UMEM Educational Pearls

Title: Myasthenia Graves - Airway Management/Disposition

Category: Neurology

Keywords: MG, myasthenia graves, intubation, fvc, forced vital capacity (PubMed Search)

Posted: 4/22/2009 by Aisha Liferidge, MD (Updated: 11/27/2024)
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  • Patients with severe or rapidly progressive weakness due to a Myasthenia Graves (MG) exacerbation should be admitted to an intensive care unit.
     
  • Acute MG patients' forced vital capacity (FVC) should be monitored every 2 to 4 hours to accurately assess the function of their respiratory muscles.
     
  • FVC can easily be measured at the bedside, particularly by a respiratory technician.
     
  • Once the patients' FVC is consistently approaching or reaches 15 mL/kg, the patient should be electively intubated in order to ensure protection of their airway.  In an average sized adult, an FVC of 1000 mL is the point at which respiratory failure is eminent.
     
  • Arterial blood gas abnormalities are not reliable indicators of respiratory muscle decompensation, and typically occur as a late sign of respiratory failure.
     
  • Once the patient is intubated, anticholinesterase medications are typically withdrawn.