Rotorua patients have been left waiting and healthcare providers are rearranging their routines ahead of next week's junior doctors' strike.
The Lakes District Health Board employs 93 resident medical officers, most of whom are members of the Resident Doctors' Association, who will walk off the job for 48 hours from 7am on Tuesday.
Yesterday the RDA announced plans for a second national strike between January 29 and 30.
The union gave notice of next week's first national strike on New Year's Eve.
It said DHBs were trying to reverse some of the improved working conditions junior doctors secured after the 2016 strike action, but the DHBs said past negotiations about stress and fatigue were appropriately considered.
Lakes DHB has cancelled elective and scheduled surgeries, affecting 20 patients across the two days, and outpatient clinics, affecting 350 people.
It hopes to reduce the number of people in Rotorua and Taupō hospitals and ensure staff can focus on those most in need in the emergency departments during the strike.
Acting chief executive Nick Saville-Wood apologised to affected patients.
He said contingency planning meetings had been held for several weeks.
"Changes to hospital operations are considered necessary to ensure the safety of our patients and staff."
Lakes DHB is part of the Pinnacle Midlands Health Network.
The network's medical director, Ōpōtiki-based general practitioner Dr Jo Scott-Jones, said it was "frustrating for everybody when elective surgeries are delayed or cancelled".
"It's not just elective surgeries, there are a whole range of investigations and tests that are affected by each strike".
He said GPs would continue to use the variety of tools they had to keep people out of hospital.
"In terms of strikes, the work for GPs doesn't usually change an awful lot, but referral processing times can take much longer. But if someone comes into my clinic during a strike with chest pains, they will be treated just the same urgency as they normally would be... I would imagine it's [dealing with strikes] becoming familiar territory".
Yesterday, Diabetes New Zealand Rotorua spokeswoman Karen Reed said she had not yet heard from patients affected, but "inevitably there are going to be people with diabetes affected in the DHB".
"We possibly might hear afterward."
Rotorua Hospice spokeswoman Nicola Smallwood said: "We have a really close relationship with the hospital but as we have our own clinical team and a number of GPs we work closely with, it won't affect our day to day operations."
Lakes DHB strike advice - Make sure you are up to date with prescriptions. - If you have minor health issues, make you GP the first port of call. - You can also contact Healthline on 0800 611 116 for advice from a registered nurse. - Patients affected this week have been notified but uncertain patients can ring 0800 223 647 to check.