Hospitals around the country are delaying surgery as doctors and medical specialists are called on to treat burns patients.
The Ministry of Health said a number of district health boards have had to defer surgery to care for those affected by the deadly eruption on Whakaari / White Island.
Its deputy director-general for performance support and infrastructure Michelle Arrowsmith said hospitals were discussing how they could share resources.
"In the aftermath of the eruption, the Ministry has been contacted by a number of DHBs noting their need to defer surgery, and re-prioritise clinical resources to meet the demands for treating their burns patients," she said.
"DHBs are having to manage burns patients, as well as their normal unplanned care patient load and their planned care workload."
Auckland resident Robert Lloyd was due to have an operation at Middlemore Hospital, with a plastic surgeon, today.
He was about to stay with a friend close to the hospital yesterday when he learned his surgery had been cancelled.
"I was just about to leave my house with my bag when the phone rang and it was Middlemore Hospital saying your operation has been postponed, and they would be in contact with a new date," Mr Lloyd said.
He said he was told the hospital was focused on helping burns victims.
"I just went quiet because it was the second time I've been bumped and I was really looking forward to getting it done before Christmas. But I realise there are people from White Island that are in much greater need than I was."
Mr Lloyd said he had been waiting for three months to have the operation.
"I really don't expect to be seen before Christmas, not with what's going on at White Island. They'll be doing plastic surgeries after plastic surgeries, I'm sure, on multiple people. I just feel for them because they're going to be really busy."
Hospitals will be working directly with any patients affected.