 - Twice a day, the criteria of SBT are looked for. When they are present, a SBT is realized. If it is a success, the patient will be extube. If it is a failure, the patient will be reventilated in PSV or NAVA according to their group. A non-invasive ventilation preventive or of rescue can be administered post-extubation according to criteria. The reintubated criteria are also defined. 