Transient Loss of Consciousness

Question 1

What are the 3 causes / categories of syncope?

Answer 1

1. Reflex syncope / “vasovagal”
2. Orthostatic hypotension
3. Cardiogenic syncope

Question 2

What types of seizures are there?

Answer 2

1. Focal / “partial”
   
   1. without impairement of consciousness “simple partial”
   2. with impairement of consciousness “complex partial”
2. Generalized
   
   • Tonic-clonic “grand mal”
   • Abscence seizures “petit mal”
   • Myoclonic
   • Atonic
   • Infantile spasms

Question 3

What can look like epilepsy but isn’t?

Answer 3

1. Syncope (various kinds)
2. Non-epileptic attack disorder
   
   • Requires psychotherapy
   • Characteristic pelvic thrusting
   • Slumping attack (looks like syncope)
   • Lack of post-ictal confusion (sometimes, not always)
   • See later card

Question 4

What is the definition of syncope?

Answer 4

• Loss of consciousness
• Which is transient
• And caused by global hypoperfusion (as opposed to focal e.g. TIA)
  
  • Rapid onset
  • Short duration
  • Spontaneous / complete recovery

Question 5

What might a patient experience before an episode of syncope?

Answer 5

• There may be a trigger
  
  • seeing blood (vasovagal)
  • tight shirt collar (carotid sinus)
  • post-exercise (situational)
  • position change (orthostatic hypotension)
• Prodromal symptoms / warnings e.g. in vasovagal syncope:
  
  • visual changes
    
    • loss
    • dimming
  • sweating
  • light-headedness
  • tinnitus
  • nausea
  • limb weakness
• Can be remembered as 3 Ps: Position, provoking, prodrome

Question 6

What characteristics do patients with syncope exhibit during an episode?

Answer 6

• Motor: flaccidity (hypoperfusion) or jerking limbs
• Duration: generally less than a minute / <30 seconds
• Colour: patients can go blue (suggesting cardiogenic cause) or pale

Question 7

What happens to patients after an episode of syncope?

Answer 7

• Full recovery in under a minute (in seizures there is often post-ictal confusion)
• May have relieving factors e.g. orthostatic hypotension; lying back down

Question 8

What are the 3 types of reflex / neurally mediated syncope?

What should you ask about?

What investigations are there to differentiate?

Answer 8

1. Vasovagal
   
   • ‘simple faint’
   • most common type of syncope
   • common in young people
   • often after an emotional response
     
     • fear, anxiety or disgust
   • may also happen due to prolonged standing.
2. Situational
   
   • syncope occurs consistently after a specific trigger​ e.g:
     
     • Post-micturition (the most common
     • Post-cough
     • Post-swallow
     • Post-defecation
     • Post-prandial
     • Post-exercise (note - during exercise is more alarming for cardiac cause)
3. Carotid sinus
   
   • syncope after mechanical manipulation of the carotid sinus
   • can happen accidentally whilst shaving, wearing a tight shirt collar or even head movement

Ask about:

• triggers
• warning symptoms
• position

Investigate with

• full history
• a tilt-table test
• lying - standing BP
• Carotid sinus massage (requires specialist!!)

Question 9

What is orthostatic hypotension?

What should you ask about?

What are the investigations for it?

Answer 9

• Unsteadiness or LOC on standing from lying in those with inadequate vasomotor reflexes.
• It is defined as a fall in systolic BP of 20mmHg+ or a fall of diastolic BP by 10mmHg+ when an individual assumes a standing position
• or a similar fall in BP within 3 minutes of upright tilt-table testing to at least 60°

Ask about:

• warning symptoms / prodrome (may be prolonged in delayed postural syncope - a drop in BP that occurs after 3 minutes not at once)
• position
• drug history
  
  • diuretics
  • alcohol
  • TCA
  • anti-hypertensive medications
  • anti-psychotics
• cause for hypovolaemia (check GI bleed)
• PMH
  
  • DM
  • uraemia
  • spinal cord lesions

Investigate with

• a tilt-table test
• lying - standing BP

Question 10

What are the 4 main causes of orthostatic hypotension?

