Seven “very serious” medical errors were made at Suffolk and Essex health trusts within six months this year, sparking calls for action by a watchdog.

Cutting the wrong toe tendon during foot surgery was among three never events – named that way because they are “preventable” and should never happen – to occur at Colchester Hospital University NHS Foundation Trust between April and October.

A fragment of medical equipment was left in a patient in one of three incidents to happen at Ipswich Hospital within the same period.

A piece of surgical equipment used during an operation broke off and was left inside a patient – who was informed and made a full recovery – at West Suffolk Hospital.

Healthwatch Suffolk’s chief executive Andy Yacoub urged the trusts to learn from their mistakes and take action to prevent such errors from happening again.

“As ‘never events’ are serious medical errors, Healthwatch Suffolk would consider them to occur very rarely, if at all,” he said.

“They are defined as very serious, preventable and costly medical errors and as such we expect our local hospitals to pay a great deal of attention to them when they do occur. They must learn from them and act; informing all those who need to make changes in, for example, decision making so that the public can be assured that such occurrences will not be repeated.”

Details of never events are published routinely by health trusts via the NHS improvement service – bosses must record them and notify the relevant safety authorities.

Ipswich Hospital spokeswoman Jan Ingle said the trust was “disappointed” that the events occurred.

But she added: “No patients had long lasting or permanent damage because of them.

“We report all incidents using a national serious incident report investigation (SIRI) framework and we publicly report any incidents on our quality audit.”

And health chiefs at Colchester were keen to stress that one never event is “one too many”.

“It is right for each problem to be highlighted and for a solution to be found,” a trust spokesman said. “The trust is working hard to ensure that it embeds learning from never events, serious incidents and complaints throughout the organisation for the benefit of patients in the future.”

West Suffolk NHS Foundation Trust’s chief nurse Rowan Procter added: “The trust works extensively to ensure we are fully compliant with all national guidance related to ‘never events’ and supports the philosophy that they are wholly preventable. Patient safety is our top priority and we work with staff to continually improve our processes and procedures.”

For a list of never events across the NHS as a whole, visit improvement.nhs.uk/uploads/documents/NE_data_provisional_report_April_-_October_2016_FINAL.pdf