skip to main content

Myasthenic crisis — RCPSC EM MCQ

Instant feedback + full explanation. One question, done properly.

HardNeurological emergenciesMyasthenic crisisRCPSC EM

A 34-year-old with myasthenia gravis presents with diplopia, dysphagia and dyspnoea after a respiratory infection. Forced vital capacity is 12 mL/kg and negative inspiratory force is -18 cmH2O. Oxygen saturation is 95% but she has weak cough. What is the most appropriate next step?

Educational content. Not a substitute for clinical judgement or local policy.

Reveal the answer and explanation

Correct answer: D — Prepare for controlled intubation and consult neurology/ICU for myasthenic crisis treatment

Myasthenic crisis can present with normal oxygen saturation until late. Low vital capacity, weak cough and bulbar symptoms indicate impending ventilatory failure and need controlled airway planning plus disease-specific therapy.

Reference: Canadian neurological emergency practice; ACLS airway management