This information is helpful for those who:
- are at risk of delirium
- have experienced delirium
- care for someone who has delirium.
What is delirium?
Delirium is a change in a person’s mental state or consciousness. Someone with delirium may be confused, have difficulties with understanding and memory or may show personality changes. It is acute in onset, developing over hours or days and is usually temporary.
There are different types of delirium:
- hyperactive (agitated and restless)
- hypoactive (drowsy and withdrawn)
- mixed delirium (hyperactive and hypoactive states come and go).
How common is delirium?
Delirium is very common and often occurs in patients in hospital with other problems.
Some people may have delirium when they are first admitted to hospital or when they go into long-term care or it may develop during their stay.
It is most frequent in those who are 65 or older who:
- have difficulties with memory or understanding
- have dementia
- have a broken hip
- are seriously ill.
According to the national clinical guideline organisation the Scottish Intercollegiate Guidelines Network (SIGN) delirium is amongst the most common of medical emergencies.
Symptoms of delirium include:
- rambling speech
- difficulties following instructions
- increasing agitation or restlessness, sometimes leading to aggression
- belief people are trying to harm them
- not wanting to eat or drink
- changes to alertness
- personality changes, including paranoia.
Sometimes symptoms are worse in the evenings or overnight causing the individual to be awake at night and sleepy in the day.
Symptoms can improve within a few hours or days, but for some they may last longer. One in five people with delirium will experience symptoms which last for weeks or months.
How people experience delirium
If you are experiencing an episode of delirium you may:
- be less aware of what is going on around you
- be unsure about where you are or what you are doing there
- be unable to follow a conversation or to speak clearly
- have vivid dreams, which are often frightening and may carry on when you wake up
- see or hear people or things which aren’t there
- worry that other people are trying to harm you
- become very agitated or restless
- feel very slow or sleepy
- sleep during the day but wake up at night
- have moods that change quickly
- be frightened, anxious, depressed or irritable
- be more confused than usual, particularly at night
- feel upset towards your family for not taking you home.
The following videos gives an overview of what it can be like to have delirium:
Several factors increase the risk of delirium…
- more than one health condition or illness
- living with dementia
- hearing or visual impairments
- previous episodes of delirium.
Lifestyle: alcohol misuse.
The following factors could trigger an episode of delirium:
- surgery or injury
- illness of the brain, such as stroke or head injury
- terminal illness
- infection or sepsis
- medications such as painkillers or sedatives
- medications being discontinued or new medications being commenced
- alcohol and/or drug withdrawal.
Diagnosis / identification
It is important to identify delirium as soon as possible. Relatives and carers can provide helpful information to medical staff to help them spot if someone is experiencing an episode of delirium, for example, if they notice anything about the patient’s behaviour that is different to usual.
Where delirium is suspected there are various tests which can be used by healthcare professionals to support diagnosis:
- CAM (Confusion Assessment Method)
These tests may include asking patients questions to check for alertness, using approved checklists or undertaking observations.
These tests or checks may be completed more than once as delirium can develop at any time during a person’s illness.
If tests show that delirium is likely, a full assessment will be completed by a healthcare professional competent to identify this illness.
The diagnosis should be recorded in the patient’s notes so that others involved in their care are aware of this. Patients and their family or carers should also be informed of the diagnosis.
Further tests may be needed to find out what is causing the delirium so that this can be addressed and the root cause of the delirium stopped.
Delirium is preventable and there are measures that can be taken to reduce the risk of people developing this. This is particularly important for those staying in hospital or long term care. Measures may include:
- making sure the person is wearing glasses or hearing aids if these are needed
- explaining to the person where they are and arranging for them to having familiar items e.g. photos with them
- helping the person to sleep, for example by reducing noise and light
- helping the person to sit up, get out of bed or get moving as soon as they can
- keeping pain under control
- encouraging the person to drink and eat regularly
- checking that the person is going to the toilet regularly.
If the person is a heavy smoker, drinker or regularly uses sleeping pills or sedatives, please let staff know. Sometimes withdrawal from these drugs can worsen delirium.
Those having surgery, and their family should be told about the risk of developing delirium as this can help you cope if it happens.
If you are at risk of developing delirium, an experienced healthcare professional should check your medicines to see if anything you take may increase the risk.
An ‘All about me’ booklet or something similar can help healthcare staff taking care of the individual.
Treatment for delirium varies and may include:
- treating the underlying causes of delirium e.g. Infections, constipation/difficulties with urination or dehydration
- managing medications for other conditions and treating any side effects caused by these
- making changes to the environment to help people to feel more settled and to get sleep
- making sure people’s physical needs are met, for example that they are getting enough to eat and drink.
There is not enough evidence to show whether medicines are useful to treat delirium. In some cases however calming or sedating drugs may be required, especially if the person remains extremely distressed or could hurt themselves or the people looking after them because of their delirium.
Having family members and carers around is likely to be very reassuring and helpful in the treatment of delirium. Familiar items such as photos of loved ones or other comforting objects are also a good idea and can help with reminiscing about the past. Radio or television can also be helpful for this.
Stimulating activities during the day can help people to rest during evening, and if they are well enough, a short supervised trip out of the ward environment may be agreed.
Delirium is distressing but usually once the underlying causes have been managed, symptoms will improve.
Some people will slowly get better with time and just being at home can allow a quicker recovery.
We encourage people who have suffered from delirium and their relatives to talk openly about their experiences. This helps to fill in the blanks and make sense of what has happened which may help speed up their recovery.
Whilst some people will return to how they were before the episode of delirium, others may experience longer term problems. They may be:
- a little more confused
- less able than usual to carry out their daily tasks
- have unpleasant memories of their experiences.
We will discuss with you and your relatives or carers whether extra support is needed when you return to your home or care setting. We will make sure this is in place before you leave hospital. Support may include rehabilitation to improve, restore and maintain everyday skills and mobility.
A discharge letter will be sent to your GP. It will tell them about your delirium and say that you need an appointment so you can be reviewed by your GP or the wider primary health care team. If you have concerns please speak to staff at your appointment.
We will gather information from you and your relatives or carers whilst you are in hospital to establish if there has been a decline in your cognitive ability. If so you may be offered an appointment at a delirium clinic or with a community based memory service.
Your GP will monitor your recovery and may repeat delirium tests. If appropriate, they may refer you for further memory tests.
What if I get delirium again?
Having an episode of delirium, increases your risk of experiencing this again in the future. The hospital will make a note on your medical records that you have had delirium. This will help them decide what treatment to give you if you return to hospital for delirium or another condition.
Useful sources of information
Royal College of Psychiatrists
Health and Social Care: Public Health Agency
Tel. 0800 888 6678
Tel: 0300 222 1122
Tel. 0800 678 1602
Tel. 020 7378 4999
Health Education England: Minded for Families
L1105, V1, 24/06/2020 (Archive: 24/06/2023)