The coroner investigating the death of Aishwarya Aswath has questioned why it took such a tragedy for staffing concerns at Perth Children's Hospital to be addressed.
An inquest on Thursday heard nurses had expressed alarm about staffing at the hospital shortly before seven-year-old Aishwarya died of sepsis.
On March 9 last year, two emergency department nurses wrote to union boss Mark Olson outlining the strain they were under.
Mr Olson said the staff had warned of times during resuscitation events when two nurses were left to oversee 40 to 60 patients.
"What struck me was that it was a disaster waiting to happen," he told the inquest.
"I find that terrifying - two nurses to look after 40 to 60 patients."
Mr Olson met with dozens of nurses on March 29 - days before Aishwarya's death - to seek more feedback.
The Australian Nursing Federation WA chief executive said staff had raised concerns with managers as far back as October 2020.
"Desperation was the word that comes to my mind," he said.
Deputy state coroner Sarah Linton said it was becoming increasingly clear from the evidence at the inquest that nurses "were run off their feet and doing too many jobs for one person to do in a safe and sensible way".
"It raises this whole issue of why does it take a death," the coroner said.
"The problem is there weren't enough staff, according to the staff who were on the ground."
After Aishwarya's death on Easter Saturday last year, the union put forward a 10-point plan aimed at improving safety in the Perth Children's Hospital emergency department.
Mr Olson said while most of the recommendations had been progressed, there was still no dedicated resuscitation team at Perth Children's Hospital and the government had declined to implement nurse-to-patient ratios.
He said the casual nursing pool had been "decimated" early in the COVID-19 pandemic and those workers had not been eligible for JobKeeper.
Nurses had resorted to turning off their phones because they were constantly asked to work additional hours.
Mr Olson's evidence drew objections from Carolyn Thatcher SC, representing Perth Children's Hospital.
"This is going down a very troubling path ... is this inquest about the ANF campaigns or is it about the death of a child?" Ms Thatcher said.
The coroner disagreed, saying it was relevant context.
A shift coordinator this week told the inquest there had been one nurse for every nine patients on the night Aishwarya presented to the emergency department.
Expert witness and former WA chief nursing officer Phillip Della described that workload as "impossible", saying it would force staff to ration care.
He said a ratio of one nurse to three patients was more appropriate and had been implemented in pediatric emergency departments in other states.
WA does not formally enforce nurse-patient ratios, instead calculating nursing hours per patient per day.
Professor Della said that model was flawed because it did not account for indirect care, the layout of the hospital or the skills and experience mix among staff.
Perth Children's Hospital nursing coordinator Susan Baker said there had been an "unprecedented and unexpected" increase in presentations in the lead-up to Aishwarya's death.
She said the hospital had been trying to recruit staff from overseas at the time but had been hampered by WA's closed borders.
The coroner will hear closing submissions on Friday.
