Accuracy and applications of lung ultrasound to diagnose ventilator-associated pneumonia: a systematic review.

Abstract

Background: Ventilator-associated pneumonia (VAP) is a frequent complication in mechanically ventilated patients, contributing to high morbidity, mortality, and healthcare costs. Lung ultrasound (LUS) offers potential advantages as a diagnostic tool but is not yet widely established for VAP diagnosis. Objective: To assess the evidence of LUS for diagnosing ventilator-associated pneumonia in adults. Methods: A comprehensive search was conducted in PubMed, Embase, Scopus, Web of Science, and LILACS following PRISMA guidelines. Two independent researchers reviewed eligible studies and assessed their quality using the QUADAS-2 and RoB 2.0 tools. The following questions guided the review: Q1. What sonographic signs are indicative of VAP? Q2. How can LUS be combined with other diagnostic tests? Q3. Can LUS reduce the time to diagnose VAP? Q4. Is LUS superior to standard diagnostic strategies? Main Results: Ten studies (n = 933 patients) with different designs were included. For Q1, the most relevant sonographic signs were subpleural consolidations (SP-CD) and dynamic air bronchograms (DAB). For Q2, studies suggested that combining LUS with microbiological tests or clinical scores increased diagnostic accuracy. Regarding Q3, LUS demonstrated potential to reduce diagnostic delays through sequential assessments, enabling early detection of lung changes. For Q4, limited evidence indicated that LUS may improve ventilation-free days compared to standard radiographic methods. Conclusion: SP-CD and DAB seem to be the most useful sonographic signs for diagnosing VAP. The association with laboratory findings and clinical scores appears to enhance accuracy when compared to LUS alone. Limited data suggest that LUS may anticipate diagnosis and improve outcomes.