From the Guidelines
In Guillain-Barré Syndrome (GBS) patients, closely monitor vital capacity, maximum inspiratory and expiratory pressure, and assess the usage of accessory respiratory muscles as primary respiratory parameters, following the '20/30/40 rule' to predict the risk of respiratory failure 1. To monitor disease progression and potential complications in GBS patients, regular assessment of respiratory function is crucial, as not all patients with respiratory insufficiency will exhibit clinical signs of dyspnea. The following respiratory parameters should be monitored:
- Vital capacity
- Maximum inspiratory pressure
- Maximum expiratory pressure
- Usage of accessory respiratory muscles
- Single breath count, where a count of ≤19 predicts a requirement for mechanical ventilation The '20/30/40 rule' should be applied, where the patient is deemed at risk of respiratory failure if the vital capacity is <20 ml/kg, the maximum inspiratory pressure is <30 cmH2O, or the maximum expiratory pressure is <40 cmH2O 1. Additionally, monitoring for swallowing and coughing difficulties, as well as autonomic dysfunction via electrocardiography and monitoring of heart rate, blood pressure, and bowel and bladder function, is essential 1. It is also important to note that up to two-thirds of deaths in GBS patients occur during the recovery phase, primarily due to cardiovascular and respiratory dysfunction, emphasizing the need for vigilant monitoring during this phase 1. Another study also emphasizes the importance of early identification of patients at risk of respiratory failure, using tools such as the Erasmus GBS Respiratory Insufficiency Score (EGRIS) prognostic tool 1. However, the most recent and highest quality study, published in Nature Reviews Neurology in 2019, provides the '20/30/40 rule' as a clear guideline for monitoring respiratory parameters in GBS patients 1.
From the Research
Respiratory Parameters in GBS Patients
To monitor the respiratory status of patients with Guillain-Barré syndrome (GBS), several parameters should be followed:
- Vital capacity (VC) 2, 3, 4, 5, 6
- Maximal inspiratory pressure (MIP) 3, 5, 6
- Maximal expiratory pressure (MEP) 3
- Negative inspiratory force (NIF) 5
Predictors of Respiratory Failure
The following factors are associated with an increased risk of respiratory failure in GBS patients:
- Rapid disease progression 3, 4
- Bulbar dysfunction 3, 4
- Bilateral facial weakness 3
- Dysautonomia 3
- Vital capacity less than 20 mL/kg 3
- Maximal inspiratory pressure less than 30 cm H2O 3
- Maximal expiratory pressure less than 40 cm H2O 3
Monitoring and Management
Regular monitoring of respiratory parameters is crucial to identify patients at risk of respiratory failure:
- Daily measurements of VC, MIP, and MEP can help detect early signs of respiratory decline 3, 4
- Elective intubation should be considered in patients with rapidly progressive disease or severe bulbar dysfunction 2, 3
- Tracheostomy may be necessary in patients who require prolonged mechanical ventilation 2, 5