Transcript Seizures - QStation

Seizures
Garrett Preston Clark, D.O.
Masters of Medical Education
Candidate 2008
What is a Seizure???
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Paroxysmal neurologic event caused by
abnormal synchronous discharges from
populations of cortical neurons.
Epilepsy is a condition in which pts have
unprovoked, recurrent seizures.
The key 1st step is to make the classification as
to whether or not the initial seizure activity is
generalized or focal at onset.
First Step  Classify
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Requires a full history from the patient and
those who have witnessed the actual seizure
activity.
Good idea for neurology referral, but PCP can
manage subsequent Sz’s.
Ask about Sz triggers (e.g. EtOH, lack of
sleep, internship & residency, etc).
CLINICAL PEARL:
Evaluate patients after their 1st seizure for
mass lesions before the initiation of
treatment for epilepsy !
Seizure Types:
1.
2.
3.
4.
5.
Partial (or focal)
Primary (idiopathic) Generalized
Tonic-Clonic (Grand Mal)
Absence (Petit Mal)
Infantile Spasms (West Syndrome)
Clinical Pearl:
Head trauma is a chief cause of focal seizures
in young adults, as opposed to brain tumor
or vascular disease in older patients.
Partial seizures:
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Visible manifestations ex: limb jerking
Subjective (perceived only by the patient….aka,
auras) ex: epigastric discomfort, fear, or an
unpleasant smell.
Partial Seizures:
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Arise from a discrete region in ONE cerebral
hemisphere.
DO NOT lead to LOC, UNLESS they
secondarily generalize.
May be simple (SPS) or complex (CPS)
Partial Seizures:
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SPS may be immediately followed by CPS
CPS: usually have clouding of consciousness,
staring, and repetitive motor behaviors (e.g.
swallowing, chewing, or lip smacking).
After a CPS, patient may have confusion, or
throbbing headache.
Patients often have no recollection.
Some Old Guy ???
Simple Partial Seizures (SPS):
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The Motor  Jacksonian march (named after
John Hughlings Jackson) = progressive jerking
of successive body regions.
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Psychic Features  Fear, Déjà vu, a glitch in the
Matrix!
http://www.dinf.ne.jp/doc/english/global/david/dwe002/dwe002g/dwe00231g24.gif
Complex Partial Seizures (CPS):
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Temporal lobe involvement  70-80%
Impaired level of consciousness.
Auditory and visual hallucinations
Lip smacking, chewing.
Disoriented and confused.
Sx’s can mimic schizophrenia or acute psychosis.
BOTH CPS and SPS may evolve into secondary
generalized tonic-clonic (grand mal) Sz’s!
Temporal Lobe Epilepsy:
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The most common cause of SPS and CPS is
temporal lobe pathology 2ndary to
abnormalities of the hippocampus.
Sclerosis or calcification is seen on imaging.
The classic auras such as odd smells, sounds, or
tastes, are all associated with temporal lobe
epilepsy.
Partial Seizures Treatment:
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Treat any underlying cause.
Phenytoin, oxcarbazepine, tegretol,
phenobarbital, or valproic acid can be used as
montherapy for recurrent partial Sz’s.
Phenobarbital is 1st line anticonvulsant in
children.
Surgical options for intractable temporal Sz’s 
anterior temporal lobectomy.
Partial Seizures Treatment:
Wada Testing (not Watto):
Prior to surgery, a brain-numbing agent (sodium
amytal) is injected into the anterior temporal
lobe through the MCA to identify any functional
deficits which would preclude resection.
Focal Seizure EEG:
The electroencephalogram records the spike and wave activity that is occurring in the right parietal region. Courtesy of Shahram Khoshbin, MD.
Clinical Pearl:
Seizure disorder is a clinical diagnosis NOT
an EEG diagnosis! A normal EEG does
NOT rule out seizure disorder.
Primary (idiopathic) Generalized:
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Involves BOTH cerebral hemispheres.
