Seizures

Question 1

What are febrile convulsions (pathophysiology and aetiology)?

Answer 1

Seizures associated with fever >37.8’C and not due to other underlying pathology such as epilepsy.

children 6 months to 5 years
relatively common

common causes-
respiratory tract infection
otitis media
UTI
influenza
HHV-6 (sixth disease/roseola infantum)
post-immunisation (rare) 1-2 weeks after recieving the vaccine.

Question 2

Clinical features of febrile seizures

Answer 2

Generalised tonic-clonic seizure
Muscle stiffness and jerking
Shaking of the limbs without focal features

breathing difficulties
pallor
cyanosis
LOC
post-ictal drowsiness and confusion

rarely last longer than 10 mins
occur once in 24 hours

Question 3

What is a complex febril convuslion?

Answer 3

Similar but more focal features e.g movement is limited to one side of the body

15 mins and recur within 24 hrs

Question 4

Febrile status epilepticus

Answer 4

Seizure lasts longer than 30 mins

Occurs in first 24 hours of febrile illness

Question 5

Febrile convulsion investigation

Answer 5

check temp following seizure
focal neurological deficits
bloods- FBC, U+E, ESR, coagulation, glucose

urine: <18M

lumbar puncutre if suspected meningitis

EEG
brain MRI

Question 6

Management of febrile convulsion

Answer 6

Typically self-resolves
Antipyretics- ibuprofen, paracetemol
>5 min or recur= ambulance

Buccal midazolam
Rectal diazepam
repeat if does not abate in 10 mins

Question 7

Urgent referral for febrile convulsion

Answer 7

If alternative cause is suspected (epilpesy)

first presentation
diagnostic uncertainty
aged <18M
abx have recently been taken

Question 8

What are some complications that can follow a febrile seizure?

Answer 8

Todd’s paresis- transient hemiparesis. potential short term complications, usually subside in 48hrs

Non febrile siezure / epilepsy

Febrile status epilepticus.

Question 9

Absence seizure clinical features

Answer 9

“Petit mal”

age of onset 3-10 years old

pically happen in children. The patient becomes blank, stares into space and then abruptly returns to normal. During the episode they are unaware of their surroundings and won’t respond. These typically only lasts 10-20 seconds. Most patients (> 90%) stop having absence seizures as they get older. Management is:

absences last a few seconds
quick recovery
hyperventilation/stress can provoke a seizure
the child is usually unaware of the seizure
can occur many times in the day

EEG: bilateral, symmetrical 3Hz spike and wave pattern

Question 10

Absence seizure management

Answer 10

1st line- sodium valporate, ethosuximide

Question 11

Focal seizures (partial seizures)

Answer 11

The seizures start in a specific area on one side of the brain.

Focal seizures start in temporal lobes. They affect hearing, speech, memory and emotions. There are various ways that focal seizures can present:

Hallucinations
Memory flashbacks
Déjà vu
Doing strange things on autopilot
Motor (Jacksonian March)
clonic, tonic, atonic, myoclonus
automatisms (repeat automatic movements like clapping or rubbing of hands, lipsmacking, chewing or running

Non Motor (aura)
change in sensation, emotion, thinking, cognition, GI, waves of hot or cold, goosebumps, heart racing.

Question 12

Generalised seizures

Answer 12

Involves the networks on both sides of the brain
LOC immediately

1. motor
   - tonic-clonic (grand mal)
   - tonic (tense/rigid)
   - clonic (jerking)
   - myoclonic (brief, rapid muscle jerks) (muscle twitching)
   - atonic (muscles are weak/limp)
2. non-motor
   - absence

Question 13

Focal to bilateral seizure

Answer 13

the seizure starts on one side of the brain and then spreads to both lobes

2’ generalised seizures.

Question 14

Psychogenic non-epileptic seizures

Answer 14

Pseudoseizures
Patients who present with epileptic-like seizures but no EEG changes

history of mental health/personality problems

*e.g. keep their eyes close

Question 15

Infantile spasms (West’s syndrome)

Answer 15

This is also known as West syndrome. It is a rare (1 in 4000) disorder starting in infancy at around 6 months of age. It is characterised by clusters of full body spasms. There is a poor prognosis: 1/3 die by age 25, however 1/3 are seizure free. It can be difficult to treat but first line treatments are:

Prednisolone
Vigabatrin

Question 16

Juvenile myoclonic epilepsy

Answer 16

Infrequent generalised seizures often in the morning
Daytime absences
Sudden shock-like a myoclonic seizure
good response to sodium valproate.

