A nurse is caring for a client who has acute respiratory distress syndrome and is receiving mechanical ventilation. Which of the following actions should the nurse take to prevent ventilator-associated pneumonia?

Choice A reason: Suctioning the endotracheal tube every hour is not recommended as a routine preventive measure. Frequent suctioning can cause mucosal trauma, increase the risk of infection, and lead to hypoxemia. Suctioning should be performed only when clinically indicated, such as when secretions are audible or oxygen saturation decreases. Therefore, this option is incorrect because it does not align with evidence-based practices for preventing ventilator-associated pneumonia. Choice B reason: Keeping the head of the bed flat increases the risk of aspiration of gastric contents and oral secretions, which can lead to ventilator-associated pneumonia. The recommended practice is to elevate the head of the bed to 30–45 degrees to reduce aspiration risk. Thus, this option is incorrect because it promotes conditions that increase infection risk rather than prevent it. Choice C reason: Turning the client every 4 hours is important for preventing complications such as pressure injuries and improving overall circulation, but it is not a primary intervention for preventing ventilator-associated pneumonia. While repositioning can help mobilize secretions, it is not considered a direct evidence-based measure for reducing pneumonia risk. Therefore, this option is supportive but not the best answer. Choice D reason: Performing oral care with chlorhexidine is a proven intervention to reduce bacterial colonization in the oropharynx, which is a major source of pathogens that cause ventilator-associated pneumonia. Chlorhexidine oral care decreases microbial load and lowers the incidence of pneumonia in mechanically ventilated patients. This is the correct answer because it directly addresses the prevention of ventilator-associated pneumonia through targeted infection control.