CPAP reduces tracheal intubation, mortality in adults with COVID-19–related acute hypoxemic respiratory failure

The use of continuous positive airway pressure (CPAP) significantly reduces the risk of tracheal intubation and mortality among hospitalized patients with COVID-19–related acute hypoxemic respiratory failure, according to the RECOVERY-RS* trial.

This adaptive, parallel-group trial analysed 1,273 adults (mean age 57.4 years, 66.3 percent male) who were hospitalized due to COVID-19 with related acute hypoxemic respiratory failure at 48 acute hospitals in the UK and Jersey between April 6, 2020 and May 3, 2021. Participants were randomized to receive CPAP (n=380), high-flow nasal oxygen (HFNO; n=418), or conventional oxygen therapy (n=475). [JAMA 2022;doi:10.1001/jama.2022.0028]

The composite outcome of the need for tracheal intubation or number of deaths within 30 days occurred at a significantly lower rate in the CPAP group than the conventional oxygen therapy group (36.3 percent vs 44.4 percent, absolute difference, -8.0 percent; p=0.03).

The need for intensive care unit (ICU) admission was also reduced in the CPAP vs conventional oxygen therapy group (55.4 percent vs 62.9 percent, absolute difference, -7.0 percent).

However, there was no significant difference in the composite outcome of tracheal intubation or number of deaths within 30 days between the HFNO and conventional oxygen therapy groups (44.3 percent vs 45.1 percent, absolute difference, -1.0 percent; p=0.83).

“[This could have been due to] the trial [being] underpowered to detect small but clinically important treatment effects,” the researchers noted.

With regard to individual components of the composite endpoints, the CPAP group showed a lower incidence of tracheal intubation than those in the conventional oxygen therapy group (33.4 percent vs 41.3 percent), though mortality incidence did not differ between the two groups (16.7 percent vs 19.2 percent).

A post hoc analysis showed that there was a significantly lower risk of the composite outcome of tracheal intubation or mortality among those on CPAP vs those on HFNO (34.6 percent vs 44.3 percent, absolute difference, -10.0 percent; p=0.02).

Adverse events occurred more frequently in the CPAP group vs the HFNO and conventional oxygen therapy groups (34.2, 20.6, and 13.9 percent, respectively).

The trial was stopped early due to a rapid decrease in COVID-19 cases in the UK, and treatment crossover occurred in 15.3, 11.5, and 23.6 percent of patients in the CPAP, HFNO, and conventional oxygen therapy groups, respectively. “This is a common challenge in trials of noninvasive respiratory strategies and reduces the observed effect size of a clinically effective treatment,” the researchers highlighted.

“[Nevertheless,] among patients with acute hypoxemic respiratory failure due to COVID-19, an initial strategy of CPAP significantly reduced the risk of tracheal intubation or mortality compared with conventional oxygen therapy, but there was no significant difference between an initial strategy of HFNO compared with conventional oxygen therapy,” they concluded.

“[E]arly study termination and crossover among the groups should be considered when interpreting the findings,” they noted.

*RECOVERY-RS: Respiratory Strategies in patients with coronavirus COVID-19 – CPAP, high-flow nasal oxygen, and standard care