Hawke's Bay Hospital in Hastings is operating at capacity and is cancelling some elective surgeries in coming days.
Acting chief executive Sharon Mason says demand for hospital services has been unrelenting since Christmas, with a record 170 people being seen at the emergency department on New Year's Day.
The previous record was 169 in July 2017.
The busy emergency department has increased the number of acute surgeries, forcing the hospital to cancel some elective surgeries in the early part of next week.
People with minor injuries and illnesses should see a general practitioner and leave the emergency department for emergencies only.
The hospital is expected to remain at capacity next week.