Intended for healthcare professionals

Practice Guidelines

Diagnosis, prevention, and management of delirium: summary of NICE guidance

BMJ 2010; 341 doi: (Published 28 July 2010) Cite this as: BMJ 2010;341:c3704
  1. John Young, honorary consultant geriatrician1,
  2. Lakshmi Murthy, research fellow2,
  3. Maggie Westby, clinical effectiveness lead2,
  4. Anayo Akunne, health economist2,
  5. Rachel O’Mahony, senior research fellow2
  6. on behalf of the Guideline Development Group
  1. 1Bradford Institute for Health Research, Bradford Royal Infirmary, Bradford
  2. 2National Clinical Guideline Centre, Royal College of Physicians, London
  1. Correspondence to: J Young john.young{at}

    Delirium is a complex clinical syndrome characterised by disturbed consciousness, cognitive function, or perception. Sometimes known as acute confusional state, delirium has an acute onset, a fluctuating course, and is associated with serious adverse outcomes such as death, dementia, and the need for long term care.1 Although common in general hospitals (affecting as many as about 30% of inpatients)1 and care homes, delirium is often poorly recognised1; however, it can be prevented in about one third of patients at risk.1 This article summarises the most recent recommendations from the National Institute for Health and Clinical Excellence (NICE) guideline on how to recognise, prevent, and treat delirium.2


    NICE recommendations are based on systematic reviews of best available evidence and explicit consideration of cost effectiveness. When minimal evidence is available, recommendations are based on the experience of the Guideline Development Group and their opinion of what constitutes good practice. Evidence levels for the recommendations are given in italic in square brackets.

    Assessment of risk factors

    • When people first present to hospital or long term care, assess them for the presence of the following risk factors for delirium:

      • -Age 65 years or older

      • -Cognitive impairment (past or present), dementia, or both.3 If cognitive impairment is suspected, confirm it using a standardised and validated cognitive impairment measure, such as the mini mental state examination3

      • -Current hip fracture

      • -Severe illness (that is, a clinical condition that is deteriorating or at risk of deterioration).4

    [Based on moderate and low quality evidence from prospective cohort studies]

    • Observe people admitted to hospital or long term care at every opportunity for any changes in the risk factors for delirium. [Based on the experience and opinion of the Guideline Development Group (GDG)]

    Interventions to prevent delirium

    • Ensure that people at risk of delirium are cared for by a team of healthcare professionals who are familiar to the person at risk (that is, do not change staff excessively during the person’s stay in hospital or long term care).

    • Avoid moving people within and between wards or rooms unless absolutely necessary.

    [Both the above recommendations are based on low quality evidence from a prospective cohort study and the experience and opinion of the GDG]

    • Within 24 hours of admission, assess people at risk for the following clinical factors that might precipitate delirium:

      • -Cognitive impairment, disorientation, or both

      • -Dehydration, constipation, or both

      • -Hypoxia

      • -Immobility or limited mobility

      • -Infection

      • -Multiple medications

      • -Pain

      • -Poor nutrition

      • -Sensory impairment

      • -Sleep disturbance.

    The clinical factors identified at assessment can be addressed by multicomponent interventions tailored to the person’s individual needs and care setting (table). This package of assessment and multicomponent intervention should be delivered by a multidisciplinary team trained and competent in delirium prevention. [Based on moderate and low quality evidence from randomised trials, low quality evidence from non-randomised intervention studies, indirect moderate quality evidence from a prognostic cohort study, and the experience and opinion of the GDG]

    Preventing delirium in a person at risk by addressing clinical factors identified at assessment

    View this table:

    Indicators of delirium

    Assess for recent (within hours or days) changes or fluctuations in behaviour. Assessment should be done at presentation for all people at risk and, subsequently, at least daily for all people admitted to hospital or long term care. These behaviour changes may be reported by the person at risk, or by a carer or relative, and may affect:

    • Cognitive function—for example, worsened concentration*; slow responses*; confusion

    • Perception—for example, visual or auditory hallucinations

    • Physical function—for example, reduced mobility*; reduced movement;* restlessness; agitation; changes in appetite*; sleep disturbance

    • Social behaviour—for example, lack of cooperation with reasonable requests; withdrawal*; or alterations in communication, mood, or attitude.

