Multiple Sclerosis
Background
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Heterogenous disorder with variable clinical & pathologic features
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Inflammation, demyelination & denervation are the major pathologic mechanisms that cause the clinical manifestations
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Cause unknown, most widely accepted theory is of an inflammatory immune-mediated disorder
Considerations
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Multisystem effects of demyelination:
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Aspiration risk (bulbar dysfunction)
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Respiratory failure/insufficiency (central hypoventilation & neuromuscular weakness)
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Autonomic dysfunction with possible hemodynamic instability
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Altered response to NMBs (neuromuscular blocking drugs):
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Succinylcholine contraindicated due to hyperkalemia risk (denervation, misuse myopathy)
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Sensitive to NdMRs (nondepolarizing muscle relaxants), but can also be resistant
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Potential perioperative exacerbation of disease:
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Neuraxial technique (spinal > epidural) but very controversial & some sources suggest regional/neuraxial acceptable
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Hyperthermia
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Immunosuppressive medications (steroids, interferon, methotrexate)
Goals
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Minimize aspiration risk (consider prophylaxis, RSI)
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Maximize respiratory function (avoid paralysis, full NMB reversal, secretions, pain management)
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Maintain hemodynamic stability
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Prevent postoperative exacerbations by avoiding triggers (hyperthermia, stress, +/- neuraxial)
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Inform patient of potential perioperative aggravation of symptoms
Conflicts
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Neuraxial technique vs. disease exacerbation:
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Spinal traditionally considered contraindicated, but controversial
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Low dose epidural most likely safe, have discussion with patient
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Peripheral nerve block is safe, as those nerves are not involved
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RSI vs. hemodynamic stability
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RSI vs. avoid succinylcholine
Pregnancy Considerations
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Neuraxial (both epidural/spinal) NOT contraindicated
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Discuss risk with patient that there may be post-operative/post-delivery relapse, regardless of anesthetic technique