Prognostic Value of Point of Care Cardiac and Lung Ultrasound in COVID-19

Background and scientific rationale:

During the COVID-19 pandemic, health care systems around the world are overwhelmed.

Surge of patients requiring hospital admission have led to shortages of ICU beds and mechanical ventilators. As an emerging clinical entity, little is known about the precise pathophysiologic mechanisms of COVID-19. Recent observational data and clinical experience has suggested that there could be different phenotypes of patients with COVID-19 which could explain the wide range of clinical presentations, response to therapies and outcomes.

Point of care cardiac and lung ultrasound (CLUS) has been proposed as a tool with potential to assist diagnostic evaluation and management of COVID-19 patients in the emergency department (ED) and intensive care unit (ICU) settings. Point of care CLUS is routinely used as part of the clinical evaluation of patients with dyspnea, hypoxemia, chest pain and shock in the ED and ICU. Patients with COVID-19 commonly present to the ED with these symptoms and therefore CLUS is being commonly used in patients with suspected or confirmed diagnosis of COVID-19.

Small observational studies have described several lung ultrasound (LUS) findings in patients with COVID-19. These findings include; pleural irregularity ("thickening"), subpleural consolidations, air bronchogram, isolated B-lines, fused B-lines and pleural effusions. Other observational studies have described the presence of acute myocardial abnormalities in patients with COVID-19 seen in echocardiography, including left and right ventricular systolic dysfunction.

Multiple studies have described and validated the finding of B-lines in LUS as a non-invasive marker of extravascular lung water. B-lines in LUS correlate with pulmonary capillary wedge pressures, NT-proBNP and E/e' and has been validated as a reliable prognostic factor in patients with decompensated heart failure. B-lines are also found in other pulmonary processes including viral pneumonia, ARDS, pulmonary contusions and post radiation changes. Observational studies involving COVID-19 patients have shown the presence of isolated and fused or continuous B-lines in the pneumonia associated with this infection. We hypothesize that the presence of B-lines in LUS may be marker of severity, and that alone or in concert with other clinical or laboratory variables, could help predict the clinical course and prognosis of COVID-19 patients.

Knowledge gaps

• Does point of care cardiopulmonary ultrasound findings alone, or combined with other clinical and/or laboratory variables, predict clinical outcomes of patients with COVID-19?
• Can different lung ultrasound finding patterns correlate with clinical severity or outcomes?

Specific aims

• To characterize various clinical and CLUS findings and describe their relationship with clinical course of patients with COVID-19 in ED and ICU.
• Using clinical, laboratory and ultrasound data to describe, develop and validate a prediction tool that can accurately predict (1) need of invasive mechanical ventilation (IVM) and (2) acute respiratory failure

Inclusion criteria

• COVID-19 positive or suspected positive
• Received a cardiopulmonary ultrasound scan

Exclusion criteria

• Did not receive a scan
• Not COVID-19 positive