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Flashcards in Seizures Deck (29):


Seizure: sudden excessive disorderly discharge of neuronal activity in the brain

epilepsy: recurrent unprovoked seizures

convulsion: body muscles contract and relax rapidly and repeatedly, uncontrolled shaking of the body


Causes of Epilepsy?

Seizures beginning after age 20 are usually d/t what?

-genetic mutations
-hypersensitive neurons
-epileptogenic neurons (fire more intensely, more often, and with greater amplitude)

-highest in children, 2-5yrs and at puberty. *usually idiopathic or primary generalized epilepsy
-pts older than 50yo

Seizures beginning after age 20 are usually due to a focal process or metabolic derangement.


What are the most common causes of seizures:
-infancy childhood
-young adult
-middle age
-late life

infancey/childhood: fever, trauma, hereditary metabolic, injury, infections

adolescence: idiopathic

young adult: trauma, alcohol, drugs

middle age: cancer, alcohol, vascular dz (stroke)

late life: vascular dz, cancer, degenerative brain disorders

Other: sleep deprivation, fever, withdrawl


What is the difference between provoked and unprovoked seizures?

unprovoked seizures occur in the setting of persistent brain pathology whereas provoked are triggered by factors in an otherwise healthy brain.


exacerbations of seizure disorders are most commonly due to?

Mortality of epilepsy patients is d/t?

-medication noncompliance
-alcohol use

Mortality d/t underlying cause of epilepsy or sudden unexpected death of epilepsy (SUDEP; sudden, unexpected, nontraumatic, nondrowning)


Describe the Phases of seizures:

prodrome: feeling, sensation or changes in behaviors hours or days before seizure..deja vu, smell, sounds, taste, fear, HA, nausea

aura: 1st sx of a seizure and considered part of the seizure

Middle: "ictal phase"
-sx: loss of awareness, confusion, distracted/daydreaming, difficulty talking, unable to swallow, repeated blinking of the eyes, lip smacking or chewing movements.

Endin: "postictal phase"
Sx: slow to respond, sleepy, confused, injuries, HA, nausea


What are the types and Describe the difference between focal and generalized seizures?

-focal: limited to one cerebral hemisphere
--focal seizure without impairment of consciousness
--focal seizure with impairment of consciousness

Generalized: involves the cerebral cortex of both sides of the brain
--absence (petit mal)
--clonic, tonic, atonic
--tonic-clonic (grand mal)


Focal seizures w/o impaired consciousness can be categorized into what groups?

-Motor (jacksonian march; jerking stays on one side of the body, weakness, affected speech, coordination of actions)

-sensory: changes sense of smell and taste, clicking, ringing, pins/needles, floating in space, illusions, hearing voices

-autonomic: chest discomfort, changes in heart rate and breathing

-psychic: garbled speech, written language is off, trouble word finding


Features of focal seizure w/o impaired consciousness

-Todds paralysis (temporary, unilateral, 30min-36hrs)
-can progress to focal seiz w/ impaired consciousness to tonic clonic seizure


Focal seizure WITH impaired consciousness
-arise from which lobe?

what: produce unresponsiveness

arise from the temporal lobe

duration: 30seconds to 2 minutes

-same sx as focal w/o impairment, but these pts cannot talk to you.
-confusion and tiredness follow seizure for about 15mins


Generalized onset seizures: Absence

aka: "petit mal seizures"

What: non-convulsive epileptic events

Onset: typically occur in childhood and cease in adulthood.

Duration: onset and termination of attacks are abrupt

Consciousness: disturbances in consciousness; impairment so brief pt is unaware of it, lasts 10seconds


Generalized: Absence seizures:
-typical manifestations

-blank stare
-stop talking mid sentence
-mild clonic, tonic, or atonic components
-may have automatisms
-no postical period


Generalized: Atypical absence seizures

onset: gradual onset

duration: do not resolve abruptly

appearance: loss of muscle tone in neck and face. twitching of mouth...

consciousness: may not have an altered level of consciousness.


Generalized Myoclonic Seizure:
-what is this?
-most common time of occurrence?

What: rapid recurrent brief muscle jerks that can occur:
*may terminate into generalized tonic-clonic seizure

Most commonly occur shortly after waking or while falling asleep


Generalized: Atonic seizure
-characterized by what?

-aka: "drop attacks"

-characterized by sudden loss of muscle tone that may result in falls with self-injury


Febrile Seizures
-most common in who?
-temp is usually what?
- what are the 2 types?

