Term
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Definition
“Sudden change in behavior caused by
electrical hypersynchronization of neuronal
networks in the cerebral cortex”
• 8–10% of the population experiences a
seizure in their lifetime
• 1–2% of all ED visits • 25% of these are primary episodes |
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Term
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Definition
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Term
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Definition
• Outer layer of brain
• Divided into two
hemispheres • Four lobes on each
hemisphere
• Key functions include:
higher level thought
processing,
language, wareness,
consciousness |
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Term
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Definition
So we have focal and generalized seizures. Those are just general seizure types. And then unknown, which usually then later become classified, depending on a little bit more information if they repeat-- that sort of thing. And we'll get into these classifications.
Epilepsy itself has different types as well-- focal, generalized, combined general and focal, and unknown. And you can see here with all these different categories, this is why I'm saying you want this slide that's upcoming printed out so that you can actually follow along with this.
The etiology of these is multi-factoral. Like most things that we talk about, it can have a lot of different causes. It can be a combination of causes that lead to the seizures. And this will help us determine if this is a one-off thing, this is just something that's a result of one of these changes, or is this a seizure or something that's underlying and the person is going to be at risk for having multiple seizures. That changes our immediate management and also changes our long-term management. |
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Term
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Definition
-Childhood onset:
• Typically genetic, metabolic, or congenital
structural
- Adult onset:
• Typically acquired vascular, degenerative, or
neoplastic
Approximately 60% of patients have
unknown etiology |
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Term
| Initial Classification Approach |
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Definition
• Seizure vs. mimicking event?
- Syncope, migraine, TIA, panic attack,
narcolepsy with cataplexy
• Result of treatable event vs. intrinsic
dysfunction of CNS?
- Helps determine likelihood of repeat event,
treatment approach |
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Term
| acute asymptomatic seizure |
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Definition
• At time of or in close temporal association with
documented brain insult
• Withdrawal, CVA, trauma
• Low risk of repeat events |
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Term
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Definition
• Unknown etiology, in relation to preexisting brain lesion or nervous system disorder
• Higher risk of repeat events |
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Term
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Definition
• ≥2 unprovoked
≥24 hours apart
• One unprovoked and probability of further similar seizures similar to if ≥2 unprovoked |
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Term
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Definition
Primary: no problem with brain structure or
chemistry, but EEG is consistent with seizure
-Common familial link
• Secondary: suspected problem in brain
structure or chemistry
- Associated with developmental delays |
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Term
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Definition
• Updated by the International League
Against Epilepsy (ILAE) in 2017
• Removed category of partial seizures and
replaced with focal
• Outdated partial seizures:
- Simple partial: awareness remains intact
- Complex partial: impaired awareness; confused,
partial awareness, complete unawareness |
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Term
Seizure Classifications
• New ILAE system: |
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Definition
Where did the seizure begin in the brain?
• What level of awareness was present?
• What other features were present? |
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Term
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Definition
• One area of brain involvement
• Focal impaired awareness
• Previously complex partial
• Focal aware
• Previously simple partial |
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Term
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Definition
• Involve both brain hemispheres
• All presumed to affect awareness or some level of consciousness |
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Term
| focal to bilateral seizure |
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Definition
Starts on one side of brain and quickly spreads to both hemispheres
• Previously secondary generalized seizure |
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Term
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Definition
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Term
Seizure Classifications
• Focal motor involvement: |
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Definition
• Often a subclassification of focal aware or
impaired awareness
• Focal motor seizure:
- Some type of movement present
- Twitching, jerking, stiffening movements
- Automatisms: licking lips, hand rubbing, walking
• Focal nonmotor seizure:
- Initial symptoms include changes in sensation,
emotions, or thinking |
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Term
Seizure Classifications
• Generalized motor involvement: |
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Definition
- Generalized motor seizure:
