Fig. 4

Use of lung ultrasound to monitor lung aeration and guide ventilatory management in 2 COVID-19 patients. a COVID-19 patient on day 2 after intubation and ICU admission, initially with PEEP 12 cmH₂O: diffuse bilateral B-pattern with crowded, coalescent B-lines (“white lung appearance”) is visible, consistent with a sonographic interstitial syndrome and severe loss of aeration/increase of extravascular lung water. Based on these findings and on respiratory mechanics, a stepwise recruitment maneuver with a final PEEP set at 15 cmH₂0 was performed, with improvement in gas exchange. b A different COVID-19 patient on day 4; PEEP set at 14 cmH₂O: in comparison with previous patient, less B-lines are visible in ventral scans, with asymmetric distribution (more on the left scan); dorsal areas show lung consolidations, larger on the right side, with air bronchograms (dynamic at live scan). A pronation trial was successful, yielding immediate improvement in gas exchange and subsequent re-aeration of dorsal areas. (Ventral scans are taken with a linear, high frequency probe, dorsal ones with a phased array low-frequency one)