Use of Noninvasive Ventilation to Facilitate Weaning fromMechanical Ventilation

Abstract

Noninvasive positive-pressure ventilation (NIV), applied through various mask interfaces, improves outcomes in patients with acute respiratory failure secondary to acute exacerbation of chronic obstructive pulmonary disease (COPD), acute cardiogenic pulmonary edema, and hypoxemic respiratory failure with pulmonary infiltrates in immunocompromised patients. NIV has also been used to prevent, or treat, respiratory failure in patients undergoing planned extubation from mechanical ventilation [1]. Randomized controlled trials suggest that NIV may not be effective when applied to a heterogeneous group of patients with extubation failure, although a case control study suggests this therapy may be effective for patients with COPD with extubation failure [2, 3]. Similarly, NIV seems not to prevent extubation failure (defined as the need for reintubation) when it is applied nonselectively to all extubated patients [4]. By contrast, NIV improves outcome (decreased reintubation, decreased pneumonia, shorter duration or mechanical ventilation and length of stay, improved survival) when it is used as preventive therapy in cohorts of patients deemed to be at high risk for extubation failure [5, 6]. With the exception of some patients in the Jiang study, NIV was used in these investigations only when a patient had successfully passed a spontaneous breathing trial (SBT), indicating that mechanical ventilatory support was no longer required. These studies raise the question of whether NIV can be used in the patient who is ready to initiate weaning but who is not yet able to tolerate an SBT. In other words, can NIV be used to facilitate weaning?