Myasthenia gravis (MG) is a long-term neuromuscular disease that leads to varying degrees of skeletal muscle weakness. The most commonly affected muscles are those of the eyes, face, and swallowing. It can result in double vision, drooping eyelids, trouble talking, and trouble walking.

1. PRESENTED BY:
MR. ABHAY RAJPOOT

3. NORMAL NEUROMUSCULAR
JUNCTION: TEXT:
 Axon of motor neuron divides
as they enter skeletal muscles,
& each axonal ending form a
neuromuscular junction. the
transmission of nerve
impulses from the nerve to the
muscles occurs at the
neuromuscular junctions. The
neurotransmitter acetylcholine
is released from the axonal
endings, crosses the synaptic
cleft, attaches to acetylcholine
receptors on the muscle fiber
& stimulate the muscle

4.  It is a chronic autoimmune disorder
characterized by fatigue & severe weakness of
skeletal muscles that worsens with exercise &
improves with rest.
Incidences:
 Women are affected three times more
frequently than men.
 The age for onset for most clients is between
ages 20-30 yrs.

5.  Idiopathic
 80% of people with generalized form of disease
have elevated titers of antibodies to the Ach
receptor in their serum.

6. Due to etiological factors
Destruction & blockage of neuromuscular junction
receptor site by antibodies
Decreased number of acetylcholine receptors &
structural changes
Diminished acetylcholine uptake
Decrease in muscle ability to contract despite of
sufficient amount of acetylcholine

7. Ocular & facial:
 Ptosis (drooping of eyelid)
 Diplopia (double vision)
 Facial weakness
 Dysphagia
 Dysarthria
 Complications- difficulty closing eye, aspiration, impaired
communication
Musculoskeletal:
 Weakness & fatigue
 Decreased function of hand & arms, legs, & neck muscles

9. Respiratory :
 Weakening & of intercostals muscles
 Decrease in diaphragm movement
 Breathless & dyspnea
 Poor gas exchange
Nutritional:
 Inability to chew and swallow
 Decreasing ability to move tongue
 Impairment of fine motor movements-Inability to
feed self
 Complications: Wt loss, Dehydration, malnutrition

10.  Myasthenic crisis- It is a sudden exacerbation
of motor weakness, putting the client at risk of
respiratory failure and aspiration. It is most
often due to under medication , missed doses
of medication or infection.
 Manifestations:
 Tachycardia, Tachypnea, severe respiratory distress,
dysphagia and impaired speech.

11.  Cholinergic crisis:
 It is result of overdose with the
anticholinesterase ( cholinergic) medications
used to treat MG.
 Manifestations: Severe muscle weakness,
vertigo, respiratory distress.
 Treatment: client frequently requires
ventilatory assistants.

12.  History
 Physical Examination
 Anticolinesterase (tensilon or prostigmin) test
 Single fiber electro myeography
Can detect delayed or failed neuro muscular
transmission in muscle fibers supplied by a
single muscle fibre.

14. Medical management:
Medications:
 Anticholinesterase Eg. pyridostigmine
(mestinon)- It act at the neuromuscular
junction and allow acetylcholine to
concentrate at the receptor sites, thus
promoting muscle contraction.
 Glucocorticoids - Eg. Prednisone
 Immunosuppressive agents- Eg.
Cyclosporine or azathioprine (immuran)

15.  Plasmapheresis: It is procedure used to
separate blood cellular components from
plasma. About 50ml per minute is withdrawn
to the centrifuge in the plasmapheresis
machine. The plasma is replaced with donor
plasma or colloids(albumin, normal saline &
electrolytes) and return to the client.
 Goal: To remove the acetylcholine receptor
antibodies thus improving severe muscle
weakness and fatigue.

16.  Thymectomy: Removal of thymus gland may
cause 75% of clients with MG have dysplasia of
the thymus gland.

17.  Ineffective airway clearance related to poor
cough mechanism decreased ribcage expansion
and diminished diaphragm movement.
 Impaired swallowing related to weakness of
laryngeal and pharyngeal muscles involved
with swallowing.
 Imbalanced nutrition less than body
requirement related to less intake of food as
evidenced by dysphagia & muscle weakness.

18.  Schedule periods of rest and avoid stress;
conserve energy when possible.
 Avoid cigarette smoke, alcohol and beverages
with quinine .
 Take medications as prescribed. If
manifestation changes consult the physician;
the dose may need to be adjusted.
 Avoid extremes of temperature; an
environment that is too hot or too cold.
 Avoid people with upper respiratory
infections.

19.  https://www.healthline.com/health/myasthe
nia-gravis
 https://en.wikipedia.org/wiki/Myasthenia_gr
avis
 https://www.mayoclinic.org/diseases-
conditions/myasthenia-gravis/symptoms-
causes/syc-20352036
 https://www.nhs.uk/conditions/myasthenia-
gravis/
 http://www.myasthenia.org/WhatisMG.aspx