Delirium in 30

Learn the essentials of delirium care in 30 minutes

About 30 minutesFor adult health and care staff and students
A nurse sits beside an older man in a hospital bed and holds his hand while he talks. He has oxygen tubing in his nose.

For staff at every stage of training, new to delirium or wanting a quick refresher.

This 30-minute course focuses on adult care in general wards, emergency departments and care homes.

This is a general course. Professionals and other healthcare staff have different roles in delirium management. Work within your role and local care arrangements.

Take longer if you need to; you can pause and return.

New to health or care work?

Start with the eight-minute introduction to the words and ideas used here, then return to Delirium in 30.

What you should be able to do afterwards
  • Recognise a new change, including drowsiness and withdrawal.
  • Establish what is usual and report the time course.
  • Explain how a structured assessment supports clinical diagnosis.
  • Seek appropriate help and describe information needed to look for causes.
  • Provide appropriate everyday care and respond to distress.
  • Record, hand over and explain the plan for review and recovery.
Settings that need additional teaching

Children, intensive care, the immediate recovery room after surgery, alcohol or drug withdrawal and intoxication, and end-of-life care require relevant specialist guidance. This shared introduction does not replace that teaching.

New to healthcare? Words used in this course
Acute
Developing over a short time, often hours or days.
Attention
The ability to focus and remain involved in a conversation or task.
Fluctuation
A change that varies over time, for example being more alert in the morning and more drowsy later.
Baseline
The person’s usual mental and everyday abilities before the new change.
Dementia
A condition in which long-term changes in thinking affect everyday life. A person with dementia can also develop delirium.
Observations
Measurements such as breathing rate, pulse, blood pressure, temperature and oxygen level.
Escalate
Ask the appropriate person or service for more urgent or senior help.
De-escalation
Words and actions intended to reduce distress or a risk of harm.
Non-pharmacological care
Care that does not involve giving a medicine, such as reassurance or help with hearing aids.

No account is required. It works on a phone.

Full reading view
An older woman lying in a hospital bed with her eyes closed and nasal oxygen in place.
A person who becomes quieter and sleepier than usual needs assessment as much as a person who is agitated.

Notice the change

Mrs Morgan, 84, has dementia and was admitted after a fall. She usually chats, eats independently and walks with a frame.

On her second day in hospital, she is much less talkative. She is sleepy at times, responds slowly, eats little and needs more help to stand. Her daughter says the change began yesterday. At some points she seems more like herself.

These changes need prompt assessment. A person who becomes drowsy and withdrawn may have delirium, even if they are neither agitated nor complaining of confusion.

What delirium means

Delirium is a sudden change in mental functioning. The person has difficulty paying attention and thinking clearly. Their alertness or behaviour may change. Some see or hear things that others do not. Delirium develops over hours or days, usually during illness, after an operation or because of medicines or other physical problems. Symptoms may vary during the day.

Diagram of signs of delirium, described in the text version below.
Signs of delirium. Not everyone has all of these changes.
Text version of the diagram

Delirium is a sudden change from the person’s usual state. Features include difficulty paying attention, altered alertness, false beliefs, hallucinations and changes that fluctuate. Not everyone has all of these changes.

A note on terminology

Delirium has historically been called by many names, including “acute confusion”, and is sometimes described informally as “not themselves”. Use “delirium” as the clinical term. Do not use “acute confusion” or other terms in place of “delirium”. Consistent terminology helps teams communicate and gives patients and families accurate information.

The person may struggle to understand where they are or what staff are doing. Ordinary care can feel frightening. Delirium needs prompt assessment and treatment, together with care that helps the person feel safe.

Anyone who spends time with the person may notice the change first. You do not need to be able to diagnose delirium before asking for help.

What causes delirium? Delirium occurs when illness, an operation, medicines or other physical problems disturb brain function. Common triggers include infection, low oxygen, pain and dehydration. More than one trigger is often present.

Who is at higher risk of delirium? Anyone can develop delirium. The risk is higher in older people, and in people who are frail, have dementia or have had delirium before.

How common is delirium? Delirium is common. About one in four adults on medical wards has it at some point during the admission. It is also a sign of serious illness: people who have had delirium are about twice as likely to die in the following two years as similar people who have not, and more likely to move into a care home or to develop dementia later. Finding it early and treating the causes gives the person the best chance.

