Sedation and analgesia during noninvasive ventilation (NIV)

The use of noninvasive ventilation (NIV) has increased significantly in patients with acute respiratory failure (ARF) in order to prevent tracheal intubation and its complications. Unfortunately, NIV failure represents a frequent event, with rates that in some cases reach 40%. Mask intolerance, agitation, and delirium may lead to NIV failure, thus requiring endotracheal intubation. NIV failure rates are higher in patients without chronic obstructive pulmonary disease (COPD), and, when used in acute hypoxemic failure, its failure is associated with an increased mortality rate. The practice of sedation during NIV could be a valuable option for patients at risk of intubation. Sedation may decrease patient's discomfort and agitation which is often related to mask intolerance, without significant effects on respiratory drive, respiratory frequency, or hemodynamics. Sedation may also reduce transpulmonary pressure and the associated risk of exposing the patient to high tidal volume hence preventing ventilator-induced lung injury (VILI).