Delirium

1. Acute Onset with Fluctuating Course

• Develops rapidly over hours to days.
• Characterized by lucid intervals interspersed with daily fluctuations.
• Gross swings in attention and awareness, with worsened symptoms at night.

2. Transient Disturbance of Consciousness

• Clouding of consciousness and inattention.
• Patients are easily distractible, with trivial stimuli often gaining more attention than important ones.

3. Confusion or Disorganized Thinking

• Inability to maintain a clear, coherent, and speedy stream of thought.
• Jumbled thinking and speech that shifts from subject to subject, rambling, tangential, and circumlocutory.
• Decreased relevance of speech content, decreased reading comprehension, and abnormal speech rate with frequent dysarthria and nonaphasic misnaming, especially of words related to stress or illness.

4. Altered Level of Consciousness

• Clarity of awareness may be disturbed, with most patients showing lethargy and decreased arousal.
• Some patients, particularly those with delirium tremens, are hyperalert and easily aroused but still have attentional deficits.
• Both extremes of consciousness may overlap or alternate in the same patient.

5. Disturbed Sleep/Wake Cycle

• Disruption of the day/night cycle causing excessive daytime drowsiness and reversal of the normal diurnal rhythm.
• “Sundowning” (restlessness and confusion during the night) is common, with delirium often manifesting only at night.

6. Altered Psychomotor Activity

• Hypoactive-Hypoalert Subtype: Psychomotor retardation with lethargy and decreased arousal.
• Hyperactive-Hyperalert Subtype: Agitation and hyperalertness with prominent autonomic overactivity, delusions, and hallucinations.
• About half of patients fluctuate between both subtypes; approximately 15% are strictly hyperactive. Hyperactive subtype is often drug-related, has a shorter hospital stay, and a better prognosis.

7. Perceptual Disturbances

• Decreased perception per unit of time, leading to missed environmental cues.
• Illusions and misperceptions from abnormal sensory discrimination.
• Hallucinations (mostly visual) that are vivid, three-dimensional, and in full color, typically unpleasant. These may be release phenomena with dream intrusions into wakefulness.
• Psychotic auditory hallucinations are uncommon.

8. Disorientation

• Disorientation first to the time of day, followed by other aspects of time, and then to place.
• Disorientation to person (loss of personal identity) is rare.
• Common in delirium but not specific, as it also occurs in dementia and amnesia.

9. Memory Impairment

• Recent memory impairment primarily due to attentional problems causing decreased registration of new information.

Common causes include (multiple often):

1. non medical
   • Environmental Factors:
     • Unfamiliar people
     • Unfamiliar surroundings: Being in a new or unfamiliar environment.
     • Changes to routines: Disruptions to established daily schedules.
     • Changes to usual environment: Alterations to the familiar living or working space
     • Lack of personal belongings
   • Cultural and Social Factors:
     • Cultural background: Influence of cultural practices and beliefs.
     • Language barriers: Difficulty in communication due to language differences.
     • Preferred language not being used: Inability to express oneself in the language of choice.
   • Sleep and Fatigue:
     • Insomnia / tiredness / sleeping problems: Lack of sleep or poor sleep quality leading to cognitive disturbances.
2. Medication-related Factors:
   • Medication adverse effects: Side effects of medications affecting cognitive function.
   • Medication interactions: Negative interactions between different medications
   • Intoxication: sedatives/ anti-cholinergics/ digoxin/ anti-epileptics
   • Withdrawal: sedatives/ alcohol (prominent visual halls & symp overact)
3. Progression of disease
   • Demential
   • anxiety
   • depression
4. Hypoxia
5. Infection
   • Systemic
   • UTI
   • Pneumonia
   • Otitis media/externa
6. Vascular
   • MI
   • CVA
7. Intracranial pathology
   • CVA
   • Subdural/ SAH
   • Tumour
   • Encephalitis
   • Meningitis
   • Postictal
8. Metabolic disturbances
   • Electrolytes- hypo/hypernatraemia/ hypocalcaemia
   • Hypoglycaemia
   • Endocrine- thyroid/ cushings
9. Mechanical
   • Constipation
   • Urinary retention

