Glossary of Neuro: Seizures

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Epidemiology of Epilepsy
0.5% of population have Epilepsy

1.5% to 5% suffer a single seizure at some time

bimodal incidence (tends to effect the very young and very old)
Etiology of Epilepsy
-cause is identifed in only 25-33% of cases
Risk of sezire recurrance after 1st seizure
lower rates from hosptial estimates
higher rates from population-based studies
Percentage of epilepsy patients that can be controlled with drugs
Definition of Seizures
discrete clinical events that reflect a temporary physiologic dysfunction of the brain
characterized by excessive and hypersynchronous discharge of cortical neurons
Defintion of Epilepsy
a chronic disorder or group of disorders characterized by seizures that usually recur unpredictably
Status Epilepticus
seizures recurring frequently enough to produce a fixed and enduring epileptic condition lasting at least 30 minutes
refers to the degree of awareness and/or responsiveness of the patient to externally applied stimuli
refers to the ability of the patient to carry out simple commands of willed movement
refers to the patient's conact with events during the period in questions and it's recall
refers to seizure
-defined as more or less coordinated adapted involuntary motor activites occurring during the state of clouding of consciousness either in the course of, or after, and epileptic seizure
-a continuation of an activity that was going on when seizure occured OR a new activity developed in association with the ictal impairment of consciousness
examples of automatisms
eating automatisms: chewing, lip smacking

gestural automatisms: fumbling of clothes, scratching, drawing patterns with the feet
-portion of the seizure which occurs before consciousness is lost and for which memory is retained afterwards
-is a simple partial seizure
In simple partial sezures, the aura is...
the whole seizure
In complex partial seizures, the aura ....
precedes the complex partial seizure
International Classification of Seizures
-1981 by International League Against Epilepsy
-Scheme based on classifying the type of sezure based on where in the brain the seizure originates and spreads
Categories of Seizures
1. Partial
2. Generalized
3. Unclassified
Partial Seizures
arise in part of one cerebral hemisphere and are accompanied by focal electroencephalographic abnormalities
Generalized Seizures
those with clinical and electroencephalographic manifestations that indicated simultaneous involvement of both cerebral hemizpheres from the onset
-neonatal seizures
-rythmic eye movement disorders
Subtypes of Partial Seizures
1. Simple partial seizures
2. complex partial seizures
3. partial seizures secondarily generalized
Simple Partial Seizures
consciousness is preserved (pt is responsive and aware)
Complex Partial Seizures
consciouness is impaired
Partial seizures secondarily generalized
beggin as partial seizure (either simple or complex) and then spread to involve both cerebral hemispheres
Subtypes of Simple Partial Seizures
1. with motor sx
2. with somatosensory or special sensory sx
3. with autonomic sx
4. with psychic sx
Simple partial Seizures with motor symptoms
-any portion of body may be involved
-depends on site of origin of the attack in the cortical motor strip

e.g. jerking
"Jacksonian march"
simply partial seizure with motor symtpoms where jerking progress up the limb (like a march)
Simple parital seizures with somatosensory or special sensory symptoms
-arise from areas of the cortex with symptoms referable to the cortical regions affected

sensory cortex: pins and needles in contralateral area of body
visual cortex: flashing lights in contralateral visual field
olfactory cortex: unpleasant odors
Simple Partial Seizures with autonomic symtoms
-pupil dilation
Simple partial seizures with psychic symptoms
dysmestic: distorted memory experience such as "deja vu"

affective: attacks of sensations of extreme pleasure, fear, terror, rage, etc.
Two ways the a complex Partial seizure begins
1. begins as a simple partial sezure and progresses to impairment of consciousness (the aura is the simple parital seizure preceding the impairment)

