Delirium, Confusion and Assessing a Confused Patient

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1 in 5 elderly patients on medical and surgical wards are affected by delirium at any one time.1 Delirium is a symptom of an underlying cause which needs to be elucidated and treated. It is also important to differentiate between delirium, depression and dementia – something which can be incredibly difficult in practice.


Delirium: an acute, transient and reversible state of confusion, usually the result of other organic processes (infection, drugs, dehydration), the onset is acute and the cognition of the patient can be highly fluctuant over a short period of time.



There are 2 main types of delirium:

  • Hyperactive
  • Hypoactive

Note that fluctuation between the two is common.


Hyperactive delirium

This is the ‘typical’ delirium picture:

  • Agitation
  • Delusions
  • Hallucinations
  • Wandering
  • Aggression


Hypoactive delirium

Hypoactive delirium is much easier to miss.

Often this type of delirium can be confused with depression.

Symptoms include:

  • Lethargy
  • Slowness with everyday tasks
  • Excessive sleeping
  • Inattention

Causes and Risk factors

A change in environment coupled with sensory impairment (common in the elderly) increases the risk of developing delirium. These factors alone can cause delirium without any deeper organic cause, but this should only be considered as a diagnosis of exclusion. Things that can cause or lead to delirium include pretty much anything, ever. Some of the biggies are listed below. I’m generally not a fan of acronyms for the sake of acronyms, but CHIMPS PHONED is a useful reminder that it is not just our old friend UTI that should be considered:

  • Constipation
  • Hypoxia
  • Infection
  • Metabolic disturbance
  • Pain
  • Sleeplessness
  • Prescriptions
  • Hypothermia/pyrexia
  • Organ dysfunction (hepatic or renal impairment)
  • Nutrition
  • Environmental changes
  • Drugs (over the counter, illicit, recreational, their partner/neighbour/pets’, alcohol and smoking)

Assessment of the confused patient


Clues from the medical notes

  • Current diagnoses – consider dementia and depression as standalone causes or in conjunction with delirium
  • Medications – perform a medication review
  • Vascular problems (e.g. previous strokes, myocardial infarctions, ischaemic limbs) – increased likelihood of vascular dementia
  • Other presenting complaints
  • History of recurrent admissions



  • A useful, quick method to gain an objective assessment of cognition
  • Can be repeated to allow ongoing recognition of improvement/deterioration
  • Also, consider the use of a more formal screening tool (MMSE/ACE-III)



  • Get the best history from the patient as possible – conversation can give big clues to the patient’s current mental state
  • Reassurance and gentle re-orientation if appropriate – ask the patient what they are seeing/hearing/experiencing
  • Collateral history – What is normal for the patient? How long have they been confused? What is different?

The “Confusion Screen” – Which tests and why?

Vital signs

  • Measuring vital signs is a useful tool for identifying patients who are unwell and triggering medical review/intervention.
  • Vital signs include the following measurements: blood pressure, heart rate, respiratory rate, oxygen saturation level, temperature and level of consciousness
  • The presence of fever may indicate an underlying infection (+/-sepsis).
  • The presence of tachycardia and hypotension may suggest underlying dehydration or sepsis.


CT head

Neuroimaging is a useful tool in the context of confusion to rule out intracranial pathology such as:

  • Ischaemic stroke
  • Intracranial bleeding
  • Space occupying lesions


Bloods tests

Most hospitals often have a panel of blood tests bundled together as a “confusion screen” to help rule out common underlying causes of confusion:

  • FBC (e.g. infection, anaemia, malignancy)
  • U&Es (e.g. hyponatraemia, hypernatraemia)
  • LFTs (e.g. liver failure with secondary encephalopathy)
  • Coagulation/INR (e.g. intracranial bleeding)
  • TFTs (e.g. hypothyroidism)
  • Calcium (e.g. hypercalcaemia)
  • B12 + folate/haematinics (e.g. B12/folate deficiency)
  • Glucose (e.g. hypoglycaemia)
  • Blood cultures (e.g. sepsis)


Chest X-ray

  • Often performed to rule out pneumonia (if clinical signs suggestive of the diagnosis)


Urine tests

  • UTI is a very common cause of delirium in the elderly.
  • Positive urine dipstick without clinical signs is NOT satisfactory to diagnose urinary sepsis as a cause of delirium.2, 3
  • Look for other evidence supporting the diagnosis (WCC↑/supra-pubic tenderness/dysuria/offensive urine/positive urine culture).
  • In the meantime, ensure you are considering other differential diagnoses.

Management of Delirium

Identify and treat the underlying cause

  • To definitely treat delirium, the underlying cause needs to be identified and treated.


Supportive management

  • Try to keep a consistent nursing and medical team, gentle re-orientation, calm and consistent care, regular introductions of yourself and your role, clear and concise communication.
  • Ensure the patient has access to aids such as glasses, hearing aids and walking sticks where appropriate.
  • Enable the patient to do what they can for themselves – independent washing, dressing, eating, toileting and other activities may still be possible with varying levels of encouragement.


Environmental adaptation

  • Ensure there is access to a clock (and other orientation reminders for the day, date, time etc),
  • Have some familiar objects where possible – having photographs available, using the patient’s own clothes/washcloths.
  • Involve the family, friends and/or carers in the care of the patient.
  • Control level of noise around the patient.
  • Ensure lighting is adequate and the temperature is ambient.



  • Avoid where possible.
  • Persistent wandering and delirium are not absolute indications for sedation.
  • Aim to keep the patient safe by the least restrictive method.
  • Use of drugs can worsen delirium and come with their own adverse effects.
  • Haloperidol (oral, IV or IM) is usually the first-line medical option, starting with a low dose in the elderly (0.5mg), which can be repeated after 30 minutes if no response is seen.
  • If benzodiazepines are to be used, lorazepam is first-line (0.5mg starting dose) due to its rapid onset and short half-life. See the NICE Guidance for further management.6



  • Families/carers need to be aware that delirium can continue for a period of time after the cause has been treated.
  • Information should be given to those surrounding the patient on the management of any residual disorientation or inattention.
  • Follow-up is advisable.


Prevention is better than cure…

  • Avoid drugs known to precipitate delirium (e.g. opiates and benzodiazepines).
  • Highlighting patients more ‘at risk’ and observing them closely for signs of delirium.
  • Assessment of other factors which may induce or exacerbate delirium (e.g. pain control, drugs etc)6
  • Employing supportive/environmental management approaches for all patients, regardless of delirium risk.


  1. Oxford Handbook of Clinical Medicine, 8th Ed, p488
  2. Beveridge, Davey, Phillips, McMurdo (2011), Optimal Management of Urinary Tract Infections in Older People, Clin Interv Aging. 2011; 6: 173–180. Available from: [LINK
  3. Woodford, George (2009) Diagnosis and Management of Urinary Tract Infection in Hospitalized Older People, J Am Geriatr Soc. 2009 Jan;57(1):107-14. Available from: [LINK]
  4. McMurdo, Gillespie (2000) Urinary tract infection in old age: over-diagnosed and over-treated. Age & Ageing (2000)29 (4):297-298
  5. SIGN (2012), 88: Management of Suspected Bacterial Urinary Tract Infection in Adults: A Clinical Guideline. Available from: [LINK]
  6. Delirium, NICE Clinical Guideline (July 2010). Available from: [LINK]


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