DDx

• Uncomplicated dementia
• Depression
• Psychosis- normal cognition
• Mania

	Delirium	Demetia	Psychosis
Onset	Sudden	slow onset	variable onset
Course	fluctuation	progressive	variable
Consciousness	clouded, worse at night	alert	alert
Attention	Disordered	impaired	Disordered
Hallucinations	visual – related to ext stimuli	rare	auditory hallucinations – related to int stimuli
Cognition	Disordered	impaired	impaired
Orientation	impaired	Often OK	impaired
vitals	often abN	normal	normal

Immediate assessment according to ABCD

1. Airway- patency/ ability to protect
2. Breathing
   1. RR/ Sats
   2. High flow O2 by face-mask (hypoxia!)
3. Circulation
   1. PR/ BP/ peripheral perfusion
   2. IV access + gentle fluid challenge
      1. Bloods
         1. FBC- leucocytosis/ anaemia
         2. ESR/ CRP
         3. EUC/ CMP- ARF/ electrolyte disturbance
         4. LFT- encephalopathy/ biliary obstruction/ baseline
         5. BSL- hypoglycaemia
         6. Troponins- MI
         7. TSH
         8. Drug levels- digoxin/ anti-epileptics
         9. ABGs
   3. Titrate fluids to response
4. GCS/ AVPU

Collaborative Hx

5. Family
   1. Recent precipitants
      1. Biological– localising sxs
         1. SOB/ cough/ wheeze
         2. Dysuria/ frequency/ incontinence
         3. Chest pain/ neck or shoulder pain
         4. Abdo pain/ diarrhoea/ constipation/ PR bleeding
         5. Weakness/ imbalance/ visual disturbance/ falls
         6. Medications & drugs
      2. Psychological
         1. Depression
      3. Social
         1. Change of environment
   2. Risk factors for delirium
      1. Pre-existing dementia
      2. Physical co-morbidities
         1. CVD- MI/ angina/ hypt/ DM/ chol/ smoker
         2. CVA
         3. Resp disease
         4. Renal failure
         5. Cancer
      3. Medications
         1. Polypharmacy > 6 meds
         2. High-risk drugs
            1. Sedatives- benzos/ alcohol
            2. Anticholinergics
            3. Opioids
            4. Corticosteroids
      4. Psychological problems
         1. Depression
            1. TCAs
         2. Anxiety
   3. Social Hx
      1. Living arrangements/ social supports
      2. Premorbid functional capacity
         1. ADL/ IADL
         2. Mobility
         3. Cognitive
      3. Legal considerations
         1. Advanced care directives
         2. Enduring power of attorney
         3. Guardianship
      4. Etoh/ smoking/ substance abuse

Physical examination

6. Vital signs- PR/ BP/fever/sats
7. Hydration status
8. Mental status
   1. CCF- IHD/ Valvular HD/ Hypertensive HD/ Cardiomyopathy
   2. Respiratory failure Pneumonia/PE. COPD
   3. Abdo + PR – Acute abdomen/Perforation/Obstruction/Mesenteric infarction/Strangulated herniaOrganomegaly/ ascites/ Faecal loading
   4. Neuro
      1. Level of consciousness- GCS + pupils
      2. Orientation/ higher function
      3. Raised ICP- papiloedema
      4. Neurological deficit- CN/ UL/ LL
      5. Non-specific
         1. Asterixis- most
         2. Frontal lobe release signs
            1. Picking at bedclothes
            2. Grasping at catheters
   5. Limbs: DVT/Acute PVD/Ulcers/Fractures

2. Investigations
   1. ECG-new or old ischaemic changes/ arrhythmia/ PE
   2. Blood glucose
   3. Urinalysis
   4. Septic screen- FBC/ ESR/ CRP
   5. Metabolic screen- EUC/ CMP/ LFT/ BSL/ TSH/ B12/ Folate
   6. Troponin
   7. MSU- M/C/S
   8. Blood cultures x 2 sets
   9. Others as indicated- sputum/ wound
   2. Imaging
      1. CXR +/- AXR
      2. CT head- CVA/ subdural
   3. Others as indicated
      1. TTE
      2. Abdo US
      3. CT abdomen
      4. LP

