Brainscape's Knowledge GenomeTM

Browse over 1 million classes created by top students, professors, publishers, and experts.


See full index

PR3153 CA1 > IC6&7: Seizures and Epilepsy > Flashcards

IC6&7: Seizures and Epilepsy Flashcards

1
Q

Define an acute seizure

A

result from some immediately recognisable stimulus of cause (occuring in the presence or close timely association (about a week) with an acute brain insult (metabolic, toxic, structural, infectious, hypoxic)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

Define a remote seizure

A

seizures that occur longer than 1 week following a disorder

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

Define epilepsy

A

At least 2 unprovoked seizures occuring > 24h apart

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

What are the two key concepts in the pathophysiology of seizures

A

Hyeprexcitability → enhanced predisposition of a neuron to depolarise (mediated by ion channels)

Hypersynchronisation → promoting the generation of epileptiform activity in a self-perpetuating cycle

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

What are the 5 classes of epilepsy etiology?

A
  1. Structural
    - Hippocampal sclerosis, brain tumours, vascular malformations, glial scarring (including stroke and traumatic brain injury)
  2. Genetic or presumed genetic
    - Dravet syndrome with SCN1A mutations
  3. Neurodegenerative
    - Alzheimer’s disease
  4. Metabolic
    - Inborn errors of metabolism, mitochondrial disorders
  5. Infectious
    - Bacterial meningitis, encephalitis, neurocysticercosis
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

What are focal onset seizures

A

seizures that begin only in one hemisphere, may spread to the contralateral hemisphere, where they will then be known as secondary generalised seizures

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

What are generalised onset seizures

A

seizures that begin in both hemispheres

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

Describe the presentation of a generalised tonic-clonic seizure (Grand mal)

A

beginning with limb stiffening (tonic phase) followed by jerking of limbs and face (clonic phase)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

Describe the presentation of a generalised absence seizure (Petit mal)

A

basic lapse in awareness that begins and ends abruptly, sometimes mistaken as persistent staring

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

What are the 4 symptoms that come with focal onset seizures?

A
  • Motor symptoms → clonic movements (eg. twitching or jerking) of the arm, shouldder, face or leg; speech arrest
  • Sensory symptoms → feeling of numbness or tingling; visual disturbances (flashing lights); rising epigastric sensation
  • Autonomic symptoms → sweating, salivation, pallor, changing BP and HR
  • Psychic (somatosensory) → flashbacks; visual, auditory, gustatory or olfactory hallucinations; affective symptoms include fear (most common), depression, anger and irritability
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

What investigations can be conducted to confirm seizures? (3)

A
  1. Scalp EEG (positive proves, negative does not mean seizures are absent)
  2. MRI (help identify focal lesions)
  3. Biochemical/toxicology (electrolyte abnormalities, serum prolactin, CK levels)
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

What are the 4 means of non-pharmacological management for epilepsy?

A
  1. Ketogenic diet (low carb high fat to induce ketosis)
  2. Vagus nerve stimulation
  3. Responsive neurostimulator system (stimulator implanted in skill w leads to the brain for continuous monitoring)
  4. epilepsy surgery
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

What are examples of seizure triggers? (8)

A
  • Hyperventilation
  • Photostimulation
  • Physical and emotional stress
  • Sleep deprivation
  • Sensory stimuli
  • Infection
  • Hormonal changes (time of menses, puberty or pregnancy)
  • Drugs (eg. theophylline, alcohol, high-dose phenothiazines, antidepressants especially bupripion, tramadol, carbapenems)
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

What are the 1st gen ASMs? (4)

A

carbamazepine
phenobarbital
phenytoin
valproate

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

What are the 2nd gen ASMs? (5)

A

lamotrigene
levetiracetam
gabapentin
pregabalin
topiramate

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

What drugs can be used for new onset focal seizures? (4)

A

carbamazepine
phenytoin
lamotrigene
levetiracetam

(CP, LL)

17
Q

What drugs can be used for refractory focal seizures? (2)

A

clobazam, pregabalin

18
Q

What drugs can be used for new onset generalised seizures? (4)

A

carbamazepine
vaproate
lamotrigene
topiramate

(CV, LT)

19
Q

What drugs can be used for refractory generalised seizures? (2)

A

clobazam, levetiracetam

20
Q

Of the 1st generation ASMs, which drugs are CYP inducers and inhibitors

A

Inducers: carbamazepine, phenytoin, phenobarbitone
Inhibitors: valproate

21
Q

Which drug undergoes autoinduction?

