A. Decription
1. Myasthenia gravis is a neuromuscular disease characterized by considerable weakness and abnormal fatigue of the voluntary muscles.
2.A defect in the transmission of nerve impulses at the myoneural junction occurs.
3.Causes include insufficient secretion of acetylcholine,excessive secretion of cholinesterase,and unresponsiveness of the muscle fiber to acetylcholine.
B.Assessment
1.weakness and fatigue
2.difficulty chewing
3.dysphagia
4. ptosis
5.diplopia
6.weak,hoarse voice
7.difficulty breathing
8.diminished breath sounds
9.respiratory paralysis and failure
C.INTERVENTIONS
1.monitor respiratory status and ability to cough and deep breathe adequately.
2.monitor for respiratory failure.
3.maintain suctioning and emergency equipment at the bedside.
4.monitor vital signs.
5.monitor speech and swallowing abilities to prevent aspiration.
6.encourage the client to sit up when eating.
7.assess muscle status.
8.instruct the client to conserve strength.
9.plan short activities that coincide with times of maximal muscle stength.
10.monitor for myasthenic and cholinergic crises.
11.administer anticholinesterase medications as prescribed.
12.instruct the client to avoid stress, infection, fatigue ,and over-the counter medications.
13.instruct the client to wear a medic-alert bracelet.
14.inform the client about services from the myasthenia gravis foundation.
D.Anticholinesterase medications
1.Action:increase levels of acetycholine at the myoneural junction
2.medications
a.neostigmine bromide(prostigmine)
b.pyridostigmine bromide(mestinon,regonol)
c.edrophonium chloride(tensilon)
3.side effects
sweating,salivation,nausea,diarrhea and abdominal cramps,bradycardia,hypotention
4.interventions
a.administer medications on time.b.administer medication 30 minutes before meals with milk and crackers to reduce gastrointestinal upset.c.monitor and record muscle strength.d.note that excessive doses lead to cholinergic crisis.e.have the antidote (atropine sulfate)available.
E.Myasthenic crisis
1. description
a.myasthenic crisis is an acute exacerbation of the disease .
b.the crisis is caused by a rapid ,unrecognized progression of the disease,an inadequate amount of medication,infection,fatigue,or stress.
2.Assessment
a.increased pulse ,respirations,and blood pressure
b.anorexia and cyanosis
c.bowel and bladder incontinence
d.decreased urine output
e.absent cough and swallow reflex
3.interventions
a.assess for signs of myasthenic crisis.
b.increase anticholinesterase medication.
F.Cholinergic crisis
1.description
a.cholinergic crisis results in depolarization of the motor plates.
b.the crisis is caused by overmedication with anticholinesterase.
2.assessment
a.abdominal cramps
b.nausea,vomiting,and diarrhea
c.blurred vision
d.pallor
e.facial muscle twitching
f.hypotension
g.pupillary miosis
3.interventions
a.hold anticholinesterase medication.
b.prepare to administer the antidote,atropine sulfate,if prescribed.
G.Tensilon test
1.description:the tensilon test is performed to diagnose myasthenia gravis and to differentiate between myasthenic crisis and cholinergic crisis.
2.to diagnose myasthenia gravis
a.tensilon injection is administered to the client.
b.positive for myasthenia gravis :client shows improvement in muscle strength after the administration of tensilon.
c.negative for myasthenia gravis :client shows no improvement in muscle strength,and strength may even deteriorate after injection of tensilon.
3.to differentiate crisis
a.myasthenic crisis:tensilon is administered,and if strength improves,the client needs more medication.
b.cholinergic crisis:tensilon is administered, and if weakness is more severe,the client is overmedicated;administer atropine sulfate,the antidote, as prescribed.
above information from saunders comprehensive review for NCLEX-RN Examination
留言列表
