An investigation has been launched after nine patients at a hospital in the North West were operated on with surgical instruments which had not been fully sterilised.

Wirral University Teaching Hospital Foundation Trust has confirmed the incidents took place between 12-15 January and saw instruments used in both minor and major surgical cases despite not being fully sterilised between operations.

The trust has identified nine patients who were potentially put at risk of infection during procedures including a skin biopsy and major hip replacement surgery.  

The trust said the patients were at “extremely low risk” of infection and that all had received apologies.

HSJ understands instruments used in surgery were due to undergo a three-stage decontamination process but the third stage was not completed.

The trust has insisted the error was not caused by a technical fault in the sterilisation system or was a result of low staffing levels in the sterile services department, which it said were correct at the time.

In a statement to HSJ the trust said staffing levels had not been reduced.

Trust medical director Evan Moore said: “The instruments were highly disinfected but not sterile.

“Immediate action was taken and the medical instruments affected were identified. Not all of the affected items had been used.”

He added: “The patients were at an extremely low risk of infection. The level of risk was determined in consultation with infection control and virology experts and Public Health England. The consultant and senior nurse in charge of their care had a face-to-face meeting with the affected patients to apologise and fully explain the situation, and give them reassurance.”

He said “rigorous” training and support were being offered to staff, while a detailed internal investigation was being undertaken “to identify the cause and ensure there is no repetition”.

Dr Moore added: “On behalf of the trust I would like to apologise for this omission and give assurance that no other patients have been affected.”

HSJ reported last week the trust’s human resources director had lost her job, despite a disciplinary investigation finding she had no case to answer.

Sue Green, who was suspended in October, was made redundant after the trust decided to “streamline the executive structure”.

Wirral refused HSJ’s request that it provided evidence of the decision-making process that led to Ms Green’s post being removed from the board.