Blackouts Flashcards
How can you differentiate between a fall an a collapse?
Ask the patient if they remember falling and if they remember hitting the ground. If yes, it is a fall. If no, it is a collapse.
What features suggest syncope?
Triggering factor, distinct prodrome, ‘convulsion’ after LoC and less than 15 seconds, short duration, quick recovery, ongoing lethargy but no confusion.
What features suggest seizures?
Aura, automatisms, convulsions at onset of LoC, longer duration, post-ictal phase, tongue biting, incontinence.
What are the four big causes of blackouts and hoe do they typically present?
- Syncope - light headedness, nausea, tunnel vision
- Seizure - fit, tongue/urine, post-ictal
- Stroke/TIA - unilateral weakness/sensory loss, speech, face
- Cardiogenic - palpitations
What is the pathophysiology of vasovagal syncope?
Reflex bradycardia and peripheral vasodilation provoked by emotion, pain, or standing too long.
What symptoms typically precede vasovagal syncope?
Nausea, pallor, sweating, narrowing of visual fields.
How long does vasovagal syncope last and how quickly do people recover?
- <2 minutes
2. Rapid recovery
What is this a presentation of?
Vasovagal syncope symptoms but brought on by exercise (cardiac), or during/after urination (mostly in men, at night).
Situational syncope - cough/effort/micturition
What is this describing?
Hypersensitive baroreceptors cause excessive reflex bradycardia +/- vasodilation on minimal stimulation (e.g. head turning/shaving).
Carotid sinus syncope
What is this a presentation of?
Attacks when asleep/lying down, aura, identifiable triggers, altered breathing, cyanosis, tonic-clonic movements, incontinence of urine, tongue-biting, prolonged post-ictal drowsiness, confusion, amnesia.
Epilepsy
What is this a presentation of?
Unilateral weakness, sensory loss, slurred speech, facial asymmetry.
Stroke/TIA
What is this a presentation of?
Patient falls to the ground often with no warning except for palpitations, injuries common, pale, slow/absent pulse, recovery in seconds.
Stokes-Adams attack
What is the cause of a Stokes-Adams attack?
Transient arrhythmias cause reduction in CO and LoC.
What is this a presentation of?
Tremor, hunger, perspiration, rare in non-diabetics.
Hypoglycaemia
What are the causes of hypoglycaemia?
Poorly controlled diabetes, alcohol, liver failure, adrenal insufficiency, insulinoma.
What is this a presentation of?
Unsteadiness or LoC on standing from lying in those with inadequate vasomotor reflexes, elderly, autonomic neuropathy, antihypertensive medications, overdiuresis.
Orthostatic hypotension
What is this a presentation of?
Hyperventilation, tremor, sweating, tachycardia, paraesthesia, light-headedness, no LoC.
Anxiety attack
What is this a presentation of?
Sudden fall to the ground without LoC, mostly benign and due to leg weakness.
Drop attack
What is this a presentation of?
Gradual onset, prolonged, abrupt termination, closed eyes, resistance to eye opening, dyssynchronous blackout.
Factitious blackout (Munchausen’s)
What is it important to ask someone who has just had a blackout?
- Lose awareness? Injury themselves? Stiff/floppy? Movements?
- Incontinence? Complexion change? Tongue biting? Other symptoms?
- How long? When did it start? More/less frequent? Anyone in family get them? History of birth injury/CNS infections?
What should you ask about before a blackout?
- Any warning? Aura/pre-syncope?
- In what circumstances do attacks occur?
- Can the patient prevent them?
What should you ask about after a blackout?
- How much does the patient remember?
- Muscle ache?
- Confusion/sleepiness?
- Injuries sustained?
What are the typical initial syncope investigations?
- Cardiac assessment - ECG
- Metabolic assessment - calcium, U&Es, magnesium, glucose
- ABG, low PaO2 suggests hyperventilation
