Delirium Awareness and Cognitive Impairment
Published: 31 May 2022
Published: 31 May 2022
When any person, particularly an older adult, accesses a healthcare service, there is a need for health professionals to not only treat their prioritising health concerns but also recognise and treat any other comorbidities they may have concurrently (or consequently) developed during their stay.
One such comorbidity that may occur during a hospital stay is delirium. Any patient who has had surgery, is in pain, has moved beds multiple times or is dehydrated is at risk of delirium.
However, delirium is often confused with dementia due to their many similarities, and differentiating the two conditions can be difficult in older patients.
This article will help you to differentiate between types of cognitive impairment, with a particular focus on delirium and how it can be assessed and treated.
Memory loss and confusion were once considered a normal part of ageing.
We know this is no longer the case, and older adults can remain alert and capable for as long as they live. Furthermore, while delirium is most common among older adults, it can affect people of any age (ACSQHC 2021).
If confusion and memory problems do set in, it's important to establish what the cause is so that the person can be appropriately treated.
Someone who is cognitively impaired is at a higher risk of experiencing various complications including falls, pressure injuries, functional decline, loss of independence, hospital re-admission, admission to residential aged care and even mortality (ACSQHC 2019; ACI 2015).
Despite the potential devastation it can cause, in Australian hospitals, cognitive impairment remains under-recognised and often misdiagnosed.
About 20% of people admitted to hospital over the age of 70 will have dementia and 10% will have delirium, while 8% will develop delirium while in hospital (ACSQHC 2019).
It’s also possible for a person to experience both dementia and delirium at the same time (Dementia Australia 2020).
Cognitive impairment is a term used to describe someone’s current state. It generally presents as a state of confusion; loss of memory or attentiveness; difficulty understanding or making sense; difficulty recognising people, places or things; or changes in mood (Healthdirect 2020).
Because cognitive impairment is often misdiagnosed or unidentified, it’s important to understand and differentiate between common forms of cognitive impairment and know how they can affect an individual.
There are many similarities between dementia and delirium, causing them to often be mistaken for one another. Depression can also be potentially confused with both dementia and delirium. Therefore, it’s important to perform a comprehensive assessment of the individual in order to ensure an accurate diagnosis (ACSQHC 2019).
Dementia is a progressive, chronic cognitive impairment that affects memory, judgment, language and the ability to perform everyday tasks. Delirium, on the other hand, is a treatable condition and is an acute disturbance of consciousness, attention and cognition that tends to fluctuate during the course of a day (ACSQHC 2018).
Dementia | Delirium | Depression | |
---|---|---|---|
Duration | Chronic condition that is progressive. | Lasts hours to weeks in duration. | Can last weeks to months to years. |
Onset | Chronic onset. | Acute onset. | Often abrupt onset. |
Attention | Generally normal attention. | Impaired or fluctuating attention. | Distractible but minimal impairment of attention. |
Memory | Recent and remote memory impairment. | Recent and immediate memory impairment. | Islands of intact memory. |
Alertness | Generally normal alertness. | Fluctuates between lethargic and hyper-vigilant. | Alert. |
Thought Pattern | May have word-finding difficulties and poor judgment. | Disorganised thinking with slow or accelerated thoughts. | Thinking intact but with themes of helplessness or self-depreciation. |
(Agency for Clinical Innovation 2020)
A person with delirium might:
(ACSQHC 2021)
It’s important to note that delirium has many risk factors and will result from a complex interplay between these risk factors and their health-related events occurring.
This interplay can be demonstrated in instances such as a patient who has pre-existing dementia, is taking multiple medications and also has sensory impairments, who then develops acute delirium after they are given a sedative to help them sleep (ACSQHC 2013).
Some of the risk factors for the development of delirium include:
Predisposing risk factors | Precipitating risk factors |
---|---|
|
|
(Adapted from ACI 2020b; ACSQHC 2021)
The mnemonic MISTE can be used to help remember and group possible causes of delirium:
(Caplan 2011)
Because of the under-identification of people with cognitive impairment and the potential complications it can cause, it’s important to perform a delirium risk assessment for all patients who present with any of the following:
(ACSQHC 2021)
Ensure you are familiar with the delirium assessment tool used in your organisation. Examples include the Confusion Assessment Method (CAM), CAM-intensive care unit (CAMICU), 3-minute diagnostic interview for CAMdefined delirium (3D-CAM), the Nurses Delirium Screening Checklist (NUDESC) and the 4AT (ACSQHC 2019).
Early screening can allow steps to be taken to identify the cause of cognitive impairment and determine if it is a reversible condition, such as delirium as the result of a medication side effect. Treatment can then be commenced and further potential complications avoided (NIA 2021).
Often, initial screening for cognitive impairment takes less than 10 minutes to perform. If the results are positive (i.e. cognitive impairment is present), a more detailed cognitive impairment assessment may then need to be performed. Family members and close companions can be good sources of information about the individual when performing an assessment (NIA 2021).
Management of a patient with cognitive impairment should be individualised, however, most organisations will have policies and protocols in place to guide care.
The goal of delirium management is to address its underlying cause and prevent complications such as dehydration, malnutrition, falls and pressure injuries (ACSQHC 2021).
As a general rule, antipsychotic medicines should not be used in the treatment of delirium apart from in very limited circumstances (i.e. short-term use where non-drug strategies are ineffective or there is an imminent risk of harm to the patient or another person). Antipsychotics are typically ineffective and treating the underlying causes of delirium and may cause side effects that can lead to serious harm such as falls, pneumonia and even death (ACSQHC 2021).
Instead, non-medication strategies are recommended. These can include:
(ACSQHC 2019)
There are a variety of interventions that should be used together to reduce the risk of delirium. These include:
(ACSQHC 2021)
It’s important to remember that while a person with a new or existing cognitive impairment is in hospital, they are not only dealing with their health condition but also a busy, noisy and unfamiliar environment. This can cause a considerable amount of distress and also exacerbate disorientation, further decreasing the person’s independence and functional ability (ACSQHC 2013).
Note that people who have experienced delirium in the past are at higher risk of developing delirium again in the future (ACI 2020b).
For more information on recognising, managing and preventing delirium, see the ACSQHC Delirium Clinical Care Standard.
Question 1 of 3
Which one of the following is more likely to cause fluctuating symptoms?