Answer 10

1. Secondary to drugs
   
   • diuretics
   • alcohol
   • TCA
   • anti-hypertensive medications
   • anti-psychotics
2. Hypovolaemia
   
   • check sinister underlying cause e.g. GI bleed
3. Primary ANS failure
   
   • PD
   • LB Dementia
4. Secondary ANS failure
   
   • DM
   • Uraemia
   • Spinal cord lesions

Question 11

What are the cardiac causes of syncope?

Answer 11

1. Arrythmias
   
   1. Bradyarrythmias (more likely)
      
      • sick sinus syndrome
      • 2nd degree heart block
      • 3rd degree heart block
   2. Tachyarrythmias
      
      • SVT
        
        • Atrial flutter
        • Atrial fibrillation
        • Junctional
      • Ventricular (most likely out of the tachyarrythmias)
2. Structural ie outflow tract obstruction
   
   • Valvular (AS)
   • Cardiomyopathy (HOCM)
   • Cardiac mass (atrial myxoma)
   • Pericardial disease (constrictive pericarditis)
   • Non-cardiac causes
     
     • PE
     • Aortic dissection

Question 12

What questions should you ask if you suspect cardiac cause of syncope?

Answer 12

• FH of sudden death. Omitting this may miss a potentially fatal disease such as a familial channelopathy (e.g. long QT syndrome, Brugada syndrome) or cardiomyopathy (e.g. hypertrophic cardiomyopathy) which requires treatment
• Cardiac symptoms (breathlessness, chest pain, oedema)
• Prodrome (lack of this in cardiogenic syncope)
• Onset around exercise (during is more worrying)
• PMH of any heart problems, MI, pacemakers
• DH including diuretics

Question 13

What investigations should be done for a patient with suspected cardiogenic syncope?

Answer 13

1. ECG – looking for:
   
   • Ischaemic heart disease – pathological q-waves
   • Long QT interval
   • Wolff-Parkinson-White syndrome
2. Longer term ECG monitoring- to capture an association between syncope and the arrhythmia (this is the only way to definitively diagnose arrhythmic syncope)
   
   • Ambulatory ECG monitoring
   • External and implantable loop recorders
3. Echocardiography – looking for:
   
   • Heart failure
   • Cardiomyopathies
   • Valvular disease
   • Non-cardiac disease – e.g. pulmonary hypertension

Question 14

An absence of prodromal symptoms makes you more likely to consider this as a cause of TLoC

Answer 14

cardiogenic syncope

Question 15

What are the 5 Ps and Cs to remember questions in a syncope vs seizure history?

Answer 15

5 Ps:

• Precipitant (vasovagal)
• Prodrome (orthostatic, vasovagal, absence of → cardiogenic)
• Position (orthostatic)
• Palpitations (cardiogenic)
• Post-event phenomena (confusion/disorientation is more common after epileptic seizures)

5 Cs

• Colour (blue is more likely transient loss of respiratory muscle action in a tonic seizure, pale more likely systemic hypoperfusion ie syncope)
• Convulsions (happens in both syncope and seizures but tonic phase is characteristic)
• Continence (incontinence is more likely in seizures)
• Cardiac problems (points to cardiogenic syncope)
• Cardiac death family history (cardiogenic syncope)

Question 16

What kind of prodromal symptoms are more likely before an epileptic fit?

Answer 16

Most commonly found in focal (partial) seizures without loss of consciousness (simple):

• déjà vu
• strange smells
• strange tastes
• strange feeling
• intense joy / fear
• tingling in arms and legs
• rising feeling in the belly

Question 17

What defines a focal seizure without loss of consciousness/awareness?

“simple partial”

Answer 17

• Awareness is unimpaired
• Focal symptoms e.g.
  
  • stiffness / twitcing in limbs
  • rising in belly
  • deja vu
  • strange smells
  • intense emotions
  • localising features to certain lobes (see separate card)
• no post-ictal symptoms
• can spread to become generalised (which is then called secondary tonic-clonic)
  
  • therefore, these seizures are sometimes called ‘warnings’ or ‘auras’

Question 18

What defines a focal seizure with loss of consciousness/awareness?

