Question

A 56-year-old patient has been diagnosed with myasthenia gravis. Discuss the differences in nursing management between myasthenic crisis and cholinergic crisis.

Answer 1

Myasthenia crisis

Causes-Exacerbration of myasthenia following precipitating factors or failure to take drug as prescribed or drug dose too low.

Cholinergic crisis

Cause-Overdose of anticholinesterase drugs resulting in increased ACh at the receptor sites, remission.

Differential diagnosis

Myasthenia Gravis

• Improved strength after IV administration of anticholinesterase drugs;Increased weakness of skeletal muscles manifesting as ptosis, bulbar signs or dyspnea. Cholinergic Crisis
• Weakness within 1 hr after ingestion of anticholinesterase;increased weakness of skeletal muscles manifesting as ptosis ,bulbar signs, dyspnea, effects on smooth muscle include pupillary miosis, salivation ,diarrhea, nausea or vomiting, abdominal cramps, increased bronchial secretions, sweating or lacrimation.

Management

Myasthenia crisis

• Provide ventillatory support.
• Frequent suction to ensure adequate airway to prevent aspiration.
• Tubefeeding.
• Insertion of foleys catheter.
• Plasmapheresis as per physicians hospital protocol.
• A Tensilon test is conducted to differentiate between the two conditions.

Cholinergic crisis.

• Respiratory support.
• Withhold Neostygmin used for 1-3days.
• Usually improve with remission.
• Revaluate medicine once it clears.