Epilepsy
Syndrome of CNS dysfunction.
Manifested in many different ways.
Most common chronic neurologic illness.
Cause by excessive electrical activity of neurons in cerebral cortex.
Chronic, recurrent pattern of seizures.
Seizure
Brief episode of abnormal electrical activity in nerve cells of the brain, may or may not lead to convulsion.
Convulsion
More sever seizure.
Involuntary spasmodic contractions of any or all voluntary muscles throughout the body, including skeletal and facial and ocular muscles.
Primary Epilepsy
Idiopathic:
Cause cannot be determined.
More than 50% of epilepsy cases.
May have genetic predispositions.
Secondary Epilepsy
Symptomatic:
Distinct cause is identified:
Trauma, infection, cerebrovascular disorder.
Chief cause in infants and children is related to developmental defects, metabolic disease and injury at birth.
In adults, acquired brain disorder is major cause.
Generalized-onset Seizures
Formerly known as grand mal seizures.
Neuronal activity originating simultaneously in gray matter in both hemispheres.
Several subtypes:Tonic-Clonic, Tonic, Clonic, Atonic (drop attacks), Myoclonic, absence & infantile spasms.
Mostly seen in children.
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Partial-onset Seizures: Simple
Formerly known as petit mal seizures.
Brief loss of awareness (blank stare), no loss of consciousness.
Motor symptoms commonly at face, arms or leg.
Hallucinations.
Autonomic nervous system responses.
Personality changes.
Partial-onset Seizures: Complex
Impaired consciousness.
Memory impairment.
Behavioral effect, also see purposeless behaviors.
Aura, chewing, swallowing, unreal feelings.
Tonic, clonic or tonic-clonic seizures.
Partial-onset Seizures: Secondary generalized tonic-clonic seizure
Partial onset seizures that progress.
Occurs in up to 40% of patients.
Postictal confusion.
Unclassified Seizures
Seizures that do not fit into any other category.
Status Epilepticus
Multiple seizures occurring without recovery between.
Can lead to hypotension, hypoxia, and cardiac dysrhythmias, which can lead to brain damage and death.
Febrile seizures can progress to this.
Antiepileptic Drugs (AEDs)
Also known as anticonvulsants.
Goals of therapy:
To control or prevent seizures while maintaining a reasonable quality of life.
To minimize adverse effects and drug-induced toxicity.
AED therapy is usually lifelong.
Patients who are seizure free for 1 to
Mechanism of Action
AED therapy must:
Prevent generation and spread of excessive electrical discharge from abnormally functioning nerve cells.
Protect surrounding normal cells.
Exact mechanism of action is not known.
AEDs are thought to alter movement of sodium, potassium, a
Mechanism of Action: Overall Effect
Neurons are stabilized.
Neuron hyperexcitability is decreased.
Spread of excessive nerve impulses is decreased.
Antiepileptic Drugs: Indications
Prevention or control of seizure activity.
Long-term maintenance therapy for chronic, recurring seizures.
Acute treatment of convulsions and status epilepticus.
Other uses.
Antiepileptic Drugs: Adverse Effects
Numerous adverse effects - vary per drug.
Adverse effects often necessitate a change in medication.
Black box warning as of 2008:
Suicidal thoughts and behavior (twice the risk).
Long-term therapy with phenytoin may cause gingival hyperlasia, acne, hirsut
Types of Antiepileptic Drugs
Barbiturates, such as phenobarbital (Luminal).
carbamazepine (Tegretol).
valproic acid (Depakene).
felbamate (Felbatol).
Hydantoins, such as phenytoin (Dilantin) and fosphenytoin.
Succinimides, such as ethosuximide (Zarontin).
Benzodiazepines (clonazepam
Nursing Implications: Assessment
Health history, including current medications.
Drug allergies
Renal and liver function studies, CBC
Baseline levels
Baseline vital signs
EEG, MRI, CT scans
Baseline Neurologic exam
Secure airway, breathing and circulation during seizure activity.
Nursing Implications: Oral Drugs
Take regularly, same time each day
Take with meals to reduce GI upset
Do not crush, chew or open extended-release forms
Take with 6-8 oz of water
Oral suspensions should be thoroughly mixed
If patient is NPO for a procedure, contact physician regarding AE
Nursing Implications: Intravenous Forms
Follow manufacturer's recommendations for IV delivery - usually given slowly
Monitor vital signs during administration
Avoid extravasation of fluids
Use only normal saline with IV phenytoin
Nursing Implications
Teach patients to keep a journal to monitor:
Response to AED
Seizure occurrence and descriptions
Adverse effects
Instruct patient to wear a medical alert tag or ID
AEDs should not be discontinued abruptly
Instruct patient of the sedating effect of drugs
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