Interstitial lung opacities in patients with severe COVID-19 pneumonia by bedside high-resolution ultrasound in association to CO2 retention.

Peschel, G; Jung, E M; Fisser, C; Putz, F J; Wertheimer, T; Sinner, B; Lunz, D; Jung, F; Müller, M

BACKGROUND Coronavirus disease 2019 (COVID-19) can cause acute respiratory distress Syndrome (ARDS). OBJECTIVE This single centre cross-section study aimed to grade the severity of pneumonia by bed-side lung ultrasound (LUS). METHODS A scoring system discriminates 5 levels of lung opacities: A-lines (0 points),≥3 B-Line (1 point), coalescent B-Lines (2 points), marked pleural disruptions (3 points), consolidations (4 points). LUS (convex 1-5 MHz probe) was performed at 6 defined regions for each hemithorax either in supine or prone position. A lung aeration score (LAS, maximum 4 points) was allocated for each patient by calculating the arithmetic mean of the examined lung areas. Score levels were correlated with ventilation parameters and laboratory markers. RESULTS LAS of 20 patients with ARDS reached from 2.58 to 3.83 and was highest in the lateral right lobe (Mean 3.67). Ferritin levels (Mean 1885μg/l; r = 0.467; p = 0.051) showed moderate correlation in spearman roh calculation. PaCO2 level (Mean 46.75 mmHg; r = 0.632; p = 0.005) correlated significantly with LAS, while duration of ventilation, Horovitz-Index, CRP, LDH and IL-6 did not. CONCUSIONS The proposed LAS describes severity of lung opacities in COVID-19 patients and correlates with CO2 retention in patients with ARDS.