Epilepsy Flashcards
What is epilepsy?
More than 2 seizures
What is a seizure?
AKA Ictus. Paroxysmal synchronised cortical electrical discharges
What is pathophysiology of seizure?
Result from imbalance in the inhibitory and excitatory currents (sodium and potassium channels), or neurotransmission (glutamate or GABA NEUROTRANSMITTERS) in the brain.
What are the two categories of epilepsy?
GENERALISED: abnormal neurotransmission in the whole brain which all results in loss of consciousness; PARTIAL/FOCAL: abnormal neurotransmission occurs in small part of the brain.
What are the types of generalised epilepsy? (x5)
- Tonic-clonic – unconscious, tonic phase followed by clonic phase
- Absence – Short-lived. Characterised by zoning out (still considered loss of consciousness) OR jerking (with loss of consciousness).
- Myoclonic – exaggerated twitch of area of the body.
- Atonic – short-lived loss of muscle tone which results in individual falling over flat suddenly.
- Tonic seizures – sudden stiffness for around 20 seconds, followed by confusion and tiredness
What are the types of partial epilepsy? (x3)
- Simple – uncontrolled twitched of one part of the body – no loss of consciousness.
- Complex – affects the temporal lobe and most difficult to treat. Results in loss of awareness, confusion, and unusual behaviours and gestures.
- Secondary generalised – generalised seizures develop from a partial one.
What is the aetiology of epilepsy?
- Idiopathic in most cases
- PRIMARY: idiopathic generalised epilepsy, temporal lobe epilepsy, juvenile myoclonic epilepsy
- SECONDARY (known as symptomatic epilepsy): tumour, infection (meningitis, encephalitis, abscess), inflammation (vasculitis), toxic/metabolic (ion imbalances, liver failure, low blood sugar), drugs (including withdrawal), vascular (stroke), neurodegenerative (such as Alzheimer’s), malignant HTN, trauma, flashing lights, sleep deprivation
What is the common aetiology of focal seizure?
Brain lesions
What is the epidemiology of epilepsy? (x2)
Peak age of onset is early childhood or elderly
How should an epilepsy history be taken? (x7)
- Rapidity of onset?
- Duration of episode?
- Alteration of consciousness?
- Any tongue-biting or incontinence?
- Any rhythmic synchronous limb jerking?
- Any post-ictal period?
- Drug history
What are the signs and symptoms of focal seizures: Frontal lobe focal motor? Temporal lobe? Frontal lobe complex partial?
- FLFM: motor convulsions that may demonstrate Jacksonian march (spasm spreading from mouth or digit). There may be post-ictal flaccid weakness (called Todd’s paralysis)
- TL: aura (visceral and psychic symptoms such as fear or deja-vu sensation), and hallucinations (olfactory, gustatory (taste))
- FLCP: loss of consciousness with associated automatisms (performance of actions without thought) and rapid recovery
What is a convulsion?
Sudden, violent, involuntary movements
What are the signs and symptoms of each generalised seizure: Tonic-clonic? Absence? Myoclonic? Atonic? Tonic?
- Tonic-clonic: vague symptoms before such as irritability, followed by tonic phase (generalised muscle spasm), followed by clonic phase (repetitive synchronous jerks) and associated faecal/urinary incontinence, tongue biting and unconsciousness. After, there is impaired consciousness, lethargy, confusion, headache, back pain and stiffness
- Absence: loss of consciousness but maintained posture (patient stops talking and stares blank), blinking or rolling up of eyes with other repetitive motor actions such as chewing. No post-ictal phase
- Myoclonic: exaggerated twitch of an area of the body
- Atonic: short-lived loss of muscle tone which results in individual falling over flat suddenly
- Tonic: sudden stiffness for around 20 seconds, followed by confusion and tiredness
What is status epilepticus?
A life-threatening neurological condition defined as 5 or more minutes of either continuous seizure activity or repetitive seizures without regaining consciousness.
What is non-convulsive status epilepticus?
Generalised epilepsy characterised by acute confused state, often fluctuating, and difficult to distinguish from dementia.
What are the investigations for epilepsy? (x4)
- BLOOD: establish aetiology – electrolytes, glucose, ABG, toxicology. PROLACTIN is a serum marker of seizure
- EEG: helps to confirm diagnosis and assists in classification
- CT/MRI: for structural, space-occupying and vascular lesions
- LP: for aetiology
How is status epilepticus managed? (x5)
- Protect airway
- Check glucose and give if hypoglycaemic
- IV lorazepam or diazepam (repeat once after 15 minutes if needed)
- Recurrence or failure to respond: IV phenytoin under ECG monitoring, or IV phenobarbitone, levetiracetam or sodium valproate
- Failure to respond: general anaesthesia with intubation
What must happen after anticonvulsant administration?
Should check plasma levels
What is the indication for pharmacological management of seizures?
More than 2 unprovoked episodes
How are epileptic seizures treated?
- FOCAL: lamotrigine and carbamazepine
- GENERAL: sodium valproate treats all. Can also use carbamazepine and lamotrigine (tonic-clonic), ethosuximide (absence), levetiracetam and topiramate (myoclonic), diazepam (status epilepticus) phenytoin, clobazam (BDZ), gabapentin, vigabatrin and more
What patient education is there for epilepsy? (x5)
Avoid triggers like alcohol, encourage seizure diaries, recommend supervision in swimming/climbing, driving permitted if seizure free for 6 months, women of child-bearing age should be counselled on teratogenic effects of AEDs (anti-epileptic drugs) and should take folate to limit risk.
Drug interactions of AEDs?
Enzyme-inducing AEDs can limit the effectiveness of OCP
What surgical management is there for epilepsy? Indication?
Removal of definable epileptogenic focus (determined from detailed EEG, intracortical recordings, ictal SPECT (compares blood flow during and in-between seizures on MRI)). Indicated for refractory epilepsy.
What are the complications of epilepsy? (x3)
Fractures, behavioural problems, and sudden death in epilepsy (SUDEP)
What is the prognosis of epilepsy?
50% remission at 1 year.