Question 17

Seizure investigation and management

Answer 17

EEG
MRI

Management:
1st line for generalised seizure: sodium valporate
1st line for focal seizure: carbamezepine.

Question 18

DVLA and seizures

Answer 18

Patients cannot drive for 6 months following a seizure

for patients with established epilepsy, they must be fit free for 12 months

Question 19

Sodium valproate

Answer 19

1st line for generliased seizure

increases GABA activiy

Question 20

Carbaezepine

Answer 20

1st line for focal seizures

binds to sodium channels increasing their refractory period

Question 21

Lamotrigine

Answer 21

2nd line for generliased and partial seizures

sodium channel blocker

Question 22

Phenytoin

Answer 22

no longer used due to side effects

binds to Na+ channel increaseing thier refrctory period.

Question 23

Acute mx of seizure

Answer 23

if a seizure does not terminate after 5-10 mins, administer meds

Benzodiazpeines (intranasally or under tongue)

Question 24

Focal seizures (localising features)

Answer 24

Temporal lobe- hallucinations, auditory, gustatory, olfactory. epigastric rising or emotional. automatism lip-smacking, deja vu
(head is temporary)

frontal lobe: head or leg movement, post ictal weakness, Jacksonian march
(motor)

parietal: paraesthesia
(p=p)

occipital: floaters/flashers
(visual)

Question 25

1. Focal onset awareness | 2. Focal onset impaired awareness

Answer 25

1. person is aware during seizure (simple partial seizure) | 2. person is confused / awareness is affected. focal impaired / complex partial seizure.

Question 26

What is the definitionof status epilepticus

Answer 26

A seizure continuing for longer than 5 minutes or when multiple shorter seizures occur with incomplete recovery between them

Question 27

Causes of seizures

Answer 27

``` Known epilepsy Drug overdose (amphetamines, TCAs) drug withdrawal (alchol) CNS injury (traumatic brain injury, acute stroke, SAH, cerebral hypoxia) CNS infection (meningitis, encephalitis, cerebral abscess) ```

Question 28

Initial investigation of a seizure

Answer 28

``` Glucose Venous blood gas (VBG) Full blood count Urea & electrolytes Magnesium Calcium ``` Guided by the likely cause but may include CT head Bloods cultures Toxicology screen Lumbar puncture (LP) 12 lead electrocardiogram (ECG) Look specifically for prolonged PR, QRS and QT interval

Question 29

Clinical feature of seizure

Answer 29

``` Witnessed or unwitnessed Collateral history if possible Prodrome Loss of consciousness Convulsions Tongue biting Urinary incontinence Post-ictal period Injuries ```

Question 30

Initial management of seizure

Answer 30

Secure the airway Give high-concentration oxygen Assess cardiac and respiratory function Check blood glucose levels Gain intravenous access (insert a cannula) IV lorazepam 4mg, repeated after 10 minutes if the seizure continues If seizures persist: IV phenobarbital or phenytoin in community: Buccal midazolam Rectal diazepam

Question 31

Atonic seizure

Answer 31

Atonic seizures are also known as “drop attacks”. They are characterised by brief lapses in muscle tone. These don’t usually last more than 3 minutes. They typically begin in childhood. They may be indicative of Lennox-Gastaut syndrome. Management is: First line: sodium valproate Second line: lamotrigine

Question 32

Myoclonic seizure

Answer 32

Myoclonic seizures present as sudden brief muscle contractions, like a sudden “jump”. The patient usually remains awake during the episode. They occur in various forms of epilepsy but typically happen in children as part of juvenile myoclonic epilepsy. Management is: First line: sodium valproate Other options: lamotrigine, levetiracetam or topiramate

Question 33

management

Answer 33

most neurologists start anti-epileptics following a second epileptic seizure. general rule- sodium valproate is used 1st line with generalised seizures carbamezapine is used for focal seizures.

Question 34

sodium valporate

Answer 34

increases GABA activity 1st line for generalised seizures ``` adverse side effects: weight gain alopecia ataxia tremor *teratogenic* ```

Question 35

carbamezapine

Answer 35

binds to Na+ channels increasing their refractory period first line for focal seizures adverse: dizzy, ataxia, drowsy, SIADH

Question 36

lamotrigine

Answer 36

sodium channel blocker 2n line for generalised seizure adverse: steven johnson syndrome

Question 37

phenytoin

Answer 37

binds to Na+ to increase their refractory period no longer used 1st line as extensive side effect profile