Guillain-Barré syndrome is an acute polyneuropathy characterized by immune-mediated peripheral nerve myelin sheath or axon destruction.

The prevailing theory is that antibodies directed against myelin sheath and axons of peripheral nerves are formed in response to a preceding viral or bacterial illness. Symptoms are at their worst in 2 to 4 weeks, and recovery can vary from weeks to a year.



Classically, Guillain-Barré syndrome is preceded by a viral illness, followed by ascending symmetric weakness or paralysis and areflexia or hyporeflexia. Paralysis may ascend to the diaphragm, compromising respiratory function and requiring mechanical ventilation in one third of patients. Autonomic dysfunction may be present as well.

There are several variants of Guillain-Barré syndrome. The Miller-Fisher syndrome variant is associated with Clostridium jejuni infection. It is preceded by diarrhea and is characterized by ophthalmoplegia, ataxia, and decreased or absent reflexes. Weakness is less severe and the disease course is milder than Guillain-Barré syndrome. Antibody testing for C. jejuni can confirm the diagnosis. Acute motor axonal neuropathy is a pure motor variant, also associated with C. jejuni infection, and is seen in Japan and China. Another variant is acute motor and sensory axonal neuropathy, with loss of both motor and sensory function. This variant begins abruptly, progresses rapidly, and has a prolonged course and poor prognosis.


The diagnosis is mostly historical, but lumbar puncture and electrodiagnostic information can improve confidence in the diagnosis. 

Diagnostic Criteria for Classic Guillain-Barré Syndrome


  • Progressive weakness of more than one limb

  • Areflexia


  • Progression over days to weeks

  • Recovery beginning 2–4 weeks after cessation of progression

  • Relative symmetry of symptoms

  • Mild sensory signs and symptoms

  • Cranial nerve involvement (Bell's palsy, dysphagia, dysarthria, ophthalmoplegia)

  • Autonomic dysfunction (tachycardia, bradycardia, dysrhythmias, wide variations in blood pressure, postural hypotension, urinary retention, constipation, facial flushing, anhydrosis, hypersalivation)

  • Absence of fever at onset

  • Cytoalbuminologic dissociation of cerebrospinal fluid (high protein and low white cell count)

  • Typical findings on electromyogram and nerve conduction studies

    CSF analysis shows high protein levels (>45 milligrams/dL) and WBC counts typically <10 cells/mm3, with predominantly mononuclear cells. When there are >100 cells/mm3, other considerations include HIV, Lyme disease, syphilis, sarcoidosis, tuberculous or bacterial meningitis, leukemic infiltration, or CNS vasculitis. Electrodiagnostic testing demonstrates demyelination. Nerve biopsy reveals a mononuclear inflammatory infiltrate. If MRI is performed to rule out alternative diagnoses, it will show enhancement of affected nerves.



The first step in management is assessment of respiratory function. Airway protection in advance of respiratory compromise decreases the incidence of aspiration and other complications. A well-established monitoring parameter is vital capacity, with normal values ranging from 60 to 70 mL/kg. A simple bedside assessment of respiratory status is obtained by trending values reached when the patient counts from 1 to 25 with a single breath. Avoid depolarizing neuromuscular blockers like succinylcholine for intubation in Guillain-Barré syndrome due to the risk of a hyperkalemic response.

Both IV immunoglobulin and plasmapheresis shorten the time to recovery. Neither has been shown to be superior to the other, nor are they more efficacious when used together. There are adverse effects seen with both modalities of treatment. IV immunoglobulin has been associated with thromboembolism and aseptic meningitis; plasmapheresis is associated with hemodynamic instability, but a lower rate of relapse. In general, IV immunoglobulin is more widely available and less cumbersome to administer. Corticosteroids are of no benefit and may be harmful.1


Admit patients with acute Guillain-Barré syndrome to a unit where cardiac, respiratory, and neurologic functions can be monitored. Even if a patient does not initially meet the criteria for intubation, intensive care unit admission may still be indicated in order to avoid sudden, unmonitored respiratory failure.

 Managing Respiratory Failure in Guillain-Barré Syndrome

Indications for intubation

Vital capacity <15 mL/kg

Declining one breath count

Pao2<70 mm Hg on room air

Bulbar dysfunction (difficulty with breathing, swallowing, or speech)


Indications for admission to intensive care unit

Patients with 4 or more of the following findings: inability to stand, inability to lift the head, inability to lift the elbows, insufficient cough, time from symptom onset to hospital admission <7 days or elevated liver enzymes

Autonomic dysfunction

Bulbar dysfunction

Initial vital capacity <20 mL /kg

Initial negative inspiratory force less than –30 cm of water

Decrease of >30% of vital capacity or negative inspiratory force

Inability to ambulate

Treatment with plasmapheresis

Abbreviation: Pao2 = partial pressure of arterial oxygen.



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