Potential role of lung ultrasonography in outpatient follow-up of patients with COVID-19. A systematic review.

Introduction and aim: Currently, the usefulness of lung ultrasound in the follow-up of patients after hospital discharge for SARS-CoV-2 pneumonia is not well known. The main objective of this systematic review is to investigate the persistence of alterations in lung ultrasound of patients who have had COVID-19 pneumonia.

Methods: A systematic review has been carried out following the PRISMA regulations in the PubMed, EMBASE, Web of Science and Google Scholar database from January 2020 to May 2023 using the combination of MeSH terms: "lung ultrasound", "ultrasonography", "lung alterations", "persistence", "follow-up", "consequences", "hospital discharge", "COVID", "COVID-19", "SARS-CoV-2". Studies were selected that described alterations in the lung ultrasound of patients after having suffered from COVID-19 pneumonia. The JBI Critical Appraisal Tools were used to assess the risk of bias of the studies. No meta-analysis techniques were performed, the results being compared narratively.

Results: From two to six months after COVID-19 pneumonia, pulmonary ultrasound abnormalities appear frequently and are proportional to the intensity of the initial episode. The most frequent anomalies are irregularities in the pleural line, the presence of B lines and/or subpleural consolidations, predominantly in the basal regions of the thorax. These findings seem to correlate with those of the chest CT.

Conclusions: Lung ultrasound offers technical and economic advantages that should be considered for the study of patients after hospital discharge for COVID-19.