Report the change now

Tell the nurse responsible for the person or the senior member of staff. For example: “Mrs Morgan is much sleepier than usual and is eating very little. Her daughter says this began yesterday. Please arrange assessment now.”

If the person is very difficult to wake, has severe breathing problems, has new weakness on one side or new difficulty speaking, has a new change after a fall or head injury, or is rapidly getting worse, use your setting’s emergency response.

Which feature makes Mrs Morgan’s change concerning?

Sources: NICE CG103; Gibb and colleagues (2020); Witlox and colleagues (2010); Delirium terminology consensus (2020)

Recognise different presentations

Delirium has several possible appearances. Compare what you see with the person’s usual state and ask how quickly it changed.

An older man resting in a hospital bed with his eyes closed and an oxygen mask in place.

Drowsy or withdrawn

The person may speak less, respond slowly, lose track of a conversation, move less or stop eating and drinking as usual. This is often called hypoactive delirium. This is the most common form of delirium in older people in hospital, and the form most often missed. Drowsiness and withdrawal can be less noticeable than agitation.

An older woman in a hospital bed with both hands over her face.

Restless or agitated

The person may be unable to settle, pull at bedding or try to leave. This is often called hyperactive delirium. Some people have both patterns at different times.

Watch for reduced engagement

Describe the man’s actions and response. Consider what information is still needed about his usual state and when the change began.

Text alternative

An older man holds a spoon above a bowl but does not eat. A nurse asks whether he will try some soup. He responds slowly. The scene illustrates reduced engagement. It does not establish a diagnosis or swallowing safety. Check alertness and the individual swallowing plan before oral intake.

In this scene, the man engages little with the meal and the staff member’s question. In practice, seek information about whether this is new and assess for illness or other causes. Reduced responsiveness may also require emergency assessment.

Some people with delirium see or hear things that others do not. These experiences are called hallucinations. Some develop frightening beliefs, such as believing staff intend to harm them. Neither agitation nor hallucinations are required for delirium. Their absence should not reassure you when someone has a new change.

Delirium and dementia: useful distinctions
FeatureDeliriumDementia
Usual onsetHours or daysUsually months or years
Attention and alertnessOften change; may vary during the dayDepend on type and stage; compare with the person’s usual state
A sudden deteriorationNeeds prompt assessmentAssess for delirium or another acute problem
Course within a dayVaries from hour to hourUsually stable day to day (dementia with Lewy bodies also fluctuates)

Delirium and dementia often occur together. If it is difficult to distinguish them, assess and manage possible delirium promptly. A more settled hour does not exclude it.

Sources: NICE CG103; Morandi and colleagues (2017); Inouye and colleagues (2001)

Find out what is usual and assess

Baseline means the person’s usual abilities and behaviour before this change. Ask the person where possible. Family, carers, familiar staff and records can help you establish what is usual, when the change began and whether it has varied.

An older man sitting beside his wife's hospital bed, talking with her.
Someone who knows the person can describe what is usual and when it changed.

Ask someone who knows the person

After his wife’s operation, Mr Dawson says she has become suspicious and struggles to follow conversation. Staff ask how she was before admission. He describes her usual memory, conversation and daily activities, then explains when the new change began.

Consider: What information about her usual state and the time of change would you record? A new problem after an operation should prompt clinical assessment.

Example questions to establish the history

What is the person usually like? What has changed, and when did it begin? Has the change varied during the day?

Use a structured assessment appropriately

The 4AT is a brief assessment used to help detect possible delirium and cognitive impairment. Cognitive impairment means difficulty with mental abilities such as attention or memory. The final diagnosis requires clinical assessment.

Different units across the world use different tools. This section covers the 4AT; refer to local instructions if you use a different tool. Staff who administer it need to be competent to use and interpret it. If this is outside your role, report the change and ask for assessment. Urgent care should proceed while the team assesses delirium.

