Chapter 14 - Antiepileptic Drugs Flashcards
What is epilepsy caused by?
excessive electrical activity of neurons in cerebral cortex
What is a seizure?
brief episode of abnormal electrical activity in nerve cells of brain -> may/may not lead to convulsion
What is a convulsion?
more severe seizure involuntary spasmodic contractions of any/all voluntary muscles in body, including skeletal, facial, and ocular
What is epilepsy?
chronic, recurrent pattern of seizures
Primary Epilepsy Another name and what cause
Idiopathic Epilepsy Cause cannot be determined more than 50% of cases
Secondary Epilepsy Another name and what cause
Symptomatic Epilepsy Distinct cause identified: trauma, infection, cerebrovascular disorder Infants/children: r/t developmental defects, metabolic disease/injury at birth Adults: acquired brain disorder is major cause
What are grand mal seizures now known as?
Generalized onset seizures
What is happening in generalized-onset seizures?
neuronal activity originating simultaneously in both hemispheres
What are the subtypes of generalized onset seizures?
- Tonic-clonic
- tonic
- clonic
- atonic (drop attacks)
- myoclonic
- absence and infantile spasms
Who is generalized onset seizures most often seen in?
children
How will a generalized onset seizure present itself to you?
- loss of consciousness
- no postical confusion
- may have rhythmic movements
- no convulsion
What are the 3 types of partial-onset seizures?
- Simple (used to be “petit mal seizures”)
- Complex
- secondary generalized tonic-clonic seizure
Characteristics of Simple Partial-onset seizures
brief loss of awareness (blank stare), no LOC
hallucinations
autonomic nervous system responses
personality changes
motor symptoms are commonly at face, arms, and leg
What are the classifications of seizures?
- Partial seizures
- simple
- complex - Generalized seizures
- Unclassified seizures
Characteristics of Complex Partial-onset Seizures
impaired consciousness
memory impairment
behavioral effect
aura, chewing, swallowing, unreal feelings
tonic, clonic, or tonic-clonic seizures
Characteristics of Secondary Generalized Tonic-Clonic Seizure
Partial onset seizures that progress
Occurs in up to 40% of pts
Postictal confusion
What is an Unclassified Seizure?
Seizures that do not fit into any other category
What can status epilepticus lead to?
hypotension, hypoxia, and cardiac dysrhythmias
which can all lead to brain damage and death
What is status epilepticus?
multiple seizures occurring without recovery between
What can febrile seizures progress to?
Status epilepticus
What drugs are used to treat status epilepticus?
- diazepam
- fosphenytoin
- lorazepam (off label use)
- phenobarbital
- phenytoin
Page 221, Table 14-3 has all the doses, onsets, etc.
What are Antiepileptic Drugs (AEDs) also known as?
anticonvulsants
What are the goals of therapy using AEDs?
control/prevent seizures while maintaining reasonable quality of life
minimize adverse effects/drug-induced toxicity
How long does AED therapy last? When can the pt discontinue?
therapy is usually lifelong
Pts who are seizure-free for 1-2 years may be able to discontinue
_______ drug therapy started before _______ drug therapy
single drug therapy started before multiple drug therapy
Titrate antiepileptic drugs to the lowest effective level. True or false?
True
MOA of AEDs
Exact MOA is unknown.
AEDs are thought to alter movement of Na, K, and Ca ions across nerve cells in the brain
- Increase the threshold of activity (reduce nerve’s ability to be stimulated)
- Limit the spread: suppress transmission of impulses from one nerve to the next
- Decrease the speed of nerve conduction within a neuron
Overall effect of MOA and AEDs
Neurons stabilized
Neuron hyperexcitability decreased
Excessive nerve impulse spread decreased
Indications of AEDs
prevention/control of seizure activity
long-term maintenance therapy for chronic, recurring seizures
acute treatment of convulsions and status epilepticus
other uses
Adverse effects of AEDs
Numerous - vary per drug
often necessitate change in meds
Phenytoin: long-term may cause gingival hyperplasia, acne, hirsutism, and dilantin facies
black box warning (2008): suicidal thoughts/behavior is twice the risk
5 AEDs
PGVTP
- Barbiturates, such as phenobarbital (Luminal)
- gabapentin (Neurontin)
- valproid acid (Depakene)
- topiramate (Topamax)
- Hydantoins, such as phenytoin (Dilantin) and fosphenytoin
People Grab Vaginas To Please
Slide 15-16, I only wrote the yellow ones
Nursing Implications: Assessment
Health history, including current meds
Drug allergies
Renal and Liver function studies CBC
baseline levels
basline V/S
EEG, MRI, CT scans
baseline neurologic exam
6 rules for taking an oral AED
RM(DN)W(OM)
- take same time everyday
- take with meals (decrease GI upset)
- do not crush, chew, or open extended-release forms
- take with 6-8 oz of water
- oral suspensions should be mixed
- if pt is NPO, contact physician
Real Men Do Not Water On Men
Regular Meals Do Not (crush, chew, open) Water Oral Mixed
4 rules for IV form AEDs
- follow manufacturer’s recommendations for IV delivery, usually given slowly
- monitor V/S
- avoid extravasation of fluids
- use only normal saline with IV phenytoin
What to teach pt’s regarding AEDs?
- keep a journal to monitor response to AED, seizure occurrence/descriptions, adverse effects
- wear med alert tag/ID
- AEDs should not be discontinued abruptly
- instruct pt of sedating effect
- driving may be prohibited
- teach pts therapy is long term/possibly lifelong (not a cure)
Nursing Implications: What to monitor for
- therapeutic effects
- decreased/absent seizure activity - adverse effects
- mental status, mood, LOC, sensorium changes
- eye problems, visual disorders
- sore throat, fever (hydantoins may cause blood dyscrasias