• Generalized tonic-clonic: stiffening (tonic) and jerking (clonic)
• Other motor types (can be combinations of these): • Clonic (jerking) • Tonic (stiffening) • Myoclonic (twitches) • Atonic (loss of tone)
- Generalized nonmotor seizure:
• Absence: brief changes in awareness, staring
• Often confused with daydreaming |
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Term
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Definition
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Term
Seizure Characteristics: Focal
• Focal aware: |
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Definition
• Symptoms fully dependent on the location of cortex that is
disrupted
- Occipital cortex: flashing lights
- Motor cortex: rhythmic jerking contralateral side (Jacksonian march)
- Parietal cortex: special perception changes
- Frontal cortex: alterations in speech
• Early symptoms of focal aware seizure, auras, can go
unreported for months to years
• Ictal: awareness maintained
• Postictal: usually immediate return to baseline, can have a
temporary neurologic deficit (Todd paralysis) |
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Term
Seizure Characteristics: Focal
• Focal impaired awareness: |
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Definition
• Impairment at onset or as seizure progresses
• Most common seizure type in adults with epilepsy
• Appear awake but not in contact with surroundings
• Remain motionless or experience automatisms
• Ictal: Typically <3 minutes, unaware
• Postictal: somnolence, confusion, HA for hours |
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Term
Seizure Characteristics: Focal
• Focal aware and focal impaired awareness
can -> bilateral tonic-clonic seizures |
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Definition
• Slow progression: initial focal symptoms à bilateral
tonic clonic
• Rapid progression: appear similar to generalized
tonic-clonic with absence of distinct initial focal
symptoms
-Most first event unprovoked generalized seizures
are actually bilateral tonic-clonic seizures |
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Term
Seizure Characteristics: Generalized
• Generalized tonic-clonic: |
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Definition
Most common type of generalized seizures
• Abrupt loss of consciousness -> muscle
stiffening -> muscle jerking -> slow awakening
with confusion and agitation
• Ictal: unaware
• Postictal: confusion, agitation |
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Term
| phases of tonic clonic seizures |
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Definition
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Term
Seizure Characteristics: Generalized
• Absence (nonmotor): |
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Definition
• Typically onset in childhood
• Last 5–10 seconds, occurring in clusters
- If >10 seconds à automatisms may occur
• Sudden staring (appears like daydreaming) with
impaired consciousness |
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Term
Seizure Characteristics: Generalized
• Clonic: |
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Definition
| • Rhythmic jerking typically in arms, neck, and face |
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Term
Seizure Characteristics: Generalized
• Myoclonic: |
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Definition
| • Sudden, brief contractions typically in arms |
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Term
Seizure Characteristics: Generalized
• Tonic: |
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Definition
| • Sudden muscle stiffening |
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Term
Seizure Characteristics: Generalized
• Atonic: |
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Definition
• A.k.a. drop seizures
• Sudden loss of tone, typically legs à collapse
• High level of risk for head injuries |
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Term
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Definition
Seizure lasting longer than five minutes or
• ≥2 seizures without interictal return to baseline |
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Term
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Definition
• Accurate description from patient only usually
available for focal aware seizures
• Fall? Witnessed?
• Postictal period?
• Prior events
• Diagnostic delays common for nonconvulsive events
• Precipitants or triggers
• Change in medications
- Generalized tonic-clonic > focal
• Family history
- Absence and myoclonic can be inherited |
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Term
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Definition
• Typically unrevealing
• Helpful to rule out differentials
- I.e., weakness, hyperreflexia, Babinski -> contralateral structural lesion
• Injuries secondary to episode
- Head injuries, tongue lacerations |
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Term
Patient Evaluation
• Diagnostic studies: |
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Definition
• CBC
• CMP
• UA
• Toxicology
• After generalized tonic-clonic seizures
typically see elevation of:
- CPK, cortisol, WBCs, LDH
- Nonspecific and not very helpful to diagnose
• ECG
- Cardiogenic syncope à secondary hypoxic seizure
- Identify possible causes of syncope (long QT)
• EEG (electroencephalogram)
- Essential for diagnosis but timing can be tricky
- Immediately following event may be impacted by medication
use
- Routine EEG with epileptiform abnormalities à greater risk
of repeat event
-Normal EEG does not rule out epilepsy • Many EEG findings are nonspecific
• Lumbar puncture
- Only if concerned about CNS related acute infectious or
meningeal process like leptomeningeal CA
- Always image first to rule out space occupying brain lesion
• Neuroimaging
- Performed for all first seizure patients
- MRI preferred over CT
- Emergent if intracranial lesion suspected, head trauma,