A

Carbamazepine

22
Q

Which drug follows non-linear kinetics?

A

Phenytoin

23
Q

What 4 classes of drugs commonly have DDIs with ASMs?

A
  1. antidepressants
  2. antipsychotics
  3. immunosuppressive therapy
  4. chemotherapy drugs
24
Q

Under what circumstances should phenytoin dosing regime be altered? (2)

(think absorption and DDI)

A

If patient taking >400mg, split dose for better absorption

Space 2h apart from enteral feeds

25
Q

How should phenytoin concentration be calculated for in albumin <40g/L

A

Winter-Tozer eqn

26
Q

What phenomenon is valproate subjected to?

A

Saturable protein binding within therapeutic range (lower protein binding at higher drug concentrations)

27
Q

When does maximum autoinduction occur after initiating carbamazepine

A

2-3 weeks

Hence start at a dose below the maintenance dose

28
Q

What are the 4 broad classes of general SEs in ASMs?

A
  1. CNS (somnolence, dizziness, ataxia)
  2. GI (n&V, especially w CBZ and VPA)
  3. Psych (behavioural disturbances, especially with levetiracetam)
  4. Cognition (slurred speech, especially with topiramate)
29
Q

What should be tested for for hypersensitivity reactions

A
  • HLA-B*1502 genotyping prior to starting carbamazepine
  • HLA-B*1502 positive patients should avoid carbamazepine and phenytoin
30
Q

Which is considered the “clean and easy to use” drug

A

Levetiracetam

31
Q

How should ASM treatment be assessed (when to discontinue)? (4)

A
  • If the patient achieves seizure freedom but has intolerable side effects, decrease ASM dose and monitor
  • If the patient achieves seizure freedom and has optimal QoL for more than 2 years, consider withdrawing ASM
  • If the patient is unable to achieve seizure freedom with monotherapy, lower the dose of the first ASM and add on a second ASM
  • If the patient is still not seizure free, remove the least effective ASM and add another second ASM
32
Q

What are indications for TDM? (4)

A
  • To establish an individual’s “therapeutic range” → this is usually a lab reported reference range which may not be effective for all; once the patient is stable, document effective level which controls seizures while minimising side effects, which helps in subsequent changes (anticipated PK changes, DDIs and medical conditions)
  • To assess lack of efficacy → fast metabolisers, adherence issues, other problems; helps in deciding when to change drugs vs when to rework diagnosis (eg. is this the right drug for the right disease?)
  • To assess potential toxicity → changing physiology, slow metabolisers, changes in disease or drugs (eg. renal (uremia, hypoalbuminemia), liver (CYP enzymes))
  • To assess loss of efficacy (breakthrough seizures) → changes in physiology (age, pregnancy), changes in pathology, changed formulation (brand vs generic, dosage forms), drug interactions
33
Q

What are there reference ranges for the the 4 first generation drugs?

A
  • Carbamazepine → 4-12 mg/L
  • Phenytoin → 10-20 mg
  • Phenobarbital → 15-40 mg/L
  • Valproate → 50-100 mg/L
34
Q

-

A

-

35
Q

Which is the drug of choice in seizures in pregnancy?

A

Levetiractam, lamotrigene

36
Q

What should be taken note for women on lamotrigene?

A

OCs may lower lamotrigene contraceptions resulting in breakthrough seizures

PR3153 CA1 (5 decks)

Brainscape helps you reach your goals faster, through stronger study habits.
© 2024 Bold Learning Solutions. Terms and Conditions