Epilepsy Flashcards
What is the approach to the fallen?
History
Patient; before, during and after
Eye witness; before, during and after
What are the important features to an epilepsy history?
Onset; what were they doing, light headedness or other syncopal symptoms, what did they look like (pallor, breathing, posturing of limbs, head turning)
Event itself;
Type of movements; tonic phase, clonic movements, corpopedal spasm, rigor, responsiveness and awareness throughout
Afterwards; speed of recovery, sleepiness/disorientation, deficits
What is common of a frontal lobe tonic clonic seizure?
Right hand moves upwards
Head turns to the right
Stiff movements
Clonus
What is important to do if you suspect syncope over epilepsy?
CV exam
L+S BP
What are common drugs which can precipitate epilepsy?
Theophylinne Amphetamines Tramadol Antibiotics; penicillins, cephalosporins, quinolones Antidepressants Anticholinergics Antiemetics; prochlorperazine Cocaine Opioids; diamorphine, pethidine
What investigation is the MOST important when working someone up for a seizure?
ECG; prolonged QT syndrome can trigger a generalised tonic clonic seizure and is LIFE THREATNING
Who gets a CT scan acutely?
Clinical or radiological skull#
Deteriorating GCS
Focal signs; stroke or bleed
Head injury with seizure
Failure to be GCS 14/15 4 hours after arrival
Suggestion of other pathology eg. SAH or stroke
When are EEGs helpful?
Classification of epilepsy
Confirmation of non-epileptic attacks
Surgical eval for epilepsy surgery
Confirmation of non-convulsive status
Can you diagnose epilepsy with an EEG?
NO
What are conditions that can “mimic” epilepsy?
Syncope Non-epileptic attack disorder (pseudoseizures, psychogenic non-epileptic attacks) Panic attacks/ hyperventilation attacks Sleep phenomena Hypoglycamia; ALWAYS DO A BG
What are the laws around driving and epilepsy?
1st seizure; 6 months or if HGV/PCV 5 years
Epilepsy; 1 year seizure free or 3 years seizure free if nocturnal epilepsy. If HGV/PCV; 10 years seizure free
What is a good description of myoclonus?
Clumsy and jerky in the morning
What is epilepsy?
A tendency to recurrent, usually spontaneous, epileptic seizures
What is an epileptic seizure?
Abnormal synchronisation of neuronal activity; usually excitatory with high frequency action potentials
Can be focal or generalised
Why do epileptic seizures happen?
Too little inhibition/ too much excitation
Changes in:
Cell number/type
Connectivity
Synaptic function
Voltage gated ion channel function
Genetic, acquired brain, metabolic (hypoglycaemia), toxic
What is SUDEP?
Sudden Unexplained Death in Epilepsy; seizure with subsequent cardiac arrest
What is a focal seizure?
Brain abnormal; stroke, haemorrhage, demyelination, tumour which will irritate the surrounding area resulting in abnormal discharge of electricity
If it hits a pathway; it will become generalised SO you can get a focal seizure with secondary generalisation
What is a generalised seizure?
A seizure that begins on a pathway such as the corticothalamic circuit and therefore every time a person has a seizure it will be generalised
This differs from focal seizures where you can have purely focal seizures which secondarily generalise
What is the difference between simple and complex partial/focal seizures?
Simple; without impaired consciousness
Complex; with impaired consciousness
What are the different types of generalised seizures?
Absence Myoclonic Atonic Tonic Tonic clonic
Which seizures can cause a loss of consciousness?
Complex partial seizure Generalised absence seizure
What motor symptoms can be involved in partial seizures?
Rhythmic jerking Posturing Head and eye deviation Cycling Automatisms (plucking) Vocalisation
What sensory symptoms an be involved in partial seizures?
Somatosensory Olfactory Gustatory Visual Auditory
What psychic symptoms can be involved in partial seizures?
Memories Deja vu Jamais Vu Depersonalisation Aphasia Complex visual hallucinations
Who is likely to get generalised seizures?
Genetic predisposition
Present in childhood and adolescence
What EEG pattern will generalised seizures show?
Spike wave pattern
What is the treatment of choice for primary generalized epilepsy?
Sodium valproate
What is the alternative treatment for primary generalized seizures for women of child bearing age?
Lamotrigine
Describe juvenile myoclonic epilepsy
Early morning jerks
Generalised seizures
Risk factors; sleep deprivation, flashing lights
What are some common side effects of sodium valproate?
HIGHLY TERATOGENIC
Weight gain
Hair loss
What is the treatment for focal onset epilepsy?
Identify the underlying structural cause
1st line: carbamazepine or lamotrigine
What is the most common type of focal onset epilepsy?
