One-Hour Positive Pressure Ventilation After a Pressure Support Spontaneous Breathing Trial

This is a randomized, open, multicenter, pragmatic, adaptive clinical trial with intention-to-treat analysis. The study will compare two weaning strategies from mechanical ventilation in critically ill patients admitted to intensive care units, with more than 72 hours of mechanical ventilation and with a successful spontaneous breathing trial on pressure support. Immediately after a successful spontaneous breathing trial, eligible patients will be randomized into 2 groups that will be treated according to one of the following interventions:1) One-hour positive pressure ventilation: as soon as the success of the spontaneous breathing trial is confirmed, the patient is submitted to mechanical ventilation for 1 hour using the previous ventilatory parameters and, afterwards, extubated.2) Immediate extubation: the patient is extubated immediately after the success of the spontaneous breathing trial.