Epilepsy I Flashcards
What are the important features of taking a history in a patient who has fallen down?
Get patient experience before, during and after event
Eye witness is critical = ask for demonstration of movements
What questions do you ask about the onset of someone falling?
What were they doing, environment, light headedness or syncope, pallor, breathing, posturing of limbs, head turning
What types of movements may someone exhibit when they fall down?
Tonic phase, clonic movements, corpopedal spasms, rigor
What are the important parts of the aftermath of a falling incident?
Speed of recovery, sleepiness, disorientation, deficits
What are the risk factors for epilepsy?
Birth and development, seizures in past (including febrile), head injury (especially loss of consciousness), drugs, family history
What is done in a seizure clinic?
Don’t examine patient in first visit = take history only
If diagnosis of syncope = CV examination and take lying and standing BP
What are high risk drugs for causing epilepsy?
Tramadol, prochloperazine, morphine and other opioids
What is the most important investigation to do in someone who has collasped?
ECG = must exclude long QT syndrome as it can present with syncopal seizures which mimic epilepsy
What imaging is done in clinic?
MRI = better than CT for imaging brain and doesn’t give dose of radiation
Which patients get a CT scan done acutely?
Skull fracture, deteriorating GCS, focal signs, head injury with seizures, failure of GCS to be 15 after 4hrs, suggestion of other pathology
What are the indications for doing an EEG?
To determine if someone is in non-convulsant status
To classify type of epilepsy
To confirm non-epileptic attacks
For surgical evaluation
Are EEGs always abnormal in epileptics?
No = EEG can be normal in epilepsy, and abnormal in non-epileptics
What are the differentials of epilepsy?
Syncope, panic attacks, TIA, hypoglycaemia, cataplexy, tonic spasm of MS, non-epileptic attack disorder, sleep phenomena, migraine, parasomnias, periodic paralysis
What are some features of seizure counselling?
Reassure patient = seizures don’t always mean epilepsy
Risk of recurrences and of sudden unexplained death in epilepsy (SUDEP)
What are the rules for driving with a history of seizures?
Seizures = must be free of seizure for 6 months or 5 years for HGV Epilepsy = clear for 1 year or 3 years during sleep, 10 years off medication for HGV
What safety advice is given to patients with seizures and epilepsy?
Avoid using deep far friers, baths and climbing ladders
Rock climbing and open water swimming not advised
What is epilepsy?
Tendancy to recurrent, usually spontaneous epileptic seizures
What causes epilepsy?
Abnormal synchronisation of neuronal activity = usually excitatory with high frequency AP, sometimes inhibitory
What occurs in epilepsy?
Interruption of normal brain activity = focally or generalised, usually brief (seconds-minutes)
What is the incidence of epilepsy?
Most common in infancy and old age
Occurs in 50-80/100,000
Mortality = 1/400 per annum, 1/100 in young people
What causes focal epilepsy?
Part of the brain is structurally abnormal = can cause both focal and generalised seizures (irritates cortical pathways)
What occurs in generalised epilepsy?
Cortical networks involved so only generalised seizures occur
What are the categories of focal deficits?
Motor, sensory and psychic
What are some motor focal deficits?
Rhythmic jerking, posturing, head and eye deviation, automatisms, vocalisations
What are some types of focal sensory deficits?
Olfactory, gustatory, somatosensory, visual, auditory
What are some focal psychic deficits?
Memory issues, deja vu, depersonalisation, aphasia, complex visual hallucinations
What are the kinds of generalised seizures?
Absence, myoclonic, atonic, tonic, tonic clonic
What is the epidemiology of generalised seizures?
Most are genetic
Present in childhood and adolescence
What are some features of primary generalised epilepsy?
Generalised spike wave abnormalities on EEG
Often presents in childhood or teens
What is the treatment for primary generalised epilepsy?
Sodium valporate is first line = teratogenic
Lamotrigine is second line
What is an example of a primary generalised epilepsy?
Juvenile myoclonic epilepsy = early morning jerks, generalised seizures, risk factors are sleep deprivation and flashing lights
What are some features of focal onset epilepsy?
Underlying structural cause
Onset at any age = more common with increasing age
Complex partial seizures with hippocampal sclerosis
How is focal onset epilepsy treated?
Carbamazepine or lamotrigine
How effective are anti-epileptic drugs?
55% are seizure free after starting monotherapy
85% have drug resistant epilepsy
What areas do anti-epileptic drugs target?
Pre-synaptic exitability and neurotransmitter release
The GABA system
What are the only two anti-epileptic drugs that can be used in combination?
Sodium valproate and lamotrigine
How are absences treated?
Sodium valproate or ethosuximide
How are myoclonic seizures treated?
Sodium valproate, levetiracetem or clonazepam
Lamotrigine may make it worse
How are atonic, tonic and tonic-clonic seizures treated?
Sodium valproate
What are some examples of anti-convulsants?
Phenytoin, sodium valproate, carbamazepine, lamotrigine, levetiracetam, topiramide, gabapentin/pregabalin
What is phenytoin used for?
Acute management only = emzyme inducer
What are some of the side effects of sodium valproate?
Weight gain, hair loss and fatigue
What are some features of carbamazepine?
Effective but poorly tolerated
May make generalised epilepsy worse
What are the side effects of topiramide?
Sedation, dysphagia and weight loss = poorly tolerated by patients
What are some issues with prescribing anti-convulsants in women?
Some induce hepatic enzymes with alter the efficacy of the pill
Dose of the morning after pill must be increased
Shouldn’t use progesterone only pill = progesterone implants no longer effective
What is status epilepticus?
Recurrent epileptic seizures without full recovery of consciousness = continuous activity >30mins
What are the types of status epilepticus?
Generalised convulsant = non-convulsant status, conscious but in altered state
Epilepsia partialis continua = continued focal seizures, consciousness preserved
What are the precipitants of status epilepticus?
Severe metabolic disorders = hyponatraemia
Infection and head trauma
Subarachnoid haemorrhage
Abrupt withdrawl of anti-convulsants
Treating absence seizures with carbamazepine
What is convulsive status?
Generalised convulsions without cessation = excess cerebral energy demand and poor substrate delivery cause lasting damage
What can convulsant status lead to?
Respiratory insufficiency and hypoxia, hypotension, hyperthermia, rhabdomyolysis
What are some features of uncontrolled status epilepticus?
Glutamate release, excitotoxicity, neuronal death
What is the initial management of status epilepticus?
Stabilise patient and investigate cause = blood test, CT
Anti-convulsants = phneytoin, kappa valproate
Never give benzodiazepines
What is the treatment for prolonged/serial status epilepticus at home?
Diazepam 10-20mg rectal
Miodazolam 10-20mg buccal (not licensed)
What is the treatment for sustained control of status epilepticus in patients with established epilepsy?
Re-establish usual AED treatment by nasogastric tube/orally or IV for phenytoin
What is the treatment for sustained control of status epilepticus in patients with new or continuing seizures?
Fosphenytoin = 18mg/kg IV with EEG monitoring
Phenytoin = 18mg/kg IV with EEG monitoring
Phenobarbital = 15mg/kg (above options preferred)
Maintain drug levels
What is the management of a patient with status epilepticus that persists after initial treatment?
Transfer to ITU within 1hr of admission
Control status with general anaesthesia = thiopentone or propfol
Monitor control with full EEGs or cerebral function monitor
What are some features of partial status epilepticus?
Suspect in any patient presenting with an acute confusional state = confirm with EEG
Treatment the same as for status epilepticus