Complex partial seizures with hippocampal sclerosis
What is the most common type of primary generalised epilepsy?
Juvenile myoclonic epilepsy
What is a very important side effect of carbamazepine?
Enzyme inducing in the liver; reduced the efficacy of the OCP and morning after pill
What channel will carbamazepine, lamotrigine and phenytoin inhibit?
Voltage gated sodium channel
Reduced pre-synaptic excitability
What channel will levetiracetam inhibit?
SV2A which is required for the release of neurotransmitter at the presynaptic terminal
What channel will pregabalin and gabapentin inhibit?
Voltage gated Ca 2+ channels in the presynaptic terminal
What will benzos and barbiturates target in the neurone?
GABA receptor which reduced neuronal activity
What will sodium valproate target?
Enhances GABA synthesis
Why do you need to be careful when co-prescribing sodium valproate and lamotrigine?
Sodium valproate inhibits the metabolism of lamotrigine so cana get a toxic dose BUT they work synergistically well together, just need to prescribe a lower dose of lamotrigine
Treatment for partial seziures
INITIAL:
Carbamazepine
Lamotrigine
What is the treatment for absence generalised seizures?
Sodium valproate
Ethosuximide
What is the treatment for myoclonic seizures?
Sodium valproate
Levetiracetam
Clonazepam
What is the treatment for atonic, tonic and tonic clonic seizures?
Sodium valproate
Levetiracetam
Topiramate
Lamotrigine
When is phenytoin used?
Acute management ONLY as rapid loading dose possible
Should you prescribe carbamazepine in primary generalised seizures?
NO; makes MUCH worse. This is why you NEED to determine the cause for the epilepsy
What condition is topiramate commonly used in?
Idiopathic Intracranial Hypertension; causes weight loss
Why does lamotrigine take a long time to titrate up?
Can cause SJS; start at a very low dose then build up
If there are ANY rashes, STOP immediately
When should you prescribe anticonvulsants?
If the patient has epilepsy
If there has been a single seizure but a high risk of recurrence
Which anticonvulsants induce hepatic enzymes?
EXAM QUESTION
Carbamazepine Oxcarbazepine Phenobarbital Phenytoin Primidone Topiramate
Why is it important to know which anticonvulsants induce hepatic enzymes?
EXAM QUESTIONS
Can alter the efficacy of OCP and emergency contraception - you MUST get the higher dose
SHOULDN’T use POP; not effective
What should be given to women preconception who have epilepsy?
3 months preconception:
High dose folic acid
Vitamin K
What is status epilepticus?
Recurrent epileptic seizures without full recovery of consciousness
Continuous seizure activity lasting more than 10-30 mins
What are the different types of status epilepticus?
Generalised convulsive status epilepticus
Nonconvulsive status; conscious but in altered state (Use EEG for this)
Epilepsia partialis continus (continual focal seizures, consciousness preserved)
What are precipitants of status?
Severe metabolic disorders; hyponatraemia, pyridoxine deficiency Infection Head trauma SAH Abrupt withdrawal of anticonvulsants Treating absence seizures with CBZ
What can status cause?
Respiratory insufficiency and hypoxia Hypotension Hyperthermia Rhabdo DEATH
What occurs after 30-60 mins of status?
Peripheral metabolic effects due to SUCH high demand
What occurs after 60 mins - 8 hours of status?
Multiorgan failure
What occurs after 8 hours of status?
Central effects
What is the order of drugs you would give in status?
EXAM QUESTION
10mg benzo then repeat after 5 mins. ONLY GIVE 2 DOSES OF BENZO
THEN
Phenytoin, sodium valproate and levetiracetam
What should you do if phenytoin/ sodium valproate/ levetiracetam doesn’t work?
Phone ICU as they need to be sedated with propofol to flatten EEG for around 48 hours`
What should be given if there is ANY suggestion of a hypo in a patient in status?
50m 50% glucose
What should be given if there is ANY suggestion of alcoholism or nutritional deficiency in a patient in status?
IV thiamine
What are the different types of benzos?
Lorazepam 4mg IV (long duration
Diazepam 10-20mg IV
What should you do if you don’t have IV access in a patient in status?
Diazepam or midazolam PR
What are the dosages of phenytoin and phenobarb given in status?
Phenytoin i18mg/kg IV <50mg/min with ECG monitoring
Phenobarb 15mg/kg IV 100mg/min
What is important to do surrounding a patients normal anticonvulsant medication when they are in status?
Give normal dosages down NG tube as abrupt withdrawal of anticonvulsant medication is a trigger of status epilepticus
