Noninvasive ventilation for weaning and post extubation failure

Invasive Mechanical Ventilation (IMV) is a life-saving procedure not lacking from complications that enhances morbidity and mortality for intubated patients; therefore, it is important to minimize the duration of IMV. When the weaning fails, it is associated with an increased risk of death and prolonged intensive care unit (ICU) stay. Many investigators examined the possibility to wean patients ventilated invasively by Noninvasive ventilation (NIV). Several studies, tested, in patients affected by chronic respiratory disorders (ie, chronic obstructive pulmonary disease), the use of NIV as a weaning strategy after a failure of a spontaneous breathing trial; as a result, NIV reduced mortality, minimized ventilator-associated pneumonia, and shortened length of hospital stay. Further studies will be needed to assess the real impact of NIV on other form of respiratory failure.\Another major clinical problem in ICU is the post extubation failure. In fact, more than 15% of patients need to be reintubated within the first 72 hours. After a successful weaning trial,their prognosis is poor with an hospital mortality that exceeds 30%_40%. Randomized controlled studies have demonstrated that when NIV is applied to treat an overt episode of post extubation respiratory failure, it can be indeed harmful perhaps due to the delay of reintubation. Conversely, promising results were obtained using NIV to prevent the development of a post extubation failure in patients considered at high risk, particularly in those affected by hypercapnia at the time of a successful T-piece trial.