Anticipated response to prone position assessed with lung ultrasound.

Acute respiratory distress syndrome (ARDS) presents a challenge for clinicians due to its high morbidity and mortality. Prone position (PP) has been used as a therapeutic strategy in ARDS patients, demonstrating benefits in respiratory mechanics and gas exchange. In SARSCoV-2-related ARDS (C-ARDS), 80% of patients require PP to alleviate refractory hypoxemia. Lung ultrasound (LUS) has proven useful for evaluating lung reaeration, guiding PEEP titration, and differentiating ARDS phenotypes. The LUS score is a validated tool that correlates well with CT and mechanical parameters. In this case, a 60-year-old patient with C-ARDS, who experienced a drop in PaO2/ FiO2 from 170 to 113, was placed in PP. Using LUS, a shift in aeration is associated with improved oxygenation, despite no significant changes in respiratory mechanics. This case highlights the usefulness of LUS in assessing PP response and the need for further studies to correlate changes in aeration with improvements in oxygenation and dead space, which could help identify patients who are responders to the maneuver.