From the Guidelines
High flow nasal cannula (HFNC) is preferred over non-invasive ventilation (NIV) for the management of acute hypoxemic respiratory failure, as it provides improved patient comfort and physiologic advantages, such as improved oxygenation and ventilation, better pulmonary compliance, and reduced work of breathing. HFNC delivers heated and humidified oxygen at high flow rates (up to 60 L/min) through nasal prongs, creating a small amount of positive pressure while washing out anatomical dead space and reducing work of breathing 1. It's generally more comfortable and allows patients to eat, drink, and speak while receiving therapy. NIV, on the other hand, delivers positive pressure ventilation through a tight-fitting mask (such as CPAP or BiPAP) and provides higher, more consistent positive airway pressure levels. NIV can deliver both inspiratory pressure support (IPAP) and expiratory pressure (EPAP), making it more effective for conditions requiring significant ventilatory assistance like COPD exacerbations or cardiogenic pulmonary edema.
Some key differences between HFNC and NIV include:
- Mechanism of action: HFNC provides a small amount of positive pressure, while NIV provides higher, more consistent positive airway pressure levels
- Interface: HFNC uses nasal prongs, while NIV uses a tight-fitting mask
- Clinical applications: HFNC is suitable for mild to moderate respiratory failure, while NIV is typically chosen for more severe respiratory distress
- Patient comfort: HFNC is generally more comfortable and allows patients to eat, drink, and speak while receiving therapy
According to the European Respiratory Society task force panel, HFNC is suggested over NIV in hypoxaemic ARF, and either HFNC or NIV can be used in post-operative patients at high risk of pulmonary complications 1. The American College of Physicians also suggests using high-flow nasal oxygen rather than noninvasive ventilation in hospitalized adults for the management of acute hypoxemic respiratory failure 1.
In terms of clinical decision-making, the choice between HFNC and NIV depends on the patient's specific condition, the degree of respiratory compromise, and tolerance to the interface. HFNC is a suitable option for patients with mild to moderate respiratory failure, while NIV is typically chosen for more severe respiratory distress. Ultimately, the decision to use HFNC or NIV should be based on the individual patient's needs and clinical presentation, and should be guided by the latest evidence-based recommendations 1.
From the Research
Overview of High Flow Nasal Cannula (HFNC) and Non-Invasive Ventilation (NIV)
- HFNC and NIV are two different respiratory support techniques used in patients with respiratory failure.
- HFNC delivers a high flow of heated and humidified oxygen via the nasal route, while NIV uses bi-level positive pressure ventilation to support breathing.
Comparison of HFNC and NIV
- A study published in 2022 2 compared HFNC and NIV in patients with acute hypercapnic respiratory failure and found that HFNC did not reduce the risk of mortality or endotracheal intubation compared to NIV.
- Another study published in 2024 3 found that HFNC was not non-inferior to NIV in patients with acute exacerbations of chronic obstructive pulmonary disease (AECOPD) with acute-moderate hypercapnic respiratory failure, and resulted in a higher incidence of treatment failure.
- A study published in 2013 4 found that HFNC can provide adequate oxygenation for many patients with hypoxemic respiratory failure and may be an alternative to NIV for do-not-intubate patients.
Clinical Practice and Guidelines
- A clinical practice guideline published in 2020 5 recommended HFNC in hypoxemic respiratory failure compared to conventional oxygen therapy, and made conditional recommendations for HFNC following extubation and in postoperative patients.
- A survey of respiratory therapists published in 2024 6 found that while many therapists used HFNC in clinical settings, there was a lack of protocol adherence and significant challenges concerning HFNC implementation, highlighting the need for uniform, evidence-based guidelines and enhanced training.
Key Differences and Similarities
- The key difference between HFNC and NIV is the method of delivering oxygen and supporting breathing, with HFNC using a high flow of heated and humidified oxygen and NIV using bi-level positive pressure ventilation.
- Both HFNC and NIV are used in patients with respiratory failure, but the choice of technique depends on the specific clinical scenario and patient needs, as evidenced by studies 4, 2, 3.