Acute Respiratory Failure: Non-invasive Ventilation and High Flow Nasal Cannula

Non-invasive ventilation (NIV) is associated with improved outcomes among select patients with acute respiratory failure, primarily when due to acute exacerbations of chronic obstructive pulmonary disease and acute decompensated heart failure. This chapter presents an overview of NIV indications, risks, and benefits, as well as a limited practical overview of initial NIV settings and subsequent adjustments. NIV is relatively contraindicated in patients who cannot adequately protect their airway due to trauma, oral and respiratory secretions, or substantially altered mental status. However, patients who are altered due to hypercapnia may warrant a closely observed trial of NIV. Moderate evidence supports the use of NIV as a weaning strategy from invasive mechanical ventilation. While NIV has been studied in patients with acute respiratory failure due to pneumonia, these patients are at high risk for NIV failure with subsequent increased mortality, and invasive ventilation has traditionally been favored when these patients require mechanical respiratory support. High flow nasal cannula (HFNC) has emerged as an increasingly common support modality for acute hypoxic respiratory and may be used as a substitute or adjunct to NIV. The use of NIV and HFNC for patients with ARDS remains controversial, but may be feasible in a few select cases. Likewise, both NIV and HFNC can also be used for palliation of respiratory distress in certain patients with terminal disease processes.