Delirium

Question 1

CAUSES:

1. Systemic Illness
2. Drugs
3. Intracranial causes

Answer 1

1. a) Infections and sepsis
   b) Anoxia: MI, Respiratory/heart failure
   c) Metabolic and endocrine: thyroid, parathyroid, hypopituitarism, adrenocortisol, uraemia, porphyria, hepatic encephalopathy, electrolyte disturbance, hypoglycaemia
   d) Nutritional: Thiamine, vitamin B12, folic acid, niacin deficiencies
2. a) Prescribed: Antiparkinsonian drugs, opiates, steroids, anticholinergics, benzodiazepines, antispasmodics
   b) Recreational: Alcohol, opiates, cannabis, amfetamines
   c) Poisons: Heavy metals, Carbon monoxide
3. Intracranial causes
   a) Space-occupying lesions: tumours, cysts, abscesses, haematomas
   b) Head injury: concussion
   c) Infection: Meningitis, encephalitis
   d) Epilepsy
   e) Cerebrovascular disorders: TIA, cerebral thrombosis/embolism, Intracerebral/SAH, hypertensive encephalopathy, vasculitis

Question 2

RISK FACTORS:

Answer 2

1. Abnormal brain:
   - Dementia
   - Previous injury
2. Age
3. Polypharmacy
4. Sensory impairment
5. Vulnerable brain
   - eg: dehydration, constipation, UTI

Question 3

CLINICAL FEATURES:

Answer 3

1. Impaired consciousness
   - hypoactive/hyperactive
   - impaired attention
2. Impaired cognitive function
   - Disorientation to time and place but usually preserved orientation to self
   - Language abnormalities
3. Perceptual and thought disturbance
   - misinterpretations, illusions, delusions, hallucinations
4. Sleep-wake cycle disturbance
5. Mood disturbance

Question 4

CAUSES OF AMNESIC SYNDROME:

1. Diencephalic damage
2. Hippocampal damage

Answer 4

1. a) Vitamin B1(thiamine) deficiency(Korsakoff’s):
   - Chronic alcohol abuse
   - Gastric carcinoma
   - Severe malnutrition
   - Hyperemesis gravidarum
   b) Bilateral thalamic infarction
   c) MS
   d) Post SAH
   e) Third ventricle tumours/cysts
2. HIppocampal damage:
   a) Bilateral posterior cerebral artery occlusion
   b) CO poisoning
   c) Closed head injury
   d) HSV encephalitis
   e) Transient global amnesia

Question 5

EPIDEMIOLOGY:

Answer 5

1. 10-30% of medically ill, hospitalised patients

2. 10-15% of admissions >65y

Question 6

MANAGEMENT:

Answer 6

1. Hospitalization since medical emergency
2. History and Examination:
   - find out underlying cause
   - Kardex for potential drug-causes
   - Cognitive tests
3. Investigations:
   - Routine: FBC, U&E, LFT, CRP, Calcium, glucose, CXR, ECG, urinalysis
   - If indicated: TFT, blood culture, urine culture, CT head, Lumbar puncture, EEG, ABG
4. Optimise environment
   a) Consistent, reassuring nursing staff
   b) Optimise sensory perception ie visual acuity and hearing
   c) Orientation aids eg clock, familiar objects
   d) Encourage presence of friend/family member
   e) Quiet, peaceful room
   f) Use Butterfly scheme/”Getting to know me”
5. Medication:
   - For unmanageable agitation/distress: Haloperidol 0.5-1 mg ORAL(max 2mg/24h)/Haloperidol 0.5 mg IM(max 2mg/24h)/low-dose 2nd generation antipsychotic eg Risperidone 0.25mg/day titrated
   - Avoid in Lewy body dementia and Parkinson’s disease. If antipsychotics contraindicated, Lorazepam 0.5-1mg ORAL(max 2mg/24h)/Midazolam 2.5 mg IM(max 7.5 mg/24h)
   -
   - Benzodiazepines if needed for substance withdrawal
6. Review legal status

Question 7

ICD-10 CRITERIA(DELIRIUM NOT INDUCED BY ALCOHOL AND OTHER PSYCHOACTIVE SUBSTANCES):

Symptoms present in each one of following areas:

*rapid onset, course diurnally fluctuating, total duration <6/12

Answer 7

a) Impairment of consciousness and attention
b) global disturbance of cognition
- perceptual distortions, illusions, hallucinations, transient delusions
- disorientation for time, in more severe cases, place and person
c) psychomotor disturbance
- hypo/hyperactivity
- unpredictable fluctuations
d) disturbance of sleep-wake cycle
- insomnia/reversal of sleep-wake cycle
- nightmares may continue as hallucinations on wakening
e) emotional disturbances
- depression, anxiety, irritability, fear, euphoria, apathy, wondering perplexity