“complex partial”

Answer 18

• Patient has a loss of awareness +/- consciousness
  
  • e.g. they may have their eyes open but be unresponsive
• Can follow“simple” focal seizure
• Most commonly the temporal lobe
  
  • post-ictal confusion makes temporal involvement more likely
• Random body movements, characteristically:
  
  • lip-smacking
  • rubbing hands
  • random noises
  • fiddling
  • picking clothes
  • moving arms
• Patient will have no memory of it

Question 19

What defines a tonic-clonic seizure?

“grand-mal”

Answer 19

• It is a generalized motor seizure: electronic activity is spread all over the brain, and movements are involved
• Loss of consciousness
• +/- Tonic phase - during which patient goes stiff / rigid / may fall to floor
• +/- Clonic phase - during which
  
  • patient’s limbs jerk
  • incontinence
  • tongue biting
  • difficulty breathing
    
    • can make them blue
• Post-ictal drowsiness / confusion

Question 20

What defines an absence seizure?

“petit-mal”

Answer 20

• Generalised seizure type
• Childhood onset
• Presents with
  
  • “Day-dreaming look”
  • eylid fluttering
  • pausing in the middle of speaking, then picking up where they left off
• Usually short duration (10secs)

Question 21

What defines a myoclonic seizure?

Answer 21

• Generalized seizure type
• “movement” of “muscle”:
  
  • a spasm or twitch or jerk
  • one part of body or whole body
• Often soon after waking
• Conscious / aware throughout
• Often very short duration (5 secs)

Question 22

What are some provoking causes for seizures?

(the 1/3 that aren’t idiopathic!)

Answer 22

• Consider NEAD (non-epileptic attack disorder)
• Structural:
  
  • Stroke
  • SOL
  • Cortical scarring
  • febrile convulsions
• Provoking causes:
  
  • Withdrawal
    
    • alcohol
    • benzos
  • Infection
    
    • meningitis
    • encephalitis
  • Raised ICP
  • Drugs
    
    • Cocaine
    • TCAs
  • haemorrhage
  • liver disease
• Metabolic:
  
  • Hypoxia
  • ↑↓Na+
  • ↓Ca2+
  • ↓glucose

Question 23

What are some localizing features of focal seizures?

ie. which part of the brain will produce which symptoms?

Answer 23

Temporal Lobe (most common in focal seizures):

• automatisms:
  
  • Primative oral - lip smacking, random noises
  • Primative manual - grabbing, hand rubbing, fiddling, picking at clothes, moving arms
• dysphasia
• hallucinations
  
  • smell
  • taste
  • sound
• deja vu / jamias vu
• emotional disturbance
  
  • anger
  • de-realisation
  • anxiety
  • panic / terror

Frontal Lobe:

• subtle behaviour changes
• dysphagia / speech arrest
• Motor:
  
  • peddling
  • post-ictal Todd’s palsy = weakness 24hrs after seizure

Parietal Lobe:

• Sensory disturbances
  
  • tingling
  • numbness
  • pain (rare
• Motor (if spread to pre-central gyrus)

Occipital Lobe:

• Visual phenomena
  
  • stripes
  • dots
  • flashes

Question 24

What is first-line AEDs for epilepsy in a woman of childbearing age?

Answer 24

Lamotrigine

Question 25

What are 5 common AEDs and what types of seizures are they used in?

Answer 25

• Sodium valproate
  
  • first line for generalised/absence seizures
• Carbemazepine, first line for:
  
  • focal seizures with + w/out secondary generalisation
  • primary generalised seizures
• Lamotrigine
  
  • Seizure control in pregnancy / women of childbearing age
• Phenytoin
  
  • status epilepticus where benzos aren’t working
  • last-line seizure frequency control (others are preferred)
• Topiramate
  
  • generalised or focal

Question 26

What are the common counselling points for carbamazepine?

Answer 26

• Aim: reduce seizure frequency
• Warn:
  
  • signs of severe hypersensitivity:
    
    • Blood toxicity: rashes, bruises, bleeding, ulcers, raised temperature
    • Liver toxicity: reduced appetite / abdo pain
  • contraception:
    
    • Some types may reduce the effectiveness of various hormonal contracepton types e.g. implant, patch, progestogen-only pill (the mini pill)
    • an alternative contraceptive method is recommended.
  • pregnancy: not advised

Question 27

What are the common counselling points for sodium valproate?

