As he was wheeled into theatre for surgery to fix a broken right hip, grandfather-of-seven George Leeson was joking with the surgeon that he hoped he had ‘sharpened his knives’.
George, then 94 and a father of three, also cheerily told nurses that as soon as he recovered from the surgery for the break — the result of falling out of bed — he would be resuming his weekly dancing sessions and regular get-togethers with his family, during which he enjoyed nothing more than chatting about the prospects of his beloved Arsenal football team.
But none of this would happen. In fact, George’s light-hearted exchange with the medical team would be one of the last truly coherent things he would say.
When his daughter Anne, 63, a paediatric nurse from Lincoln, visited him two days after the operation, she found ‘an utterly different person to the one who went into theatre’. ‘It was as if the operation sent Dad mad,’ she says, bluntly.
Although lucid when he came round, on December 28 last year, ‘he was sitting up in bed and drinking tea,’ says Anne — the next day he ‘wasn’t making any sense’.
‘He was saying things like, ‘The X and the Y is joined to the Z’ or, ‘The answer you seek is behind the curtain’,’ she recalls.
‘It was so hard to see Dad like that — especially as three days before, he was at my house celebrating Christmas, chatting with everyone as normal.
‘It was as if he had a personality change and it was really upsetting,’ says Anne, who is married to Ian, 63, a sales consultant, and has two grown-up daughters.
‘No one could tell me how long he would be like this for — I went home very distressed.’
George was diagnosed with post-operative delirium. It is the most common complication of surgery for older patients but can strike younger people, too — with tens of thousands affected each year.
Typically, delirium occurs 24 to 72 hours after surgery and, while some patients may become restless, confused and aggressive, others may seem sluggish and show little awareness of what is going on around them. Some may hallucinate.
The risk of developing delirium not only relates to age and type of surgery but also where you live, as rates seem to vary from hospital to hospital.
And while, for some, it’s temporary, lasting days, for others it’s a more enduring problem.
A study published in March in JAMA Internal Medicine, involving more than 560 patients aged over 70 with post-operative delirium, found they declined cognitively quicker over the following six years than those of a similar age who either had surgery and no delirium, or had no surgery.
Those affected are also three times more likely to require care after their discharge from hospital, and 7 to 10 per cent of them die within a month, compared with 1 per cent of patients who don’t get it, according to a review in the British Journal of Anaesthesia in 2020.
And those affected are more at risk of long-term cognitive decline, ‘meaning patients become confused or their memory may suffer,’ says Ali Mazaheri, a neuroscientist and an associate professor at the Centre for Human Brain Health based at Birmingham University.
George was smartly dressed and cracking jokes when he was admitted to hospital on December 27, the day he broke his hip, and although showing signs of early Alzheimer’s disease, his only difficulty was retaining new information. But by the time he was discharged a month later he had to go into a nursing home, his former residential home no longer adequate for his needs.
‘Very occasionally he would open his eyes and say, ‘Hello dear,’ and be his old self for a moment,’ says Anne. ‘But most of the time he was saying mad things — he never recovered to his old chirpy self. It was awful to witness.’
Five weeks after his operation George died, having never walked again, regained the ability to feed himself or communicate properly with the family he held so dear.
But could a few simple measures have avoided all this?
For while post-operative delirium used to be largely blamed on the anaesthetic, now it’s known that many factors play a part, from the inflammation and pain triggered by the trauma of surgery to the environment and care in the immediate aftermath.
And, while drugs and other interventions are being investigated as ways of preventing it, it seems that minor changes to care have the biggest impact.
One is reorientation — making patients feel they are in a familiar environment — as soon as possible after surgery.
This reduces post-operative delirium risk by 40 per cent, according to research cited by scientists from Imperial College London and Zhengzhou University, China, in the British Journal of Anaesthesia in 2020.
But, judging from George’s experience, these measures are not always being followed. He was wheeled back from theatre to an acute orthopaedic ward and moved again in the middle of the night a couple of days later to a different orthopaedic ward.
Anne says she was ‘horrified’ to find a prisoner handcuffed to the bed next to him, with two prison wardens shackled to him.
What’s more, she adds, George spent the next month on a noisy, brightly lit ward where it was hard to tell night from day. It certainly wasn’t the ‘familiar’ environment that might have made a difference.
‘Delirium tends to arise when multiple things are not right, and the patient’s brain becomes overloaded and bewildered,’ says Antony Johansen, a consultant orthogeriatrician (someone who specialises in the care of older people with fractures) at the University Hospital of Wales, Cardiff.
