Delirium

• Delirium is 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 two main states of delirium, known as ‘hyperactive‘ and ‘hypoactive‘ delirium
• Hyperactive delirium:

  • Agitation
  • Delusions
  • Hallucinations
  • Wandering
  • Aggression
• Hypoactive delirium:

  • Lethargy
  • Slowness with everyday tasks
  • Excessive sleeping
  • Inattention
• 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
• Common causes of delirium:

  • Constipation
  • Hypoxia
  • Infection
  • Metabolic disturbance
  • Pain
  • Prescriptions/drugs
  • Hypothermia/pyrexia
  • Organ dysfunction (hepatic or renal impairment)
  • Nutrition
  • Environmental changes
• Cognitive assessment:

  • Abbreviated mental test 4 (AMT-4) for screening - age, DOB, place, year
  • MMSE and ACE-III for more detailed assessment
  • 4AT diagnoses delirium - alertness, AMT4, attention, acute change or fluctuating course
• Clinical examination:

  • Vital signs
  • Level of consciousness (GCS/AVPU)
  • Evidence of head trauma
  • Sources of infection e.g. suprapubic tenderness
  • Asterixis e.g. uraemia/encephalopathy
• Confusion screen:

  • FBC - infection, anaemia, malignancy
  • U&Es - hypo/hypernatremia
  • LFTs - liver failure
  • Coagulation/INR - intracranial bleeding
  • TFTs - hypothyroidism
  • Calcium - hypercalcaemia
  • B12 + folate/haematinics
  • Glucose
  • Blood cultures
  • Urinalysis
• Imaging:

  • CT head if there is concern about intracranial pathology
  • CXR
• Management:

  • Identify and manage underlying cause
  • If distressed - first use verbal and non-verbal techniques to de-escalate
  • If considered a risk to themselves or others - use short term haloperidol - start at lowest clinically appropriate dose
  • Elderly IM = 500 micrograms
  • Lorazepam can also be used