Seizures Flashcards
What is a seizure?
a seizure is a transient occurrence of signs and/or symptoms due to abnormal excessive neuronal activity in the brain
[esp vs blackouts which is a transient LOC due to global cerebral hypoperfusion]
(key part is presence of symptoms/signs is key to definition as only occur in whole organsims)
What is a focal seizure?
a focal seizure has a discrete cortical origin
–> strange sensations or jerking movements
what types of focal seizure did there used to be/what have they become now according to Prof. H. Cock?
- FOCAL AWARE: (previously: simple)
- maintain consciousness
- FOCAL UNAWARE (previously: complex)
- altered awareness or LOC
-
+/- emotional disturbance and automatism -
- fried reticular formation –> e.g. the neuronal pathways in the brainstem connecting the spinal cord, cerebrum and cerebellum, mediating the overall level of consciousness
What is a primary generalised seizure?
primary generalised seizure:
- usually involves both hemispheres upon onset
- & usually loss of consciousness
What is a secondary generalised seizure?
- a type of focal/partial seizure that spreads to both hemispheres
- thus develops into a generalised seizure
What are the types of partial/focal seizure?
they are split to the parts of the brain they can be localised to, TF the types of focal seizures are:
- temporal lobe
- frontal lobe
- parietal lobe
- occipital lobe
*
Carbamazepine or lamotrigine are most commonly used for which seizure type: partial or generalised?
carbamazepine or lamotrigine are used for partial/focal seizures
e.g. ones in temporal, frontal, parietal, occipital lobes
sodium valproate is an AEDs used in which type of seizure: focal or generalised?
sodium valproate is an AED used in generalised seizure types
e.g. tonic, atonic, clonic, tonic-clonic, myoclonic or absence
Temporal lobe focal seizures show particular symptoms due to where in the brain is experiencing abnormal excessive neuronal activity.
The acronym for temporal lobe seizures is ADDFAT, what does this stand for?
- A - Aura
- [intense emotional, memory, epigastric rising (rising sensations in abdomen)
- D - Deja Vu / Dysphagia
- ictal or post ictal (/foaming at mouth TF?)
- D - Delusional behaviour
- [hallucinations- complex sensory experiences - can be auditory, gustatory, olfactory]
- F - Fear
- (often hippocampal involvement –> sudden terror, panic, anger or elation, derealisation)
- A - Automatisms
- (lip smacking/grabbing etc)
- T - Taste/smell
- (uncal involvement - hallucinations of smell or taste or dreamlike state)
Frontal lobe focal seizures show particular symptoms due to where in the brain is experiencing abnormal excessive neuronal activity.
The acronym for frontal lobe seizures is JAM, what does this stand for?
J - Jacksonian march
- seizure starts in one muscle group and spreads ro other groups often starting at thumb of face
A = pAlsy e.g. todds palsy, typically limbs/but can be all body wekness on just L or R sides etc - post ictal, lasts minutes to hours - usual resolution e/i 48hrs
M - motor features including motor arrest; posturing, versive head movements, peddling movements of legs,
+ dysphagia or speech arrest, subtle behavioural differences
(NB: frontal lobe contians the 1o motor cortex while temporal contains 1o sensory)
PARIETAL lobe focal seizures show particular symptoms due to where in the brain is experiencing abnormal excessive neuronal activity.
What are the symptoms of parietal lobe seizure?
- sensory disturbances - tingling, numbness and rarely pain
- motor symptoms - spread to pre-central gyrus
- aura - motor, simple sensory
*
Occipital lobe focal seizures show particular symptoms due to where in the brain is experiencing abnormal excessive neuronal activity.
What are the symptoms of occipital lobe seizure?
visual hallucinations aura (coloured)
visual pohenomena e.g. spots lines, flashes
What are the different types of generalised seizure?
- Tonic: stiff/flexed - fall BACKWARDS
- Atonic: muscles relaxed - fall TOWARDS
- Clonic: convulsions
- Tonic-Clonic: tonic phase followed by convulsions - often produce an epileptic cry ~30s
- Myoclonic: short muscle twitches
- Absence: impaired awareness & responsiveness - only outward sign is person looking spaced out
- This type of seizure presents between 3-10y/o
- commoner in Girls > Boys
- can be provoked by hyperventilation or stress
- they are normally unaware of the seizure
- they may occur many times in a day
- it lasts a few seconds and is associated with a quick recovery
What would the EEG show of this seizure type?
this is an absence seizure
EEG: bilateral, symmetrical 3Hz spike and wave pattern
What are the classic signs of a seizure/ seizure markers?
