Background: The effect of prone positioning (PP) on respiratory mechanics remains uncertain in patients with severe acute respiratory distress syndrome (ARDS) requiring venovenous extracorporeal membrane oxygenation (VV-ECMO). Methods: We prospectively analyzed the effects of PP on respiratory mechanics from continuous data with over a thousand time points during 16-h PP sessions in patients with COVID-19 and ARDS under VV-ECMO conditions. The evolution of respiratory mechanical and oxygenation parameters during the PP sessions was evaluated by dividing each PP session into four time quartiles: first quartile: 0–4 h, second quartile: 4–8 h, third quartile: 8–12 h, and fourth quartile: 12–16 h. Results: Overall, 38 PP sessions were performed in 10 patients, with 3 [2–5] PP sessions per patient. Seven (70%) patients were responders to at least one PP session. PP significantly increased the PaO 2 /FiO 2 ratio by 14 ± 21% and compliance by 8 ± 15%, and significantly decreased the oxygenation index by 13 ± 18% and driving pressure by 8 ± 12%. The effects of PP on respiratory mechanics but not on oxygenation persisted after supine repositioning. PP-induced changes in different respiratory mechanical parameters and oxygenation started as early as the first-time quartile, without any difference in PP-induced changes among the different time quartiles. PP-induced changes in driving pressure (−14 ± 14 vs. −6 ± 10%, p = 0.04) and mechanical power (−11 ± 13 vs. −0.1 ± 12%, p = 0.02) were significantly higher in responders (increase in PaO 2 /FiO 2 ratio > 20%) than in non-responder patients. Conclusions: In patients with COVID-19 and severe ARDS, PP under VV-ECMO conditions improved the respiratory mechanical and oxygenation parameters, and the effects of PP on respiratory mechanics persisted after supine repositioning.
【저자키워드】 acute respiratory distress syndrome (ARDS), alveolar recruitment, venovenous extracorporeal membrane oxygenation, prone positioning (PP), positive end-expiratory pressure (PEEP), 【초록키워드】 Evolution, ARDS, VV-ECMO, extracorporeal membrane oxygenation, Patient, Compliance, Responder, change, parameters, patients, acute respiratory distress, Oxygenation, prone positioning, Respiratory mechanics, Mechanical power, severe ARDS, syndrome, oxygenation index, Continuous data, driving, quartiles, parameter, quartile, Effect, significantly increased, analyzed, performed, significantly, evaluated, condition, changes in, increase in, significantly higher, conditions, PaO, patients with COVID-19, remains uncertain, 【제목키워드】 COVID-19, prone, positioning, respiratory, Extracorporeal, Mechanics, Effect, Ill,