压力支持自主呼吸试验后一小时正压通气：一项随机临床试验

As soon as the success of the spontaneous breathing trial is confirmed, the patient will be submitted to one-hour positive pressure ventilation using the previous ventilatory parameters and, afterwards, extubated.

The patient will be extubated immediately (up to 10 minutes) after the success of the spontaneous breathing trial.

Extubation failure is defined as a composite endpoint of reintubation or death within 7 days after randomization

Ventilator-free days are defined as the number of days alive and free from invasive mechanical ventilation from randomization through Day 28 after randomization. If a patient dies before day 28, the ventilator-free days will be counted as zero. If a patient is reintubated and returns to mechanical ventilation and later is extubated again and remains in unassisted breathing until day 28, the ventilator-free days will be counted from the end of the last period of assisted breathing until day 28. An invasive mechanical ventilation period of less than 24 hours for surgical purposes will count as 1 ventilator-free day. Patients discharged from the hospital in unassisted breathing before 28 days will be considered alive and free from mechanical ventilation for the remaining days up to 28 days. Patients transferred to another hospital or healthcare unit will be followed up until day 28 to assess this outcome.

Hospital-free days are defined as the number of days alive and out of the hospital from randomization through Day 28 after randomization. If a patient dies before day 28, the hospital-free days will be counted as zero. Patients discharged from the hospital in unassisted breathing before 28 days will be considered alive and free from hospital for the remaining days up to 28 days. Patients transferred to another hospital or healthcare unit will be followed through day 28 to ascertain this outcome.

All-cause mortality from randomization through day 28

Ventilatory support-free days are defined as the number of days alive and free from any ventilatory support (invasive or noninvasive) from randomization through day 28. Any use of invasive mechanical ventilation for any duration during a calendar day will count as 1 day with ventilatory support (i.e., not free). Use of noninvasive ventilatory support (noninvasive ventilation or high-flow nasal cannula) for ≥6 hours in any calendar day will count as 1 day with ventilatory support. Participants who die before day 28 will be assigned 0 ventilatory support-free days. If reintubation occurs and the participant later achieves unassisted spontaneous breathing again, ventilatory support-free days will be counted from the end of the last assisted-breathing period through day 28, provided the participant remains alive and free from ventilatory support.

Extubation failure is defined as a composite endpoint of reintubation or death within 2 days after randomization

Composite endpoint of reintubation or death within 28 days after randomization

ICU-free days are defined as the number of days alive and out of the intensive care unit from randomization through day 28. If a patient dies before day 28, the ICU-free days will be counted as zero. Patients discharged from the hospital in unassisted breathing before 28 days will be considered as alive and free from ICU for the remaining days up to 28 days. Patients transferred to another hospital or healthcare unit will be followed up until day 28 to assess this outcome.

All-cause mortality occurring from randomization until hospital discharge (death before hospital discharge)

All-cause mortality occurring from randomization until ICU discharge (death before ICU discharge)