Consider in 3 main conditions:

• Acute pulmonary edema associated with heart failure.
• COPD exacerbation.
• Asthma – less evidence for value.

Patients must be able to breathe by themselves as this does not provide mechanical breathing.

Contraindications:

• Need immediate intubation.
• Uncooperative patient – altered mental status, anxiety.
• Risk of aspiration – vomiting, hematemesis.
• Hemodynamic instability.

• Non-invasive ventilation can improve ventilation, oxygenation, and work of breathing leading to improved outcomes and reduced intubation/ventilator use.
• Shorter ICU stays.

Non-invasive ventilation can involve supplementing oxygen with nasal cannulas, oronasal face masks, and helmets.

Some common forms of non-invasive ventilation include:

• Continuous positive airway pressure (CPAP).
  • used for acute pulmonary edema, asthma, obstructive sleep apnoea (OSA).
• Bilevel positive airway pressure (BIPAP), inspiratory positive airway pressure (IPAP), and expiratory positive airway pressure (EPAP).

Table 1. Considerations for Non-Invasive Ventilation

Closely monitor respiratory rate, level of consciousness and PaO₂ to FIO₂ trajectory in case of potential failure.

• Healthcare teams should be experienced with non-invasive respiratory support and ventilation settings for greater utility.
• Treatment for COPD, obesity hypoventilation syndrome, and cardiogenic pulmonary edema should first involve a method of non-invasive ventilation that the team is comfortable in, with early monitoring of signs of failure.
• Considerations in selecting non-invasive ventilation device although most people
  • High flow nasal cannula
    • More comfortable.
    • Can use in prone position.
    • Least effective delivery of PEEP.
  • Face mask
    • More effective delivery of PEEP than high flow nasal cannula.
  • Helmet
    • Most effective delivery of PEEP.
    • Greater tolerance, fewer breaks off device needed.
    • Can deliver CPAP without ventilator if in low resource setting.
    • May be able to overcome airway closure or auto-PEEP.
    • More claustrophobic.
    • Challenging to use in prone position.
    • Challenging to perform investigations.
    • Lengthier transition to intubation.
    • Greater learning curve.

1. • https://oce.ovid.com/article/00003246-201602000-00006/HTML (Acute Simplified Physiology Score II)
   • https://link.springer.com/article/10.1007/s00134-016-4601-3 (HACOR Score)
   • https://www.uptodate.com/contents/noninvasive-ventilation-in-adults-with-acute-respiratory-failure-benefits-and-contraindications?search=noninvasive%20ventilation&source=search_result&selectedTitle=1~150&usage_type=default&display_rank=1#H96523994
   • https://www.uptodate.com/contents/noninvasive-ventilation-in-adults-with-acute-respiratory-failure-practical-aspects-of-initiation?search=noninvasive%20ventilation&source=search_result&selectedTitle=2~150&usage_type=default&display_rank=2
   • https://www.ebmedicine.net/topics/respiratory/pediatric-noninvasive-ventilation
   
   

1. Penuelas O, Frutos-Vivar F, Esteban A. Noninvasive positive-pressure ventilation in acute respiratory failure. Canadian Medical Association Journal. 2007;177(10):1211–8. doi:10.1503/cmaj.060147

   
   

2. Munshi L, Mancebo J, Brochard LJ. Noninvasive respiratory support for adults with acute respiratory failure. New England Journal of Medicine. 2022;387(18):1688–98. doi:10.1056/nejmra2204556

   
   

3. Digby GC, Keenan SP, Parker CM, Sinuff T, Burns KE, Mehta S, et al. Noninvasive ventilation practice patterns for acute respiratory failure in Canadian tertiary care centres: A descriptive analysis. Canadian Respiratory Journal. 2015;22(6):331–40. doi:10.1155/2015/971218

   
   

4. Keenan SP, Sinuff T, Burns KE, Muscedere J, Kutsogiannis J, Mehta S, et al. Clinical practice guidelines for the use of noninvasive positive-pressure ventilation and noninvasive continuous positive airway pressure in the acute care setting. Canadian Medical Association Journal. 2011;183(3). doi:10.1503/cmaj.100071