Ventilator-associated Tracheobronchitis Initiative to Conduct Antibiotic Evaluation

Inclusion Criteria: * Admission to one of the participating ICUs * Invasive Mechanical ventilation ≥ 48 hours * Available chest imaging of screening day * Clinical diagnosis of VAT, defined by the presence of: 1. Temperature \>38.0°C or \<36°C OR leukocytes \>12000/mL or \<4000/mL or presence \>10% of immature forms, AND 2. Onset of purulent tracheal secretion, or change in characteristics of the secretion, or increase in the amount of respiratory secretion, or increased need for aspiration * Culture of tracheal secretion from the day of screening under analysis or collected for analysis Exclusion Criteria: * Pregnant or lactating women * Indication of use of antibiotics or use of systemic antibiotics for any indications at the time of screening * Hemodynamic instability, defined as hypotension unresponsive to volume expansion or increase in vasopressor dose \> 0.1mcg/kg/min of noradrenaline or equivalent in the past 6 hours * Worsening of gas exchange, defined as an increase in the fraction of inspired oxygen ≥ 20% or an increase in positive end-expiratory pressure (PEEP) ≥ 3 cm of water after a stability period ≥ 2 days * Prolonged mechanical ventilation, defined by use of invasive mechanical ventilation for 21 days or more * Presence of pulmonary radiological image suggestive of new infectious infiltrate * Previous lung disease that makes radiological interpretation for the diagnosis of VAP difficult * Previous diagnosis of ventilator associates pneumonia (VAP) during hospitalization * Neutropenic patients (neutrophils \<1000/mL) * Known severe immunosuppression * Tracheostomized patients at the time of screening * Inclusion in the study in the past 30 days * Expected limitation of care or early withdrawal of supportive therapies (\< 7 days) * Patients with a survival expectancy of less than 48 hours * Refusal of consent to participate in the study