Plasmapheresis as an Alternative When IVIG is Contraindicated in Myasthenic Crisis
Plasmapheresis is an effective and appropriate alternative treatment for myasthenic crisis when IVIG is contraindicated, and in life-threatening presentations, plasmapheresis may actually be the preferred first-line option. 1
Treatment Options in Myasthenic Crisis
When IVIG Cannot Be Used
- Plasmapheresis serves as the primary alternative immunomodulatory therapy when IVIG is contraindicated or unavailable for myasthenic crisis 1
- Both therapies are considered equally effective first-line treatments for myasthenic crisis with respiratory failure, making either an acceptable choice 2
- The ESMO guidelines specifically note that for life-threatening symptoms with respiratory and bulbar involvement, plasma exchange might be the favorable option 1
Contraindications to Consider for Plasmapheresis
Before initiating plasmapheresis, verify the patient does not have 1:
- Renal failure
- Hypercoagulable states
- Active sepsis
- Hemodynamic instability
Clinical Efficacy Evidence
- Plasmapheresis demonstrates faster initial response compared to IVIG, with significantly reduced ICU stay length and earlier improvement in quantitative myasthenia gravis scores at one week off ventilation 3
- However, clinical outcomes are equivalent between both treatments at one month post-treatment 3
- Case series demonstrate that plasmapheresis can successfully rescue patients who fail to respond to initial IVIG therapy 4
Treatment Protocol
Standard Plasmapheresis Regimen
- Administer 4-5 sessions of plasmapheresis over 5 days (one calculated plasma volume per session) 1, 5
- Daily scheduling appears more effective than alternate-day scheduling 5
- Double filtration plasmapheresis (DF) and immunoadsorption (IA) are both effective methods 5
Concurrent Therapies
Combine plasmapheresis with 1:
- Methylprednisolone 1-2 mg/kg daily (lower doses preferred initially in myasthenia gravis to avoid steroid-induced exacerbation)
- Pyridostigmine 30-600 mg daily orally (may be discontinued if patient requires intubation)
- Corticosteroid taper based on symptom improvement
Critical Timing Consideration
Never administer plasmapheresis immediately after IVIG, as plasmapheresis will remove the immunoglobulin that was just administered, making the sequence counterproductive 1, 6
Monitoring for Complications
Watch for plasmapheresis-associated adverse events 7:
- Hypotension and shock (most common complication)
- Thromboembolism
- Opportunistic infections
- Hypocalcemia from citrate anticoagulation
Expected Clinical Course
- Mean duration of intubation ranges from 10-12 days with either therapy 2
- Hospital length of stay averages 25-30 days 2
- Effects typically last only 2-3 weeks, necessitating additional long-term immunosuppressive therapy to prevent relapse 7
- All patients should receive concurrent immunosuppressive agents (corticosteroids, azathioprine, or mycophenolate mofetil) to maintain remission 7
Prognostic Factors
Better response to plasmapheresis correlates with 5:
- Higher baseline myasthenia gravis severity scores
- Non-thymoma patients
- Younger age at disease onset
- Higher immunoglobulin G removal rates