Ventilator-associated pneumonia (VAP) continues to be a major cause of morbidity and mortality in the intensive care unit (ICU). Microaspiration of subglottic secretions accumulated above the endotracheal tube cuff is the primary route of bacterial entry into the lower respiratory tract.Therefore, removal of secretions from the subglottic spacehas been recommended as a preventive strategy to avoid microaspiration and VAP. In this context, whereas considerable literature exists on the use subglottic secretion drainage (SSD) in patients at risk for developing VAP, there is a lack of data on the bacterial growth in the subglottic fluid above the cuff.

The primary objective of the study will be to assess the value of subglottic secretion culture in predicting microbial flora of endotracheal aspirate samplein patients admitted to our ICU and under invasive mechanical ventilation for at least 48 hours. Secondary end-point will be to estimate the predictive value of subglottic secretion culture in identifying bacterial pathogens in the sub-population of patients who will develop VAP.

Inclusion Criteria:

• ≥18 years of age
• Invasive mechanical ventilation for at least 48 hours

Exclusion Criteria:

• age <18 years
• absence of informed consent
• pregnancy
• documented treatment-limitation orders in the patient's chart

ICU patients under invasive mechanica ventilations for at least 48 hours

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