Management of Bulbar Involvement with Acute Cerebellar Signs
Patients with bulbar involvement and acute cerebellar signs require immediate placement in an intensive care unit (ICU) or high-dependency unit (HDU) with close neurological monitoring, as deterioration can be rapid and potentially fatal.
Initial Assessment and Stabilization
Airway Management
- Immediate airway assessment is critical as bulbar dysfunction compromises airway protection 1
- Indications for endotracheal intubation include:
- Decreased consciousness
- Inability to maintain patent airway
- Pooling secretions
- Hypoxemia or hypercarbic respiratory failure
- Recent aspiration 1
- Rapid sequence intubation is preferred when needed 1
Respiratory Support
- Supplemental oxygen should be provided to maintain saturation >94% 1
- Consider controlled ventilation as triggering may be ineffective with neuromuscular weakness 1
- Monitor for rapid desaturation during breaks from ventilatory support, which indicates worsening 1
Neurological Monitoring
- Frequent monitoring of level of arousal and new brainstem signs (Class I; Level of Evidence C) 1
- Watch for pupillary changes (anisocoria, pinpoint pupils) and loss of oculocephalic responses 1
- Monitor for irregular breathing patterns and sudden apnea, indicating lower brainstem compression 1
Medical Management
Cerebellar Swelling Management
- Elevation of head of bed to 30° 1
- Osmotic therapy is reasonable for clinical deterioration (Class IIa; Level of Evidence C) 1
- Options include:
- Mannitol (1 g/kg of 20%)
- Hypertonic saline (varying concentrations: 3%, 7.5%, 23%)
- Options include:
- Avoid hypo-osmolar fluids; use isotonic saline as maintenance fluid 1
- There is insufficient evidence for hypothermia, barbiturates, or corticosteroids (Class III; Level of Evidence C) 1
General Measures
- Ensure sufficient cerebral oxygenation 1
- Treat hyperthermia 1
- Correct hypovolemia with isotonic fluids 1
- Avoid oral intake of food and fluids 1
- Treat hyperglycemia >8 mmol/l 1
- Avoid antiplatelet agents if surgical intervention is likely 1
Surgical Management
Cerebellar Infarction
- Early neurosurgical consultation is essential for patients with cerebellar involvement 1
- Indications for surgical intervention include:
- Clinical signs of brainstem compression
- Neurological deterioration
- Obstructive hydrocephalus
- Decreased level of consciousness (GCS <12)
- Decline in GCS ≥2 points 1
- Radiographic indications: fourth ventricular compression and hydrocephalus 1
Surgical Options
- Suboccipital decompressive craniectomy for space-occupying cerebellar infarction 1
- External ventricular drainage may be needed for hydrocephalus 1
- Do not delay intervention if deterioration occurs, as outcomes are better with early surgery 1
Special Considerations
Bulbar Dysfunction Complications
- Chronic malnutrition from bulbar weakness affects respiratory muscle function 2
- Upper airway obstruction may occur due to laryngeal and pharyngeal muscle weakness 2
- Inadequate peak cough flows prevent clearing of airway debris 2
- Dysphagia increases risk of aspiration pneumonia 2
- Abnormal respiratory patterns during swallow are common 2
Post-Acute Management
- Nocturnal NIV should be continued following acute episode pending discussion with home ventilation service 1
- Tracheostomy may be needed in patients with persistent bulbar dysfunction 1
- Weaning from ventilation depends on alertness, cough/gag reflex, and eye movements 1
Pitfalls and Caveats
- Bulbar dysfunction makes non-invasive ventilation (NIV) more difficult or impossible 1
- Deterioration in patients with bulbar involvement and cerebellar signs may be very sudden 1
- Volitional respiratory function tests can be inaccurate in patients with bulbofacial weakness 2
- Advanced brainstem dysfunction (locked-in syndrome) is a predictor of unfavorable outcome in cerebellar infarctions 1
- Do not wait for acidosis to develop before initiating ventilatory support 1