NURSES should be banned from working 12-hour shifts in hospitals and care homes because they are dangerous and create a risk of "compassion fatigue", an expert has said.

Angela Kydd, a clinical professor of nursing at Robert Gordon University, previously advocated for the extended shifts to curb the problem of nurses working extra hours without pay.

However, she said she no longer believed that 12-hour shifts are in the best interests of patients or staff.

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Speaking to the Times, she said: "I am adamant that a 12-hour nursing shift is dangerous. It is bad for staff health. It is bad for wellbeing. How can you care for someone for 12 hours?

"If someone calls you at your 11th hour and says 'can you help me', how much more can you give?"

It is standard practice for NHS nurses to work 12-hour shifts in exchange for receiving more days off.

A typical monthly pattern includes three weeks of three days and one week of four days.

Some staff like the set-up because it helps with childcare arrangements or gives them the opportunity to earn extra money by offering their services to nursing agencies.

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Professor Kydd, 61, who trained as a nurse in England before moving to Scotland in 1990, added: "I would argue that you can only drive a lorry for so many hours and then you have to stop and the same applies to nursing."

Trade union Unison opposes 12-hour shifts. Matt McLaughlin, a regional organiser, said that as the profile of the nursing workforce had aged they were less keen on the long hours.

He said: "Fundamentally, with the shortage of nurses, the ageing workforce and changes in our lifestyles, this is an issue which needs a radical review."

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Norman Provan, associate director for the Royal College of Nursing Scotland, said: "Twelve-hour shifts should be considered in the context of both patient safety and the physical and psychological demands of shift work."

Jeane Freeman, the Scottish health secretary, said: "This is a complex issue, which the Scottish government takes seriously.

"The chief nursing officer's Nursing Vision 2030 has highlighted that shift patterns will need to be reviewed to support nurses to maintain good health.

"The health and wellbeing of NHS staff is paramount and fundamental in ensuring good outcomes for the people of Scotland."