Integrated lung ultrasound score for early clinical decision-making in patients with COVID-19: results and implications

Abstract

Abstract Background and objectives Lung Ultrasound Score (LUS) identifies and monitors pneumonia by assigning increasing scores. However, it does not include parameters, such as inferior vena cava (IVC) diameter and index of collapse, diaphragmatic excursions and search for pleural and pericardial effusions. Therefore, we propose a new improved scoring system, termed “integrated” lung ultrasound score (i-LUS) which incorporates previously mentioned parameters that can help in prediction of disease severity and survival, choice of oxygenation mode/ventilation and assignment to subsequent areas of care in patients with COVID-19 pneumonia. Methods Upon admission at the sub-intensive section of the emergency medical department (SEMD), 143 consecutively examined COVID-19 patients underwent i-LUS together with all other routine analysis. A database for anamnestic information, laboratory data, gas analysis and i-LUS parameters was created and analyzed. Results Of 143 enrolled patients, 59.4% were male (mean age 71 years) and 40.6% female. (mean age 79 years: p = 0.005). Patients that survived at 1 month had i-LUS score of 16, which was lower than that of non-survivors (median 20; p = 0.005). Survivors had a higher PaO2/FiO2 (median 321.5) compared to non-survivors (median 229, p < 0.001). There was a correlation between i-LUS and PaO2/FiO2 ratio (rho:-0.4452; p < 0.001), PaO2/FiO2 and survival status (rho:-0.3452; p < 0.001), as well as i-LUS score and disease outcome (rho:0.24; p = 0.005). In non-survivors, the serum values of different significant COVID indicators were severely expressed. The i-LUS score was higher (median 20) in patients who required non-invasive ventilation (NIV) than in those treated only by oxygen therapy (median 15.42; p = 0.003). The odds ratio for death outcome was 1.08 (confidence interval 1.02–1.15) for each point increased. At 1-month follow-up, 65 patients (45.5%) died and 78 (54.5%) survived. Patients admitted to the high critical ward had higher i-LUS score than those admitted to the low critical one (p < 0.003). Conclusions i-LUS could be used as a helpful clinical tool for early decision-making in patients with COVID-19 pneumonia.

Keywords

• COVID-19
• SARS-CoV-2
• Lung Ultrasound Score (LUS)
• Integrated Lung Ultrasound Score (i-LUS)
• Emergency Department