Effect of Gravity on Tracheal Colonization During Mechanical Ventilation in Infants

Ventilator-associated pneumonia (VAP) is the leading cause of death among all nosocomial infections in ventilated patients. Once intubated, the risk of pneumonia in hospitalized patients is increased 3-10 fold; almost 90% of hospital-acquired pneumonia occurs in intubated patients. Each episode of VAP is associated with 7-9 days of additional hospital stay with an estimated increase in cost of care that exceeds $40,000. In an effort to control VAP, several studies were conducted including oral and gastric decontamination with antibiotics, rotation of the bed, and local instillation of antibiotics via endotracheal tube. Despite such efforts, VAP is still a major complication for intubated patients.

The effect of gravity on bacterial colonization of the endotracheal tube was recently explored in an animal study that was conducted at the United States National Institutes of Health. The study demonstrated a significantly lower tracheal colonization and decreased alveolar contamination in ventilated sheep when positioned on their side allowing for tracheal drainage by gravity. Such findings have not been validated in clinical practice and the need for clinical trials studying the effect of lateral positioning have been demanded. Therefore, we aimed our randomized controlled trial to test the hypothesis that intubated infants who are positioned on their side are at lower risk for contracting microbes in their trachea when compared to those in a supine position.