The efficacy and tolerance of prone positioning in non-intubation patients with acute hypoxemic respiratory failure and ARDS: a meta-analysis.

BACKGROUND AND AIMS

The application of prone positioning with acute hypoxemic respiratory failure (AHRF) or acute respiratory distress syndrome (ARDS) in non-intubation patients is increasing gradually, applying prone positioning for more high-flow nasal oxygen therapy (HFNC) and non-invasive ventilation (NIV) patients. This meta-analysis evaluates the efficacy and tolerance of prone positioning combined with non-invasive respiratory support in patients with AHRF or ARDS.

METHODS

We searched randomized controlled trials (RCTs) (prospective or retrospective cohort studies, RCTs and case series) published in , and the from 1 January 2000 to 1 July 2020. We included studies that compared prone and supine positioning with non-invasive respiratory support in awake patients with AHRF or ARDS. The meta-analyses used random effects models. The methodological quality of the RCTs was evaluated using the Newcastle-Ottawa quality assessment scale.

RESULTS

A total of 16 studies fulfilled selection criteria and included 243 patients. The aggregated intubation rate and mortality rate were 33% [95% confidence interval (CI): 0.26-0.42,  = 25%], 4% (95% CI: 0.01-0.07,  = 0%), respectively, and the intolerance rate was 7% (95% CI: 0.01-0.12,  = 5%). Prone positioning increased PaO/FiO [mean difference (MD) = 47.89, 95% CI: 28.12-67.66;  < 0.00001,  = 67%] and SpO (MD = 4.58, 95% CI: 1.35-7.80,  = 0.005,  = 97%), whereas it reduced respiratory rate (MD = -5.01, 95% CI: -8.49 to -1.52,  = 0.005,  = 85%). Subgroup analyses demonstrated that the intubation rate of shorter duration prone (⩽5 h/day) and longer duration prone (>5 h/day) were 34% and 21%, respectively; and the mortality rate of shorter duration prone (⩽5 h/day) and longer duration prone (>5 h/day) were 6% and 0%, respectively. PaO/FiO and SpO were significantly improved in COVID-19 patients and non-COVID-19 patients.

CONCLUSION

Prone positioning could improve the oxygenation and reduce respiratory rate in both COVID-19 patients and non-COVID-19 patients with non-intubated AHRF or ARDS.