Malignant hyperthermia and motor disorders

Question 1

Is an autosomal-dominant disease that usually presents in the second or third decade and is the most common inherited myopathy in adults.

Answer 1

Myotonic dystrophy

Question 2

What are the important muscle relaxant considerations in patients with myotonic dystrophy?

Answer 2

Exaggeration of muscle contraction

Nondepolarizing relaxants will not ablate myotonic contractures

Question 3

Is an autoimmune disease of the NEUROMUSCULAR junction.

Answer 3

Myasthenia gravis

Question 4

What is the first presentation of myasthenia gravis?

Answer 4

Very commonly extraocular muscles are the first

affected, and the patient complains of diplopia or ptosis.

Question 5

Describe the altered responsiveness of myasthenic patients to muscle relaxants.

Answer 5

Increase dose of succinylcholine to 2 mg/kg
1/10th dose of non-dep
Often at anesthetic induction no muscle relaxant is necessary to achieve endotracheal intubation.

Question 6

This is an immune-mediated disease of the neuromuscular junction that frequently arises in the
setting of malignancy, often small-cell carcinoma of the lung

Answer 6

Lambert-Eaton myasthenic syndrome
Antibodies affect the PRESYNAPTIC junction and
result in decreased acetylcholine release.
Proximal muscles are affected more than distal, and legs more than arms.
Sensitive to ALL mm relaxants