A coroner's inquest will determine how a 64-year-old woman died from a "shipload" of insulin while being treated at an Auckland hospital.
Heather Ann Bills died at Middlemore Hospital on January 2, 2013, six weeks after she was badly burned in an explosive house fire.
On the evening of November 22, 2012, she was pulled from the fire after neighbours braved the inferno to rescue her from an upstairs room of her Orakei home in Auckland.
While being treated at the National Burns Centre and intensive care, Bills at times expressed a desire to die, chief coroner Judge Deborah Marshall said at the start of the inquest at the Auckland District Court today.
However, her condition improved and she was expected to make a recovery.
Then in late December 2012, her health began to deteriorate.
She developed low glucose levels, thought to be caused by insulin.
Bills was not diabetic and had not been prescribed insulin, the court heard.
She suffered an irreversible brain injury and died on January 2, 2013, as a result of a massive hypoglycaemic event.
Investigating officer, Detective Senior Sergeant Ross Stephen Ellwood, said Bills' death was the first and only one of its kind in New Zealand.
He suspected Bills had been administered insulin by medical staff, the court heard.
"I have my own view as to whether [Bills] was injected or not, but my view is not important, it's what I can prove in court.
"I think she was injected," he said.
The court will also hear evidence suggesting that a tumour may have also been the potential source of insulin.
Ellwood said there was an element of doubt, based on expert medical opinion, as to whether she was injected.
"Everyone who had care of [Bills] was interviewed," he said, adding none admitted they had administered insulin.
However, "on the balance of probabilities", he said Bills may have been injected with a vial of insulin, or through an intravenous line.
There were three suspects as part of the criminal investigation, Ellwood said.
"We're looking at someone working in a hospital, potentially causing the death of a patient, and we can't have that," he told the court.
The police investigation into Bills' death remains open, and evidence and conclusions from the inquest over the next couple of weeks may be used for further criminal inquiries, the court heard.
Michelle Maher, Bills' daughter, told the court today that "without the brave actions of her neighbours, Mum's life would have ended in that house".
She acknowledged her mother, who enjoyed Cliff Richard and the Beatles, had a "long and difficult" history of mental illness, but no drugs or alcohol were found in her system when she was first admitted to hospital.
She said, through tears, that her mother was on a "long road to recovery" but was alive.
However, she said it was unacceptable for her to die suddenly in hospital the way she had.
She agonised over how her mum "groaned and gasped to her death over three tragic days".
Maher said her mother's low blood-sugar levels were twice "missed" by the medical team.
"My mum did not deserve to die in hospital like that, and my family deserves to know the reasons and circumstances."
She said there was a "unanimous consensus that my mother had been administered insulin".
Maher said at a meeting with doctors on January 4 it was discussed that a "shipload of insulin" was needed to "record such low blood sugar levels".
"Was the reading an error or a deliberate act?" She said. "Would Mum have fully recovered if treated promptly?"
She said her family wanted "clear and direct answers" to the circumstances before and after her mother's death.
If it is found that there was deliberate, careless or unprofessional conduct, "we expect those individuals to be held accountable for their action or inaction", she said.
Bills, a small business owner and a "great cook", also had a son and five grandchildren.
"Tragically my children will never get to know their nana or share a famous bowl of her soup," Maher said.
Judge Marshall said it was not the role of the coroner to establish criminal or civil liability, but rather to determine what caused Bills' "sudden deterioration".
She said it was also for her to determine why the glucose levels were not detected earlier, and what was the source of the insulin.
"If it was administered to Mrs Bills who administered it?" Judge Marshall said.