Answer 27

• Aim: reduce frequency of seizures
• Side effects: GI:
  
  • tummy upset
  • indigestion
  • can be improved by taking it with food
  • seek urgent medical attention if hypersensitivity symptoms occur (see carbamazepine)
• Pregnancy: AVOID, see specialist (+folic acid)

Question 28

What are the adverse effects of AEDs?

Answer 28

• Rare and serious:
  
  • Rash (Steven Johnson Syndrome - flu like symptoms progress to blistering red / purple rash) carbemazepine, phenytoin
  • Bone marrow suppression carbemazepine
  • Hepatic toxicity valproate
• Neurotoxic
  
  • Dizziness
  • Incoordination
  • Drowsiness etc.
• Metabolic
  
  • Weight gain valproate
  • Weight loss topiramate
• Reproductive
  
  • Teratogenic
  • POS
  • Erectile dysfunction

Question 29

Which AEDs are tetrogenic?

Answer 29

Sodium valproate, topiramate and carbamazepine

Question 30

What is NEAD?

Answer 30

Non-Epileptic Attack Disorder

• episodic disturbances of normal function and control that superficially resemble epileptic attacks but are not caused by epileptic activity in the brain and are thought to have a psychological basis
• Treatment is not EADs, but psychotherapy

Question 31

What are the defining features of an attack of NEAD?

Answer 31

• Eyes closed, difficult to open
• Can be aware of what’s happening but may be unable to respond
• Timing:
  
  • Attack tends to last longer
  • Different lengths each time - epileptic seizures are stereotyped, non-epileptic seizures are less predictable
• Movements:
  
  • Head moves from side to side
  • Pelvic thrusting
  • Or, slumping (looks like syncope)
• Otherwise can be very similar to epilepsy, requires specialist review

Question 32

What are some risk factors for developing epilepsy?

Answer 32

• Febrile convulsions as a child
• FH of epilepsy
• Developmental problems
• Low birth weight

Question 33

What are some common triggers for epilepsy?

Answer 33

• Not taking epilepsy medicine as prescribed.
• Feeling tired and not sleeping well.
• Stress.
• Alcohol and recreational drugs.
• Flashing or flickering lights.
• Monthly periods.
• Missing meals.
• Having an illness which causes a high temperature

Question 34

How should you manage a patient with new-onset seizures?

Answer 34

• Refer to a neurologist for a consultation within 2 weeks
  
  • referral letter should include a detailed description of the seizure from a first-hand witness (ideally)
• Advise patient not to drive and to avoid potentially dangerous work or leisure activities.
  
  • In particular, they should avoid swimming, and take care when bathing to avoid the risk of drowning (shower over bath)
• Family: if they have another seizure:
  
  • How to manage it
  • Record details of it
  • Go to GP

Question 35

1. When should you be worried about status epilepticus?
2. What should the patient’s family do?

Answer 35

1. When a seizure has gone on for 5 minutes or more, or they have had 3 in an hour.
2. Call 999 and get patient to hospital. First aid for seizure.

Question 36

What are the DVLA guidelines on driving with epilepsy?

Answer 36

• For normal drivers, you must tell the DVLA
• Not drive for 12 months after your last seizure

Question 37

Name some differentials for tLOC with jerking / twitching

Answer 37

1. Epilepsy
2. NEAD
3. Syncope
4. Metabolic
   
   • sepsis
   • type 2 respiratory failure
   • hypoglycaemia
5. Drug-related
   
   • withdrawal e.g. alcohol
   • overdose
6. Encephalopathy
   
   • e.g. benzo induced coma
   • encephalitis
   • malignant hypertension
   • eclampsia

Question 38

What investigations are important in assessing a seizure patient to rule out organic caused of seizure?

Answer 38

1. History and Collateral History
2. FBC (evidence of systemic or CNS infection
3. Blood glucose (hypoglycaemia)
4. Electrolyte panel (low or high Na+, low Ca2+, uraemia)
5. EEG (but false negatives and positives)
6. CT / MRI head if SOL supsected