A patient arrives in the emergency department with rapidly ascending muscle weakness over the past two days, areflexia, and recent history of a gastrointestinal illness. The patient's respiratory effort is adequate, but there is concern for potential progression of symptoms. Which initial management strategy is most appropriate for this patient?
Prescription of antiviral medication
Immediate administration of high-dose corticosteroids
Preparation for potential intubation and respiratory support
Immediate plasmapheresis