A woman who had a mastectomy at a private hospital ended up needing a skin graft after she was burned while lying on a warming mattress during surgery.

An internal investigation carried out by Hamilton’s Braemar Hospital, found a warning alarm from the mattress was ignored twice during the surgery by theatre staff, who instead overrode the alarm and turned the mattress back on.

​Now, Health and Disability Commissioner ​(HDC) Morag McDowell​ has ruled Braemar Hospital had a duty to provide an adequate standard of care to its patients, which it did not do.

“I am not satisfied that all precautions were taken to prevent the burn, and it was not acceptable to have ignored the alarms and reset the warming mattress.

“This failure involved several people within the theatre team, and it is appropriate for Braemar Hospital to be held accountable for that failure.”

Woman needed skin graft following masectomy

According to a decision released today the woman, who has not been named, underwent a mastectomy on July 26, 2023 at Braemar Hospital.

During the surgery, she was positioned on a warming mattress.

The mattress is a pad placed between the patient and the operating table and is set to 35-39C to maintain a person’s normal core body temperature during surgery.

At the end of the surgery, the woman was transferred on to a ward bed and irritation was noted across her right hip, buttock and thigh.

Staff then realised it was a 15x10cm burn.

The anaesthetist immediately contacted a plastic surgeon, who established that the woman had sustained a thermal burn, which would require a skin graft to heal.

The woman underwent skin graft surgery on August 10, 2023 with a different provider and laid a complaint with the HDC about the care she received from Braemar Hospital.

Braemar Hospital told HDC that the patient’s skin must be in direct contact with the mattress sensors.

The control unit, which operates the mattress, has several audible and visual alarms to indicate issues with the mattress and/or control unit.

If an alarm is triggered, an error code appears on the screen and the heating function automatically turns off.

When the mattress is set and/or reset, it starts a gradual “warming-up process”, during which it can “spike” up to a temperature of 43C before settling at 39C.

Health and Disability Commissioner Morag McDowell investigated the woman's complaint. Photo / HDC

The hospital was unable to determine the exact cause of the woman’s burns.

But an internal investigation found the most likely explanation was the placement of a saline bag under the woman’s armpit, which could have occluded or otherwise affected the heat regulation sensor on the mattress, causing it to alarm, which, when reset and reheating, caused a spike in temperature briefly to 43C.

Another explanation was that it could have been a combination of heat and pressure from the woman’s hip area, when positioned in the right lateral position for an extended period, which could have heated that area above the usual 39C, the decision said.

Alarm sounded twice during surgery

Braemar Hospital told the HDC that the mattress alarm was triggered twice during the surgery and that, instead of determining why the alarm had gone off, the staff overrode and reset the alarm and turned the mattress back on.

The hospital said this was common practice and had previously not led to any problems.

However, it acknowledged this was concerning and that theatre staff did not follow standard process. Braemar Hospital has been approached for comment.

McDowell said Braemar Hospital breached the Code of Health and Disability Services Consumers’ Rights, which the hospital accepted.

“Braemar Hospital had a duty to provide an adequate standard of care to its patients while adhering to its internal processes and to the Code, which unfortunately did not occur.”

She recommended that Braemar Hospital provide a written apology specifically related to the identified failings and the breach of the Code identified in this report to the woman.

She also recommended that staff be trained on the appropriate management of machine alarms as well as the management of pressure relief for patients when positioned in a certain way for extended periods.

Brianna McIlraith is a Queenstown-based reporter for Open Justice covering courts in the lower South Island. She has been a journalist since 2018 and has had a strong interest in business and financial journalism.