‘For instance, a typical patient with a hip fracture is coping with pain, painkillers, a strange environment (especially when it gets dark), enforced bed-rest, worry about getting to the toilet, absence of family, unfamiliar food, or nil by mouth, and so on.’
Any one of these things can become ‘the last straw’ that tips the balance, he says.
Some experts believe the issue of delirium prevention does not get the attention it deserves. ‘There are more measures that could be introduced to identify who is at risk and more steps that could be taken to reduce that risk but I don’t think this is seen as a priority,’ says Dr Mazaheri.
National Institute for Health and Care Excellence (NICE) guidelines to lower risk, introduced in July 2010, include ‘keeping the environment familiar’, using ‘appropriate lighting’ [ensuring there are periods of light and dark to help sleep patterns], ensuring patients have adequate fluid and ‘mobilising’ them soon after surgery.
Tackling the problem is more important than ever, as advancing age is a key risk factor and the average age of surgical patients is going up all the time.
In 1999, the average age of a person having an operation in England was 47, and half a million people over the age of 75 had surgery. By 2015, the average age for surgery was 54, and more than a million over-75s a year underwent surgery.
Other risk factors include being male (possibly because of poorer general health), having multiple health conditions (diabetes, for example, may lead to inflammation and other changes in the brain if it is poorly controlled) and the type of surgery — the more invasive and lengthy it is, the greater the risk.
For example, delirium affects around 2 to 3 per cent of all surgical patients. But among those having hip surgery it can be up to 50 per cent, according to a review in the European Journal of Medical Research in 2022. This may be because these patients tend to be older and are often having emergency surgery (owing to a fracture). Rates can be higher still for some heart surgery because of the length and trauma.
Dementia, too — even in its early stages — is a risk factor.
‘I don’t think it is an exaggeration to say that it [delirium and its knock-on effects] is an epidemic in waiting,’ says Dr Mazaheri.
‘That’s because age is strongly associated with the risk and more people are living longer and so having more need for surgery.’
He believes the knock-on effects often go under the radar because patients pass through the system so quickly.
‘The NHS is great at fixing the complaint that required surgery but there’s a chance that you leave hospital with a host of other problems that are on no one’s radar. It is then over to social care.’
His own mother developed ‘severe’ post-operative delirium after surgery to remove a tumour in 2019 when she was 72.
She experienced ‘vivid and distressing hallucinations’ and, while she recovered, the impact ‘lingered with her until the day she died in 2021,’ he says. ‘It was especially traumatic for my elderly father, who struggled to comprehend what was happening.’
The experience so moved Dr Mazaheri that he switched his research focus to addressing the problem.
But the risk of developing post-operative delirium also appears to be something of a postcode lottery. According to the 2023 National Hip Fracture Data report, an audit of hip-fracture care and prevention in England, Wales and Northern Ireland, 38 per cent of the 72,000 hip-fracture patients monitored during 2022 were delirious when tested ‘promptly’ after surgery.
The rates varied enormously between hospitals, with some reporting no cases, yet others reporting more than 99 per cent were delirious.
The question is why is there such huge variation?
‘It’s partly down to differences in quality of screening,’ says Professor Johansen, who is also clinical lead of the National Hip Fracture Database at the Royal College of Physicians in London.
‘Some hospitals are still not screening any patients and have no idea how many are suffering from what is the most common complication of hip- fracture surgery.’
While delirium is relatively common, so too is post-operative cognitive dysfunction (POCD), a less acute after-effect which tends to become apparent in the weeks, or months, after surgery.
‘Whereas delirium is immediate and quite pronounced, post-operative cognitive decline is more subtle,’ says Mario Cibelli, a pain physician at Guy’s and St Thomas’ Hospital in London and also a specialist in cardiothoracic anaesthesia and intensive care medicine at Queen Elizabeth Hospital Birmingham.
‘Quite often, it is so subtle the person affected may not notice, just friends or relatives. But in the worst cases it can result in serious disability and more dependence on others.’
Risk factors for POCD include previous surgery, inactivity (which may influence the general health of the brain) and low educational attainment (thought to be linked with fewer connections, called synapses, between brain cells which protect the brain against the assault of surgery).
‘But even the most intelligent scientist may have other risk factors that mean they then get POCD,’ says Dr Cibelli.
Nor is it only the elderly who are at risk.
A study in the journal Anesthesiology in 2008, involving 1,069 people who had their mental reactions tested before and after a hospital stay for surgery, found that 5.7 per cent of those aged 18 to 39, 5.6 per cent of those aged 40-59 and 12.7 per cent of those over 60 had cognitive decline described as a ‘fogginess’.
