The Respiratory Strategies in COVID-19; CPAP, High-flow, and Standard Care (RECOVERY-RS) trial, which the Northern Care Alliance NHS Group (NCA) participated in, has demonstrated that treating hospitalised COVID-19 patients who have acute respiratory failure with continuous positive airway pressure (CPAP) reduces the need for invasive mechanical ventilation.
Over 150 patients were recruited from NCA hospitals to take part in this trial, the largest number from Fairfield General in Bury.
Preliminary data from the trial also suggests that the routine use of high flow nasal oxygenation (HFNO), which can consume large amounts of oxygen, should be reconsidered as it did not improve outcomes for COVID-19 patients compared with conventional oxygen therapy.
RECOVERY-RS, led by the University of Warwick and Queen’s University Belfast, is the world’s largest non-invasive respiratory support trial for COVID-19 - with over 1200 participants taking part across 48 UK hospitals. The multi-centre, adaptive, randomised controlled trial compared the use of CPAP (oxygen and positive pressure delivered via a tightly fitting mask), with HFNO (high pressure oxygen delivered up the nose), against standard care (standard oxygen therapy).
All three interventions are commonly used to treat COVID-19 patients before they are moved onto invasive ventilation in a critical care bed, but it was not known which, if any, resulted in better outcomes.
Results
Over 13 months, between April 2020 and May 2021, a total of 1,272 hospitalised COVID-19 patients with acute respiratory failure, aged over the age of 18, were recruited to the study and randomly allocated to receive one of three respiratory support interventions as part of their hospital care.
380 (29.9%) participants received CPAP; 417 (32.8%) participants received HFNO; and 475 (37.3%) received conventional oxygen therapy.
The primary outcomes assessed through the trial were whether the patient went on to require tracheal intubation (invasive mechanical ventilation) or died within 30-days of beginning treatment through the trial.
In the comparison of CPAP and conventional oxygen therapy, the likelihood of patients going on to require invasive mechanical ventilation or die within 30-days of treatment was significantly lower in those who were treated with CPAP, than those who received standard care. In the CPAP group, 137 of 377 participants (36.3%) either needed mechanical ventilation or died within 30 days, compared with 158 of 356 participants (44.4%) in the conventional oxygen therapy group.
There was no difference in primary outcomes between patients in the HFNO and conventional oxygen therapy groups. In the HFNO group, 184 of 414 participants (44.4%) went on to require mechanical ventilation or die, compared with 166 of 368 participants (45.1%) in the conventional oxygen therapy group.
Based on these results, 1 person would avoid needing invasive ventilation within intensive care units (ICU) for every 12 people treated with CPAP instead of standard oxygen therapy.
About RECOVERY-RS
Both CPAP and HFNO have been widely used worldwide in the management of COVID-19 throughout the pandemic for patients who need high levels of additional oxygen. If these treatments are not successful, patients need to be sedated and treated with a ventilator in intensive care. Although both CPAP and HFNO are commonly used in other lung conditions, prior to the RECOVERY-RS study, it was unknown how safe and effective they were for people with breathing difficulties arising from COVID-19.
The trial is led by Joint Chief Investigators Professor Gavin Perkins at the University of Warwick, and Professor Danny McAuley at Queen's University Belfast. It was funded and supported by the National Institute for Health Research (NIHR) as a prioritised urgent public health COVID-19 study.
RECOVERY-RS was one of the first COVID-19 studies to be classed as urgent public health research by the UK’s Chief Medical Officers in order to urgently identify strategies to reduce the need for invasive mechanical ventilation. Launched in April 2020 as COVID-19 hospitalisation began to soar, the NIHR Clinical Research Network provided prioritised research delivery support to rapidly set the study up at hospital sites across the UK and enroll participants. The NIHR’s research infrastructure, expertise and delivery support has been critical to the trial’s success.
The preliminary results of this evaluation of the data will be available as a pre-print on medRxiv on 5 August 2021 and will be submitted to a leading peer-reviewed medical journal. The results will be presented in detail at a free virtual Critical Care Reviews conference session (https://criticalcarereviews.com) on Thursday 5 August at 7.30pm.