Leads to sudden LOC.
Usually withOUT aura.
Followed by a period of postictal confusion.
Two most common types are tonic-clonic
(Grand Mal) and absence (Petit Mal).
Tonic-Clonic:
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Tonic phase = stiffening of the extremities, is
often associated with a guttural cry 2ndary to
contractions of the expiratory musculature.
Clonic phase = rhythmic jerking of the
extremities.
 Typically, there is associated urinary
incontinence, tongue biting, and confusion
(postictal)
Generalized seizures
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The first clinical and EEG changes indicate that
large parts of both hemispheres of the brain are
involved at the onset of the seizure.
Almost always impaired consciousness.
Common subtypes are:
tonic-clonic seizures (grand mal)
 absence seizures (petit mal)
 myoclonic seizures.
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Generalized  Tonic-Clonic
(Grand Mal):
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Begin suddenly with tonic extension of the back
& extremities.
Subsequently continuing on with 1-2 minutes of
repetitive and symmetric clonic movements.
Marked by incontinence & tongue biting.
May appear cyanotic during the ictal period.
Consciousness slowly regained during the
postictal period.
Postictal State ???
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Period of transition from the ictal state back to
the individual's normal level of awareness &
function.
Signifies a recovery period for the brain.
May last from seconds to minutes to hours.
Generalized  Tonic-Clonic
(Grand Mal):
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Postictally, the patient may complain of muscle
aches and/or headaches.
Keep brain stem ischemia, pseudoseizures, and
dysrhythmias in your differential.
Generalized  Tonic-Clonic
(Grand Mal) Treatment:
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Treat underlying cause.
Valproate is 1st line for primary (idiopathic)
generalized tonic-clonic Sz’s.
Can use Lamotrigine or topiramate as adjunctive
therapy
If secondarily generalized tonic-clonic, use same
Tx as for focal (partial) Sz’s.
Generalized Seizure EEG:
The electroencephalographic recording of the onset of a generalized tonic-clonic seizure is illustrated. Courtesy of Shahram Khoshbin, MD.
Absence (Petit Mal) Seizures:
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Begin in childhood.
Subside before adulthood.
Often, are familial.
Present with brief, often times unnoticeable
episodes of impaired consciousness.
Last 5-10 seconds, and can occur up to
hundreds of times per day.
Absence (Petit Mal) Seizures:
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Patients are usually amnestic durring and
immediately after the seizures.
Recall: “teacher observing a child daydreaming
or staring into space, during class time”.
Lip smacking and/or eye fluttering may occur
during the event.
No loss of muscle tone.
Absence (Petit Mal) Seizures:
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EEG shows 3-per-second spike-and-wave
discharges.
Ethosuximide is 1st line treatment.
May also use Valproic acid or zonisamide.
Typical 3-Hz spike & wave
discharges seen in absence epilepsy:
http://www.emedicine.com/neuro/images/Large/3105_27Slide2.jpg
Myoclonic Seizures:
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Consist of a myoclonic jerk, which is an
abrupt, brief, single contraction of a muscle
group producing a quick contraction movement.
Asynchronous, nonrhythmic, and multifocal
myoclonic jerks.
Most commonly seen with metabolic
derangements such as uremia or anoxic brain
injury.
Myoclonic Seizures:
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Juvenile myoclonic epilepsy = genetic cause of
myoclonic seizures.
Patient’s have “staring spells” or eye blinking
and chewing movements.
Subsequently develop myoclonic and tonicclonic seizures in adolescence.
May also experience myoclonic jerks when
entering or emerging from sleep.
Status Epilepticus 
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Seizure “badness” lasting > 30 minutes OR
recurrent seizures without return of normal
consciousness b/w seizures.
Seizure activity lasting > 5 minutes is unlikely to
remit spontaneously and carries risk of
permanent neuronal injury!
Szs lasting > 5 min are considered medical
emergencies & treated as if they were status
epilepticus.