The 4AT has four parts:

  1. Alertness.
  2. Four questions: age, date of birth, place and year.
  3. Attention, tested with Months Backwards.
  4. A recent change in mental functioning, or variation in that change.
The 4AT at a glanceFour items add to a total, followed by interpretation bands in ascending score order.1. Alertness0 or 42. Four questionsage, date ofbirth, place, year0, 1 or 23. Attentionmonths backwardsfrom December0, 1 or 24. Acute changeor fluctuatingcourse0 or 4Total0delirium or severe cognitive impairment unlikely(but delirium still possible if item 4 information incomplete)1 to 3possible cognitive impairment4 or abovelikely delirium +/- cognitive impairment
  1. AlertnessScore: 0 or 4
  2. Four questions: age, date of birth, place, yearScore: 0, 1 or 2
  3. Attention: months backwards from DecemberScore: 0, 1 or 2
  4. Acute change or fluctuating courseScore: 0 or 4

Total

0
delirium or severe cognitive impairment unlikely (but delirium still possible if item 4 information incomplete)
1 to 3
possible cognitive impairment
4 or above
likely delirium +/- cognitive impairment
The four items and what the total suggests. Follow the official instructions for scoring.
Text version

Alertness scores 0 or 4. Four questions, age, date of birth, place and year, score 0, 1 or 2. Attention, months backwards from December, scores 0, 1 or 2. Acute change or fluctuating course scores 0 or 4. A total of 4 or above suggests likely delirium +/- cognitive impairment. A total of 1 to 3 suggests possible cognitive impairment. A total of 0 means delirium or severe cognitive impairment unlikely, but delirium is still possible if item 4 information is incomplete.

Official 4AT user guide

The months backwards task

Use the official 4AT instructions to ask the person to name the months backwards, starting at December. Score the response using those instructions. This is one part of the assessment; the other items and the history remain necessary.

Open the official 4AT user guide

A worked example

Mrs Dawson, after her operation. She is alert (Alertness 0). She gets her age and the place right and the year and her date of birth wrong (Four questions 2). Months backwards: she reaches August and stops (Attention 1). Her husband describes a clear change over the past two days (Change 4). Total 7: likely delirium. The team arranges clinical assessment and looks for causes.

An illustrated 4AT case

An illustrated 4AT assessment of Mr Reid after bowel surgery, scoring 11 out of 12. The case and scores are described below.
Example case: Mr Reid is agitated the day after bowel surgery. His 4AT score is 11/12: 4 + 2 + 1 + 4. Likely delirium; confirm clinically.
Read the case and scores

Mr Reid is restless, pulls at his drip and tries to get out of bed the day after bowel surgery.

  1. Alertness: 4. He is markedly agitated.
  2. Four questions: 2. He makes two or more errors.
  3. Attention: 1. He refuses to start the Months Backwards task.
  4. Acute change or fluctuating course: 4. His son reports that he was calm yesterday and that this behaviour is new.

Total: 11/12. The result indicates likely delirium. Confirm clinically and look for causes.

For more practice, see the set of illustrated 4AT cases.

Interpreting a 4AT total
ScoreInterpretation
0Suggests no delirium and no moderate-to-severe cognitive impairment. Neither is definitively excluded.
1–3Suggests possible cognitive impairment. Interpret with the history and clinical findings.
4–12Suggests likely delirium, with or without cognitive impairment. Arrange clinical diagnostic assessment.

Help the person hear and understand. Check hearing aids and glasses, use an interpreter when needed, and account for difficulties speaking or understanding language. A communication barrier needs attention before you interpret performance.

Scoring when the person is unable to attempt a task

The 4AT provides scores for someone unable to attempt the cognitive items because of illness, drowsiness or severe inattention. Follow the official guide; do not abandon the assessment. The guide also explains interpretation in severe dementia.

Which tool in critical care?

NICE recommends CAM-ICU or ICDSC in critical care and the recovery room immediately after surgery. Use the relevant specialist pathway in these settings.

A 4AT score of 0 was recorded. A relative then reports a marked mental change that began yesterday and is still present. What should happen?

Sources: Official 4AT user guide; NICE CG103

A nurse placing a pulse oximeter on an older man's finger at the bedside.
Observations belong in the report: breathing rate, pulse, blood pressure, temperature and oxygen level.