For years the culprit for delirium, at least, was thought to be drugs used in anaesthesia — with a consensus that spinal anaesthesia (where patients are only partially numbed) was safer than general anaesthesia (where they are completely ‘asleep’).
‘But no one has proved that either way — there isn’t an advantage one way or another,’ adds Professor Johansen.
A 2021 study in JAMA, involving 950 patients over 65 who had surgery for a hip fracture, found no big difference in post-operative delirium rates in those given spinal anaesthesia and those who had a general anaesthetic.
Professor Robert Sanders, the Nuffield chair of anaesthetics at Sydney University, says: ‘We are finding it’s not the anaesthetic but the body’s response to surgery — particularly the inflammation that occurs from having an operation — and other events around the surgery that seem to provoke confusion.’
Work by Dr Cibelli, published in the Annals of Neurology in 2010, found, in studies on mice, that while there was no change in levels of inflammatory markers in the brain during anaesthesia, there was a change during surgery under anaesthesia, possibly because inflammatory chemicals are released by the immune system in response to tissue being damaged during surgery.
The theory is inflammation then makes the blood/brain barrier, the brain’s protective ‘fence’, more permeable, allowing those inflammatory chemicals into the brain where they can damage highly sensitive neurons (brain cells).
Even mild inflammation has been found to alter brain function.
For a study in NeuroImage, in 2019, Dr Mazaheri and his team gave a group of healthy men the salmonella typhoid vaccine to induce very mild inflammation.
‘We found the inflammation had an impact on the part of the brain related to alertness and one of the key things with delirium is the inability to maintain alertness,’ says Dr Mazaheri.
‘But the other interesting thing is that people with Alzheimer’s also tend to have a more leaky blood/brain barrier — we don’t know if it’s a cause or symptom.
‘That means if you have even mild dementia, you may be more likely to have delirium as your blood/brain barrier is leaky anyway.’
The theory is the delirium lasts until the blood/brain barrier re-strengthens and the brain ‘recalibrates’.
One way the risk of post-operative delirium can be cut, according to the 2020 British Journal of Anaesthesia paper, is by addressing pre-operative pain. Those in significant pain before surgery are up to three times more likely to develop delirium because pain ‘imposes a direct cognitive burden, triggers an acute stress response, and increases the risk of other postoperative complications,’ it said.
Dr Mazaheri is part of a multi-centre team running a trial to screen older patients awaiting surgery to predict — ‘based on their brain function before surgery’ — how much pain they will be in afterwards.
An electroencephalogram (EEG) will measure their brain activity to see if they are ‘pain sensitive’, he says. ‘If they are, we can give them more opiates during surgery so that they are less in pain when they come round.
‘You wouldn’t want to do it for everyone, as using opiates is associated with a risk of delirium too, but with this group of patients there will be a risk/gain benefit.’
Dr Cibelli, meanwhile, is running a trial using a new technique that delivers local anaesthetic to the fine nerves surrounding the wound site in the chest, in order to reduce post-operative pain in those having heart surgery, which has the highest post-operative delirium rate of any surgery.
The multi-centre trial is just starting. But Dr Cibelli says the patients he has tried it on have been ‘left incredulous’ by their pain control after heart surgery and cognitively they were ‘among the brightest patients recovering in intensive care’.
Dr Mazaheri’s research will also look at ways to identify — with cognitive tests before an operation — who will, and won’t, develop post-surgical delirium and post-operative cognitive decline, the idea being this could help with future guidelines about informed decision-making around surgery.
‘You can then say this surgery is an option but there is this risk you will develop these issues.
‘And if you find someone is vulnerable, you can take more steps to reduce their risk.’
Professor Johansen says despite the risks, surgery for older people is far safer than it once was.
‘Just having a broken hip can be enough to cause delirium, and risk of delirium is not a reason to delay surgery to relieve the patient’s pain and distress,’ he says.
‘When I started 30 years ago, one in ten older patients wouldn’t get an operation as they were viewed as too high risk. Nowadays, surgery and anaesthesia are so safe that pretty much everyone is able to benefit from an operation.’
For George Leeson, the option was surgery or a life of immobility and pain. As his daughter Anne says: ‘The operation itself was a success — it was what happened next that wasn’t.’
Had elements of his aftercare been managed differently, it might have been a different story.
Sarah Carter is a health and wellness expert residing in the UK. With a background in healthcare, she offers evidence-based advice on fitness, nutrition, and mental well-being, promoting healthier living for readers.
