The following week, on September 23, Rachel took a much bigger overdose and was admitted to Hutt Hospital.
Intensive care expert Dr Catherine Simpson, who led an external review of the hospital's treatment of Rachel, was critical of the decision not to put Rachel in the intensive care unit, even though a bed was available.
She said the cardiac care unit nurses were highly skilled, but they were also highly specialised and did not have access to the drugs and equipment available in intensive care.
Dr Simpson said cardiac unit staff had accepted Rachel as their patient because of the hospital's "culture of coping".
"They felt that they couldn't say no."
She said the same culture meant none of the staff contacted senior consultants until later, by which time Rachel had been suffering seizures for almost 45 minutes.
Dr Simpson was also critical of the lack of urgency in the care provided.
When Rachel suffered her first seizure, staff should have realised that was unusual for the relatively safe drug she had taken - and her second seizure should have alerted them they were "now into uncharted territory".
But staff had not checked the national poisons database, and were not used to routinely dealing with overdoses, like the intensive care staff were.
When Rachel's seizures resumed for a third time and did not stop - a condition known as status epilepticus - staff focussed on trying to stop the convulsions.
Instead, they should have focussed on ensuring she was getting enough oxygen.
They finally inserted an oxygen tube almost 45 minutes later, by which time Rachel had suffered a cardiac arrest. She died the following week, several days after her life support was switched off.
Hutt Valley District Health Board's clinical head of anaesthesia and intensive care, Dr Peter Tobin defended the decision to put Rachel in the cardiac unit.
"In the circumstance I believe that was a reasonable decision to make. She didn't need intensive care treatment initially."
He said hospital transfers took a long time to arrange and until the diagnosis of status epilepticus was made, it was unclear whether Wellington Hospital would have accepted Rachel.
Questioned on what could be learned from the culture of making do, Dr Tobin said communication was the key.
That involved junior staff stating clearly whether they were asking for advice, updating senior staff on a situation, or asking for help.
He said the hospital was saddened by Rachel's death.
"I think all of the doctors and nurses involved in her care at the hospital were doing their utmost to get a good outcome for her. Just sometimes we can't achieve that."
The inquest concluded this afternoon with Coroner Garry Evans advising that he will reserve his findings.
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