persistent altered mental status • Typically CT first then MRI if stable
- Deferred outpatient MRI if rapid return to baseline and
normal neurologic exam with normal CT in ED |
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Term
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Definition
• Most seizures remit spontaneously within
two minutes
- Therefore, benzodiazepines or other antiseizure
medications aren’t needed
- IV access typically secured by paramedics or
in ED, so ready if recurs or is prolonged |
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Term
| • Immediate intervention for status epilepticus: |
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Definition
• BLS and 100% O2
• Lorazepam 0.1mg/kg IV at max of 2mg/min
• Wait one minute and determine if additional doses
• Alternative: initial 4mg fixed loading dose
• No definitive max dose
• If glucose <60mg/dL: thiamine 100mg IV and
dextrose 50% dextrose in water 50mL IV bolus
• Followed by fosphenytoin or phenytoin infusion for
continued seizure control
• If IV access not available, midazolam 10mg IM can be
substituted for lorazepam |
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Term
| • Long-term anti-seizure therapy: |
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Definition
• Case by case basis
• 1/3 of patients with first unprovoked seizure will have
recurrent seizure within 5 years
• >60% chance of recurrent seizure within 10 years if
(meeting ILAE criteria for epilepsy after initial event)
- Epileptiform abnormalities on interictal EEG
- Remote symptomatic cause (brain tumor, malformation, or
prior CNS infection)
- Abnormal neurologic examination
- First seizure occurred during sleep |
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Term
Seizure Management
• Long-term treatment more likely to be
necessary if: |
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Definition
• Two or more seizures
• Unproved episode
• History of remote symptoms |
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Term
Seizure Management
• Focal: |
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Definition
• Carbamazepine (Tegretol)
• Lamotrigine (Lamictal)
• Oxcarbazepine (Trileptal)
• Levetiracetam (Keppra) |
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Term
Seizure Management
• Generalized |
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Definition
• Valproic acid (Depakene)
• Topiramate (Topamax)
• Lamotrigine (Lamictal)
• Levetiracetam (Keppra) |
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Term
Seizure Management
• Absence: |
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Definition
| • Ethosuximide (Zarontin) |
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Term
Seizure Management
• Patient education: |
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Definition
- Be aware of common triggers:
• Sleep deprivation
• Stress
• Alcohol
- Avoid unsupervised dangerous activities:
• Swimming
• Operating machinery (employment medical history?)
- Driving:
• State laws vary
• Almost all require some period of abstinence following
seizure or loss or altered consciousness |
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Term
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Definition
• Transient loss of consciousness (TLOC)
caused by period of inadequate cerebral
nutrient flow
- Typically 8–10 seconds
- Most often due to abrupt drop in systemic BP
- By definition must be spontaneously selflimited
• Presyncope: symptoms present but never
true LOC
• Loss of postural tone (always seen with
LOC) -> collapse -> possible secondary
injury
• Complete and rapid full recovery (typically
1–2 minutes maximum) |
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Term
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Definition
• Four categories:
1. Reflex syncope (neutrally-mediated reflex
syncope)
2. Orthostatic syncope
3. Cardiac arrhythmias
4. Structural cardiopulmonary disease
• Must rule out:
- Seizure, sleep disturbances, accidental falls,
conversion disorders |
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Term
| syncope high risk -> admit |
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Definition
| arrythmia-related w ECG changes, cardiac ischemia-related, cardiovascular syncope |
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Term
Syncope Presentation
• Classic prodromal symptoms: |
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Definition
• Lightheadedness
• Changes in temperature
• Sweating
• Palpitations
• Nausea
• Visual blurring
• Diminution of hearing
Absence of prodromal symptoms is usually
associated with cardiac causes |
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Term
Syncope Evaluation
• History: |
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Definition
• Witnessed?
• Prodromal symptoms?
• Duration of LOC?
• Changes in breathing?
• Changes in physical
movements?
• History of structural heart
disease? Neurologic
conditions? DM? Intoxication?
• Change in medication?
• Family history of sudden death
<40 years of age? |
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Term
Syncope Evaluation
• Exam: |
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Definition
• Vitals, including orthostatic and
bilateral BP
• Complete cardiac and
neurologic exam
• ECG |
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Term
Syncope Evaluation
• Follow depending on suspected
etiology: |
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Definition
• Ambulatory ECG
• Echocardiography
• Carotid sinus massage (not
highly recommended)
• Neurological testing rarely
indicated (possibly if PD is
concern) |
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Term
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Definition
• Management is driven by underlying
cause
• Patient education for avoiding dangerous
events, pull over if driving when prodromal
symptoms present |
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