Awake prone positioning lowers risk for intubation, not mortality with COVID-19 hypoxemia

Awake prone positioning lowered the risk for endotracheal intubation but not for mortality compared with usual care among patients with hypoxemic respiratory failure from COVID-19, according to a study published in The BMJ.

Jason C. Weatherald

“The results of this meta-analysis do suggest that using awake prone positioning and supporting patients to do so will likely prevent intubations and is safe,” Jason C. Weatherald, MD, MSc, FRCPC, associate professor of medicine and pulmonologist at University of Alberta Hospital in Edmonton, Canada, told Healio. “However, since patients in many trials had difficulty adhering to proning, clinicians need to develop strategies to encourage and support patients to do it, despite how unwell they may feel from their illness.”

In a systematic review and meta-analysis, Weatherald and colleagues analyzed 17 randomized trials that included a total of 2,931 nonintubated adults with COVID-19-related hypoxemic respiratory failure and that compared the safety and efficacy of awake prone positioning with usual care.

Using random effects and Bayesian meta-analyses, the researchers assessed endotracheal intubation in patients as the study’s primary endpoint, and they looked at mortality, ventilator-free days, length of stay in the ICU and hospital, change in oxygenation and respiratory rate, escalation of oxygen modality and adverse events as secondary outcomes.

Of the trials included, researchers observed different levels of bias: 12 had low risk of bias, three had some concerns and two had high risk of bias.

When assessing the risk for endotracheal intubation, researchers found a decreased risk in a pooled analysis of 14 trials with high certainty evidence linked to awake prone positioning, with a crude average of 24.2% vs. 29.8% in the usual care group (RR = 0.83; 95% CI, 0.73-0.94).

Researchers wrote that this finding also means awake prone positioning yielded 55 (95% CI, –87 to –19) fewer intubations per 1,000 patients than usual care.

However, in subgroup analysis of 10 trials, researchers found that median daily length of time using awake prone positioning and the risk for endotracheal intubation were not significantly related.

“Although trials with longer duration of prone positioning adherence seemed to have greater reductions in intubation, there was no clear association between duration of proning at the trial level and the magnitude of reduction in intubation in several different analyses,” Weatherald told Healio. “This seems counterintuitive though perhaps these analyses are not adequately powered and this question would be better addressed using an individual patient data-level meta-analysis rather than a trial-level meta-analysis.”

In terms of secondary outcomes, there was high certainty evidence from 13 trials that there was no significant difference between awake prone positioning and usual care when evaluating mortality (15.6% vs. 17.2%; RR = 0.9; 95% CI, 0.76-1.07).

Further, researchers observed no significant benefit based on low- and moderate-certainty evidence for awake prone positioning regarding ventilator-free days (mean difference, 0.97 days; 95% CI, 0.5 to 3.4), ICU length of stay (mean difference, 2.1 days; 95% CI, 4.5 to 0.4), hospital length of stay (mean difference, 0.09 days; 95% CI, 0.69 to 0.51) or escalation of oxygen modality (21.4% vs. 23%; RR = 1.04; 95% CI, 0.74-1.44).

“This suggests that the modest benefit of avoiding intubations did not translate to more lives saved or quicker discharge from hospital,” Weatherald told Healio.

Additionally, Bayesian meta-analysis results using a noninformative prior were similar to the above findings with awake prone positioning demonstrating a high likelihood of benefit for endotracheal intubation (mean RR = 0.83; 95% credible interval [Crl], 0.7-0.97) but not for mortality (mean RR = 0.9; 95% Crl, 0.73-1.13), according to researchers.

Researchers reported infrequent awake prone positioning adverse events, concluding that it is "generally safe.”

“Future studies need to determine if longer durations of awake prone positioning truly are better, and whether awake prone positioning is useful in non-COVID-19 hypoxemic respiratory failure,” Weatherald told Healio. “Studies are also needed to establish effective methods for implementing this intervention and to determine which strategies maximize patients' adherence.”

For more information:

Jason C. Weatherald, MD, MSc, FRCPC, can be reached at weathera@ualberta.ca.

Reference:

Lying prone reduces need for breathing tube in COVID-19 patients. https://www.bmj.com/company/newsroom/lying-prone-reduces-need-for-breathing-tube-in-covid-19-patients/. Published Dec. 7, 2022. Accessed Dec. 13, 2022.