    Be particularly vigilant for behaviour changes that suggest hypoactive delirium (marked *). [Based on the experience and opinion of the GDG]

    Diagnosis (by specialist clinical assessment)

    • If indicators of delirium are identified, carry out a clinical assessment based on the criteria in the Diagnostic and Statistical Manual of Mental Disorders, fourth edition,5 or the short confusion assessment method (CAM)6 to confirm the diagnosis. In critical care or in the recovery room after surgery, the confusion assessment method for the intensive care unit (CAM-ICU)7 should be used. [Based on low to high quality evidence from studies of diagnostic test accuracy and the experience and opinion of the GDG]

    • A healthcare professional who is trained and competent in the diagnosis of delirium should carry out the assessment. If distinguishing between the diagnoses of delirium, dementia, and delirium superimposed on dementia proves difficult, treat for delirium first. [Based on the experience and opinion of the GDG]

    • Ensure that the diagnosis of delirium is documented both in the person’s hospital record and in his or her primary care record. [Based on moderate and high quality evidence from prospective cohort studies and cross sectional studies]

    Initial management of people with delirium

    • Identify and manage the possible underlying cause(s). [Based on moderate and low quality evidence from randomised and non-randomised studies and the experience and opinion of the GDG]

    • Ensure effective communication and reorientation (for example, explain where the person is, who they are, and what your role is) and provide reassurance. Consider involving family, friends, and carers to help with this. [Based on evidence from a low quality prospective cohort study, qualitative studies, and the experience and opinion of the GDG]

    • Provide a suitable care environment. (Please refer to the first two points in the section entitled “Interventions to prevent delirium.”) [Based on evidence from a low quality prospective cohort study and the experience and opinion of the GDG]

    Distressed people

    • If a person with delirium is distressed or considered a risk to themselves or others, use verbal and non-verbal de-escalation techniques.8 If these are ineffective or inappropriate, consider giving short term (usually one week or less) haloperidol or olanzapine. Start at the lowest clinically appropriate dose and titrate cautiously according to symptoms. [Based on low quality evidence from a randomised trial and the experience and opinion of the GDG]

    • Use antipsychotic drugs with caution or not at all for people with conditions such as Parkinson’s disease9 10 or dementia with Lewy bodies3 because such treatment increases the risk of harms such as increased extrapyramidal symptoms and the neuroleptic malignant syndrome. [Based on the experience and opinion of the GDG]

    Overcoming barriers

    Effective implementation of these recommendations will require three inter-related actions from health professionals, care staff, and their employing organisations. Firstly, awareness of delirium as a common and serious illness (“think delirium”) should be improved. The current poor detection of delirium1 should be addressed by education programmes. Use existing clinical codes to document the condition for audits and as an indicator of care quality and outcomes.

    Secondly, staff in hospitals and care homes should adopt a new culture of preventing delirium. This will require: specific education to change attitudes and improve knowledge and skills; a re-design of care systems; and clear clinical and managerial leadership and responsibility, because a whole hospital or a whole care home approach is necessary.

    Lastly, greater involvement of patients and relatives is required to inform timely patient centred care (the key to delirium prevention) and the redesign of care systems (for example, ward noise reduction, maintaining hydration and nutrition).

    Further information on the guidance


    Although delirium is common, recognition of the disorder is poor in the United Kingdom,1 possibly because of a lack of awareness of the condition and difficulties in distinguishing delirium from dementia. In addition, there is a paucity of high quality research on the topic, particularly in long term care settings. Review of the literature shows that delirium can be prevented in about one third of patients at risk by using a multicomponent non-pharmacological intervention in the hospital setting.1 This is a cost effective and cost saving strategy for providers of health and social care; however, current practices and systems to support delirium prevention interventions need to be better developed.


