Transcript Unit 11: Drugs that affect the CNS

Nancy Pares, RN, MSN
NURS 1950
Metropolitan Community College
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Seizures
◦ Abnormal or uncontrolled neuronal
discharges in the brain
◦ affect
 Consciousness
 Motor activity
 Sensation
◦ Symptom of an underlying disorder-not a
disease itself
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Infectious diseases
Trauma
Metabolic disorders
Vascular diseases
Pediatric disorders
Neoplastic diseases
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High dose of local anesthetics
Drug abuse
Withdrawal from alcohol
Withdrawal from sedative-hypnotics
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Involuntary violent spasm of large
muscles of the face, neck, arms and
legs
Not synonymous with seizure
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Signs and symptoms
◦ Related to the area of the brain with
abnormal activity
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Types-based on International
Classification
◦ Partial (focal)
◦ Generalized
◦ Special epileptic syndromes
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Occur in limited portion of brain
Point of origin: abnormal focus or foci
Clients experience
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Feeling that is vague
Hallucinations with all senses
Extreme emotions
Twitching of arms, legs or face
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Altered levels of consciousness
Involve sensory, motor, autonomic
symptoms
Aura commonly precedes seizure
No memory of seizure
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Travel throughout the entire brain
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Subcatagories
◦ Absence
◦ Atonic
◦ Tonic-clonic
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Common in children
Subtle symptoms
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Staring
Transient loss of consciousness
Eyelid fluttering
Myclonic jerks
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Usually last only a few seconds
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Characterized by stumbling or falling
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Most common
Usually preceded by aura
Tonic phase
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Intense muscle contractions
Hoarse cry at onset
Loss of bowel/bladder control
Shallow breathing
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Clonic phase
◦ Alternating contraction and relaxation of
muscles
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Postictal state (post seizure)
◦ Drowsiness, disorientation, deep sleep
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Febrile seizures
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Myoclonic seizures
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Status epilepticus
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Last one –two minutes
Tonic clonic motor activity
Common in 3-5 year olds
Occur with rapid rise in body
temperature
Affect 5% of all children
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Large jerking body movements
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Quick contraction of major muscles
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Stumbling and falling
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Similar to normal infantile Moro reflex
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Medical emergency
Continuously repeating seizure
Common with generalized tonic-clonic
Continuous muscle contractions
◦ May compromise airway
◦ May cause hypoglycemia, hypothermia,
acidosis
◦ May produce lactic acid
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The choice of drug depends upon
◦ Type of seizure
◦ Client history and diagnostic studies
◦ Pathologic process causing seizures
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GABA= gamma aminobutyric acid
◦ Primary neuro transmitter of brain.
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Drugs that potentiate GABA action
◦ Barbiturates
◦ Benzodiazepines
◦ Misc. agents
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Prototype: phenobarbital (Luminal)
◦ Mechanism of action
 Changing the action of GABA
◦ Primary use
 Controlling seizures
◦ Adverse effects
 Dependence, drowsiness, vitamin deficiencies,
laryngeospasm
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Prototype: diazepam (Valium)
◦ Mechanism of action
 Similar to barbiturates, but safer
◦ Primary use
 Short term seizure control
◦ Adverse effects
 Drowsiness and dizziness
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Prototype: valproic acid (Depakene)
Mechanism of action:
◦ similar to benzo’s and barbiturates
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Primary use
◦ Adjunct therapy
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Adverse effects:
◦ Sedation, drowsiness, GI upset, prolonged
bleeding time
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Prototype: phenytoin (Dilantin)
Mechanism of action:
◦ Desensitize sodium channel blockers
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Primary use
◦ Treatment of all types of seizures, except absence
seizures
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Adverse effects:
◦ CNS depression, gingival hyperplasia, skin rash,
cardiact dysrhythmias, and hypotension
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Prototype drug: valproic acid (Depakene)
Mechanism of action:
◦ Desensitize sodium channels
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Primary use:
◦ Absence seizures
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Adverse effects:
◦ Limited CNS depression, visual disturbances, ataxia,
vertigo, HA, GI, hepatotoxicity, pancreatitis
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Prototype: ethosuximide (Zarontin)
Mechanism of action
◦ Suppress calcium influx
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Primary use
◦ Absence seizures
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Adverse effects:
◦ Rare, but include drowsiness, dizziness, lethargy
◦ Rare, but serious: lupus, leukopenia, aplastic
anemia, Stevens-Johnson syndrome
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Barbiturates:
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Monitor for liver and kidney function
Category D in pregnancy
Depletion of nutrients
Alcohol and ginko biloba interactions
Client teaching
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Use reliable contraception
Immediately report pregnancy
Report excessive bleeding,drowsiness, bone pain
Avoid alcohol and gingko biloba
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Monitor for drug abuse potential
Pregnancy risk (category D)
Contraindicated in narrow angle glaucoma
Liver and kidney function monitored
Respiratory depression
In event of overdose
◦ Give flumazenil (Romazicon)
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Give IV valium and ativan
Do not mix with other drugs in IV line
Client teaching
◦ Avoid ETOH, OTC drugs, herbal preps,
nicotine, driving and hazardous activities
◦ Rebound seizures if d/c abruptly
◦ Take with food
◦ These drugs most often used illegally
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Monitor serum drug levels, liver and kidney
function
Monitor for bleeding disorders
Fatal hepatotoxicity can occur
Contraindicated
◦ Hx of heart block or seizures due to low BS
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Client teaching
◦ Routine labs; report s/s of toxicity, bleeding,
pregnancy, hypoglycemia
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Monitor for liver and kidney function
Pregnancy category C
Adverse reactions:
◦ Drowsiness, HA, euphoria, n/v, weight loss, abd.
Pain
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Life threatening reactions:
◦ Mental depression with suicide intent
◦ Blood dyscrasias and Stevens-Johnson syndrome
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Symptoms of overdose
◦ CNS depression, stupor, ataxia, coma
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Client teaching
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Report mood changes or suicidal thoughts
Avoid driving and hazardous activities
Take with food
Do not stop abruptly
Report weight loss and anorexia
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Start with smallest dose of med
Add additional drugs, if needed
Monitor serum drug levels
Withdrawal of meds
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Seizure free for three years
Done gradually
Resume meds if seizures return
Knowledge of rebound seizures
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Disturbed sensory perception RT
seizure activity
Risk for injury RT seizure activity
Deficient knowledge RT disease/drugs
Noncompliance RT drug regime
Noncompliance RT serum lab testing
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Absence/reduction in number of
seizures
No injury during seizure
Understanding of disease
Understanding of drug regimen
Compliance with lab testing
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Sedative:
◦ An agent that calms nervousness, irritability
and excitement
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Hypnotic
◦ An agent that induces sleep
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Results from damage to the motor area
of the cerebral cortex
Conditions:
◦ Cerebral palsy
◦ severe head injury, spinal cord injury or
lesions
◦ stroke
◦ dystonia
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Goals of muscle relaxants
◦ Minimize discomfort
◦ Increase ROM
◦ Improve ability to function independently
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Centrally acting muscle relaxants
◦ Prototype: cyclobenzaprine (Flexeril)
◦ Mechanism of action
 Inhibits upper motor neuron activity
 Alters simple spinal reflexes, causes CNS depression
◦ Primary Use
 Treat localized spasms
◦ Adverse effects
 CNS depression, hepatic toxicity, physical dependence,
anticholinergic effects
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Direct acting antispasmodics
◦ Prototype: dantrolene (Danantrium)
◦ Mechanism of action
 Interferes with release of calcium ions in skeletal
muscle
◦ Primary use
 Relieve dystonias and leg cramps
◦ Adverse effects
 Hepatic toxicity, muscle weakness, drowsiness,
diarrhea
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Assessment
◦ Monitor pain, LOC, vital signs
◦ Monitor muscle tone, ROM, degree of spasms
◦ Monitor labs
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Nursing Dx
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Pain
Impaired physical mobility
Risk for injury
Deficient knowledge
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Goals
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Decrease pain
Increase range of motion (ROM)
Reduce muscle spasms
No adverse effects of drugs
Knowledge of drug regimen