Act promptly and look for causes

A new mental change needs urgent clinical assessment. Tell the responsible nurse or clinician and confirm when assessment will happen. In a care home, use the urgent medical assessment route. Do not wait for a routine visit.

In a care home

Mr Singh, 88, lives in a care home. This morning he did not get up for breakfast, which he never misses, and the carer could not hold his attention. The senior carer phones the practice using the home's urgent route and says what has changed and when. She does not wait for the routine weekly visit.

Do not delay urgent care to finish a delirium test

Start emergency assessment and treatment immediately when needed. The team can assess delirium alongside this care.

Check the person’s immediate condition within your role. Trained staff follow their emergency assessment procedure, including checks for low blood glucose. Report the mental change and abnormal observations, such as breathing rate, pulse, blood pressure, temperature or oxygen level.

Several problems may contribute

The clinician looks for causes and treats them. Examples include infection, low oxygen or blood glucose, a head injury after a fall, pain, dehydration, constipation and difficulty emptying the bladder. Medicines are a frequent cause: newly started or increased opioids, medicines with anticholinergic effects (for example oxybutynin or amitriptyline), benzodiazepines and sleeping tablets, and sudden stopping of alcohol or benzodiazepines. Several causes may occur together.

Several causes at onceNine possible causes surround the statement that delirium often has more than one acute trigger.InfectionLow oxygenLow bloodglucoseMedicinesPainDehydrationConstipationDifficultyemptying thebladderHead injuryafter a fallDelirium oftenhas more thanone acutetrigger.

Delirium often has more than one acute trigger.

  • Infection
  • Low oxygen
  • Low blood glucose
  • Medicines (new or increased opioids, anticholinergic medicines, benzodiazepines, sleeping tablets; sudden stopping of alcohol or benzodiazepines)
  • Pain
  • Dehydration
  • Constipation
  • Difficulty emptying the bladder
  • Head injury after a fall
The clinician looks for all of these, because several are usually present together.
Text version

Possible causes are infection, low oxygen, low blood glucose, medicines, pain, dehydration, constipation, difficulty emptying the bladder and head injury after a fall. Medicines include newly started or increased opioids, medicines with anticholinergic effects, benzodiazepines and sleeping tablets, and sudden stopping of alcohol or benzodiazepines. Several causes may occur together.

Share changes in medicines, alcohol use, intake, urine, bowel movements, sleep and mobility, and any recent fall. Describe pain or distress, including facial expression when speech is difficult; an observational pain scale such as the Abbey Pain Scale or PAINAD can be used where your setting has adopted one. Confusion alone does not establish a urinary infection, and neither does a positive urine dipstick in an older person.

Return to Mrs Morgan

Her nurse finds fever and a new low oxygen level and seeks urgent medical review. The team assesses possible causes and begins treatment.

The pharmacist reviews medicines. Therapy staff assess her movement and everyday abilities. Her daughter provides the history and brings her hearing aids.

Notice, report, assess, care, reviewFive steps joined by arrows. Anyone notices, reports and provides care. Clinicians assess and review. Review returns to assessment.NoticeA new changefrom usualReportTell theresponsiblenurse orclinician; usethe emergencyresponse ifneededAssessHistory,observations,structuredassessment,causesCareMeet physicalneeds, reducedistress, keepthe personsafeReviewCheck theresponse;agree whoreviews nextand whenReview returns to assessmentAnyoneClinician
  1. AnyoneNoticeA new change from usual
  2. AnyoneReportTell the responsible nurse or clinician; use the emergency response if needed
  3. ClinicianAssessHistory, observations, structured assessment, causes
  4. AnyoneCareMeet physical needs, reduce distress, keep the person safe
  5. ClinicianReviewCheck the response; agree who reviews next and when

Review returns to assessment.

The steps proceed together, and review returns to assessment.
Text version

Anyone can notice a new change from usual, report it to the responsible nurse or clinician and use the emergency response if needed, then provide appropriate help and check that the concern was received. A clinician assesses the history, observations, structured assessment and causes. Anyone helps meet physical needs, reduce distress and keep the person safe. A clinician reviews the response and agrees who reviews next and when. Review returns to assessment.

Everyone can notice, report, offer appropriate help and check that a concern has been received. Clinical assessment, investigations and prescribing depend on professional responsibilities and competence.

