What are the principles of Non-Invasive Ventilation (NIV)?

From the Guidelines

Non-invasive ventilation (NIV) should be used to support patients with respiratory insufficiency, prioritizing proper patient selection, comfort, and minimizing air leaks, as outlined in the most recent guidelines 1. The primary principle of NIV is to improve gas exchange by increasing functional residual capacity, reducing work of breathing, and improving alveolar ventilation.

Key Principles of NIV

• NIV delivers positive pressure ventilation through a mask interface rather than an invasive airway, typically using either continuous positive airway pressure (CPAP) or bilevel positive airway pressure (BiPAP) 1.
• Proper patient selection is crucial, with best results seen in COPD exacerbations, cardiogenic pulmonary edema, and immunocompromised patients with respiratory failure.
• The interface selection (nasal mask, full face mask, or helmet) should prioritize comfort and minimize air leaks.
• Initial settings typically start with low pressures (IPAP 8-12 cmH2O, EPAP 4-5 cmH2O for BiPAP; or CPAP 5-10 cmH2O) and are gradually titrated based on patient response, work of breathing, and blood gas measurements.

Monitoring and Adjustments

• Close monitoring is essential during the first hours of therapy, watching for signs of NIV failure such as worsening respiratory distress, deteriorating blood gases, or hemodynamic instability, which would indicate the need for intubation 1.
• Patient comfort and synchrony with the ventilator are fundamental to NIV success, often requiring adjustments to settings and appropriate sedation management.

Important Considerations

• NIV should not be used as a substitute for tracheal intubation and invasive ventilation when the latter is clearly more appropriate 1.
• A decision about intubation if NIV fails should be made early in each patient, taking into consideration the severity of the underlying disease and previous level of disability, and documented in the notes 1.

From the Research

Principles of Non-Invasive Ventilation (NIV)

The principles of NIV involve the use of positive intrathoracic pressure through an interface to support respiratory function in patients with acute respiratory failure. Key aspects of NIV include:

• Choice of interface: The selection of an appropriate interface, such as a nasal or oronasal mask, helmet, or high-flow nasal cannula, is crucial for patient comfort and tolerance 2, 3, 4, 5.
• Ventilatory setting: The choice of ventilatory setting, including pressure-support ventilation (PSV), controlled ventilation, and electrical activity of the diaphragm (EADi)-driven ventilation, can impact patient comfort and outcomes 2, 5.
• Patient comfort: Strategies to enhance patient comfort, such as sedation, prone positioning, and careful selection of fixing systems, are essential for the success of NIV 2, 5.
• Indications: NIV is commonly used in patients with acute exacerbations of chronic obstructive pulmonary disease (COPD), acute cardiogenic pulmonary edema, and immunocompromised patients with respiratory failure 3, 4, 5.
• Monitoring and management: Close monitoring and proactive management of patients receiving NIV are critical for optimizing outcomes and minimizing complications 2, 3, 4, 5.

Key Considerations

Some key considerations in the use of NIV include:

• The importance of early initiation of NIV in patients with acute respiratory failure to reduce the risk of intubation and improve outcomes 4.
• The need for careful selection of patients and interfaces to ensure optimal tolerance and effectiveness of NIV 2, 3, 4, 5.
• The potential benefits of NIV in reducing morbidity and mortality associated with invasive ventilation, particularly in patients with COPD exacerbations and acute cardiogenic pulmonary edema 4.
• The importance of ongoing monitoring and adjustment of NIV settings to ensure optimal patient comfort and outcomes 2, 5.