Abstract / Summary
Abstract Introduction Awake prone positioning (APP) has been widely used in patients with COVID-19-related acute respiratory distress syndrome (ARDS), but its effectiveness may vary depending on the oxygenation interface. This study aimed to compare the response to APP according to different oxygenation interfaces and to identify predictors of response. Methods We conducted a prospective observational study including adult patients admitted to the intensive care unit for severe to critical COVID-19, from March to May 2021. APP sessions of at least 30 min were performed within the first 24 h using conventional oxygen therapy (COT), high-flow nasal oxygen (HFNO), and noninvasive ventilation (NIV), applied sequentially when tolerated. Arterial blood gases were measured before and 20 min after each session. Response was defined as an increase of ≥ 20% in the PaO₂/FiO₂ ratio. Results Fifty-six patients were included. Response rates differed across interfaces: 25.5% under COT, 34.4% under HFNO, and 43.9% under NIV. Responders under COT and HFNO had lower intubation rates ( p = 0.03 and p = 0.01, respectively), and responders under HFNO had shorter hospital stays ( p = 0.018). Mortality was higher among non-responders for all interfaces except NIV ( p = 0.6). Higher body mass index (BMI) was associated with response under COT and HFNO, with ROC analysis identifying a predictive cutoff between 27.3 and 28.3 kg/m². Conclusions The response to APP differs according to the oxygenation interface. APP response may be associated with improved clinical outcomes, particularly under COT and HFNO. Higher BMI appears to predict a favorable response. These findings should be interpreted cautiously given the observational design and sequential application of interfaces.