• Myaesthenia gravis
• IgG autoantibodies against ACh receptors
• Possible initiated by the thymus gland with B & T lymphocytes becoming sensitised to ACh.
• Clinical features
• Females commoner (20-30y)
• Males present later (60-70y)
• Fatiguability characteristic
• Can cause occular, bulbar, facial, generalised and limb muscle weakness
• Associated with other autoimmune conditions
• Diagnosis
• History
• EMG
• Progressive decrease in compound muscle action potentials
• Anti-ACh antibodies
• 10 mg of edrophonium given (Tensilon test)
• Anaesthetic management
• Assess bulbar function
• PFTs
• Chest physio pre-op
• May need prolonged ventilation if:
• Long disease duration
• FVC <2.9L
• Generalised disease
• Chronic respiratory disease
• TFTs
• Some have thyroid dysfunction
• Assess airway as may have thymoma
• Relative resistance to sux
• Very sensitive to NDMRs
• Predictors of respiratory failure
• Disease duration > 6 yrs
  Daily pyridostigmine dose > 750mg
  Coexisting lung disease
  Pre-op VC of < 2.9L
  Major body cavity surgery
  Bulbar involvement
• Treatments
• Plasma exchange
• Short term remission
• IV Ig
• Anticholinesterase therapy
• Immunosupression
• Prednisolone
• Azothiaprine
• Cyclosporine
• Thymectomy
• Avoid precipitants
• Aminoglycosides, quinine, β-blockers
• CEACCP
  Link:ceaccp.oxfordjournals.org/content/2/3/88.full.pdf