Neurology - Syncope Flashcards
What causes syncope?
Temporary loss of consciousness due to disrupted blood flow to brain
How are syncopal episodes also known?
Vasovagal episodes
Fainting
What causes a vasovagal episode?
Problem with the autonomic nervous system regulating blood flow to the brain
What can cause a strong stimulus to the vagus nerve leading to syncope?
Emotional event
Pain
Change in temperature
Stimulates parasympathetics, this causes vasodilation leading to drop is blood pressure and cerebral circulation causing fainting
What does the patient feel during the prodrome phase in syncope?
- Hot or clammy
- Sweaty
- Heavy
- Dizzy or lightheaded
- Vision going blurry or dark
- Headache
What may a collateral history describe?
- Suddenly losing consciousness and falling
- Unconscious for a few seconds to a minute
- Twitching, shaking or convulsion which can be confused with a seizure
What is the difference between post-syncope and postictal periods?
Patient feels groggy after fainting
**Postictal **
- Prolonged confusion
- Drowsiness
- Irritability
- Disorientation
Both can have incontinence
What is the prognosis of simple fainting?
No underlying pathology
Harmless
No long-term implications
What are the causes of primary syncope? (simple fainting)
Dehydration
Missed meals
Extended standing in warm environment e.g. school assembly
Vasovagal response to stimuli
What are some secondary causes of syncope?
- Hypoglycaemia
- Dehydration
- Anaemia
- Infection
- Anaphylaxis
- Arrhythmias
- Valvular heart disease
- Hypertrophic obstructive cardiomyopathy
What key features should be elicited in a syncope history?
Features that distinguish syncope from a seizure
- After exercise? Post exercise more likely to be an underlying condition
- Triggers?
- Do they have a fever or signs of infection?
- Injury secondary to the faint? Do they have a head injury?
- Palpitations or chest pain?
- Any neurological symptoms?
- Seizure activity?
- Family history, particularly cardiac problems or sudden death?
Learn these differences
What key points should be focused on during examination?
- Any injuries e.g. head from fainting
- Any illness at same time, e.g. gastroenteritis
- Neurological exam
- Cardiac exam
- Lying and standing BP
What investigations should be done for patients with syncope?
- ECG
- 24 hour ECG
- Echocardiogram
- Bloods, FBC, U&Es and BM
What advice should be given to patient and family after a vasovagal episode?
- Avoid dehydartion
- Avoid missing meals
- Avoid standing still for long periods
- If experiencing prodromal symptoms, sit or lie down, have water and something to eat
