The Northland DHB says a field hospital in its pandemic plan is "extremely unlikely" to be used.
Whangārei Hospital was already struggling with booming populations, undersized departments and dilapidated infrastructure before the pandemic.
It plans to dedicate three wards and a unit to Covid-19-infected people, and a field hospital if more than 97 cases need admission.
But chief executive Dr Nick Chamberlain told RNZ staffing beds would be the hardest part.
"Finding an additional, significant number of staff to staff a field hospital would be a challenge. And you might say: 'well, maybe we could call in various other agencies' but everyone at the moment is constrained with workforce issues."
He said the DHB was more likely to use offices than tents for a field hospital.
"We might use one of our existing facilities such as the office block that I work in, Tohorā House."
Although he said a field hospital option had "always been in pandemic plans" it would be "the end of the line".
"It's actually extremely unlikely."
The DHB's bed space is already under huge pressure - the hospital was at 100 percent capacity earlier this month, without an Omicron surge.
One in 10 Northlanders have still not had a Covid-19 vaccine.
The Ministry of Health said although field hospitals had not been set up to date anywhere in the country, some DHBs "have set up marquees outside their EDs to act as triage areas to support the assessment, testing and streaming of patients during the Covid-19/Omicron outbreak".
"Currently, DHBs have been able to find suitable equipment from private companies and have been able to staff the extra space appropriately."
New Zealand Defence Force chief medical officer Lieutenant Colonel Charmaine Tate said staff had not been "formally asked" by the Ministry of Health to help with field hospitals.
"The NZDF is limited in what it can offer in this regard and does not have a standalone field hospital with accompanying medical staff that are standing by. Most NZDF medical staff for a field surgical facility are reserves who currently work in the civilian health system."
She said staff also needed "to maintain a surge deployable health capacity to support NZDF operations offshore".
And when asked what a field hospital was, she said in general, it was "a colloquial term that can describe a range of temporary and often portable medical facilities ... from simple tents in which to triage patients, through to more complex temporary surgical facilities that are focused on damage control surgery of combat casualties".
"In Covid outbreaks overseas, the generalised term 'field hospital' has sometimes meant an area of tents or marquees outside the entrance to a hospital for assessing patients on arrival, through to an 'overflow' area for patients where there may not be room to admit them to a ward. These overseas Covid facilities are usually a mix of military or civilian equipment such as tents and stretchers and potentially a mix of military and civilian health staff."
The government predicts the Omicron outbreak will peak in mid to late March.
RNZ
