An emergency doctor at Wellington's Hutt Hospital says they are often operating with just half the number of people they need, adding to a backlog of ambulances queuing up outside the department.
The equivalent of nine ambulances a day are unable to respond because they are stuck outside emergency departments, unable to drop off patients.
It's known as ramping, and in the first three-months of this year, Hato Hone-St John Ambulance crews spent more than ten thousand hours queued up outside.
Hutt Hospital Emergency Doctor and Association of Salaried Medical Specialists member Tanya Wilton tells Charlotte Cook it's a complex problem that has far reaching ramifications.