Ventilator-associated events (VAEs) are complications that occur in patients receiving mechanical ventilation and include conditions such as ventilator-associated pneumonia (VAP), pulmonary edema, and atelectasis. The CBIC Certified Infection Control Exam Study Guide (6th edition) emphasizes that patient positioning plays a critical role in preventing aspiration and subsequent respiratory complications in mechanically ventilated patients.

Maintaining patients in a supine position, particularly during transport, increases the risk of aspiration of gastric contents and oropharyngeal secretions. Aspiration is a well-recognized contributing factor to the development of VAEs because it can lead to infection, inflammation, and worsening oxygenation. The Study Guide recommends maintaining the head of the bed elevated (generally 30–45 degrees) whenever feasible, including during care activities and transport, to reduce aspiration risk.

The other options listed—daily sedation vacation, daily weaning assessment, and daily oral care with chlorhexidine—are evidence-based prevention strategies that are part of ventilator care bundles. These interventions are designed to reduce the duration of mechanical ventilation, improve pulmonary function, and decrease microbial colonization, all of which lower the risk of VAEs rather than contribute to them.

Therefore, supine positioning during transport is the most likely factor contributing to an increase in ventilator-associated events and represents a deviation from recommended infection prevention practices.