2. begins with impairment of consciousness at the onset
Do complex partial seizures have post ictal condusion?
Yes, there IS Post ictal Confusion
3 ways that a partial seizure secondarily generalized progresses
1. simple partial seizure evolves into generalized seizure
2. complex partial seizure evolves into generalized seizure
3. simple partial seizure evolves into complex partial seizure evolves into generalized seizure
Subdivisons of Generalized Seizures
1. Absence seizures
2. Atypical absence seizures
3. myoclonic seizures
4. clonic seizures
5. tonic seizures
6. tonic clonic seizures
7. atonic seizures
Absence seizure
-generalized seizure
-"petit mal"
-sudden onset, interuption of ongoing activities, blank stare, lasting for a few seconds, immediate return to normal activities (sudden offset)
Absence seizure EEG
3 cycles per second generalized spike and wave pattern
Atypical Absence seizure
-generalized seizure
-pts are often mentally retarded
-onset and offset more difficult to determine
Atypical Ansence seizure EEG
1.5 to 2 cycles per second generalized spike and wave ("slow spike and wave")
Myoclonic seizure
-generalized seizure
-sudden, breif shock-like contractions
-may be generalized or confined to face or trunk or extremity
Clonic seizure
-generalized seizure
-repetitive clonic jerking of affected areas of body
Tonic seizure
-generalized seizure
-muscular contraction fixing the trunk, neck, and limbs in some strained position (often extended)
Tonic clonic seizure
-generalized seizure
-"grand mal"
-sudden sharp tonic contraction of muscles
-Tonic and Clonic phase
Tonic Phase of tonic clonic sezure
-resporatory muscles: stridor, cry or moan
-trunk and extremity muscles: fall to ground, pt lies rigid, cyanosis
-Sphincter muscles: urinary incontenence
Clonic phase of tonic clonic seizure
-Repiratory muscles: small gusts of grunting aspirations
-trunk and extremity muscles: clonic movements

-post ictal phase: deep respiration and slow return to consciousness
Is there a post-ictal phase for tonic clonic seizures?
Yes, post ictal phase is present

deep respirations and slow return to consciousness
Atonic Seizure
-generalized seizure
-sudden diminution of tone
-Fragmentary: head drop or drooping arms
-axial musculature: patient falls to ground ("drop attacks")
managment strategies for patients with seizures
1. antiepileptic drugs

2. surgical resection of the epileptogenic zone
-start the drug thought most likely to be effective
-if seizures recur, inc dose until seizures abate
-if SEs occur and seizures have not abated, then the therapeutic window for that drug has been reached so try starting another drug thought likely to be effective and TAPER OFF 1st DRUG
Rational therapy
-treat with more than one drug with differing mechanisms of action
-only if monotherapy cannot control seizures!!
Pharm: First Choice for Partial Onset Seizures
Pharm: Second Choice for Partial Onset Seizures
-valproic acid
Pharm: Adjuntive for partial Onset Seizures
Pharm: First Choice for Tonic Clonic Seizures
-Valproic Acid
Pharm: Second Choicefor Tonic Clonic Seizures
Pharm: Adjunctives for Tonic Clonic Seizures
Pharm: First Choice for Tonic, Clonic, Atonic seizures
-Valprioc Acid
Pharm: Second Choice for tonic, clonic, atonic seizures
Pharm: Adjunctive therapy for tonic, clonic, atonic seizures
Pharm: First Choice for absence seizures
-valproic acid
Pharm: Adjunctive for absence seizures
Pharm: First choice for myoclonic seizures
-valproic acid
Pharm: Adjunctive for myclonic seizires
Managemement of Status Epilepticus: Step 1
-assess airway, breathing, circulation
-admin O2, monitor cardiac rhythem, oxygen saturation and vitals
-bedside glucose test
-draw blood for AED levels, CBC, electrolytes, calcium and magnesium, glucose and toxicology screen
-administer thiamine 100 mg and detrose 50% 50 ml IV
-obtain hx and perform exam
Managemement of Status Epilepticus: Step 2
-admin IV lorazepam
0.1 mg/kg in adults
0.05 mg/kg in children
-OR admin diazepam
0.25 mg/kg in adults
0.1 to 1 mg/kg in children
-Repeat after 10 minutes if seizures persist
-administer fosphenytoin 20 PE (phenytoin equivalents)/jg load (up to 150 PE/min)
-If seizures persis, give fosphenytoin 5-10 PE/kg to total dose of 30 PE mg/kg or serum concentraiton of 30 ug/ml
Managemement of Status Epilepticus: Step 3
-intubate, place arterial line, and draw arterial blood gas and phenytoin level
-consider IC phenobarbital 20 mg/kg (110 mg/min or 3 mg/kg/min in children)
Managemement of Status Epilepticus: Step 4
-consider pharm coma wihth pentobarbital 5-8 mg/kg load, followed by continuous infusion of 2-4 mg/kg/hr titrated to burst supression for 6-48 hrs
-midazolam 0.2 mg/kg load followed by continuous infusion beginning at 1 ug/kg/min increasing by 1 ug/kg/min every 15 to 30 min as needed to a max rate of 1o ug/kg/min

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