- Duration LoC/Amnesia >5 mins
- prodromal focal features
- seizure activity (tonic/clonic/automatisms etc)
- motor features: head turning, ususual posturinig, prolonged
- tongue biting (lateral)
- incontinence
- injury
- post-ictal confusion [THIS IS PATHOGNOMONIC, you dont get confusion with syncope…]
What can cause a seziure?
Almost any brain injury if severe enough, causes seizures (- useful for animal models)
- acute symptomatic seizures occur within hours/days of insult
- Metabolic upset (low Na or Ca)
- Traumatic brain injury – concussive seizure
- Stroke/haemorrhage – at time of the stroke
- Alcohol & recreational drugs - Alcohol withdrawal peak timing is ~36hrs (~1.5d)
- Infection (encephalitis)
- Febrile seizures (infants)
- Structural
- Epilepsy: unprovoked, remote symptoms
- Psychogenic non-epileptic seizures
- Neoplasm
- Tuberous sclerosis, sarcoidosis, PAN, SLE
- Uraemia
What is the typical age group of febrile seizures?
- 6 months - 5 yrs
- ~3% of children will have at least 1x febrile convulsion & these usually occur early in a viral infection due to the temperature rising rapidly
- seizures are typically brief and generalised tonic/tonic-clonic in nature
- A febrile convulsion cay cause hippocampal sclerosis –> structural causes of seizures
What are the structural causes of seizures?
cortical scarring
developmental
DOL
hippocampal sclerosis (after a febrile convulsion)
vascular malformations
What do you ask in a seizures history?
- Before = aura, trauma, screen for other pathologies - headache?
- Previous risk factors, circumstances, posture, prodrome
- During = can you act out what they were doing, urinary incontinence, trauma?
- Witness account where possible, duration, LOC
- After =
- post-ictal state (5-30mins - strong seizure marker)
- how long to return to usual self?
- confusion?
- blood in mouth (tongue biting)
- tired (use up lots of glucose doing tonic clonic)
What investigations are done for seizures?
- ABCDE, blood glucose, GCS
- Vitals, bloods, imaging for Traumatic brain imaging–>
- CTH/MRI
- EEG
- RAISED PROLACTIN IN SEIZURES
What are the differentials for a drop attack?
- CVS problems
- acute brain disturbance
- metabolic cataplexy
What are the differentials for a loss of awareness?
- syncope
- panic attack
- hypotension
- hypoglycaemia
- sleep
What are the differentials for convulsions?
- Movement disorders
- dissociative non-epileptic seizures
What are the differentials for transient focal symptoms?
- TIA
- demyelinating disease
- vestibular
- migraine NB: can get vestibular migraines etc…
- psychiatric
What are the differentials for attacks in sleep?
- hypnic jerks,
- restless legs,
- sleep apnoea,
- parasomnias…
What is the first aid Rx for any seizure?
the acronym is ACTION
A - assess ?safe place / dont touoch mouth
C - cushion head
T - time the fit/seizure
I - identify - red brarcelet/ID
O - over –> on recovery position
N - never restrain!
get IV access; O2 - not co-ordinating breathing; anti-epileptics if known epilepsy
What is epilepsy?
what is epilepsy vs a seizure
epilepsy = recurrent unprovoked seizures
[e.g. a provoked seizure is something that if it happened to anyone would give a seizure e.g. trauma/infection]
Epilepsy = a disorder of the brain characterised by enduring predisposition to generate epileptic seizures and by the neurobiological, cognitive, psychological & social consequences of this condition
a seizure = pathologic neuronal activation leading to abnormal brain function
What is required for a diagnosis of epilepsy (recurrent, unprovoked seizures)?
- 2 or > unprovoked or reflex seizures >24h apart
OR
- 1x unprovoked or reflex seizure but increased risk e.g.
probability of further seizures to general recurrence risk >60% after 2 unprovoked seizures occuring over the next 10 years
OR
- Dx of an epilepsy syndrome
What are some RF for babies to have epilepsy?
- Babies small for their age,
- Babies who have seizures in the first month of life
- Babies who are born with abnormal areas in the brain
Using vitamin CDEF surgical seive what are the RF for epilepsy?
- Vascular - bleeding into the brain, abnormal BV in the brain, stroke from arteries blockage
- Infective/inflam - infections of brain abscess, meningitis or encephalitis
- Trauma - serious brain injury or lack of O2 to brain, early post-traumatic seizures (e.g. occur within days of head injury NB: unlikely to get epilepsy from a mild head injury)
- Autoimmune
- Metabolic - illegal drugs e.g. cocaine
- Iatrogenic/ Idiopathic - 2/3rds of epilpepsy cause is idiopathic
- Neoplastic - brain tumours
- Congenital - cerebral palsy, Autism
- Degenerative - conditions with intellectual and developmental disabilities,
- Endocrine
- Functional - Fhx of fever related seizures or fever seizures that are very long / status epilepticus