Epilepsy Flashcards
Background
DEFINTION:
Seizures are sudden violent emotions or actions of the electrical properties of the cerebral cortex and happen when a sudden imbalance occurs between the excitatory and inhibitory signals within the network of cortical neurons in favour of a sudden-onset of net excitation.
- Other affected areas of the primary cortex will cause sensory, gustatory, or motor manifestations
Generalised onset seizures - affects whole brain
Focal/partial onset seizures - localised origin of seizures
- Prolonged or repeated seizures and convulsive status epilepticus - Prolonged seizures (>30 min) OR a continuous state of seizures one after another.
- Non epileptic onset seizures - behavioural, febrile seizures, posttraumatic, reflex (vagal nerve stimulation), preeclampsia and eclampsia.
Signs and Symptoms
General symptoms: Jerking, blank stare, hand rubbing, random noises, tingling in arms and legs, loss of consciousness, sudden fall.
Type of seizure defines the signs shown.
Types can be partial or generalised:
PARTIAL (FOCAL) - just 1 part of brain:
- Simple - no loss of consciousness
- Complex - impaired consciousness
- Secondary generalised - Evolves to generalised
GENERALISED:
- Tonic clonic (grand mal) - Period of increased muscle tone + jerking.
- Absence ( petit mal) - Loss of motor activity
- Myoclonic - Single/repetitive jerking 1 or more muscle groups
- Atonic (drop attacks) - Loss of muscle tone 1 or more muscle group
- Tonic - Immediate increased muscle tone
- Clonic - Repetitive jerks
Tonic clonic most common generalised - whole body stiffens, then consciousness lost, T for tight, C for convulsions.
Referral and follow up
- Refer for ALL urgently within 2 weeks after 1st suspected seizure.
- Same applies for remission people
- After 1st seizure asses the risk of a 2nd. Children with afebrile seizure more at risk than children with febrile (Seizure with fever) seizure.
- After 1st seizure give advice on:
How to see another seizure, first aid and what to do in case of seizure, how to prevent seizure, who to contact if seizure occurs.
Diagnosis
- Detailed history
- Exclude cardiac related conditions using 12 leads Electrocardiogram (ECG).
- Exclude metabolic abnormalities.
- Request Electroencephalogram (EEG). If EEG is normal, consider sleep deprived EEG or ambulatory EEG before excluding epilepsy diagnosis.
- Neuroimaging MRI or CT scan if MRI is contraindicated.
- Repeat scanning only if new epilepsy features manifested.
- Genetic testing.
- Antibody testing.
- Provide information and support.
- Ensure adherence to therapy.
BEFORE initiation/ REVIEWS
Before initiation of therapy for women and girls review:
- Contraception
- Folic acid supplementation
- Conception
- Pregnancy
- Breastfeeding
- Caring for children
- Menopause
Arrange regular (minimum annual) monitoring reviews any1 at risk of SUDEP, people with serious comorbidities, Pregnant, Ppl with uncontrolled seizures, Ppl with poor adherence, and those with AEs to meds.
Key points on AED
Mono preferred ALWAYS
- Start low and increase dose slowly.
- Don’t stop abruptly withdraw slowly (2-6mnts)
- Use same brand for CP3
- ALL cause suicidal thoughts and some are Teratogenic (SV, topiramate, phenytoin, phenobarbital, carbamazepine)
Drug choice depends on seizure type, syndrome type, need, risks/benefits, age, sex, comorbidities, concomitant use, personal circumstance.
DOSAGE determined by drug half life - Keep as low as possible Most are BD. Lamotrigine, perampanel, phenobarbital, phenytoin = long half-lives, can be given ON. (LP3 -Long period 3)
BUT large doses may need to be spread out to avoid AEs
Treatment should be monotherapy 1st with
1st line
FAILS then try a 2nd drug monotherapy.
- BUT b4 trying diagnosis need to be reconfirmed.
Changing drug need to be cautious and slowly withdraw from 1st drug once new drugs established.
still FAIL then combo can be done.
NOTE: increased risk of AEs.
If this FAILs then revert regimen (combo/mono).
Treatment (Adults)
Mnemonics are for 1st and 2nd line
Absence, myoclonic, atonic/tonic seizures may exacerbated if on carbamazepine, gabapentin, lamotrigine (not for atonic/tonic), oxcarbazepine, phenytoin, pregabalin, tiagabine, or vigabatrin.
