When a teenager was rushed to a rural hospital after a 2014 car crash, staff thought she was drunk.
It was only after family complaints and a police-requested blood test showed no alcohol in her system that the woman was transported to a city hospital's intensive care unit, where she later died.
The findings were part of a 108-page report released by Health and Disability Commissioner Anthony Hill after the woman's family complained about the level of care provided.
Mr Hill said the ambulance service, the rural hospital, a rural doctor and two nurses failed the teenager, providing poor care.
The 18-year-old woman was part of a single-car accident on the East Coast. The other occupant of the car was also injured, but was transported to a city hospital.
An emergency medical technician transported the woman, without any assistance, to a rural hospital. She was admitted about 4.45am.
On her arrival, she was unable to weight bear, expressed pain, and was reported to be drunk.
The rural GP at the hospital said the woman would not be transferred to the city hospital because she was drunk.
A nurse then performed baseline observations on the woman, but did not complete any neurological observations. The doctor assessed the woman, and said she had no obvious brain injury.
During the morning shift, broken glass on the woman's back was not removed and her hygiene needs were not taken care of.
When the registered nurse provided her handover to a second nurse, she failed to provide information on the patient.
The second nurse failed to conduct observations or start cooling cares for about six hours, and she was not offered food or any means of hydration.
It was only when family expressed concern that the second nurse contacted doctors, and she was eventually transported to a city hospital.
The woman underwent brain surgery and received brain-orientated intensive care therapies before dying in hospital.
The report said the doctor and the two nurses all made retrospective additions to the clinical records without noting them as such. The second nurse also removed original notes from the woman's file.
Mr Hill said the ambulance service failed to provide reasonable care and skill with the woman, and failed to recognise the seriousness of her condition.
He said the first doctor failed to recognise the woman's "significantly abnormal" neurological condition, stating her failure to improve over time suggested alcohol was not an explanation.
The first nurse failed to complete neurological observations and an assessment of the woman's blood glucose level, which Mr Hill said was another failure, while the second nurse did not monitor her vital signs for several hours.
He was concerned with how the second nurse failed to manage hygiene, food and hydration needs.
The doctor involved has been ordered to undergo a performance assessment, and there may be a review into the competence of the two nurses.
Mr Hill has referred the ambulance service and the owner of the rural hospital to the Director of Proceedings to decide whether any further action should be taken.
He has also recommended that those involved issue apologies to the family.
Dr Tony Smith, the medical director of St John, said the ambulance service was sorry for their part in failing to provide the best possible care.
"All of our sympathies go out to the patient's whanau and loved ones, who we have met and continue to communicate with," Dr Smith said.
"This case has also affected many St John staff, and we have taken every possible step over and above the HDC recommendations to ensure that something like this is never repeated.
"We wish to assure the public that we take patient safety and wellbeing extremely seriously, and have taken learnings from this tragic case to improve the service we deliver in rural areas and throughout New Zealand."