Postextubation Use of Noninvasive Respiratory Support in Severely Obese Patients

Patients with obesity are at risk of developing respiratory failure due to reduced lung volumes and chest wall compliance. Obesity is one of the easily identifiable, contributing factors of extubation failure that often leads to prolonged mechanical ventilation use and ICU stay. The early application of noninvasive respiratory support, especially NIV, has been shown to reduce reintubation rates in obese patients in a small, non-randomized study. However, prolonged use of NIV is often associated with decreased patient compliance and increased incidence of skin breakdown. HFNC is a noninvasive strategy that is comfortable, uses a nasal cannula and provides a high flow rate to meet the patient's inspiratory flow demand and thereby reduce work of breathing. The purpose of this RCT will be to determine the effects of using NIV alternating with HFNC for reducing the treatment failure rate compared with HFNC alone in extubated patients with severe obesity. We hypothesize that early, prophylactic use of NIV alternating with HFNC will decrease the risk of respiratory failure (treatment failure) in severely obese patients.