@ SODIUM VALPROATE males, and females unable to have children or female <10 who wont need treatment when old enough to conceive.
TYPES AND TREATMENT:(BNF)
FOCAL: (LL)
- 1st line - lamotrigine or levetiracetam
- 2nd line - carbamazepine, oxcarbazepine, or zonisamide
- 3rd line - Lacosamide
Adjuvant =
- 1st line - carbamazepine, lacosamide, lamotrigine, levetiracetam, oxcarbazepine, topiramate, or zonisamide.
- 2nd line - brivaracetam, cenobamate (NOT in children), eslicarbazepine acetate, perampanel, pregabalin, or sodium valproate
- 3rd line - phenobarbital, phenytoin, tiagabine, or vigabatrin.
Generalised:
TONIC-CLONIC: (S.ALL)
1st line - Sodium valproate@, lamotrigine or levetiracetam
- Male/unable to have kids female Sodium 1st.
Female childbearing potential others are 1st line avoid sodium unless adjuvant
Adjuvant:
- 1st line - clobazam, lamotrigine, levetiracetam, perampanel, sodium valproate@, or topiramate.
- 2nd line - brivaracetam, lacosamide, phenobarbital, primidone, or zonisamide
ABSENCE: (ES.ALL)
- 1st line - Ethosuximide
- 2nd line - Sodium valproate@,
- 3rd line/Adjuvant - lamotrigine or levetiracetam.
MYOCLONIC: (S.ALe)
- 1st line - Sodium valproate@ , Levetiracetam
- 2nd line/Adjuvant - brivaracetam, clobazam, clonazepam, lamotrigine, phenobarbital, piracetam, topiramate, or zonisamide
ATONIC OR TONIC: (SL.ARCT)
- 1st line - Sodium valproate@, Lamotrigine,
- 2nd line/Adjuvant - clobazam, rufinamide, or topiramate
- ALL fail adjuvant - felbamate under neurologist supervision.
Epilepsy syndromes and Treatments
Dravet syndrome:
- 1st line - Sodium valproate - even for women
- ALT - Triple therapy adjunctive Clobazam + Stiripentol
- 2nd line triple therapy adjunctive Cannabidiol + Clobazam
- Fenfluramine - ALT adjunctive
- Under neurologist supervision ALT topiramate or levetiracetam, lastly potassium bromide.
- Seizures can exacerbate with carbamazepine, gabapentin, lacosamide, lamotrigine, oxcarbazepine, phenobarbital, pregabalin, tiagabine, or vigabatrin.
Lennox-Gastaut syndrome:
- 1st line - sodium valproate even for women.
- Fail then = Lamotrigine 2nd line or adjunctive.
- 3rd line adjunctive - Cannabidiol + clobazam. OR clobazam, rufinamide, or topiramate.
- Under supervision ALT Felbamate
Infantile spasms:
Tuberous sclerosis
- 1st line - Vigabatrin
- Fail then ADD prednisolone
Other causes
- 1st line - Vigabatrin + prednisolone
- ALT - Tetracosactide
Repeated or cluster seizures, prolonged seizures, and status epilepticus and Treatments
ALL are medical emergency
Repeated or Prolonged seizure:
- Repeated = 3 or + self terminating seizures in 24 hours)
- Prolonged = seizure that continues for >2 mins longer than patient’s usual seizure
Treatment:
- Follow emergency management plan if unavailable THEN
- Clobazam or midazolam Urgent.
Status epilepticus:
- Convulsive status epilepticus- seizure that lasts for ≥5 mins
Treatment:
- Position PT to avoid injury, support respiration i.e. give O2, maintain BP, Correct hypoglycaemia
- Parenteral Thiamine if alcohol abuse sus.
- Pyridoxine HCl if caused by Pyridoxine deficiency.
- Follow emergency management plan if available. IF NOT THEN= Urgent buccal midazolam or rectal diazepam in COMMUNITY.
- HOSPITAL IV lorazepam. (children use RECTAL PARALDEHYDE)
IF FAIL THEN: - Call emergency service/get advise. continue management plan if can if not give 2nd dose of benzos if seizure dont stop within 5-10 min of 1st dose.
