Effect of high-flow nasal cannula oxygen therapy with awake prone position ventilation vs. supine position ventilation in patients with severe pneumonia: a quasi-experimental study

<bold>Background:</bold> This study aims to evaluate the effect of high-flow nasal cannula (HFNC) oxygen therapy combined with awake prone position ventilation (APPV) vs. supine position ventilation (SPV) in patients with severe pneumonia. <bold>Methods:</bold> This is a quasi-experimental study enrolled patients diagnosed with severe pneumonia from the Department of Respiratory and Critical Care Medicine of the Fourth People's Hospital of Zigong City between November 2021 and January 2023. The primary endpoint was the treatment effectiveness. <bold>Results:</bold> A total of 120 patients with severe pneumonia were enrolled, evenly divided with 60 patients receiving HFNC+APPV and the other 60 receiving HFNC+SPV. The HFNC+APPV group demonstrated higher efficacy (90.0% vs. 76.7%, P=0.040) and shorter length of hospital stay (11.00 (9.00,13.00) vs. 12.00 (10.00,16.00), P=0.004) compared to the HFNC+SPV group. The generalized estimation equation showed that the OI index at 12h, 24h, 48h and 72h was significantly higher than that at 0h (p<0.001), however, there was no significant difference in the change between HFNC+APPV group and HFNC+SPV group (P=0.604). There was no significant difference in the rate of adverse events between the HFNC+APPV group and HFNC+SPV group (P>0.05). <bold>Conclusion:</bold> This study found that the combined application of HFNC and APPV may increase the efficacy of HFNC, and reduce the duration of hospitalization in patients with severe pneumonia, which provides reliable theoretical guidance for the choice of ventilation treatment position for patients with severe pneumonia.