After you report a new change, no review has happened and the person is getting worse. What should you do?

Sources: NICE CG103; NHS: sudden confusion

A nurse seated at eye level beside an older man in a hospital bed; a framed family photograph stands on the bedside cabinet.
Approach within view, at eye level, and explain before you touch.

Help the person feel safe

A person with delirium may misunderstand their surroundings or an attempt to help. They may feel frightened while still and saying little. Ask how they feel. Watch for discomfort if speech is limited.

Approach within their view and introduce yourself. Check they can hear you. Speak calmly, give one short explanation at a time and allow a response. Explain before touching or beginning care.

An example of reassurance

“You are in hospital. I’m one of the nurses. You have been unwell, and it has made it harder to think clearly. I’ll explain what we are doing.”

Use words that fit what you know and can offer. If you promise to return, do so.

Acknowledge fear without agreeing that a threat is real. Avoid arguing or repeatedly testing memory. Ask what usually reassures the person. Involve someone familiar if the patient welcomes this.

Check for pain, thirst, hunger, a full bladder, constipation, noise and an uncomfortable position. Help the person use glasses or hearing aids. If there is an immediate risk of harm, get help and use the least restrictive safe approach under local guidance.

Delirium can affect a person's ability to understand and weigh a particular decision. Capacity is decision specific and is assessed by the clinician under the law that applies where you work. The person's wishes and the views of those who know them still count, and care continues in the person's best interests.

Medication has a limited role

There is no drug treatment for delirium itself. Never prescribe an antipsychotic or benzodiazepine simply because a person has delirium. Consider these medicines only for intractable distress or significant safety risks that have not responded to non-drug measures.

Only a clinician authorised to prescribe should decide whether a medicine is appropriate. The prescriber checks individual risks, uses the lowest appropriate dose for the shortest possible time (a day or two, not weeks or months), and records monitoring, review and stopping plans. Stop the medicine before discharge unless a senior decision maker has explicitly authorised continuation. Follow current prescribing guidance.

If an antipsychotic or other psychotropic drug is being considered, check contraindications and cautions carefully. For example, antipsychotics can have severe adverse effects in Parkinson’s disease and dementia with Lewy bodies.

Care and treatment of causes continue.

Report distress or risk, what was tried and the response. Assess distress separately from movement or noise.

Which is the most useful response to a frightened person who believes staff will hurt them?

Sources: MHRA haloperidol advice; NICE CG103

A survivor’s account

Listen to what Dr S says about staff spending time with a person who has delirium.

Think Delirium · Delirium survivor Dr S · 1 minute 59 seconds. Loading the player connects to YouTube.

Watch on YouTube

Written alternative

Dr S describes the value of staff spending time with someone who has delirium. Listening to the person’s experience is part of care throughout the illness. Consider what you could ask before beginning a procedure.

A care worker supporting a person’s forearm beside a walking frame.
Movement, meals, drinks, glasses, hearing aids and sleep: several ordinary things together reduce delirium.

Delirium prevention and everyday care

People are more vulnerable to delirium when they are older, have dementia or another cognitive impairment, have a hip fracture or are severely ill. Support should begin before delirium develops.

Several measures together reduce the risk of delirium in hospital by roughly 40 per cent in trials (moderate certainty). Choose measures for the person’s needs and review whether staff have been able to provide them. The same everyday needs require attention during delirium.

Food, fluid and comfort

Offer appropriate help with meals and drinks. Follow swallowing advice and any fluid restriction. Check pain, bowel and bladder needs. Report reduced intake or difficulty swallowing.

Hearing and vision

Help the person use their glasses and hearing aids. Check that the aids work and are within reach. Adapt communication to their needs.

Movement and sleep

Support movement and mobility appropriate to the person’s condition, with the assistance and equipment they need. Reduce avoidable interruptions at night while continuing necessary observations and treatment.

Familiar contact and medicines

Offer explanation, familiar contact and orientation. Avoid unnecessary moves. Ask for medicines to be reviewed by a qualified clinician or pharmacist.

A drink, a walk or a hearing aid alone does not guarantee prevention. The team needs to address the relevant problems together. A person may develop delirium despite appropriate care.

