Mr Metzler went on the front foot over the past few days about the role of physician associates in New Zealand’s medical system.
There were four physician associates working at Gore Health, all trained in the United States, and vastly experienced medical professionals, Mr Metzler said.
A physician associate was a loose term for a person who worked in with a doctor in various roles to improve the health of patients.
The government was considering regulations around the associates’ roles but medical unions had raised concerns about the associates and their place in the medical system.
New Zealand Nurses Organisation chief executive Paul Goulter said in a statement the government needed to support the development of "our own culturally competent health workforce" and do more to keep nurses in their jobs.
"That includes fixing pay parity for primary care nurses — not introducing another unregulated workforce to do work that can and should be done by qualified nurses and doctors," he said.
"There is no need to introduce physician associates into New Zealand as a quick fix to the doctor shortage or the shortage of nurses. That funding could be used to incentivise and support more nursing students to graduate, get good jobs and to free up the staffing bottlenecks within Aotearoa."
He said the British Medical Association’s general practitioners committee for the United Kingdom had voted in favour of stopping hiring physician associates in general practice and for existing roles to be phased out.
Other health unions such as the Association of Salaried Medical Specialists (ASMS) and and the Royal New Zealand College of General Practitioners have written to Minister of Health Dr Shane Reti before he brings any formal proposal on physician associates to Cabinet.
ASMS executive director Sarah Dalton said there was no task that a physician associate would potentially perform that was not already being undertaken by a regulated health worker who was already trained and employed in New Zealand.
"Right now it appears the government is not providing the funding to employ enough doctors and nurses. The last thing we should do is spend time and money setting up a new system of vocational registration for a whole new profession when the government isn’t currently spending enough to fund the existing workforces."
Mr Metzler said the reality in the New Zealand health system was that the country was not producing enough nurses or GPs so everyone was needed to help the system.
"I get something new — physician associates — does create a bit of fear. But they are not new. They have been around in the US since the 1960s, started out at Duke University. They are 60 to 70 years old.
"There are 180,000 of them in America — the most litigious health system in the world, and they have lasted."
Mr Metzler said the associates did not do the job of the doctor. They simply freed up things for the doctor and made the doctor’s job easier. They worked as part of a medical team which all worked for the health of the patient.
They had 27 months of training, all with health background and bachelor of science degrees and all in Gore had at least seven years’ experience.
He said it was misleading to say the associates were likely to be forced out in the UK as the associates themselves were backed by other parts of the medical system.
Mr Metzler said the medical unions were simply protecting their patch but they had to look at the bigger picture.
"We are 500 GPs short here in New Zealand. It is going to be 750 in three years. This is an alternative as we are going to be on our knees.
"Australia has just loosened its entry levels for GPs so we are becoming a breeding ground for them. We are just becoming a recruitment pathway for them.
"The PAs have been here for 12 years and in that time there has not been a single time where there has been a health and disability commissioner or a clinical complaint against them.
"If I could I would like to have another five of them."
Without them he said the 24/7 emergency service in Gore could not operate.