Every year, hundreds of Australians suffer delirium after surgery but the frightening episodes are dangerously under-diagnosed, a senior anaesthetist warns.
Subscribe now for unlimited access.
$0/
(min cost $0)
or signup to continue reading
Delirium is a sudden spell of intense confusion and inattention, which can last hours, days or weeks and has recently been found to signal longer-term, catastrophic outcomes for patients, such as dementia.
Associate Professor David A Scott, the head of Anaesthesia and Acute Pain Medicine at St Vincent's Hospital in Melbourne, said it affects more than 40 per cent of elderly surgical patients.
The group most likely to become delirious are older people, or those already with cognitive impairment, who undergo common heart, vascular or hip surgery, he said.
Associate Professor Scott, who is also the incoming president of the Australian and New Zealand College of Anaesthetists is urging his peers to look out for the signs of delirium and take precautions with high-risk patients.
"Everyone thinks they know what delirium is but 75 per cent of delirium is missed post-operatively," Associate Professor Scott said.
"We need to know much more about it because it's common, it's damaging [and it's] definitely associated with longer term outcomes.
"Is it a cause or an indicator? In reality it probably is a bit of both. The delirium may be a sign that they're deteriorating or it may be a trigger."
It is often missed because most delirious patients don't exhibit characteristic agitation and restlessness but are quiet, albeit confused, "perfect patients", he said.
"Both sorts of delirium are associated with a range of impaired outcomes: increased hospital stay, inhibited recovery, decreased return to previous cognitive function and even a higher mortality," he said.
Those who experience delirium after surgery have also been shown to be more likely to develop dementia, Associate Professor Scott said.
While doctors don't yet know how delirium is linked to death and dementia – whether it's the chicken or the egg - researchers in US have found that shortening the duration of a delirium spell does have a positive impact on longer term affects, he said.
"We need to measure and assess delirium as part of standard hospital care," Associate Professor Scott said.
"[Delirium] is common, we know it's associated with bad outcomes, we know there are things we can do at the moment to modify or treat the condition post-operatively."
To prevent and treat delirium, doctors can use lower doses of anaesthesia, anti-psychotic medications and help orient patients, decrease their pain and avoid sedatives
Researchers at St Vincent's have been screening patients for delirium before and twice each day after surgery.
They're also given patients the drug Ketamine, commonly used as a horse tranquiliser, after surgery because they believe it could prevent delirium.
"No one knows the neuro-chemical basis for delirium, it's almost like a brain attack," Associate Professor Scott said.
Associate Professor Lis Evered, the research head of Anaesthesia and Acute Pain Medicine at St Vincent's, said the cognitive function of all patients over 65 years old should be tested before surgery.
"We don't know if people change post-operatively if we don't know how they're functioning pre-operatively," she said.
"Even having one or two of the features of delirium may put you at increase risk of cognitive impairment and increased mortality."
The journalist attended the conference as a guest of ANZCA.