Status Epilepticus Treatment
Guidelines:
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ABCs
Labs to check for metabolic abnls (glucose,
calcium, Na+)
Give thiamine and glucose
Benzos are 1st line for status epilepticus
Status Epilepticus Treatment
Guidelines:
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Lorazepam: 0.1mg/kg IV given at < 2mg/min.
Phenytoin or fosphenytoin should then be started
immediately, EVEN IF Szs terminate with lorazepam.
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Phenytoin: 20mg/kg IV at < 50 mg/min
Fosphenytoin: 20 mg/kg “pheytoin equivalents” IV at <150
mg/min.
If Szs persist, give 2nd load using an additional 5-10 mg/kg IV
load.
If Szs STILL continue, give pentobarbital, midazolam, or
propofol  usually requires EEG, mechanical vent, and
cardiac pressors.
Management Goals:
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Controlling seizures
Avoiding side effects of treatment
Maintaining or restoring quality of life
Treatment Review (Generalized):
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The “broad spectrum” anticonvulsants are
generally considered 1st line therapy for Tx of
primary generalized Szs (valproic acid,
topiramate, lamotrigine).
Beware that phenytoin and carbamazepine can
actually exacerbate seizures  try to avoid.
Best treatment for absence epilepsy 
ethosuximide.
Treatment Review (Partial):
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Phenytoin, valproic acid good choices.
Newer agents: gabapentin, levetiracetam,
lamotrigine, and topiramate also good.
Vagal nerve stimulation  MOA unclear, but
can decrease frequency of focal onset Szs by
25% in pts with medically refractory Szs.
Surgery  temporal lobectomy may have up to
50-75% of pts becoming seizure free!
FUN-ee-TOE-in
http://www.australianprescriber.com/upload/issue_files/2601_ging_02.gif
Anticonvulsant Side Effects:
Phenytoin
Carbamazepine
Valproate
Gum hyperplasia, peripheral
neuropathy, ataxia,
lymphoproliferative d/o,
SJS
Hyponatremia,
lymphopenia, SJS
Tremor, drowsiness, weight
gain, hirsutism,
thrombocytopenia, liver
failure
Driving Restrictions:
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States vary widely in driver licensing requirements for
patients with epilepsy.
The most common requirements are that patients be
free of seizures for a specified period of time and that
they submit a physician's evaluation of their ability to
drive safely.
A listing of individual state driving requirements can be
found on the Epilepsy Foundation Website at:
http://www.epilepsyfoundation.org/living/wellness/transportation/driverlice
nsing.cfm.
http://www.uptodateonline.com.lecomlrc.lecom.edu/online/content/topic.do?topicKey=epil_eeg/4878&selectedTitle=4~106&source=search_
result#37
Clinical Pearl:
Phenytoin and carbamazpine induce P-450 =
decreased level of other drugs, esp OCPs.
Counsel all female patients to consider other
means of birth control!
Clinical Pearl:
The use of anticonvulsant medications during
pregnancy are associated with increased risk
of birth defects, especially NEURAL TUBE
DEFECTS. Advise pts to take 0.4mg/day
folate and use single agent at lowest possible
dose.
THE END
References:
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http://www.medscape.com/content/2003/00/45/85/458594/artsin458594.fig26.gif
http://www.emedicine.com/neuro/images/Large/3105_27Slide2.jpg
www.medscape.com/.../art-sin458594.fig26.gif
http://www.uptodateonline.com.lecomlrc.lecom.edu/online/content/topic.do?topi
cKey=epil_eeg/4878&selectedTitle=4~106&source=search_result#37
http://www.uptodateonline.com.lecomlrc.lecom.edu/online/content/topic.do?topi
cKey=neuropat/4649&selectedTitle=1~150&source=search_result#3
First Aid for the Internal Medicine Boards (First Aid Series) (Paperback) by
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First Aid for the USMLE Step 2 (Paperback)
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