Non-invasive Oxygenation Strategies for Reducing the Incidence of Pneumonia in Adult Patients with Acute Hypoxemic Respiratory Failure: A Systematic Review and Network Meta-analysis

Background: In the current guidelines, the usage of non-invasive oxygenation strategies, such as non-invasive positive pressure ventilation (NPPV) and high-flow nasal oxygen (HFNO), for acute hypoxemic respiratory failure (AHRF) are unable to provide conclusive recommendations. We aimed to identify the most optimum respiratory management strategy reducing pneumonia in patients with AHRF. Methods: We searched the four databases for eligible trials. Studies including adults with AHRF and randomized controlled trials comparing two different respiratory management methods (NPPV, HFNO, standard oxygen therapy [SOT], or invasive mechanical ventilation [IMV]) were reviewed. The primary outcome was the incidence of pneumonia. A network meta-analysis was performed a frequentist approach with a multivariate random-effects meta-analysis. Results: We identified 14,263 unique articles, reviewed 126 full-text articles, and finally included 13 studies. Using IMV as the reference, NPPV (risk ratio [RR], 0.23; 95% confidence interval [CI], 0.11–0.51; moderate certainty) and HFNO (RR, 0.24; 95% CI, 0.09–0.64; moderate certainty) were significantly associated with a lower incidence of pneumonia. Compared with SOT, NPPV (RR, 0.55; 95% CI, 0.35–0.84; moderate certainty) but not HFNO (RR, 0.55; 95% CI 0.27–1.13; low certainty) was significantly associated with a lower incidence of pneumonia. The probability of being the best in reducing the incidence of pneumonia among all interventions was higher for NPPV and HFNO, followed by SOT, whereas IMV was the worst. Conclusions: Our findings imply that NPPV and HFNO may be the most effective strategies for primary respiratory management in adults with AHRF to reduce pneumonia.