Guillain-Barré syndrome (GBS) is a rapidly progressive motor, sensory, and autonomic neuropathic disorder that may present to critical care with acute respiratory failure or bulbar palsy. Correct diagnosis and implementation of therapy usually results in favorable outcomes. This chapter considers management of GBS in the intensive care unit (ICU).
Pathogenesis
GBS is a prototype of a postinfectious autoimmune disease. Most patients develop GBS 1 to 3 weeks after a microbial infection. Histopathologically, GBS can be divided into acute inflammatory demyelinating polyneuropathy and acute motor axonal neuropathy based on the site of involvement of the inflammatory process within the peripheral nerve ( Fig. 66-1 ). Infections such as Campylobacter jejuni or cytomegalovirus induce the development of antibodies that subsequently bind to target antigens on the peripheral nerves as a result of molecular mimicry. These autoantibodies attach to the outer surface of Schwann cells or axonal membranes at the nodes of Ranvier, resulting in activation of the compliment system. This subsequently leads to the detachment of the paranodal myelin, resulting in motor conduction failure and muscle weakness.
Diagnosis
The presentation of GBS and related conditions can be heterogeneous, making the clinical diagnosis at times challenging. Classically, GBS presents with a rapidly progressive weakness of the extremities with variable involvement of the bulbar and respiratory muscles. There are localized subtypes of GBS that tend to involve only a specific group of muscles ( Table 66-1 ). These include (1) the pharyngeal-cervical-brachial subtype with involvement of the bulbar and proximal upper limb muscles; (2) the paraparetic subtype; and (3) the bifacial variant, which presents with isolated facial weakness. Miller Fisher syndrome (MFS), which presents with ophthalmoplegia, ataxia, and areflexia, is a variant of GBS. MFS may present in incomplete form as acute ophthalmoplegia or acute ataxic neuropathy. Bickerstaff brainstem encephalitis, which presents with hypersomnolence, ophthalmoplegia, and ataxia, is a central nervous system subtype of MFS. Some of these patients go on to have involvement of other groups of muscles and thus phenotypically resemble the classical type of GBS. Pharyngeal-cervical-brachial weakness, MFS, and Bickerstaff encephalitis are often misdiagnosed as having brainstem stroke, myasthenia gravis, botulism, or Wernicke encephalopathy ( Table 66-2 ).
Pattern of Weakness | Ataxia | Hypersomnolence | |
---|---|---|---|
Guillain-Barré syndrome | Four limbs | Yes | |
| Bulbar/cervical/upper limbs | ||
Incomplete form | |||
| Bulbar | ||
| Facial | ||
| Lower limbs | ||
Miller Fisher syndrome | Ophthalmoplegia | Yes | |
Incomplete forms | |||
| Ophthalmoplegia | ||
| No weakness | Yes | |
| Ptosis | ||
| Paralytic mydriasis | ||
Central nervous system subtype | |||
| Ophthalmoplegia | Yes | |
Incomplete form | |||
| No weakness | Yes |
Guillain-Barré Syndrome
|
Miller Fisher Syndrome, Bickerstaff Brainstem Encephalitis, and Pharyngeal-Cervical-Brachial Weakness
|
Paraparetic Variant
|
Bifacial weakness with paraesthesias
|
Nerve conduction studies and cerebrospinal fluid (CSF) analysis are not always conclusive, especially at admission, and the diagnosis should be based on clinical grounds ( Table 66-3 ). A lumbar puncture is performed primarily to rule out infectious processes, such as Lyme disease, or malignancies, such as lymphoma. Albuminocytologic dissociation (elevation in CSF protein [>0.55 g/L] without an elevation in white blood cells) is present in approximately 50% of patients with GBS during the first week of illness. Brain and spinal imaging studies are unhelpful. A history of antecedent infectious symptoms such as sore throat, cough, or diarrhea is useful for the clinical diagnosis as well as the presence of distal paraesthesias immediately before, and at the onset of, weakness or ataxia.
Core Clinical Features | Supportive Features |
---|---|
| |
| |
| |
| |
| |
|
|
| |
| |
| |
| |
| |
|