Multiple Sclerosis (MS)

Anesthesia Implications

Anesthesia Implications

Keep the patient normothermic – HYPERthermia (as little as 1 degree Celcius) can cause exacerbation/onset of MS symptoms

Avoid stressors – Increased stress in these patients can also exacerbate MS symptoms

Labile – Autonomic dysfunction implies that the patient will have increased risk for exaggerated hemodynamic changes during induction as well as sensitivity to vasodilators and sympathomimetics.

Thorough preoperative interview – find preoperative neuropathies and triggers that exacerbate/worsen MS symptoms.  Document thoroughly to rule out any postoperative findings.

Succinylcholine – generally contraindicated in MS patients as these patients are prone to succinylcholine-induced hyperkalemia.

Paralytic sensitivity – Nerve dysfunction combined with commonly-used muscle relaxants can cause a delayed postoperative muscular function.  Use neuromuscular blockade judiciously.

Spinal anesthesia – In some studies, spinal anesthesia has been linked to postoperative exacerbation of MS symptoms.

Epidural anesthesia and peripheral blockade – have NOT been linked to postoperative exacerbation of MS symptoms.  However, some studies suggest that these patients may require lower doses of local anesthetics for epidurals.

Local anesthetic cautions – The pathophysiology of this disease theoretically poses concerns for greater risks of local anesthetic toxicity.

Post-partum patients – 20-30% of post-partum patients, regardless of the anesthetic approach, will experience worsening MS symptoms.  The reasons are unclear.

Corticosteroids – If the patient is on corticosteroids, treatment should continue throughout the perioperative period

Pathophysiology

Autoimmune disease (T-cell mediated autoantibodies against neuron myelin) which results in neuronal inflammation, demylenation, and axonal damage. Plaques develop in the central nervous system.

These often result in the patient having baseline diplopia, muscle weakness, neuropathies/paralysis, along with organ dysfunction.

MS results in up-regulation of acetylcholine receptors

Muscle weakness is greater in the lower limbs than the upper extremities. More severe cases involve weakness of respiratory muscles.

Affects primarily women between 20 and 40 years of age.

Unknown etiology.

Symptoms typically characterized by exacerbations and remissions. In rare cases the symptoms are continuous.

Primary treatments are aimed at reducing inflammation using corticosteroids (glucocorticoids), which as stated above, should continue through the perioperative period.

Other treatments:
-baclofen and benzodiazepines for spasticity
-propranolol or anticonvulsants (gabapentin) for tremors
-oxybutynin and propantheline for bladder spasticity
-SSRI’s for mood disorders

Diagnosis is made on clinical symptoms, CSF antibody analysis (increased immunoglobulin G), and MRI (to detect CNS plaques).

References

Miller. Miller’s Anesthesia. 2015. p. 1266, 1271-1272, 1300