Myastenia Gravis

• Myasthenia Gravis 


  A neuromuscular disorder characterized by failure of transmission of nerve impulses at the myoneural junction.
• MG may be caused by decreased number of functioning acetylcholine receptor sites. It is also associated with autoimmune disorders.
• MG: Manifestations

  • Muscle weakness associated with activity relieved by rest
  • Ptosis
  • Diplopia
  • Dysphagia
• The diagnostic test for MG is Tensilon Test (Edrophonium) Test. Tensilon is a short-acting cholinergic. (It increases acetycholine)
• MG: Diagnostic Test

  • Tensilon is administered IV (2 mg. first, then 8 mg.). Positive Tensilon Test is observed as improvement in muscular strength. Muscle weakness returns in 3 to 5 minutes.
  • The antidote for cholinergic is Atropine sulfate (anticholinergic).
• MG: Management

  1. Assess swallowing and gag reflex before feeding the client. To prevent aspiration.
  2. Administer medications 20 - 30 minutes before meals. To improve ability to swallow and prevent choking.
  3. Administer medications at an exact time. To prevent myasthenic crisis that results to respiratory distress.
  4. Start meal with cold beverage. To contract muscles of the throat and improve ability to swallow.
  5. Plasmapheresis. This involves separation of antibodies from the plasma to inhibit autoimmune response.
• Myasthenia Gravis: Pharmacothreapy

  Acetylcholinesterase Inhibitors / Cholinesterase Inhibitors

  ex: Neostigmine, Pyridostigmine
• MG: Pharmacotherapy

  Acetylcholinesterase

  • These medications transmit neuromuscular impulses by preventing the destruction of acetylcholine. Therefore, there is increased muscle strength.
• The 2 major complications of MG are myasthenic crisis and cholinergiccrisis.
• Myasthenic crisis is caused by undermedication.


  The clinical manifestations of myasthenic crisis are as follows: sympathetic

  • Interventions for myasthenic crisis are as follows: increase cholinergic
• Cholinergic crisis is caused by excessive medications.


  The clinical manifestations of cholinergic crisis are as follows: Parasympathetic

  Interventions for cholinergic crisis are as follows:

  • Discontinue all cholinergic drugs until cholinergic effects decrease.
  • atropine may be necessary to counteract severe
• Survival Guide for clients with MG:

  • Reschedule daily task. To prevent weakness.
  • Secure "handicapped" parking sticker.
  • Frequent rest periods.
  • Have alarm clock available - to take medications on time. This prevents myasthenie crisis.
  • Patch each eye alternately for diplopia (double vision).
  • Start meal with cold beverage. To contract muscles of the throat and prevent aspiration.