AimWe aim at characterising a large population of Coronavirus 19 (COVID-19) patients with moderate-to-severe hypoxemic acute respiratory failure (ARF) receiving CPAP outside intensive care unit (ICU), and ascertaining whether the duration of CPAP application increased the risk of mortality for patients requiring intubation.MethodsIn this retrospective, multicentre cohort study, we included COVID-19 adult patients, treated with CPAP outside ICU for hypoxemic ARF from March 1st to April 15th, 2020. We collected demographic and clinical data, including CPAP therapeutic goal, hospital length of stay (LOS), and 60-day in-hospital mortality.ResultsThe study includes 537 patients with a median age of 69 (IQR, 60–76) years. Males were 391 (73%). According to predefined CPAP therapeutic goal, 397 (74%) patients were included in full treatment subgroup, and 140 (26%) in the do-not intubate (DNI) subgroup. Median CPAP duration was 4 (IQR, 1–8) days, while hospital LOS 16 (IQR, 9–27) days. Sixty-day in-hospital mortality was overall 34% (95%CI, 0.304–0.384), and 21% (95%CI, 0.169–0.249) and 73% (95%CI, 0.648–0.787) for full treatment and DNI subgroups, respectively. In the full treatment subgroup, in-hospital mortality was 42% (95%CI, 0.345–0.488) for 180 (45%) CPAP failures requiring intubation, while 2% (95%CI, 0.008–0.035) for the remaining 217 (55%) patients who succeeded. Delaying intubation was associated with increased mortality [HR, 1.093 (95%CI, 1.010–1.184)].ConclusionsWe described a large population of COVID-19 patients treated with CPAP outside ICU. Intubation delay represents a risk factor for mortality. Further investigation is needed for early identification of CPAP failures.