GUILLAIN BARRÉ SYNDROME
Guillain–Barré syndrome (GBS), a relatively com-mon disorder affecting one to four individuals per 100,000 population, is characterized by a sudden onset of ascending motor paralysis, areflexia, and variable paresthesias. Subtypes of GBS include acute inflammatory demyelinating polyneuropathy (about 75% of cases), acute motor axonal neuropathy (with antibodies against gangliosides), and acute motor sensory axonal neuropathy. Bulbar involvement, including respiratory muscle paralysis, is a frequent complication. Pathologically, the disease seems to be an immunologic reaction against the myelin sheath of peripheral nerves, particularly lower motor neu-rons. In most instances, the syndrome seems to fol-low viral respiratory or gastrointestinal infections; the disorder can also present as a paraneoplastic syndrome associated with Hodgkin’s disease or as a complication of human immunodeficiency virus infection. Some patients respond to plasmapheresis. The prognosis is relatively good, with most patients recovering completely; unfortunately, however, approximately 10% of patients die of complications, and another 10% are left with long-term neurologic sequelae.
Anesthetic management is complicated by lability of the autonomic nervous system in addi-tion to concerns about respiratory insufficiency. Exaggerated hypotensive and hypertensive responses during anesthesia may be seen. As with other lower motor neuron disorders, succinylcholine should not be used because of the risk of hyperkalemia. The use of regional anesthesia in these patients remains con-troversial, as it might worsen symptoms. As with all decisions, the risks and benefits of regional versus general anesthesia must be weighed on an individual basis. As damaged nerves are more susceptible to a second injury (the “double crush” effect), perfor-mance of neuraxial techniques in patients with pre-existent neurologic dysfunction should be carefully considered.