DRG Category: 57

Mean LOS: 5.0 days

Description MEDICAL: Degenerative Nervous System Disorders without Major CC

classification section:



Myasthenia gravis (MG) is an autoimmune disease that produces fatigue and voluntary muscle weakness, both of which become worse with exercise and improve with rest. The muscles that are frequently involved include those for eye and eyelid movement, chewing and swallowing, breathing, and movement of the distal muscles of the extremities. This weakness progressively worsens during the day or at times of stress, so the greatest fatigue is likely to occur at the end of the day. MG frequently accompanies disorders of the immune system or the thyroid gland.

Rapid acute exacerbations result in a 5% mortality rate and are classified as either myasthenic or cholinergic crises. Both crises lead to extreme respiratory distress, difficulty in swallowing and speaking, great anxiety, and generalized weakness, thus making differentiation challenging but crucial for selection of appropriate intensive therapy. Myasthenic crisis is caused by undermedication, whereas a cholinergic crisis results from excessive anticholinesterase medication and is thus likely to occur within 45 to 60 minutes of the last drug dosage. The major complications of MG are respiratory distress or insufficiency, aspiration pneumonia, and poor nutrition linked to eating difficulties.