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 1 st 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

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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

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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

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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

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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

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Phenobarbital

 20 mg / kg at 50 mg /min   Should be given in seizures cont. after phenytoin loading This + BDPZ  Depression  produces significant Respiratory may require intubation  Once loading dose admin: serum lvl 20 ug/ml  Monitors (ECG/BP): ▪ arrythmias, ▪ HypoTN

  Long-term drug therapy  Phenytoin (Dilantin) + carbamazepine

treatments

(Tegretol) + valproic acid  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 -- first-line  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.

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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. Type of seizure  b. Age at time of onset  c. Cause of seizures (if known)  d. Medications  e. Frequency of physician visits (name and phone number)  f. Degree of seizure control  g. Frequency of seizures  h. Date of last seizure  i. Known precipitating factors  j. 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.

Drowsiness  b.

Slow mentation  c.

Dizziness  d.

Ataxia  e.

Gastrointestinal upset  f.

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.

Consider placing a ligated mouth prop at beginning of procedure  b.

Chair back in supported supine position Manage the seizure  a.

Clear area  b.

Turn patient to side (to avoid aspiration)   c.

Do not attempt to use padded tongue blade  d.

Passively restrain After the seizure  a.

Examine for traumatic injuries b.

Discontinue treatment, arrange for patient transport