Wellington Regional Hospital and hospitals throughout the South Island have been discharging patients and cancelling non-urgent surgery to free up beds for patients injured in the Christchurch earthquake.
The 6.3-magnitude devastating quake hit the central city at 12.51pm, causing several deaths and many injuries.
Christchurch Hospital is open and only one ward was damaged. The Blood Service said it had sufficient stocks of blood available and did not need more donors.
Wellington Hospital said it was on stand-by to help and had cancelled all elective surgery for Wednesday, as well as discharging patients who could go home.
The Southern District Health Board said Dunedin Hospital was also discharging patients and is on stand-by.
A spokeswoman says it had postponed elective surgery for Tuesday afternoon and Wednesday.
It was asking people in Dunedin to visit their family doctor rather than the hospital emergency department if possible.
In Timaru, South Canterbury DHB said two patients who were on the way to Christchurch Hospital were turned around and would be cared for at Timaru instead.
It said St John Ambulance had asked to bring three patients to Timaru Hospital by road.
The DHB said the quake was felt in Timaru, but there were no serious issues or equipment failures there.
Nelson Marlborough DHB said it was postponing elective surgery on Wednesday.