The hidden long-term risks of surgery: "It gives people’s brains a hard time"

Cibelli listened as the woman described how her father, a former physics professor, had shown signs of significant cognitive decline after the initial operation. Once a keen chess player, he was now unable to play the game and struggled to even do basic crosswords.

For Cibelli, it was the first time he had encountered what is now termed postoperative cognitive dysfunction (POCD) – cognitive problems associated with surgery that persist well after the effects of anaesthetics have worn off. “I published some articles on the subject,” he says. “And people began finding my email address, saying their father or mother had changed a lot after a surgery in the past. So I began to realise that this wasn’t such an isolated case.”

We have known for a long time that operations can have hidden consequences for the brain. As far back as 1887, the British Medical Journal published a paper describing cases of delirium after surgery with anaesthesia. A century later, scientists in the 1980s began to look at cases of older patients who had shown a decline in memory and concentration after cardiac surgery, but it has only been more recently that this has become apparent as a risk factor for all over-65s who undergo surgery, especially when under deep sedation.