Epilepsy Flashcards
What is the difference between seizure and epilepsy?
A seizure is a transient occurrence of signs and or symptoms due to abnormal excessive or synchronous neuronal activity in the brain.
Epilepsy is defined by any of the following:
- at least two unprovoked seizures occurring > 24h apart
- one unprovoked seizure and a probability of further seizures similar to the general recurrence risk after two unprovoked seizures
- diagnosis of an epilepsy syndrome
What are some causes of provoked seizures?
- electrolyte imbalances
- toxic substance/drugs
- traumatic brain injury
- stroke
- CNS infection
- febrile illness
What is the pathophysiology of epilepsy?
Hyperexcitability:
- enhanced predisposition of a neuron to depolarize
- K+, Na+, Ca2+, and CL- ion channels
Hypersynchronization
How do we classify seizures?
Based on mode of onset (focal or generalized) and impairment of consciousness (with or without dyscognitive features)
What is the clinical presentation for focal onset (without dyscognitive features) seizures?
- clonic movements like twitching or jerking
- speech arrest
- feelings of numbness or tingling
- flashing lights
- rising epigastric sensation
- sweating, salivation or pallor
- BP and HR
- hallucinations
- fear, depression etc.
What is the clinical presentation for focal onset (with dyscognitive features)?
- presence of aura
- impaired consciousness
- automatisms like lip smacking
What is the clinical presentation of generalized onset tonic clonic seizures (GTC)?
- begins with stiffening of the limbs (tonic phase), followed by jerking of limbs and face (clonic phase)
- during tonic phase, breathing may decrease or cease -> cyanosis can occur, typically returns during clonic phase
What investigations are used in diagnosis of epilepsy?
- If diagnosis of seizures or epilepsy is considered, epileptiform discharges on Electroencephalogram (EEG) confirm the diagnosis.
- MRI to identify any focal lesions
- biochemical tests -> help to rule out electrolyte abnormalities
When do we usually start pharmacological treatment for epilepsy?
After two unprovoked seizures
What are the non-pharmacological therapies used in epilepsy?
- ketogenic diet (especially in young children)
- vagus nerve stimulation (VNS)
- responsive neurostimulator system (RNS) -> implant a stimulator in the skull
- surgery -> remove a part of the brain
- having a seizure diary
What is the general treatment for epilepsy?
Monotherapy is preferred.
To initiate treatment, start with low dose of a first line AED appropriate for particular seizure type. If seizures continue but no side effects occur, gradually increase the dose of AED.
What are some psychosocial issues associated with epilepsy?
- social stigma (marriage and starting a family)
- employment issues
- prohibited from driving in singapore
- caregiver burden
What are some common seizure triggers?
- hyperventilation
- photostimulation
- physical and emotional stress
- sleep deprivation
- electrolyte imbalance e.g. hypoglycemia, hyponatremia, etc
- sensory stimuli
- infection
- hormonal changes eg during mensus, puberty or pregnancy
- drugs
What is appropriate seizure first aid?
For generalized tonic clonic seizures:
- ease person to floor
- turn person gently onto one side -> help person breathe
- clear the area of anything hard or sharp
- put something soft and flat under his head
- remove eyeglasses
- loosen ties or anything around the neck which may make it hard to breathe
- time the seizure. if last longer than 5 mins, call ambulance.
What are the factors that influence ASM choice?
- seizure type
- co-medication and comorbidity
- patient’s lifestyle and preference
- guidelines, availability and costs
What are the five first line treatment options for focal onset epilepsy?
- carbamazepine
- levetiracetam
- valproate
- lamotrigine
- oxcarbazepine
non-guideline
- phenytoin
- topiramate
- gabapentin
What are the three first line options for generalized tonic clonic epilepsy?
- lamotrigine
- valproate
- carbamazepine
non guideline:
Topiramate
