CPAP reduced intubation, death in patients with COVID-19-related acute respiratory failure
CPAP reduced tracheal intubation and death within 30 days, compared with conventional oxygen therapy, in adults hospitalized with acute respiratory failure due to COVID-19, according to a new study.
“Early on in the pandemic, there was global concern about whether intensive care units would meet the surge capacity and would have the capacity to meet the surge demand in patients requiring invasive mechanical ventilation. That drove an urgent need to determine the clinical effectiveness of noninvasive respiratory support strategies,” Bronwen Connolly, PhD, senior lecturer in critical care, Queen’s University Belfast, Northern Ireland, said during a presentation at the virtual European Respiratory Society International Congress.
The Recovery Respiratory Support trial was an adaptive three-arm, open-label, randomized controlled trial that included 1,272 adults with suspected or confirmed COVID-19 infection and acute respiratory failure. The researchers aimed to evaluate whether CPAP and high-flow nasal oxygen were clinically effective in this patient population compared with conventional oxygen therapy.
Patients at 75 hospitals in the United Kingdom were randomly assigned to CPAP (n = 380), high-flow nasal oxygen (n = 417) or conventional oxygen therapy (n = 475).
The primary outcome was a composite of tracheal intubation or death within 30 days.
The trial was conducted from April 2020 to May 2021 and ended due to a decline in COVID-19 cases and hospitalizations in the U.K., according to Connolly.
Tracheal intubation or death within 30 days occurred in fewer patients assigned CPAP compared with conventional oxygen therapy (OR = 0.72; 95% CI, 0.53-0.96; P = .03). However, there was no difference in the primary outcome between those assigned high-flow nasal oxygen compared with conventional oxygen therapy (OR = 0.97; 95% CI, 0.73-1.29; P = .85), Connolly said.
“That decrease in [the] primary outcome in the CPAP group is driven by a decrease in the incidence of tracheal intubation,” Connolly said.
There was no difference in mortality within 30 days with CPAP vs. conventional oxygen therapy (OR = 0.84; 95% CI, 0.58-1.23) or with high-flow nasal oxygen vs. conventional oxygen therapy (OR = 0.93; 95% CI, 0.65-1.32).
Fewer patients in the CPAP arm required critical care ICU admission (54.1% vs. 61.5%; OR = 0.74; 95% CI, 0.55-0.99) and time to tracheal intubation was longer (median, 2.2 days vs. 1 day; OR = 0.74; 95% CI, 0.58-0.94). There were no differences in the other secondary outcomes.
Safety events centered on episodes of hemodynamic instability and occurred primarily in the CPAP arm compared with patients in the high-flow nasal oxygen or conventional oxygen therapy arms (P < .001), Connolly said.
Connolly noted several limitations of this study, including not achieving the sample size prior to study conclusion, a lack of blinding and subjective decisions to intubate at the clinical team’s discretion. Moreover, Connolly also said these results are not generalizable to those in whom escalation to invasive ventilation is not feasible.