Myasthenia Gravis

MYASTHENIA GRAVIS (MG)

- disturbance in transmission of impulses from nerve to muscle cell at neuro muscular

junction.

Common in Women, 20 – 40 yo, unknown cause or idiopathic

Autoimmune – release of cholenesterase – enzyme

Cholinesterase destroys ACH (acetylcholine) = Decrease acetylcholine

Descending muscle weakness

(Ascending muscle weakness – Guillain Barre Syndrome)

Nursing Priority:

1) a/w

2) aspiration

3) immobility

Sign and Symptoms

1.) Ptosis – drooping of upper lid ( initial sign)

Check Palpebral fissure – opening of upper & lower lids = to know if (+) of MG.

2.) Diplopia – double vision

3.) Mask like facial expression

4.) Dysphagia – risk for aspiration!

5.) Weakening of laryngeal muscles – hoarseness of voice

6.) Resp muscle weakness – lead respiratory arrest. Prepare at bedside tracheostomy set

7.) Extreme muscle weakness during activity especially in the morning.

Diagnostic Test

1. Tensilon test (Edrophonium Hcl) – temporarily strengthens muscles for 5 – 10 mins. Short term- cholinergic. PNS effect.

Nursing Management

1. Maintain patent a/w & adequate vent by:

a.) Assist in mechanical vent – attach to ventilator

b.) Monitor pulmonary function test. Decrease vital lung capacity.

2. Monitor VS, I&O neuro check, muscle strength or motor grading scale (4/5, 5/5, etc)

3. Siderails

4. Prevent complications of immobility. Adult-every 2 hrs. Elderly- every 1 hr.

5. NGT feeding

Administer meds –

a.) Cholinergics or anticholinesterase agents

Mestinon (Pyridostigmine)

Neostignine (prostigmin) – Long term

- Increase acetylcholine

s/e – PNS

b.) Corticosteroids – to suppress immune resp

Decadron (dexamethasone)

Monitor for 2 types of Crisis:

7. Assist in surgical proc – thymectomy. Removal of thymus gland. Thymus secretes auto immune antibody.

8. Assist in plasmaparesis – filter blood

9. Prevent complication – respiratory arrest

Prepare tracheostomy set at bedside.