Transient loss of consciousness Flashcards
What are the ‘big three’ for a differential diagnosis of TLOC?
- Epileptic seizure
- Syncope
- Psychogenic nonepilpetic seziure
Define a seizure
Clinical manfestation of abnormal and excessive discharge of cerebral neurones
Causes of a seizure
May be due to epilepsy, may be the first seizure, may be an acute symptomatic seizure
Define epilepsy
a tendency to experience recurrent unprovoked epileptic seizures
two important factors which cause different clinical manifestations of a seizure
where the seizure arises from
where the seizure spreads to
What is a focal onset of an epileptic seizure?
- Simple, partial seziure [aura]
- Complex partial seziures
- Secondary generalized tonic clonic seziures [GTCS]
Structural cause
Focal onset is one, what is the other type of onset for ES? How do they present?
Generalized tonic clonic seizures [GTCS]
Moyclonic jerks
Absences
Causes of generalized onset seizures
Idiopathic/genetic cause
family history
Early morning seizures, worse with sleep deprivation or alcohol, photosensitivity
What does an absence seizure look like on an EEG?
slides
When is the only time you should talk about ‘absence seizures’?
Only if you mean a clinical absence seizure associated with a 3 second spike and wave on the EEG.
Otherwise, use ‘loss of awareness’ or ‘vacant spell’.
Lots of seizures can cause somebody to briefly lose awareness, not just absence seizures.
What is the technical term for syncope?
Transient global cerebral hypoperfusion
Three main causes for a syncope
Reflex [nuerally mediated]:
- VASOVAGAL
- situational
- carotid sinus hypersensitivity
Cardiogenic
Orthostatic hypotension
- drugs, autonomic failure
Cause for cardiac syncope
- Condiitons that predispose to transient tachyarrhythmias
- Bradyarhythmias
- Cardiac ischaemia
- Structural heart disease
What would a cardiac syncope look like on an ECG?
slides
What would Wolff-Parkinson-White look like on an ECG?
slides
What would Brugada syndrome look like on an ECG?
slides
What is Brugada syndrome?
look up
Arrythmogenic right ventricular dysplasia on ECG
slides
learning point 2: what do conditions that give rise to transient tachyarrhythmias look like on an ECG?
What can these conditions cause?
What should you ALWAYS do on a patient with TLOC?
Have an abnormal ECG between events
These conditions cause sudden death in young people
Do an ECG in pts with TLOC
Which type of heart block have a high risk of progression to asystole?
Complete [3rd degree] heart block
Moritz type II 2nd degree heart block
incomplete trifascicular block
- RBBB
- LAD
- 1st degree heart block
how does acute ischaemia cause syncope?
Causes syncope due to arrhythmia, output failure or acute mitral regurgitation