Management

SHORT TERM

1. Non- pharmacological
   1. A/B- O2 – maintain Sats > 93%
   2. C- fluid & electrolyte management 
   3. Nursing care orders
      1. Safe/ calm/ quiet environment
      2. Single room/ single nurse
      3. Adequate stimulation- soft lighting
      4. Re-orienting cues- clock/ photos
      5. Clear, slow communication
      6. Approach from the front (less hostile)
      7. Observe at all times- unpredictable behaviour

2. Pharmacological
   1. Treat underlying cause
      1. Thiamine- always if cause is unknown
      2. Infection- Axs
      3. Nutrition
      4. Review medications
   2. Treat complications
      1. Analgesia
      2. Anticoagulation
      3. Anti-constipation- coloxyl & senna

NB- most delirious pts do NOT need Rx with medications

Cautions in the use of psychotropics

• Use the oral route if possible
• Monitor vital signs closely during & after administration
• DO NOT give IM diazepam- poor/ erratic absorption
• AVOID IV midazolam- risk of respiratory depression
• AVOID ALL benzos in pts with significant respiratory depression
• Use low flow O2 rates b/c of potential for benzos to suppress hypoxic resp drive
• Monitor intensively if repeated doses are given
• Keep an accurate record of meds given

3. Psychotropics
   1. Indications
      1. Distressful hallucinations or delusions
      2. At risk behavioural disturbances- pt/ staff/ others
   2. Use low-dose antipsychotics
      1. Haloperidol PO titrate to response (max 20mg/day)
         1. Adults- 1.5-10mg
         2. Elderly/ frail- 0.5mg
      2. Haloperidol IM (if PO not possible) single dose
      3. Risperidone PO 0.5-2.0 mg/ day
      4. Olanzapine PO 2.5-10 mg/ day
      5. Quetiapine 25-200mg /day

4. Sedatives
   1. Indications
      1. Severe anxiety
      2. Agitation inadequately controlled by haloperidol
   2. Use PO (preferred)
      1. Diazepam PO single dose; repeat at 1 hr if nec
         1. Adults- 5-10mg 
         2. Elderly/ frail- 2mg
   3. Use IM (if required)
      1. Midazolam IM single dose
         1. Adults- 2.5-5mg
         2. Elderly/frail- 1.25 mg
      2. Monitor closely for 4 hrs (sedation/ hypot/ resp dep)
   4. Use IV (if required for rapid sedation)
      1. Diazepam IV over several mins; single dose- titrate
         1. Adults- 5-20mg
         2. Elderly/frail- 2mg

5. Antidotes
   1. Extrapyramidal SEs (typical antipsychotics)
      1. Benztropine PO/IM 1-2 mg
      2. Benzhexol PO 2mg
      3. NB- anti-cholinergic SEs may worsen delirium!!
   2. Benzo reversal
      1. Flumazenil IV 0.1mg/ min (max 1.0mg)
      2. ½ life = 1 hr; repeat doses may be needed

LONG TERM

Family meeting

1. Explanation of diagnosis & strange behaviours/ ideas
2. Reassurance
3. Family wishes

Multidisciplinary review + family meeting

1. Geriatrician
   1. Cognitive assessment- MMSE
   2. Review medications
   3. Optimise medical care
2. Allied health
   1. Physio
      1. Chest physio
      2. Mobility
      3. Function
   2. OT
      1. Personal & shower assessment
      2. Home assessment & modification
   3. Social worker
      1. Family counselling
      2. Arrange community resources
   4. Community pharmacist
      1. Webster pack
      2. Blister pack
   5. Discharge planner
      1. Suitability for D/C
         1. Self-care
         2. Safe
         3. Access to community resources
      2. Medical discharge letter- GP
         1. Cause/ Ixs/ treatment/ changes
      3. Appropriate F/U
         1. GP
         2. Geriatrician
         3. Psychogeriatrican
   6. ACAT Assessment
      1. Home assessment, Community services, Community nursing, Domestic services
      2. Meals on wheels