Treatment of Epilepsy l Flashcards
1
Q
Epilepsy related mortality risks (4)
A
- Sudden Unexplained Death in Epilepsy (SUDEP)
- Status epilepticus
- Unintentional injuries
eg drowning, head injuries & burns - Suicide
2
Q
Risk factors for SUDEP (3)
A
- Presence & frequency of tonic-clonic seizures
- Nocturnal seizures
- Lack of seizure freedom
3
Q
Seizure definition
A
- a transient occurrence of signs & symptoms due to abnormal excessive or synchronous neuronal activity in brain
4
Q
Epilepsy definition (3)
A
- At least 2 unprovoked seizures occurring >24h apart
- 1 unprovoked seizure & probability of further seizures similar to the general recurrence risk after 2 unprovoked seizures, occurring over the next 10 years (60%)
- Diagnosis of epilepsy syndrome
- it is a brain disorder characterised by an enduring predisposition to generate epileptic seizures
5
Q
Provoked seizures risk factors (5)
A
- Metabolic
- Toxic
eg illicit drug use, TCA, alcohol, benzodiazepines withdrawal) - Infections
- Inflammations
- Structural
6
Q
Pathophysiology (2)
A
- Hyperexcitability
- enhanced predisposition of a neuron to depolarise - Hypersynchronisation
- intrinsic re-organisation of local circuits
7
Q
Epilepsy risk factors (6)
A
- Genetic
- Structural
- traumatic brain injury, tumours - Metabolic
- Infections
- Immune
- Unknown
8
Q
ILAE classification based on 3 key features
A
- Site seizures begin in
- focal vs generalised - Level of awareness during the seizures
- aware vs impaired - Other factors
- motor or non-motor onset
9
Q
Simple partial seizures
A
Focal onset seizures without dyscognitive featues
10
Q
Complex partial seizures
A
Focal onset seizures with dyscognitive features
11
Q
Epileptic syndromes
A
- epileptic disorder characterised by a cluster of signs & symptoms
12
Q
Focal onset seizures unique feature
A
- dejavu (aura)
13
Q
Generalised onset unique feature (Tonic Clonic)
A
Tonic - rigidity
Clonic - jerking
14
Q
Generalised onset unique features (Absence/Petit Mal)
A
- basic lapse in awareness that begins and ends abruptly
- persistant staring
- mistaken for complex partial seizures
15
Q
Absence/Petit Mal seizures vs Complex Partial Seizures (4)
A
- Not preceded by aura
- Last seconds rather than minutes
- Begin frequently & end abruptly
- Produce characteristic EEG patten (3Hz spike waves)
16
Q
Generalised onset unique features (Atonic)
A
- classic drop attack (astatic seizures)
- sudden lost in postural tone
- collapse to ground like a rag doll
17
Q
Diagnosis of epilepsy (6)
A
- Thorough history taking
- description of seizures
- any aura, preservation of consciousness & post-ictal state - Neurologic examination
- Concomitant medical conditions
- Electroencephalography (EEG)
- MRI with gadolinium
- Biochemistry/toxicology
18
Q
Differential diagnosis (4)
A
- Syncope (fainting)
- Transient ischemic attacks
- Migraine
- Psychogenic non-epileptic seizures
19
Q
Electroencephalography (EEG)
A
- diagnosis of seizures or epilepsy is considered if there are epileptiform discharges on EEG
- a normal EEG DOES NOT exclude possibility of epilepsy
20
Q
Electroencephalography (EEG) limitations
A
- Not all epileptic patients have abnormal EEG
- 50% chance of showing epileptiform activity in a first awake EEG
- 80-90% sensitivity with repeated awake-sleep EEG - EEG can be abnormal in normal persons
21
Q
Situations when MRI with gadolinium is done (2)
A
- adult patients who present with 1st seizure
- patients with focal neurological deficits/suggestions of focal onset seizures
22
Q
Biochemistry/toxicology
A
- helps to rule out electrolyte abnormalities (eg hyponatremia, hypomagnesemia)
- serum prolactin (not routinely used)
- creatine kinase (raised after GTC)
23
Q
Risk of seizure occurrence
A
Risk of second occurrence - 30% within next 5 years, higher in first 2 years - higher in the presence of : ~ epileptiform EEG ~ prior brain insult ~ structural abnomality ~ nocturnal seizures
