The nurse had been employed by the DHB as a registered nurse for four months, and this was her first job as a registered nurse.
A mental health support worker and another registered nurse were also present in the de-escalation area, together with another client. The clinical co-ordinator and senior registered nurse in charge were also on duty in different but nearby areas of the unit, Mr Hill said.
The woman began swearing and acting aggressively, so the nurse told the woman to go to her room for time out. The woman went to her room, then returned and demanded a hot drink, Mr Hill said.
The nurse told the woman that she would make her a hot drink if she calmed down and the woman then approached the nurse and punched her several times on the left side of her head, leaving the nurse's ear bleeding.
The nurse responded by punching the woman at least twice on the upper part of her body.
The woman was restrained and with the agreement of the senior registered nurse, the nurse administered an injection to calm her and she was then escorted to her room and put in isolation.
The nurse declined to see a doctor and no formal debriefing was held with any staff, Mr Hill said.
In his investigation Mr Hill found that the nurse failed to provide services with reasonable care and skill when she punched the woman.
He said it was held that the DHB was not vicariously liable for the registered nurse's actions, nor was it directly liable for the assault on the woman.
Mr Hill also made adverse comment in regards to the DHB, the Clinical Co-ordinator and the senior registered nurse in charge in relation to events following the altercation.