The goal of this observational study is to estimate the prevalence of the use of protective ventilation with low tidal volume ventilation in the transition of spontaneous ventilation modes in patients with hypoxemic acute respiratory failure in ICUs in Latin America and its association with patient outcomes.

The main questions it aims to answer are:

• what is the prevalence of the use of low tidal volume ventilation (VT <8 mL/kg of predicted body weight) in the first 24 hours of spontaneous ventilation modes in patients with hypoxemic acute respiratory failure?
• Is there an association between the rate of adherence to low tidal volume ventilation in spontaneous ventilation modes and the ability to stay off ventilatory support and mortality?

Participants are patients with acute respiratory failure under mechanical ventilation. Investigators will collect data on the ventilatory parameters of participants

• 24 hours before they begin to be ventilated with spontaneous modes of ventilation
• during the first 24 hours of spontaneous ventilation

Investigators will collect several patient-centered clinical outcomes at 28 days after study inclusion, including ventilator-free days and mortality

Investigators will conduct a cohort study in Intensive Care Units (ICUs) across Latin America, aiming to include 422 patients with Hypoxemic Acute Respiratory Failure (ARF) and under invasive mechanical ventilation.

The goal of this observational study is to estimate the prevalence of the use of protective ventilation with low tidal volume ventilation in the transition of spontaneous ventilation modes in patients with hypoxemic acute respiratory failure in ICUs in Latin America

The primary objectives are to determine the prevalence of low tidal volume ventilation (VT < 8 mL/kg of predicted body weight) during the initial 24 hours of spontaneous ventilatory modes in patients diagnosed with hypoxemic ARF and its association with clinically important patient outcomes. Investigators are interested in assessing the rate of adherence to low tidal volume ventilation, defined as maintaining VT < 8 mL/kg of predicted body weight during the first 24 hours of ventilation in spontaneous mode.They are also interested in measuring the number of days that patients are alive and not receiving ventilatory support and survival at 28 days.

Investigators will also measure the proportion of patients experiencing significant asynchrony during the transition to spontaneous mechanical ventilation, who revert to sedation and controlled mechanical ventilation within the first 24 hours or at any point during mechanical ventilation.

Inclusion Criteria:

• Age > 18 years
• Patients with hypoxemic ARF, defined as a PaO2/FIO2 ratio <300 mmHg, under controlled invasive mechanical ventilation, with an expected duration of MV of at least 24h.
• Patients transitioning to spontaneous ventilation modes (PSV, PAV Plus, NAVA or APRV)

Exclusion Criteria:

• Tracheostomized patients.
• Decision not to maintain or add life support measures on the day of assessment (palliative care).
• Patient in ECMO.
• Air fistula or barotrauma that prevents adequate tidal volume monitoring.
• Severe injuries to the central nervous system that result in abolished or very high respiratory drive, for whom it is not possible to maintain protective tidal volume.

Patients with hypoxemic ARF, defined as a PaO2/FIO2 ratio <300 mmHg, under controlled invasive mechanical ventilation

data sharing will follow Institutional rules for patient data protection