Usefulness of Lung Ultrasound for early detection of Hospital-Acquired Pneumonia in Patients on Veno-Arterial Extra Corporeal Membrane Oxygenation.

Abstract BACKGROUND: Hospital-Acquired Pneumonia (HAP) is the most common and severe complication in patients treated with veno-arterial extracorporeal membrane oxygenation (ECMO). HAP early detection is challenging but crucial for improving clinical outcomes. We conduct an observational study to assess whether Lung Ultrasound (LUS) improves detection of HAP in in patients treated with veno-arterial ECMO.METHODS: We conducted a single-center, prospective, observational study including adult patients receiving veno-arterial extracorporeal membrane oxygenation assistance that presented acute respiratory failure. Bedside LUS and chest radiography were performed at the time of inclusion when HAP was suspected. Then the patients were independently assessed for HAP including microbiological evidence. The sonographic features of HAP on veno-arterial ECMO were determined. We then compared the performance of the lung ultrasound simplified clinical pulmonary score (LUS-sCPIS), including bio-clinical data and the Doppler detection of intrapulmonary shunt, to the sCPIS, including bio-clinical and chest radiological data for detection of HAP. RESULTS: We included 70 patients, of which 44 (63%) were independently diagnosed with hospital-acquired pneumonia. LUS examination revealed that Doppler intrapulmonary shunt (P=0.0000043) and dynamic air bronchogram (P=0.00024) were the most frequent hospital-acquired pneumonia-related signs. The LUS-sCPIS (Area under the curve = 0.77) yielded significantly better results than the sCPIS (Area under the curve = 0.65; P = 0.004), while leukocyte count, temperature and chest radiology were not discriminating for the hospital-acquired pneumonia diagnosis.CONCLUSION: The diagnosis of hospital-acquired pneumonia is a daily challenge for the clinician managing patients on veno-arterial ECMO . Lung ultrasound is more powerful than chest radiography and can be a valuable aid as initial imaging modality for the diagnosis of pneumonia. Intrapulmonary shunt detected using color Doppler and dynamic air bronchogram appear to be particularly discriminating for the diagnosis of hospital-acquired pneumonia.CLINICAL TRIAL REGSITRATION: NA