    The guidance was developed by the National Clinical Guideline Centre in accordance with NICE guideline development methods ( This involved systematically searching the literature and critically appraising and summarising the clinical and cost effectiveness evidence. A multidisciplinary Guideline Development Group (GDG) comprising healthcare professionals from secondary care, a care home manager, and patient representatives discussed the evidence and formulated the clinical recommendations. The supporting technical team included individuals with specific expertise in literature search techniques, systematic evidence review, health economics, and project management.

    Health economic evidence was considered during the process of making the guideline recommendations to ensure cost effective use of healthcare resources. This comprised a review of existing published economic analyses that provided evidence on the costs and benefits of interventions (in terms of quality adjusted life years). Health economic evidence was limited, so the GDG and the health economist developed new economic evaluation models for prevention and treatment interventions. They are described in detail in the full guideline.

    The guideline was subject to a web based external consultation with stakeholders. This drew 468 submitted comments, each of which was considered by the GDG for its validity and usefulness. Where deemed appropriate, the guideline was modified in light of these comments.

    NICE has produced four different versions of the guideline: a full version containing all the evidence, the process undertaken to develop the recommendations, and all the recommendations; a quick reference guide; a version containing a list of all the recommendations, known as the “NICE guideline”; and a version for patients and the public. All these versions are available from the NICE website ( Further updates of the guidance will be produced as part of the NICE guideline development programme.

    Key areas for future research
    • In people in hospital who are at high risk of delirium, which medication (that is, atypical antipsychotics, typical antipsychotics, benzodiazepines, or acetylcholinesterase inhibitors), compared with placebo or each other, is most clinically and cost effective in preventing the development of delirium?

    • In people in hospital who have delirium, which is the most effective medication (atypical antipsychotics, typical antipsychotics, or benzodiazepines), compared with placebo or each other, for treating delirium?

    • For people in long term care, is a multicomponent non-pharmacological intervention more clinically and cost effective than usual care in preventing the development of delirium?

    • How common is delirium and what are its adverse outcomes in people in long term care?

    • Does a staff education programme (compared with an educational leaflet or usual care) reduce the incidence of delirium and improve the recognition and recording of delirium in people in hospital?


    Cite this as: BMJ 2010;341:c3704


    • This is one of a series of BMJ summaries of new guidelines based on the best available evidence; they highlight important recommendations for clinical practice, especially where uncertainty or controversy exists.

    • The members of the Guideline Development Group are John Young (chair and clinical adviser), David Anderson, Andrew Clegg, Melanie Gager, Jim George, Jane Healy, Wendy Harvey, Anne Hicks, John Holmes, Emma Ouldred, Najma Siddiqi, Gordon Sturmey, Beverly Tabernacle, Rachel White, and Matt Wiltshire. The members of the technical team are Anayo Akunne, Ian Bullock, Sarah Davis, Bernard Higgins, Paul Miller, Lakshmi Murthy, Rachel O’Mahony, Jill Parnham, Silvia Rabar, Fulvia Ronchi, and Maggie Westby.

    • Contributors: JY was the chair and clinical adviser of the Guideline Development Group, MW and LM the systematic reviewers, AA was the health economist, and RO’M was the project manager for this guidance. LM and JY jointly wrote the first draft of the article. All authors reviewed the draft article critically for important intellectual content and approved the final version to be published. All authors are guarantors of this article.

    • Funding: The National Clinical Guideline Centre was commissioned and funded by the National Institute for Health and Clinical Excellence (NICE) to write this summary.

    • Competing interests: All authors have completed the Unified Competing Interest form at (available on request from the corresponding author) and declare: AA, LM, ROM, and MW have no financial support for the submitted work from anyone other than their employer. JY received an honorarium for chairing the Guideline Development Group; all authors have no relationships with any companies that might have an interest in the submitted work in the previous 3 years; JY has been awarded a programme grant for applied research from the National Institute for Health Research to carry out a programme of research aimed at improving delirium prevention for older people admitted to NHS acute hospitals. All authors were members of the Guideline Development Group for the NICE guideline.

    • Provenance and peer review: Commissioned; not externally peer reviewed.