Fever is most common cause of convulsions in children.

temperature is usually greater than 38 (100.4)

2 types: simple and complex

appearance: body becomes stiff and arms and legs twitch, lose consciousness, Simple lasts 15mins or less, complex lasts greater than 15minutes and happens multiple times in 24hr period

tx: IV lorazepam


Tonic Clonic Seizure

aka: Grand Mal

What: major motor seizure involving all extremities and characterized by sudden loss of consciousness.

Cause: may be primary arising from deep brain structure or represent a focal seizure with secondary generalization


tonic clonic seizure:
-what is tonic?
-what is clonic?
-describe the postictal scene
-postictal sx

Tonic: rigid, LOC, collapse, respiratory arrest
*this usually last less than 1 min*

Clonic: jerking
*may last 2-3 minutes*

-tongue and lips may be bitten
-urinary or fecal incontinence
-injury may occur

Postictal scene:
-may recover consciousness, drift into sleep, have further convulsions w/o recovery of consciousness between attacks (status epilepticus)
*have no memory of this

Posticatl sx:
-sore muscles


Secondary Generalized Seizure tonic clonic:
-what is this?

seizure that becomes generalized (spread to both sides of brain) after the initial event (focal seizure) has already begun.

dx: EEG and MRI

tx: carbamazepine


Post traumatic epilepsy
-most common causes

What: seizures post trauma, depends on degree of head injury

-penetrating head wounds
-cerebral contusion
-intracerebral hematoma
-unconsciousness or amnesia lastin more than 24hrs


Objectives of Seizure Dx

-determine if pt has epilepsy
-classify the seizure and type of epilepsy accurately and determine if the clinical data fit a particular epilepsy syndrome.
-identify, if possible, a specific underlying cause


What 4 conditions can mimic a seizure? What is each?

-REM behavior disorder: sudden arousals from REM sleep immediately followed by complicated often aggressive behaviors for which the pt is amnestic

transient ischemic attack

Transient global ischemia: short term memory deficit without other cognitiev or motor impairment



Seizure WOrk up:
-what is the most important dx test?
-what labs might you order?

-eeg; classifies seizures, identifies epileptic syndromes, helps in making therapeutic decisions

-MRI and CT as alternative

-anti-epileptic drug levels (AED)
-CMP, TSH, CBC, drug screen, glucose


Status Epilepticus:

WHat: any seizure lasting greater than 30 minutes or prolonged flurry of seizures without return to previous level of consciousness between seizures
*life threatening, especially if generalized tonic clonic status

-drug noncompliance or sudden withdrawl
-alcohol or drug withdrawl

-IV thiamine and glucosse
if the above are ineffective: phenobarbital or depacon ....if these fail; general anesthesia w/ ventilator assistance with NMJ blockade


All seizure tx
-provoked vs unprovoked

Provoked: tx underlying cause

1st seizure = no tx

2nd seizure = diagnosed with epilepsy and treat

other tx options:

-surgery; Anterior temporal lobectomy, corpus callostomy, amygdala-hippocampectomy

-ketogenic diet: high fat; low carb

-vagal nerve stimulator: implantation of device to stimulate vagus nerve to abort seizure



Seizure Tx
-3 basic MOA of medications

1.Voltage dependent Na or Ca channels:
-Na channel blockers effective for tonic-clonic and partial seizure
-Calcium channel blockers effective for absence seizures

2. Increasing inhibitory neurotransmission (GABA)

3. Decreasing excitatory neurotransmission (glutamate and aspartate)


Seizure Tx
-common medications & therapeutic plasma conc.
-serious SE

-Dilantin (phanytoin) (first line focal and generalized tonic clonic, plasma conc= 10-20mcg/mL)
*Na and Ca channel

-Tegretol (carbamazapine, 1st line for focal and generalized tonic clonic) Plasma conc = 4-12mg/L
--may cause toxic epidermal necrolysis & steven johnson syndrome
*Na channel

-Depacon (1st line focal, generalized tonic-clonic, absence, myoclonic, atonic, and atypical absence) --Plasma conc = 50-100mg/L
--BBW: liver dysfunction less than 2yrs old

-Phenobarbital (2nd line for focal and generalized tonic-clonic)
--plasma conc = 15-40mg/L
--SE: suicide
*GABA enhancement

-Zarontin (1st line for absence)
--plasma conc = 40-100mg/L
--SE: bone marrow suppression
*depress motor cortex
Category C

-Valium (diazepam)
-Ativan (lorazapam)


What are the common side effects of the seizure medications?

-memory difficulties
-cognitive or concentration difficulties


General guidlines for all seizure medications

-baseline Cr
-LFTs and CBC
-newer meds may be less sedating
-start low and slow; titrate up
-never stop abruptly
-dont stop one agent until another has been added
-can D/C drugs if pt is seizure free of 3 years
-pregnant women with epilepsy should continue their seizure medication