Deck 30: Myasthenia Gravis

Question 1

Which of the following are among the treatment options for the patient with myasthenia gravis?
1) Pyridostigmine (MestinonÒ)
2) Plasmapheresis
3) Thymectomy
4) Mechanical ventilation

A) 1, 3
B) 2, 4
C) 1, 2, 4
D) 1, 2, 3, 4

Answer 1

1, 2, 3, 4

Question 2

What test is usually performed to confirm the diagnosis of myasthenia gravis?

A) RNS
B) PFT
C) CBC
D) EEG

Answer 2

RNS

Question 3

A 50-kg (110-lb) 30-year-old female patient has myasthenia gravis. Bedside spirometry has found her VC to be 700 mL and NIF -14 cm H?O. Vital signs show a respiratory rate of 38 breaths/min, a heart rate of 140/minute, and blood pressure of 130/90 mm Hg. What should the respiratory therapist recommend?

A) Check the vital signs every hour.
B) Encourage DB&C per protocol.
C) Administer supplemental oxygen per protocol.
D) Initiate mechanical ventilation per protocol.

Answer 3

Initiate mechanical ventilation per protocol.

Question 4

Which of the following disrupt(s) the nerve impulse transmission in myasthenia gravis?

A) MuSK
B) Edrophonium
C) IgG antibodies
D) RNS

Question 5

What is the most sensitive diagnostic test for myasthenia gravis?

A) Ice pack test
B) SFEMG
C) Edrophonium test
D) PEFR

Question 6

The major pathologic or structural changes of the lungs associated with myasthenic crisis include:
1) alveolar consolidation.
2) airway obstruction.
3) mucus accumulation.
4) atelectasis.

A) 1, 4
B) 2, 3
C) 2, 3, 4
D) 1, 2, 3, 4

Question 7

During a myasthenia crisis, a patient was placed on mechanical ventilation but is now stable. What will the chest radiograph most likely show?

A) Normal lungs
B) Mediastinal shift
C) Pericardial tamponade
D) Ground glass appearance

Question 8

What clinical change would be expected following a rest period for a patient with myasthenia gravis?

A) There is no clinical change.
B) Strength decreases.
C) Muscle strength improves.
D) Ascending paralysis descends.

Question 9

Which of the following values would be associated with impending ventilatory failure in a patient with myasthenia gravis?
1) NIF -15cm H₂O
2) VC 10 mL/kg
3) PaCO₂43 mm Hg
4) pH 7.36

A) 1
B) 1, 2
C) 2, 4
D) 1, 2, 3

Question 10

A physician recommended a thymectomy for a patient with generalized myasthenia gravis. The primary benefit of this procedure is to:

A) eliminate the source of AChR antibodies.
B) block the antigen-antibody reactions.
C) remove the source of cholinesterase.
D) cure the ocular myasthenia gravis.

Question 11

A patient with myasthenia gravis will have lung volume and capacity findings that indicate a(n):

A) upper airway obstruction.
B) obstructive pulmonary disorder.
C) restrictive pulmonary disorder.
D) combined obstructive and restrictive disorder.

Question 12

What percentage of patients with only ocular myasthenia gravis are seropositive?

A) <10%
B) 25%
C) 50%
D) 90%

Question 13

Which demographic group(s) is/are most likely to develop myasthenia gravis?
1) African-American females >40 years of age
2) White males <40 years of age
3) Females 15 to 35 years of age
4) Males 40 to 70 years of age

A) 1
B) 4
C) 2, 3
D) 3, 4

Question 14

Which of the following is (are) signs and symptoms associated with myasthenia gravis?
1) Double vision
2) Weakness of neck muscles
3) Drooping of eyelids
4) Difficulty speaking

A) 2
B) 1, 3
C) 2, 3, 4
D) 1, 2, 3, 4

Question 15

Which of the following are associated with myasthenia gravis?
1) It interferes with acetylcholine transmission.
2) It causes weakness of voluntary muscles.
3) It is usually an ascending paralysis starting in the legs.
4) It is usually preceded by a viral infection.

A) 1, 2
B) 3, 4
C) 2, 3, 4
D) 1, 2, 3

Question 16

Complications commonly associated with long-term use of steroids in the management of myasthenia gravis include all of the following EXCEPT:

A) infections.
B) cataracts.
C) pulmonary edema.
D) osteoporosis.

Question 17

If a patient with myasthenia gravis is given edrophonium, what response would be expected?

A) Diaphragmatic strength will increase for 12 to 24 hours.
B) Strength will temporarily improve for 10 minutes.
C) Muscle strength will increase for 48 to 72 hours.
D) Muscle strength will decrease for 10 minutes.

Question 18

A patient has a severe case of generalized myasthenia gravis. It is most important that the patient be monitored for:

A) urine output.
B) atrial fibrillation.
C) hypotension.
D) apnea.

Question 19

In which clinical classification of myasthenia gravis is intubation indicated?

A) Class I
B) Class 1IIb
C) Class V
D) Class II