Utility of Lung Ultrasonography for Early Diagnosis and Monitoring of Ventilator-associated Pneumonia in Mechanically Ventilated Patients: A Prospective Observational Study.

Background and aims: Ventilator-associated pneumonia (VAP) is a common intensive care unit (ICU) complication linked to increased morbidity and delayed diagnosis. Lung ultrasound (LUS) is a bedside, radiation-free tool with potential for early detection and monitoring. This study aimed to evaluate the diagnostic accuracy of LUS compared to expert panel adjudication and assess its role in monitoring treatment response. Patients and methods: In this prospective observational study conducted in a tertiary ICU, 206 adult patients ventilated for >48 hours underwent serial LUS starting 48 hours post-intubation. Lung ultrasound findings were compared with Clinical Pulmonary Infection Score (CPIS) and expert panel diagnosis (gold standard). Aeration scores were assessed; patients with a Δ score >2 between day 1 and day 5 of antibiotic therapy were considered responders. Results: Of the 206 patients, 73 developed VAP as confirmed by the expert panel. Lung ultrasound detected VAP significantly earlier than expert adjudication (median 150 vs 178.5 hours; p < 0.001), with 80.7% of cases diagnosed earlier by LUS. Lung ultrasound showed 91.78% sensitivity, 87.97% specificity, 80.7% positive predictive value (PPV), and 95.1% negative predictive value (NPV). Among 64 patients eligible for aeration score analysis, responders (n = 24) showed a non-significant trend toward higher 28-day survival (75 vs 52.5%, p = 0.074). Intensive care unit stay and ventilator duration were comparable between groups. Conclusion: Lung ultrasound demonstrates high diagnostic accuracy and enables earlier VAP detection compared to clinical scores. It effectively tracks disease progression and treatment response through serial aeration scores. Incorporating LUS into routine ICU care may enhance diagnostic timeliness and support individualized treatment strategies. Trial registration: The study was approved by the Institutional Ethics Committee of the IMS and SUM Hospital (Ref. no/ECR/627/Inst/OR/2014) and was registered with the Clinical Trials Registry of India (CTRI) under the registration number CTRI/2022/10/046326. How to cite this article: Roy C, Choudhury S, Chhotray P, Patra ESK, Panda S, Mishra SB. Utility of Lung Ultrasonography for Early Diagnosis and Monitoring of Ventilator-associated Pneumonia in Mechanically Ventilated Patients: A Prospective Observational Study. Indian J Crit Care Med 2025;29(9):753-759.