Ventilator-associated pneumonia

Pneumonia that occurs in people on mechanical ventilation

Ventilator-associated pneumonia (VAP) is a type of pneumonia that occurs in people who are on mechanical ventilation through an endotracheal tube or tracheostomy for at least 48 hours. It is a significant concern in intensive care units (ICUs) due to its association with increased morbidity and mortality.

Causes

VAP is caused by the invasion of the lower respiratory tract and lung parenchyma by microorganisms. The most common pathogens include bacteria such as Staphylococcus aureus, Pseudomonas aeruginosa, and Klebsiella pneumoniae. The risk of VAP increases with the duration of mechanical ventilation.

Pathophysiology

The pathogenesis of VAP involves the aspiration of oropharyngeal secretions, colonization of the aerodigestive tract, and the formation of biofilms on the endotracheal tube. These factors contribute to the development of infection in the lower respiratory tract.

Diagnosis

The diagnosis of VAP is challenging and often involves a combination of clinical, radiological, and microbiological criteria. Common diagnostic tools include chest X-rays, bronchoalveolar lavage, and sputum cultures. The presence of new or progressive infiltrates on chest X-ray, along with clinical signs such as fever, purulent sputum, and leukocytosis, may suggest VAP.

Chest X-ray showing pneumonia

Prevention

Preventive strategies for VAP include maintaining proper hand hygiene, elevating the head of the bed, daily sedation vacations, and implementing ventilator care bundles. The use of subglottic secretion drainage and selective digestive decontamination may also reduce the incidence of VAP.

Treatment

The treatment of VAP typically involves the administration of antibiotics tailored to the suspected or confirmed pathogens. Empirical therapy is often initiated based on local antibiograms and adjusted according to culture results. Supportive care, including adequate oxygenation and fluid management, is also crucial.

Prognosis

The prognosis of VAP varies depending on the patient's underlying condition, the causative organism, and the timeliness of appropriate treatment. VAP is associated with increased length of stay in the ICU and higher healthcare costs.

Related pages

• Pneumonia
• Mechanical ventilation
• Intensive care unit