What are the management strategies for a patient with Amyotrophic Lateral Sclerosis (ALS) using Volume-Controlled Ventilation (VCV) for breathing support?

Management of ALS Patients Using Volume-Controlled Ventilation (VCV)

For patients with Amyotrophic Lateral Sclerosis (ALS) using Volume-Controlled Ventilation (VCV), individualized respiratory management strategies should be implemented with regular monitoring and adjustments to optimize ventilation, manage secretions, and address nutritional needs to improve survival and quality of life.

Respiratory Assessment and Monitoring

• Perform pulmonary function tests (PFTs) at minimum every 6 months to track respiratory decline, including measurements of maximum inspiratory pressure (MIP), maximum expiratory pressure (MEP), and forced vital capacity (FVC) 1
• Screen for sleep disturbances at each clinical visit as these are important indicators of respiratory insufficiency 1
• Use waveform capnography to confirm and continuously monitor airway and ventilation status during respiratory support 2

Optimizing VCV Settings

• VCV may be particularly advantageous in situations where the inner diameter of the airway decreases due to increased sputum production 3
• Adjust ventilator parameters based on:
  • Patient comfort and tolerance 2
  • Sleep quality assessment 2
  • Digital downloads from the ventilator 2
  • Monitoring of unintentional leaks 2
  • Oximetry readings (and capnography when available) 2

Management of Secretions

• Implement lung volume recruitment techniques (breath stacking) for patients with reduced lung function or cough effectiveness 1
• Consider mechanical insufflation-exsufflation devices for secretion clearance 1
• For sialorrhea (excessive saliva), start with anticholinergic medication as first-line therapy 1
• Consider botulinum toxin therapy to salivary glands if anticholinergics are inadequate or poorly tolerated 1

Supplemental Ventilation Strategies

• Consider mouthpiece ventilation (MPV) as a daytime ventilatory support option for patients with preserved bulbar function 2, 1
• MPV allows ventilatory support through an angled mouthpiece and has been used successfully to avoid tracheostomy 2
• For patients with bulbar impairment, special attention to interface selection and ventilator settings is crucial for NIV tolerance and effectiveness 4

Nutritional Support

• Screen for malnutrition (BMI, weight loss) at diagnosis and every 3 months during follow-up 1
• Consider percutaneous endoscopic gastrostomy (PEG) for nutritional support when dysphagia develops 2
• PEG is recommended as the preferred approach for gastrostomy, with radiologically inserted gastrostomy (RIG) as an alternative for more frail patients 2

Progression of Respiratory Support

• Consider transitioning to invasive mechanical ventilation via tracheostomy when:
  • NIV fails or is not tolerated 2, 1
  • Bulbar function worsens significantly 1
  • Frequent aspiration occurs despite management 1
  • Insufficient cough persists despite adequate secretion management 1
  • Recurrent chest infections occur despite secretion management 1

Monitoring Effectiveness of VCV

• Assess NIV tolerance and effectiveness regularly, as tolerance has been identified as an independent predictor of survival 5
• Monitor mechanically assisted cough peak flow and percentage of time with SpO2 < 90% at night while using NIV, as these are factors associated with tolerance of VCV NIV 5
• Evaluate for correction of leaks, management of obstructive apnea, and adaptation to the patient's degree of ventilator dependence to improve prognosis 6

Common Pitfalls and Considerations

• Avoid delaying NIV initiation in patients with respiratory symptoms, as early intervention may improve outcomes 2, 1
• Be aware that progressive bulbar symptoms may limit the use of non-invasive options 2
• Recognize that achieving real-world adherence to NIV in ALS patients requires significant respiratory therapist involvement and follow-up 7
• Consider switching between ventilation modes based on clinical situation - PCV may be beneficial when increased leakage volume prevents adequate tidal volume delivery 3