Download Seizure Disorders - Huntington Beach Oral and

By David R. Telles
4/11/08
Department of Oral and Maxillofacial Surgery
University of Illinois at Chicago


Approximately 10% of the population will have
at least one epileptic seizure in a lifetime
Incidence: 0.5%.1 Seizures MC during childhood
 Up to 4% of children at least one seizure in the 1st 15
years of life
 outgrow the disorder


4 in 1000 children do not outgrow the disorder
common in the elderly 134 per 100,000
 Cerebrovascular disease MC factor underlying
seizures

Categories
 Generalized Convulsive Status Epilepticus
▪ AKA tonic-clonic
 Petit Mal – aka partial seizures or absence seizures
 Myoclonic
 Tonic
 Atonic

Onset
 changes in body movement or function, sensation, awareness, or
behavior
 last from a few seconds to status epilepticus (continuous seizure
that will not stop without intervention)
 sudden and involuntary contraction of a group of muscles
 can also be as subtle as numbness of a part of the body
 loss of memory
 sparkling or flashes
 sensing an unpleasant odor
 a strange epigastric sensation or a sensation of fear
 classified as motor, sensory, autonomic, emotional or cognitive
Warning to the sufferer that a full tonic-clonic seizure is
about to occur “an aura”
 Symptoms experienced by a person during a seizure
depend on where in the brain the disturbance in
electrical activity occurs
 Tonic-clonic seizure - cry out, lose consciousness and
fall to the ground, and convulse, often violently
 Complex partial seizure -- appear confused or dazed
and not be able to respond to questions or direction
 Absence seizure -- rapid blinking or a few seconds of
staring into space.


Arteriovenous malformation (AVM)
 seizures, headaches, and brain hemorrhages.
 Dx: MRI






Head injury may cause non-epileptic post-traumatic
seizures or post-traumatic epilepsy, in which the
seizures chronically recur.
Intoxication with drugs
Drug toxicity (e.g. aminophylline or local anaesthetics)
Normal doses of certain drugs that lower the seizure
threshold, such as tricyclic antidepressants
Infection (e.g. encephalitis or meningitis)
Fever -- febrile convulsions








Metabolic disturbances (i.e. hypoglycaemia,
hyponatremia or hypoxia, uremia, anoxia)
Withdrawal from drugs (anticonvulsants and sedatives
such as alcohol, barbiturates, and benzodiazepines)
Space-occupying lesions in the brain (abscesses,
tumors)
Seizures during (or shortly after) pregnancy can be a
sign of eclampsia.
Binaural beat brainwave entrainment may trigger
seizures in both epileptics and non-epileptics
Stroke
MS
Medications – which lower seizure threshold

2007 evidence-based review
 American Academy of Neurology and American
Epilepsy Society
 (EEG, brain wave activity) and brain imaging CT
scan or MRI scan in the work-up of adults
presenting with a first apparently unprovoked
seizure
▪ Not indicated for acute events/management
 Blood tests, lumbar puncture or toxicology
screening


Continuous or intermittent generalized
convulsive seizure activity lasting 10 mins w/o
recovery of consciousness
Acute management




O2 supplementation via bag/mask
Administration of Anticonvulsants
VS, pulse Ox, continuous ECG
IV line started
▪ Admin 100 mg Thiamine followed by 50 ml of 50% dextrose
 Lab Analysis: Glucose, Electrolytes, Ca, Mg, BUN,
creatinine, Anti-epileptic drug lvls, CBC/urinalysis, Tox
screen

Parenteral Anticonvulsants
 Stops seizures most rapidly – reserved for pt with
persistent generalized convulsive seizures due to
Aes
 Preferred = oral route
 Commonly used
▪ Lorazepam or Diazepam
▪ Phenytoin
▪ Phenobarbital

Lorazepam
 0.1 mg/kg
 At 2 mg/minute up to 4 mg

Diazepam
 0.2 mg/kg
 5 mg/min up to 10 mg
Stops seizures quickly in most pts
Short duration of action necessitates
anticonvulsant maintenance
 Respiratory Depression may necessitate
endotracheal intubation



Phenytoin
 Preferred maintenance anticonvulsant (w/ BDZP)
 Can be admin via Parenterally as Phenytoin




Sodium or Fosphenytoin
Loading dose of SE: 20 mg/ kg
Max Infusion rate: 50 mg / min
Monitor BP and Cardiac Rhythm: for HypOtension
and Heart block
Contraindicated in heart block

Phenobarbital
 20 mg / kg at 50 mg /min
 Should be given in seizures cont. after phenytoin
loading
 This + BDPZ  produces significant Respiratory
Depression  may require intubation
 Once loading dose admin: serum lvl 20 ug/ml
 Monitors (ECG/BP):
▪ arrythmias,
▪ HypoTN
 Long-term drug therapy
 Phenytoin (Dilantin) + carbamazepine (Tegretol) + valproic acid -- first-line
treatments
 reduce the frequency of seizures by
 elevating the seizure threshold of motor cortex neurons
 depressing abnormal cerebral electrical discharge
 limiting the spread of excitation from abnormal foci
 efficient at blocking sodium or calcium channels of the motor neurons
 Phenobarbital = second-line drug
 can induce hepatic microsomal enzymes that can increase metabolism of concurrently used drugs
 Several antiseizure medications cause
 Drowsiness
 Sedation
 Ataxia
 weight gain
 cognitive impairment
 hypersensitivity reactions.11
 Drug therapy continued in children until a 1- to 2-year seizure-free period
is obtained or until around age 16 years
 Vagus nerve stimulation (VNS)
 reserved for patients with unsatisfactory seizure control
with several medications
 option for some before brain surgery
 similar to an implantable cardiac pacemaker -- a
subcutaneous pulse generator is implanted in the left chest
wall + delivers electrical signals to the left vagus nerve
through a bipolar lead
 provides direct projection to regions in the brain potentially
responsible for the seizure
 used in combination with antiepileptic medications.


After SE Tx-ed and causative factor IDed and
Tx-ed …
Anticonvulsive Drugs maintained
 Except BZDPs
 Phenytoin 4-7 mg / kg / day
 Phenobarbital 1-5 mg / kg / day

Conversion to oral regimen tailored –
typically pts are managed on 1 oral
antiepileptic med

Identification of patient by history










a.
b.
c.
d.
e.
f.
g.
h.
i.
j.
Type of seizure
Age at time of onset
Cause of seizures (if known)
Medications
Frequency of physician visits (name and phone number)
Degree of seizure control
Frequency of seizures
Date of last seizure
Known precipitating factors
History of seizure-related injuries
Provide normal care—well-controlled seizures pose no management
problems
 If questionable history or poorly controlled seizures, consultation with
physician before dental treatment—may require modification of
medications


Be alert to adverse effects of anticonvulsants






a.
b.
c.
d.
e.
f.
Drowsiness
Slow mentation
Dizziness
Ataxia
Gastrointestinal upset
Allergic signs (rash, erythema multiforme)
Patients taking valproic acid (Depakene) or carbamazepine (Tegretol) may have
bleeding tendencies because of platelet interference—order pretreatment bleeding
time; if grossly abnormal, consultation with physician
 Be prepared to manage grand mal seizure



 a.
 b.
Consider placing a ligated mouth prop at beginning of procedure
Chair back in supported supine position




Clear area
Turn patient to side (to avoid aspiration)
Do not attempt to use padded tongue blade
Passively restrain
Manage the seizure
a.
b.
c.
d.
After the seizure
 a.
 b.
Examine for traumatic injuries
Discontinue treatment, arrange for patient transport