24
Q
Risk of recurrent seizures after 2 unprovoked seizures
A
70% at 4 years
25
Benefit of initiating treatment after 1st episode of seizures
Reduce the risk of 2nd seizures
26
Limitations of initiating treatment after 1st episode of seizures (2)
1. No effect on long-term prognosis
| 2. No evidence of higher risk of death, injuries or status epilepticus in patients with deferred treatment
27
Factors to consider when initiating treatment (4)
1. Recurrence risk
- 30% after 1 episode
- 70% after 2 episodes
2. Potential seizure morbidity
3. Risk of treatment
eg ADR
4. Personal circumstances
eg compliance to medication
28
Treatment goals for epilepsy (3)
1. Absence of epileptic seizures (symptoms)
2. Absence of anti-epileptic drug SE
3. Attainment of optimal quality of life
2/3 of patients are able to achieve seizure-freedom
29
Types of treatments for epilepsy
1. Pharmacological ASM (mainstay)
- monotherapy preferred
2. Non-pharmacological
- Keto diet
- Vagus Nerve Stimulation
- Responsive Neurostimulator System (RNS)
- Epilepsy surgery
- Seizure diary
30
Factors influencing ASM choice (6)
1. Seizure type
2. Epilepsy syndrome
3. Co-medication
4. Co-morbidity
5. Patient's preference
6. National/Institutional
- costs
- guidelines
31
Rapid titration required
Cannot use lamotrigine & topiramate (req slow titration)
32
Epilepsy with migraine
Use topiramate
33
Epilepsy with depression/anxiety
Caution when using levetiracetam
34
Women with child bearing potential
Avoid valproate
| Consider levetiracetam & lamotrigine
35
Monotherapy ASM treatment benefits (6)
1. Lower incidence of ADR
2. Absence of DI
3. Reduced risk of birth defects
4. Lower cost
5. Easier to correlate response & ADR
6. Better adherence
36
Dosing features of ASM initiation (1st line)
1. Start low
2. If seizure continue but no SE
- increase dose of ASM
3. If seizures continue despite max tolerated dose or intolerable to SE at low doses
- review diagnosis & drug appropriateness
- check adherence
- change ASM
4. If patient tolerates 1st and 2nd line agent but with suboptimal responses
- combination ASM therapy
37
Drug resistant epilepsy
- failure of adequate trials of 2 tolerated ASM
| - regardless monotherapy or in combination
38
Keto diet
- for patients that cannot tolerate or have not responded well to ASM treatment
- comprises of low carb high fat diet to induce ketosis
- used mainly in children to prevent seizures
- challenging to adhere long term
39
Epilepsy surgery
- not usually advocated early
| - advocated early therapy for specific epileptic syndromes
40
Patient education for epilepsy (4)
- avoid preventable seizure triggers
- counsel on ADR & potential DDI
- activities (unintentional injuries from seizures)
eg swimming
- community resources available to support them
41
Seizures triggers (9)
1. Hyperventilation
2. Photostimulation
3. Physical & emotional stress
4. Sleep deprivation
5. Electrolyte imbalance
6. Sensory stimuli
7. Infection
8. Hormonal changes
eg pregnancy, menses, puberty
9. Drugs
eg TCA, anticholinergics, bupropion
42
First aid for seizures (7)
1. Ease the person to the floor
2. Turn the person gently to 1 side to help breathing
3. Clear the area around the person to prevent injury
4. Put something soft/flat under heard
5. Remove eyeglasses
6. Loosen ties or anything around the neck
7. Time the seizures (if >5min call 995)
43
Things not to do on patients with seizures (4)
1. Do not hold the person down
2. Do not put anything in the person's mouth
3. Do not try to give mouth-mouth breathing
- even if look pale (hypoxia after tonic)
4. Do not offer food/water until patient is fully alert
44
Focal onset
1 hemisphere affected
45
Generalised onset
Both hemispheres affected
46
Ion channels (4)
Depolarise :
1. Na+
- influx
2. Ca2+
Hyperpolarise :
1. K+
- efflux
2. Cl-
