Screening COVID-19 by Point-of-care Lung Ultrasound: a Validation Study (SCOUT)

COVID-19 is a rapidly spreading and very contagious disease caused by a novel coronavirus that can lead to respiratory insufficiency. In many patients, the chest radiograph at first presentation be normal, and early low-dose CT-scan is advocated to diagnose viral pneumonia. Lung ultrasound (LUS) has similar diagnostic properties as CT for diagnosing pneumonia. However, it has the advantage that it can be performed at point-of-care, minimizing the need to transfer the patient, reducing the number of health care personnel and equipment that come in contact with the patient and thus potentially decrease the risk of spreading the infection. This study has the objective to examine the accuracy of lung ultrasound in patients with proven COVID-19 pneumonia.

Patients with the diagnosis of COVID-19 pneumonia will undergo a lung ultrasound, by two observers each. The findings will be compared with findings on chest x-ray and/or CT thorax. Accuracy and inter-observer variability will be calculated.

The lung ultrasound examination consists of two-sided scanning of the anterior and lateral chest wall and is performed with patients in supine or near-to-supine position.

The diagnostic accuracy of lung ultrasound is more than 90% compared to low-dose CT or chest X-ray for the detection of viral pneumonia in patients with COVID-19 infection.

The interobserver variability by lung ultrasound between the 2 observers for the diagnosis of interstitial syndrome by lung ultrasound is > 0.6 measured by the Kappa score

Inclusion Criteria: high probability CT thorax or chest X-ray for viral pneumonia within five days of the day of inclusion positive COVID-19 nasopharyngeal swab within 10 days of inclusion 18 years or older Oxygen saturation of < 93% in ambient air Signed written informed consent Exclusion Criteria: Contra-indication for lung ultrasound Other causes of hypoxia or of pulmonary infiltrates on CT thorax or chest X-ray

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