Loss of Consciousness Seizures/epilepsy Flashcards
First approach to the unconscious patient
- Is it safe for me to intervene
- How much time do I have?
A-Airways
B-Breathing
C-circulation - DEFG (dont ever forget glucose)
- Where is the problem?
- GCS - Bloods U&es, ABGs, LFTS
Causes
Faints
Fits
Funny Turns
Faints
lack of blood to the brain
vasovagal due to activation of parasympathetic nerve sstem
Fits
electrical discharge/ seizure
Non-epileptic events
(psuedo seizures)
People whos reaction to life events (metabolic, psychological, trauma) have lead to a dissociation/ episode of epileptic event with or without movement
What helps differentiate Blackouts ?
- Patient (before, during, after)
- Eye witness (before, during, after)
- Other questions (risk factors, other seizures)
Features of syncope
Trigger- commonly
Prodrome- always, reduced BP, RR and clammy
Onset-gradual (over minutes) Duration- 1-30 seconds Convulsion- Brief, mild twitches Incontinence- uncommon
Lateral tongue bite- very rare Colour- Very pale
Post Ictal confusion- rare
Recovery- rapid. Fall- Slump. May bite the tip of the tongue
Features of seizure
- Trigger- rare (light, HV)
- Prodrome – common (deja vu, foreboding, lightheaded)
- Onset- usually sudden
- Duration- 1-3 minutes ( the longer the more likely it will be a stroke)
- Convulsive jerks -> tonic clonic seizures, prolonged
- Incontinence- common
- Lateral tongue biting- common
- Colour change-pale, red and blue (flushed)
- Post ictal confusion- common (disorientated in ambulance)
- Recoveryslow
Defnition of Seizure
Sustained and synchronised electrical discharge in the brain causing signs and symptoms
Definition of epilepsy
Tendency to have recurrent unprovoked seizures >1
Classification of seizures
Focal or Generalized
Focal /partial seizure definition
Focal onset, with features referable to part of one hemisphere (motor, sensory & psychological phenomenon & loss of awareness)
Generalized seizure definition
Simultaneous onset of electrical discharge throughout cortex, with no localizing features refereable to only one hemisphere
Types of generalized seizures
Absence seizures- Brief (,10s) pauses e.g suddenly stops talking in mid-sentence then carries on where left off
Tonic-clonic seizures : limbs stiffen (tonic) then jerk (clonic). May have one without the other. Post-ictal confusion/drowsiness LOSS OF CONSCIOUSNESS
Myoclonic seizures: sudden jerk of a limb, face or trunk. Patient may be thrown suddenly to the ground.
Clinical approach to the first seizure
- Clinical diagnosis (get the history)
- Investigations
- ECG-> cardiac cause
- EEG (electroencephalogram)
- MRI- Everyone - Risk of recurrence
- provoked ( 3-10%)
- Un-provoked - 30-50%
Causes of epilepsy
2/3 are idiopathic
Structural: cortical scarring (head injury), developmental, space occupying lesion, stroke
Others: TB, sarcoidosis
Non-epileptic causes: trauma, stroke, alcohol
Metabolic disturbances: Hypoxia, liver disease, infection, drugs
Diagnosis
- Are these really seizures? - description from eye witness and patient?
- What type of seizure is it?
- Any triggers ?
Status epilepticus definition
A seizure that will carry on for five minutes or 15 minutes without response to treatment
Treatment of status epilepticus
- Is it a seizure?
- Immediate management - ABC
- If > 5 minutes
a. BG, Oximetry, Bloods, Clotting symstems, AED levels
b. Inital therapy
- IV Benzodiazepine if still over 5 minutes then repeat benzodiasepine
- treat potential causes (IV glucose for hypoglycaemia, IV thiamine if alchol abuse) - Still continues for further 5 minutes
- IV dosing with Phenytoin or valproate - Seziure still continues then
- admitt to ITU
- Monitor with EEG
- Sedation with general anesthetic
Long-term Seizure prevention treatment
recurrence risk after 1 seizure =
Low risk = no indication for treatment
high risk= If serious head injury or develomental problem then requirement for treatment
Reccurence after 2 seizures
= 55-60%
- once fulfilled diagnosis then treatment indicated
Types of seizure prevention drugs
- Reduce pre-synaptic excitability
a. Voltage-gated Na+ channel antagonist (carbamazepine, lamotrigrine)
b. Voltage-gated K+ channel agonist (retigabine) - Stops neurotransmitter release
a. SV2A vesicle antagonist (levetiracetam)
b. Voltage-gated Ca2+ channel antagonist (pregablin and gabapentin) - GABA-ergic system agonists
a. GABA metabolism inhibitor (valproate, vigabatrin)
b. GABA transporter antagonist (tiagabine)
- Reduces post-synaptic excitability
a. GABA receptor agonist (benzodiazepines)
b. AMPA and NMDA receptor antagonist
