Delirium / Confusion Flashcards
You have been asked to see an 89-year-old lady in A&E. She has been admitted with confusion from a nursing home. She has a background of hypertension, previous myocardial infarction, chronic obstructive pulmonary disease and chronic kidney disease. The nursing staff at the home are concerned that she has become increasingly confused over the last week. She is not drinking or eating properly and has not been able to mobilise out of bed for the last two days. She was seen by her GP 2 days ago who started her on antibiotics for a possible urine infection. Her current observations are as follows:
Blood pressure: 109/67
Heart Rate: 104 bpm
Respiratory rate: 22
Saturations: 94% on room air
Temperature: 37.8 degrees
How would you approach this patient?
I would first start with the ABCDE approach
A
* Patent airways? Pt talking?
B
* Move onto measuring SpO2 and RR, if signs of hypoxia»_space; supplemental oxygen
* Auscultate lung fields for signs of infection, fluid overload
C
* Monitor HR and BP, ask nurse for ECG
* Measure CRT (peripherally and centrally)
* Establish IV access and take bloods at the same time, look for intravascular depletion (tongue and mucosal membranes), if depleted > IV fluids
* Monitor Urine Output – if very drowsy, catheter might be needed, but can cause UTI in the elderly
D
* Glucose
* Temperature
* GCS and AMTS
**E **– Finally, I would do a full examination, checking the abdomen and limbs for signs of infection or a cause of the PC, as well as a neurological exam
What is your differential diagnosis in an acutely confused patient?
Systemic disorders:
* Sepsis (urinary, respiratory)
* Metabolic disorder: Vitamin deficiency, Endocrine disease (Thyroid disorders, adrenal cortex disorders)
* Electrolyte disturbances: hyper or hypo Glu; Na; Ca
* Myocardial ischaemia (causing hypoperfusion)
* Organ failure (hepatic, renal, and others)
* Uraemia in CKD
Drugs and Toxins
* Overdose
* Alcohol intoxication / withdrawal
* New changes in medications (e.g. new anti-psychotic)
* Use of Diuretics (hypoN, hypoK, hyperCa - thiazides, hypoMag)
* Use of Digoxin - narrow therapetic index»_space; neurotoxicity, toxic accumulation in renal failure
* Use of Thyroid meds
CNS Disorders
* I - meningitis, encephalitis, brain abscess
* N - malignancy/ tumour / SoL
* V - ischaemic/haemorragic stroke
* I - cerebral vasculitis
* T - subdural / extradural haematoma
* Others - Post-ictal; Non-convulsive state
What investigations will you initiate in an acutely confused patient?
Septic screen
* FBC, CRP, Blood cultures, midstream urine analysis, urine MC&S
* Chest radiograph
Metabolic screen
* VBGs (hypercapnia, uraemia, DKA, acid-base balance, lactate)
* U&Es including calcium
* Thyroid function
* LFTs (liver failure»_space; hepatic encephalopathy)
* Thiamine, folate, vitamin B12 levels
Check prescribed medications, request drug levels of any meds I am concerned about (digoxin, lithium)
Organise a CT head to look for ICH, SOL, subdural haematoma
If suspected a CNS infection > perform an LP
What LP results might suggest a bacterial meningitis?
- LP will be sent for cell count, gram stain, MC&S, protein and glucose (with a matched serum sample)
- Appearance - clear, cloudy, purulent
- WBC - generally > 100 cells/microL (usually >90% Polymorphonuclear neutrophils)
- Glucose will be < 40% of serum glucose
- Protein will be elevated > 50 mg/L
How do you treat acute confusional states?
- Resuscitation - ABCDE - correct hypoxia, hydration etc
- Identify and treat the cause - may include antibiotics (local guidelines)
-
Confusion - many conservative measures
* Ensure pt not left unattended
* Same staff day after day
* Ensure they have their glasses, hearing aids
* Discontinue meds that may be contribution to confusion
Antidepressants, antihistamines, opioids, benzos
- Promote good sleep hygiene
- Consider hydration and nutrition
If suspect thiamine deficiency 2nd to alcoholism / malnutrition»_space; Pabrinex
-
Sedation - if pt becomes aggressive/risk to themselves/others - should be a measure of last resort
* Haloperidol - 30-60 min - avoid in QT prolongation, Parkinson’s, Lewy body dementia
* Lorazepam - 5-10 min
How would you assess acute confusion on admission? (Cognitive tests)
AMTS, CAM
What is the difference between delirium and dementia
Delirium - a reversible transient impairment of one’s cognitive ability and consciousness
Dementia - a progressive and irreversible decline in global function from a premorbid level, without any impairment in consciousness
What factors predispose a patient to delirium?
- Age > 65
- Dementia
- Multiple comorbidities
- Polypharmacy
- Visual and hearing impairment
- Recent surgery
- Drugs and alcohol dependence
What are the causes of dementia?
Primary
* * Neurodegenerative - Alzheimer’s, Parkinson’s, Frontotemporal Dementia, CJD
* Others: Vascular dementia, normal pressure hydrocephalus
Secondary
* Infectious: Syphilis, HIV
* Vascular: cerebrovascular disease, subdural haematoma*
* Drugs: Heavy metal exposure (lead, cadmium, manganese)
* Metabolic
a) B12, folate, thiamine deficiency*
b) Hypothyroidism*
c) Cushing’s syndrome*
d) Wilson’s disease
*Reversible causes
How would you investigate a possible diagnosis of dementia?
- Order blood tests for reversible causes of dementia and investigations
- Folate, thiamine, B12, TFTs, CT head (subdural haematoma)
- More specialised tests (ceruloplasmin - Wilson’s) should be performed only after discussion with a senior
- If suspected dementia, discuss potential diagnosis with the patient and ask GP on discharge to refer them to the memory clinic
What phatmacological treatment is available for the treatment of Alzheimer’s?
- Acetycholinesterase inhibitors - Donepezil - moderate Alzheimer’s
- An NMDA receptor antagonist - Memantine - severe Azlheimer’s
Treatment should be only initiated by a specialist in dementia
