maki was still actively self-harming.
The door was then locked.
The court heard Ms Maki, a New Zealander, had been assessed at Royal Darwin Hospital overnight before getting a room at the refuge.
Ms Maki was upset she would not get custody of her son, the court heard, and the next morning she self-harmed and made the triple-zero call.
When her door was unlocked an hour after the call she was handcuffed and given a sedative but went into cardiac arrest and could not be revived, Ms McConnel told the court.
Ms Maki had a history of mental health, self-harming, domestic violence and alcohol addiction issues, the court heard.
The inquest will examine whether agencies recognised the level of risk in the case of Ms Maki and whether they moved fast enough to respond.
That included questions over the hour-long delay in reaching her after the triple-zero call.
A lawyer for St John Ambulance told the court the paramedics who attended were confronted by a highly distressing scene but they provided the best care they could in trying circumstances.
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