Key messages
- Delirium is an acute disturbance in a person’s attention, awareness and cognition that can be caused by an acute medical condition or medication changes. Delirium is serious and may be the only sign of a deteriorating patient.
- Delirium should be treated as a medical emergency.
- Delirium is common in older patients, yet it is often overlooked, misdiagnosed and poorly managed. This can lead to the person experiencing falls, incontinence, malnutrition, dehydration, infections and pressure injuries.
- Delirium can often be prevented and can be treated and managed. As clinicians we must listen to the families of our patients when they tell us the person seems confused. If the person does not have family or friends visiting regularly, we need to be extra vigilant to detect changes in a person’s behaviour and investigate promptly. All team members are responsible for this and should feel confident to escalate their concerns.
- In addition to following health service policy and procedures, consider the recommended actions and discuss them with colleagues and managers.
“We must recognise and respond to delirium as we would any other medical emergency…[if we don’t] the outcome is as bad for older patients as if they experienced an acute myocardial infarct” (Geriatrician, Clinical Leadership Group on Care of Older People in Hospital)
Delirium is a serious condition where the person experiences a disturbance in attention, perception, awareness and cognition. Delirium may be caused by general medical conditions (for example, infections, hypoxia), certain medications, intoxicating substances or a combination of these.
Delirium develops quickly and symptoms fluctuate throughout the day. It usually lasts for a few days but may persist for weeks or even months in vulnerable older adults1,2. Delirium may be the only sign of medical illness or a rapidly deteriorating patient.
Delirium can be hyperactive, hypoactive (‘quiet’ delirium) or mixed. Hyperactive delirium is characterised by increased motor activity, restlessness, agitation, aggression, wandering, hyper alertness, hallucinations and delusions, and inappropriate behaviour. Hypoactive delirium is characterised by reduced motor activity, lethargy, withdrawal, drowsiness and staring into space. It is the most common delirium in older people. ‘Mixed’ delirium is where people have features of hyperactive and hypoactive delirium.
Delirium symptoms develop quickly
Delirium develops quickly, over hours or days, and symptoms fluctuate throughout the day and are often worse at night.
Symptoms include:
- difficulty directing, focusing, sustaining or shifting attention
- confusion
- fluctuating or reduced consciousness
- disorientation to time and place (particularly time)
- disturbance of the sleep-wake cycle, for example, agitated or restless at night and drowsy during the day
- impaired recent memory
- speech or language disturbances, for example, rambling speech
- increased or decreased psychomotor activity
- emotional disturbances, for example, fearfulness, irritability, anger, sadness
- hallucinations and delusions
- lethargy and fatigue.
Delirium and ageing
Studies have reported that:
- older patients in surgical, palliative care and intensive care settings experience the highest rates of delirium3
- patients may come to hospital with delirium or may develop delirium while in hospital4
- patients are frequently discharged from hospital with persisting symptoms of delirium5
- delirium is preventable in 30–40 per cent of cases5.
Older people who experience delirium are at greater risk of functional and cognitive decline, falls, hospital acquired infections, pressure injuries and incontinence. Delirium can cause longer lasting cognitive impairments in patients after surgery and may ‘lead to permanent cognitive decline and dementia in some patients’3. Delirium is also associated with higher mortality and morbidity, increased length of hospital stay and admission to residential care6,7.
Risk factors for delirium
A range of factors affects an older person’s risk of developing delirium in hospital. Some factors are predisposing, that is they are related to characteristics of the person; some are precipitating, that is they are related to the person’s illness or the hospital environment. Delirium involves an interaction between the patient’s predisposing vulnerabilities, which puts them at greater risk when faced with precipitating factors.
| Predisposing factors – related to the person | Precipitating factors – related to the illness or environment |
|---|---|
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Notes:
* Comorbidity can be measured using the Charlson Comorbidity Index.
** BUN:creatinine ratio is the ratio of blood urea nitrogen (BUN) to serum creatinine and is used to determine acute kidney problems or dehydration. In Australia, it is referred to as urea:creatinine ratio.
Delirium and discharge planning
After an episode of delirium in hospital, an older person’s cognitive function and ability to manage at home or in care may be impacted. To help patients make a smooth transition from the hospital to their home or care facility, consider how the patient will manage and how their family or carer will cope, and what services and supports are required. Discharge planning should be documented, include the patient, carers and other professionals, and incorporate referrals to community health and support services where required.
Involve the patient, carers and other professionals
- Involve the older person and their family or carer in discharge planning.
- Obtain recommendations from the treating team and allied health.
- Give the person and their family and carer written information about delirium and who to contact if they have any ongoing concerns.
- If the person is socially isolated, consider what extra supports they will require and how you can address these needs.
Document the episode, patient status and medication
The discharge summary paperwork to be provided to the GP should include:
- the patient’s episode of delirium, including details of persisting symptoms
- the person’s cognitive and functional status on discharge compared with their pre-morbid status
- any changes to their medication, including the reason for the change, possible side effects or drug interactions, how long the medication should be taken, and when it needs to be reviewed and by whom
- antipsychotics should be ceased unless there is good reason for their continuation; an ongoing evaluation and a plan to cease use should be included.
Refer to community health and support services
Describe the person’s need for monitoring and support by health professionals and other services in the community.
- The person’s GP will do the monitoring and follow-up, so provide test results and reports of all key and unresolved issues, including those needing further consideration or ongoing surveillance.
- Identify additional services needed and refer to inpatient or community health and support services.
Preventing and managing delirium
There are many things we can do to help older people and their families and carers understand, prevent and manage delirium. Here are some recommendations.
Preventing and managing delirium
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