Applicability of lung ultrasound in COVID-19 diagnosis and evaluation of the disease progression: A systematic review

 

Abstract

Introduction

The COVID-19 pandemic originated in China and within about 4 months affected individuals all over the world. One of the limitations to the management of the COVID-19 is the diagnostic imaging to evaluate lung impairment and the patients’ clinical evolution, mainly, in more severe cases that require admission into the intensive care unit. Among image examinations, lung ultrasound (LU) might be a useful tool to employ in the treatment of such patients.

Methods

A survey was carried out on PubMed to locate studies using the descriptors: ((Lung ultrasound OR ultrasound OR lung ultrasonography OR lung US) AND (coronavirus disease-19 OR coronavirus disease OR corona virus OR COVID-19 OR COVID19 OR SARS-CoV-2)). The period covered by the search was November 2019 to October 2020 and the papers selected reported LU in COVID-19.

Results

Forty-three studies were selected to produce this systematic review. The main LU findings referred to the presence of focal, multifocal and/or confluent B lines and the presence of pleural irregularities.

Conclusions

The use of LU in the evaluation of patients with COVID-19 should be encouraged due to its intrinsic characteristics; a low cost, radiation free, practical method, with easy to sanitize equipment, which facilitates structural evaluation of lung damage caused by SARS-CoV-2. With the increase in the number of studies and the use of ultrasound scans, LU has been shown as a useful tool to evaluate progression, therapeutic response and follow-up of pulmonary disease in the patients with COVID-19.

Keywords

Image examination 

Lung disease 

Lung ultrasound 

SARS-CoV-2

Highlights

LU findings presented correlation with HRCT images.

LU can be used in respiratory system propaedeutics as an alternative to the “stethoscope use”. Special clothing and individual protection equipment are indispensable, since the manipulation of the stethoscope in pulmonary evaluation might create contamination risks for the health professionals and patients.

COVID-19 normally induces a bilateral and diffuse interstitial pneumonia with asymmetric lesions and uneven distribution, mainly involving the lung periphery, which makes it particularly suitable for investigation using LU.60

Studies have identified potential correlation between the LU patterns and the patients’ clinical outcome. One of the assays in this study reported that each pulmonary area could be in a different stage of the disease, therefore, the global evaluation of the lungs is fundamental.69

The POCUS allows for hemodynamic, cardiac and vascular evaluations (thromboembolic phenomena — deep venous thrombosis).

LU should be associated to the multisystem point-of-care exam, since the SARS-CoV-2 infection might be linked to myocarditis and a high incidence of thromboembolic events. Thus, multiorgan ultrasound evaluation in early treatment is useful to screening these complications at the bedside.

Perspectives

More studies on LU application in the pediatric population are necessary.

LU in COVID-19 score standardization.

Improvement of reading/automatic identification of B line software, as reported in this study is still needed.74

The advancement of the remote robotic ultrasound scanning technology assisted by the 5G network in real time by the use of big data, cloud storage and artificial intelligence must be improved.73