CPT: Epilepsy Flashcards

1
Q

What is epilepsy?

A

A neurological disease that has a range of symptoms that are associated with a moment of scncronized abnormal electrical activity in the brain

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

Who is effected by the disease?

A
  • Over 65s
  • Young children
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

What causes it?

A
  • 70% - unknown

30%:

  • head trauma
  • posioning
  • infection
  • maternal injury
  • cardiovascular
    *
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

How is Epilepsy diagnosed?

A
  • Detailed history taken - eye witness may be needed as when seizure their mind will be blank
  • Physical exam
  • Blood tests
  • ECG
  • EEG
  • imaging: CT scan, MRI
  • NEuropsychological assessment
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

Seizures are broken up into different classes depending on what?

A
  • Where they start in the brain (onset)
  • Whether or not the persons awareness is affected
  • whether or not seizures involve other symptoms such as movements
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

Why would an MRI be used?

A

To see potential area in the brain that have been damaged or a brain tumour

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

What is EEG?

A

Electroencephalography

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

What classifications of seizures are there?

A
  1. Focual (awarenes/ impaired): when affects only a part of the brain
  2. Generalised: Affects both hemispheres
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

Describe focal awareness seizures

A
  • Affects only a small part of the brain
  • Person is conscious
  • Range of symptoms depending on the affected area: Tingling (sensory), twitching (motor), flashing lights (visual)
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

Describe focal impaired awareness seizures

A
  • Affects a larger part of one hemisphere
  • Person may be confused
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

What is automatism?

A

Strange repetitive movements

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

Describe generalised seizures

A

Affects both hemispheres

  • Abscene
  • Tonic clonic
  • Atonic
  • Myoclonic
  • stratus epilepticus
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

What is absence?

A

Blank, unresponsive, breifly unconscious

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

What is tonic clonic

A

Unconscious, muscle become stiff (tonic) and then shake and jerk (clonic). After wards patient feels tired and has a headache

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

What is Atonic?

A

Muscles relax

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

What is myoclonic?

A

Conscious muscle jerk

17
Q

What is stratus epilepticus?

A

Seizures lasting more than 5 minutes

18
Q

What is the pathophysiological cause of seizures?

A
  1. Membrane depolarisation

Alterations in NA (reduce threshold/ increase AP rate) or K channel function and/or extracellular potassium pump

  1. Increased Excitation

Release of excitatory AA - Glutamate

  1. Decreased inhibition

Reduced inhibitory transmission - GABA mainly

19
Q

What are the sequence of events that occur during a seizure?

A
  1. Intitation- High frequency burts of APs
  2. Syncronisation- hyper-syncronisation of the neuronal population. Leads to hyper excitability
  3. Propagation- Loss of surrounding inhibition and recruitment via antatomical connections. Propagates across both hemispheres
20
Q

What are the aims for antiepileptic drugs? (AEDs)

A
  1. stabilize membrane potential and prevent depolarisation by action of on ion channels (K, Na, Ca)
  2. Increase inhibitory (GABA) transmission
  3. Decrease excitatiry transmission (Glutamate)
21
Q

What are targets for where AEDs will act?

A
  • Inhibit Ca/ Na channels
  • Activate K channels
  • Increase GABA transmission
  • Decrease glutamate transmission
22
Q

What is the mechanism of action of phenytoin?

A

Phenytoin binds to the inactive state of the Na channel and temporaly blocks and delays its activation

23
Q

What are sites of action for AEDs - excitatory synapes?

A
  1. Na channels in nerve terminals - phenytoin
  2. Ca channels - reduces NT release - Gabapentin
  3. Acts on glutamate receptors (NMDA, AMPA) - less likely to work
  4. Activate K channels
24
Q

What are sites of action of AED - inhibitory synapes?

A
  • Release Gaba - benzodiaepens, barbituates
  • Block reuptake of GABA - round for longer
  • MOdify degradation of GABA
25
Q

What are examples of AEDs and where they act

A
  1. Na channels - phenytoin, lamotrigine
  2. Ca - Gabapentin, sodium valporate
  3. K - Retigabine
  4. Enhance GABA transmission - Benzos, barbituates
  5. Inhibit EAA transmission - valporate