Fifty-seven patients underwent operations on the wrong part of their body last year due to NHS errors, figures showed today.

Data collected by the National Patient Safety Agency (NPSA) revealed there were 57 reports of "wrong site surgery" in 2009/10 - something the Government has pledged should never happen.

Wrong site surgery refers to an operation on the wrong limb or organ (for example wrong knee, wrong eye, wrong kidney) or on the wrong person.

Overall, there were 111 "never events" in England in 2009/10 - things that should never happen on the NHS.

After wrong site surgery, the second highest number of never events (41) related to misplaced feeding tubes in adults and children.

This puts patients at risk of being fed directly into the respiratory tract.

Data on never events from previous years was collected differently and cannot be compared, according to the NPSA.

The Department of Health today announced it was proposing an extension to the list of never events, taking it from eight to 22.

The overall list would include medical instruments and swabs left in the body after surgery, the wrong route of administration of chemotherapy, death or injury resulting from the transfusion of the wrong blood type and death by falls from unrestricted windows in places such as mental health hospitals.

Hospitals can have funding with-held if a never event occurs.

Health minister Simon Burns said: "Our recent White Paper makes clear that unsafe care is not to be tolerated.

"We are committed to extending the system of never events - things that are preventable and should never happen to patients in NHS care.

"We will introduce clear disincentives through non-payments, just as there will be clear incentives for quality.

"Across the NHS there must be a culture of patient safety above all else.

"These measures will help to protect patients and give commissioners the powers to take action if unacceptable mistakes happen."

NHS medical director Professor Sir Bruce Keogh said: "Never events by their very name should never occur in a modern NHS.

"The proposed list includes avoidable incidents with serious adverse consequences for patients.

"No one wants these to happen, therefore we will not pay hospitals when these events occur.

"This will send a strong signal to leaders of the organisation to learn from their mistakes so they don't happen again."