IF STILL FAIL THEN: - 2nd line try IV levetiracetam, Phenytoin or Sodium valproate.
IF STILL FAIL THEN: - Specialist - 3rd line IV phenobarbital or general anaesthesia.
IF CHANCE OF REOCCUR MAKE MANAGMENT PLAN.
Non-convulsive status epilepticus:
- if incomplete loss of awareness continue or restart oral AEDs. IF FAIL/ have complete lack of awareness then treat same as convulsive status epilepticus.
Febrile convulsions:
- Treat fever
- IF prolonged Febrile convulsions (≥5min) or recurrent treat same as convulsive status epilepticus
Neonatal seizures-
Can occur Before delivery but most common 24 hours after.
- Phenobarbital where there is risk of reoccurrence ALT phenytoin.
- Midazolam + Rectal paraldehyde - management in acute 1s.
- ALT lidocaine HCl BUT not given if they used phenytoin infusion - cardiac toxicity risk
Treatment withdrawal
When discontinuing for anyone whose been seizure free for 2 years or + conduct individual assessment (INC. SUDEP and driving) before stopping.
- Discontinue slowly (at least 3 months or + for benzos, barbiturates) [can be 6mnths or + in benzos)
- Discontinue 1 med at a time.
- IF seizure occurs then reverse las action (last discontinuation/dose reduction)
After surgery discontinue meds under specialist advise
Epilepsy driving and brand switching
Driving:
- If driver has seizure they must stop immediately and tell DVLA.
- 1st unprovoked epileptic seizure/single isolated seizure STOP driving for 6 months unless asses as fit to drive.
- to established epilepsy to drive need to be seizure free for 1 year or not have history of unprovoked seizures.
- Seizure whilst asleep not allowed to drive for 1 year from date unless history/ pattern of sleep seizures OR established pattern of purely asleep seizures.
-DVLA also say dont drive 6 months if meds changed. if seizure occurs can lose license for 1 year.
Brand switching:
3 categories:
- Category 1: HAS TO STAY SAME BRAND eg (CP3)
carbamazepine, phenytoin, phenobarbital, primidone. - Category 2: Change based on clinical judgment and consultation with patient/carer eg:
Valproate, lamotrigine, clobazam, clonazepam, oxcarbazepine, eslicarbazepine acetate, topiramate, zonisamide, rufinamide, perampanel - Category 3: Can change brand eg Levetiracetam, brivaracetam, lacosamide, tiagabine, gabapentin, pregabalin, ethosuximide, vigabatrin
Epilepsy Pregnancy/Breast feeding
Pregnancy:
Risk teratogenicity. ESP in 1st trimester and using 2 or + drugs.
- Highest risk if valproate - AVOID unless PPP
- Other increased risk AEDs - CP3, LP3
- Topiramate increased risk of congenital malformations (cleft palate) if take in 1st trimester. Monitor foetal growth
Provide folate supplementation b4 conception and throughout 1st trimester to reduce risks
Plasma conc. of AED (ESP lamotrigine, phenytoin, carbamazepine) can be affected by physiological changes during pregnancy and post-partum.
- so dose adjustment needed
Routine VIT K injection at birth reduces neonatal haemorrhage risk.
- Encouraged to breast feed monitor closely if risks occur.
- Monitor infants for AEs and development issues.
AEs: sedation, feeding issues, drowsiness
May have withdrawal effects in new born with benzos/Phenobarbital
Breastfeeding
Monitor infants for sedation, feeding issues, inadequate weight gain & developmental milestones.
Primidone, Phenobarbital, Benzos cause drowsiness in BF babies so CAUTION.
Withdrawal effects can appear if mother suddenly stops BF.
Antiepileptic hypersensitivity syndrome
RARE but can be fatal syndrome with some AEDs
- Symptoms start between 1-8 weeks (monitor AEDs 1st 2 months)
- Common symptoms: Fever, rash, liver dysfunction, renal & pulmonary abnormalities, multi organ failure
Possible drugs;
CP3, Rufinamide, lamotrigine, lacosamide.
Action to take: STOP ASAP and REFER.
AED MHRA
ALL AEDs increase risk of suicidal thoughts & behaviour
- Symptoms can happen 1 week after starting.
- PT seek medical advice if occurs.
FOR interactions best to learn enzyme inhibitors/inducers