Mrs Morgan is drowsy and has hardly drunk today. What is the safest next action?

Sources: NICE CG103; Burton and colleagues, Cochrane review (2021)

An older man standing beside a window at home, with one hand on a walking stick.
Recovery may continue after discharge. Explain what to expect and who to contact if problems persist.

Explain, record and support recovery

Explain delirium to the person and family using plain words. Describe what has changed, what the team is treating and how the person is being supported. Invite questions and reports of further changes.

Many people improve as the causes are treated. Recovery varies: some people have symptoms for weeks or months and need continuing support. A new deterioration still needs prompt assessment. Do not assume that it is an expected part of recovery.

During recovery, offer an opportunity to talk about frightening experiences. Discuss any continuing difficulty with thinking, sleep, movement or everyday activities. Persistent symptoms need clinical review, further assessment of possible causes and a follow-up plan.

Record enough for the next person to act

Record the usual baseline and its source; the new changes and when they began; observations and assessment results; who was informed and when; actions and response; and who will review the person next and when.

At transfer or discharge, record a confirmed delirium diagnosis, its course, remaining difficulties, treatment changes and follow-up. Hand over review and stopping plans for medicines started for delirium-related distress. Explain the plan to the person and those supporting them. Give a named contact or service for concerns and clear advice about urgent help.

Family information is available at Delirium Support. This includes downloadable resources that can be printed and given to families. Offer it alongside a conversation and the person’s care plan.

Sources: NICE CG103; Academy: persistent delirium

Check your understanding

Answer all 10 questions, then read the explanations. You can review the relevant teaching and try again. For a completion certificate, score at least 8 out of 10 and answer both urgent-action questions (2 and 10) correctly. Review and correct any missed urgent-action answer.

This is a formative check of understanding.

1. A person with dementia becomes drowsy, withdrawn and less able to follow a conversation over one day. What is the best interpretation?

Answer: This needs assessment for possible delirium. A sudden change from usual needs assessment. Hypoactive delirium may cause drowsiness, reduced activity and poor attention. Dementia increases vulnerability.

2. A person is very difficult to wake and is breathing abnormally. What should happen first?

Answer: Use the emergency response and begin assessment within your role. Urgent assessment and treatment take priority. A delirium tool must not delay emergency care.

3. Which information is most useful when establishing baseline?

Answer: How they usually think, communicate and function, and when this changed. Ask the person and people who know them, and use records. Establish both the usual state and the time course of the change.

4. What does a 4AT score of 4 or more mean?

Answer: Likely delirium - confirm clinically. A score of 4 or more suggests delirium. Confirm clinically using the history, examination and wider information.

5. After a 4AT score of 0 is recorded, a relative reports a marked mental change beginning yesterday and still present today. What is appropriate?

Answer: Assess the concern and review the clinical findings. The new history meets Item 4, which scores 4. Review the recorded total and arrange clinical assessment. Pass the history to the clinician if assessment is outside your role.

6. Which response to distress is most appropriate initially?

Answer: Check physical needs, explain calmly and offer reassurance. Look for pain, discomfort and other causes. Help the person feel safer. Medication decisions require an authorised prescriber and an individual assessment.

7. Which plan best reflects delirium prevention?

Answer: Choose several measures for the person’s food, fluid, movement, sensory and sleep needs. Prevention uses several measures together, adapted to the person and setting. Continue necessary monitoring and follow swallowing, fluid and mobility advice.

8. Which statement about causes is most accurate?

Answer: Several contributors may coexist and need assessment. Look for acute illness and other contributors, such as medicine effects, pain, dehydration, constipation and urinary retention.

9. What is the most useful handover?

Answer: Usually alert; new drowsiness today; findings and actions recorded; urgent review agreed. The next team needs enough information to understand the change and act. Record who has been informed and who will review the person and when.

10. Someone recovering from delirium becomes suddenly much worse. What should the family or staff do?

Answer: Seek prompt clinical assessment and emergency help if seriously unwell. Recovery can vary, but a new deterioration needs assessment. Give families clear contact details and urgent-help advice.

Open the printable practice card

Further learning after this course

After this foundation, choose the topic you need: safety, distress and agitation, finding causes, distress, persistent delirium, communication, or 4AT practice.