What are the uses and advantages of a helmet mask in continuous positive airway pressure (CPAP) and non-invasive ventilation (NIV)?

Helmet Mask: Uses and Advantages in CPAP and NIV

Helmet masks should be considered first-line interface options for delivering non-invasive ventilation (NIV) and continuous positive airway pressure (CPAP) due to their superior tolerability, reduced room contamination, and improved clinical outcomes including reduced intubation rates and mortality. 1

Key Advantages of Helmet Masks

• Better patient tolerability for prolonged use compared to face masks, allowing for extended therapy without discomfort, which is particularly important in acute respiratory failure 1, 2

• Reduced risk of aerosol generation and viral transmission during infectious disease outbreaks like COVID-19, minimizing the nebulization of infected material and increasing healthcare worker safety 1, 2

• Lower intubation rates compared to conventional face mask NIV, with studies showing a significant reduction from 61.5% with face masks to 18.2% with helmets in ARDS patients 3

• Decreased mortality with helmet NIV showing a 22.3% absolute reduction in 90-day mortality compared to face mask NIV in ARDS patients 3

• Less resistance to patient breathing effort compared with conventional masks, improving patient-ventilator synchrony 1

• Better seal around the neck with reduced air leaks, allowing for more effective delivery of positive pressure 2, 4

Clinical Applications

Recommended Clinical Scenarios:

• Acute hypoxemic respiratory failure including COVID-19 pneumonia 1, 2
• Acute cardiogenic pulmonary edema 2, 5
• Immunocompromised patients with respiratory failure 2, 4
• Acute chest trauma patients requiring respiratory support 2
• Palliative care settings where comfort and communication are important 2

Cautions and Limitations:

• Carbon dioxide rebreathing risk - particularly concerning in hypercapnic respiratory failure such as COPD exacerbations 4, 5, 6
• Patient-ventilator asynchrony may occur if not properly configured 5
• Neck skin ulcers reported in approximately 6.8% of patients with prolonged use 3

Technical Considerations

• Proper setup requires:

  • An appropriate antimicrobial filter to limit exhaled air dispersion 1
  • Adequate flow rates to prevent CO₂ rebreathing 4, 5
  • Monitoring for patient-ventilator synchrony, especially during pressure support ventilation 5

• Safety measures during infectious diseases:

  • Use in negative-pressure rooms or dedicated isolation areas 1
  • Healthcare providers should wear full PPE including eye protection, N95 respirators, gloves, and gowns 1

Comparison with Other Interfaces

• Versus face masks:

  • Helmet CPAP/NIV shows better tolerance for extended periods 1, 2
  • Lower intubation rates in ARDS patients (18.2% vs 61.5%) 3
  • Increased ventilator-free days (28 vs 12.5 days) 3
  • Reduced 90-day mortality (34.1% vs 56.4%) 3

• When helmet NIV cannot be used:

  • Hudson and Venturi masks or face masks with double circuits and expiratory valves are alternatives 1
  • If single circuit face mask is needed, it should be equipped with integrated exhalation port rather than vented masks 1

Evidence-Based Recommendations

• Italian and German guidelines recommend helmet NIV as first choice among interface modes, especially during infectious disease outbreaks 1

• For CPAP application: Helmet CPAP provides valid pulmonary support with better tolerability and reduced room contamination 1

• For monitoring: Close observation is essential as deterioration can occur rapidly; if no improvement is seen within 1-2 hours, consider invasive ventilation 1

• For optimal PEEP delivery: Helmets allow for effective delivery of higher PEEP levels, which may contribute to reduced intubation rates 1

The helmet interface represents a significant advancement in non-invasive respiratory support, offering particular benefits in hypoxemic respiratory failure while requiring careful attention to technical setup to avoid complications like CO₂ rebreathing.