Response to Awake Prone Position in Nonintubated Individuals With COVID-19

Abstract

BACKGROUND:

Prone positioning is used for patients with ARDS undergoing invasive mechanical ventilation; its effectiveness in nonventilated awake patients is unclear. We aimed to evaluate the effectiveness of the prone maneuver in decreasing the risk of intubation and increasing the odds of favorable events.

METHODS:

We prospectively evaluated 66 subjects with COVID-19-related moderate ARDS who were admitted to the ICU; treated with high-flow nasal cannula, noninvasive ventilation, a reservoir mask, or a nasal cannula; and subjected to awake prone maneuvers from March 1, 2020–August 30, 2020. The following factors were recorded at ICU admission: age, sex, prior illness, simplified acute physiology score 3, body mass index, and changes in gas exchange after and before prone positioning. Subjects were divided into a group of responders and nonresponders according to a 20% increase in the $P_{a{O}_2}$ / $F_{I{O}_2}$ ratio before and after the maneuver. The need for intubation within 48 h of the start of the maneuver was also evaluated. We also analyzed the differences in mortality, ICU length of stay, hospital length of stay, and duration of mechanical ventilation. A generalized estimating equation model was applied to preprone and postprone means. To control for confounding factors, multivariate Poisson regression was applied.

RESULTS:

Forty-one subjects age 54.1 y ± 12.9 were enrolled. Responders showed increased $S_{p{O}_2}$ (P < .001), $P_{a{O}_2}$ (P < .001), and $P_{a{O}_2}$ / $F_{I{O}_2}$ ratios (P < .001) with the maneuver and reduced breathing frequency. Responders had shorter lengths of stay in the ICU (P < .001) and hospital (P < .003), lower intubation rates at 48 h (P < .012), fewer days of ventilation (P < .02), and lower mortality (P < .001). Subjects who responded to the maneuver had a 54% reduction in the risk of ventilation and prolonged stay in the ICU.

CONCLUSIONS:

Among the responders to prone positioning, there were fewer deaths, shorter duration of mechanical ventilation, shorter ICU length of stay, and shorter hospital length of stay.