Epilepsy Flashcards
In a patient with suspected epilepsy what three stages are important to ask about in the history?
- onset
- event
- afterwards
What are important factors when asking about onset?
Environment - flashing lights, light head, syncope, what did the patient look like (pallor, posture, breathing)
What are important factors when asking about the event?
Tonic phase, clonic movements, corpopedal spasms, rigor, responsiveness, awareness
What are important factors when asking about after the event?
Speed of recovery, sleepiness/disorientation, deficits
State the risk factors for epilepsy
Birth problems, developmental issues, seizures in the past, head injury, family history, drugs, alcohol
If a patient presents with collapse what must always be done and why?
ECG - long QT
When is a CT indicated in a patient who has had a seizure?
- skull fracture
- deteriorating GCS
- focal signs
- head injury with seizure
- failure of GCS to be 15/15 4 hours after arrival
- suggestion of other pathology e.g subarachnoid haemorrhage
When is an EEG useful?
- Helpful when determining whether someone is in non-convulsive status or septic encephalopathy
- Non-epileptic attacks
- Epilepsy surgery to determine location
- Determining the type of epilepsy
State some differential diagnoses for epilepsy
- syncope
- non-epileptic attack
- panic attack
- sleep phenomena
- TIA
- migraine
- hypoglycaemia
What are the driving regulations after a patient has their first seizure?
Car - 6 months
HCV/PCV - 5 years
If you have nocturnal seizures how long until you can drive?
3 years
How long off medications do you need to be to drive an HCG/PCV?
10 years
Define epilepsy
A tendency to recurrent, usually spontaneous epileptic seizures
Define epileptic seizure
Abnormal discharge of electrical signals in the brain
What factors contribute to the pathology of epilepsy?
Genetic, acquired brain injury, metabolic disease, toxic and environmental factors
Name the two key types of epilepsy
Focal
Generalised
Describe focal epilepsy
Part of the brain does not work properly due to structural abnormality - seizure focus. This irritates the surrounding area and can cause a seizure
How can focal epilepsy lead to a generalised seizure?
Cortical networks may be involved and therefore the irritation can spread throughout the brain
Define seizure
Abnormal discharge of electrical activity in the brain
What are the three focal symptoms?
Motor - jerking, posturing, head and eye deviation
Sensory - olfactory, gustatory, visual, auditory
Psychic - déja vu, depersonalisation, jamais vu, aphasia, hallucinations
Name the five types of generalised seizure
- absence
- myoclonic
- atonic
- tonic
- tonic clonic
What types of generalised seizure can be due to focal epilepsy?
Tonic
Tonic clonic
Describe generalised epilepsy
Seizures happen on the cortical networks and cannot stay in the same place - they propagate around the brain
Who is usually affected by each type of epilepsy and why?
Generalised - young people, due to genetics
Focal - older people due to structural abnormality
What drugs can be used to treat primary generalised epilepsy?
Sodium valproate
Lamotrigine
What drugs can be used to treat focal onset epilepsy?
Carbamazepine
Lamotrigine
Why do sodium valproate and lamotrigine work well in combination?
As sodium valproate inhibits the metabolism of lamotrigine
What drugs are used to treat generalised absence seizures?
Sodium valproate
Ethosuximide
What drugs are used to treat generalised myoclonic seizures?
Sodium valproate
Leveliracetam
Clonazepam
What drugs are used to treat atonic, tonic, tonic-clonic seizures?
Sodium valproate
Levetiracetam
Topriamate
Lamotrigine
What is the problem with sodium valproate?
Teratogenic
How do anti-convulsants alter the efficacy of contraception?
By induction of hepatic enzymes
State the name for the most serious seizures
Status epilepticus
Describe status epilepticus
Recurrent epileptic seizures without full recovery of consciousness, lasting more than 30 minutes
After what amount of time of status epilepticus would a patient get treated?
10 mins
Name the three types of status epilepticus
Generalised convulsive (tonic-clonic)
Non-convulsive status
Epilepsia partialis continua
What can precipitate status epilepticus?
- severe metabolic disorders
- infection
- head trauma
- sub-arachnoid haemorrhage
- abrupt withdrawal of anti-convulsant
- treating absence seizures with carbamazepine
What happens in a non-convulsive status?
Conscious but altered state
Describe how generalised convulsive status can kill you
First 30 mins - aspirations
30mins -2 hours - hypoxia, hypotension, hyperthermia, excess demand for cerebral energy and poor substrate delivery
Longer term - glutamate release causes excitotoxicity and ultimately neuronal death
What drug is given if a patient has had status epilepticus for more than 10 mins?
Benzodiazepines - buccal midazalam, maximum of 2 doses as risk of respiratory distress
What anti-convulsant drugs can be given in status epilepticus?
Phenytoin
Levetiracetam
Sodium valproate
What non-anticonvulsant drugs may be needed in status?
Thiamine and glucose
In non-convulsive status what investigation is done?
EEG to rule of septic encephalopathy
Why are benzodiazepines given in non-convulsive status?
To treat central brain firing problems
What is an aura?
Epileptic seizure that happens in the sensory area of the brain - numbness, tingling, electric shocks
What happens in a visual aura?
Flashing, static, moving lights, occipital or temporal lobe involvement
Describe an autonomic aura
Similar to syncope - occurs in the temporal lobe
State three features of functional attacks
- Prominent motor activity
- Episodes of collapse with no movement
- Abreactive attacks - fear, gasping, hyperventilation
How long do functional attacks usually last?
10-20 mins
How can functional attacks be diagnosed?
EEG and video with provocation, linguistic analysis very matter of fact language
