CPAP delivered outside critical care during the second wave of COVID-19: outcomes from a UK respiratory surge unit

Abstract

BackgroundNHS England recommends non-invasive continuous positive airway pressure (CPAP) as a possible treatment for type 1 respiratory failure associated with COVID-19 pneumonitis, either to avoid intubation or as a ceiling of care. However, data assessing this strategy are sparse, especially for the use of CPAP as a ceiling of care, and particularly when delivered outside of a traditional critical care environment. We describe a cohort of patients from Liverpool, UK, who received CPAP on a dedicated respiratory surge unit at the start of the second wave of the COVID-19 pandemic in UK.MethodsRetrospective cohort analysis of consecutive patients receiving CPAP for the treatment of respiratory failure secondary to COVID-19 on the respiratory surge unit at the Royal Liverpool Hospital, Liverpool, UK from 21 September until 30 November 2020.Results88 patients were included in the analysis. 56/88 (64%) were deemed suitable for escalation to invasive mechanical ventilation (IMV) and received CPAP as a trial; 32/88 (36%) received CPAP as a ceiling of care. Median age was 63 years (IQR: 56–74) and 58/88 (66%) were men. Median SpO2/FiO2 immediately prior to CPAP initiation was 95 (92–152). Among patients for escalation to IMV, the median time on CPAP was 6 days (IQR 4–7) and survival at day 30 was 84% (47/56) with 14/56 (25%) escalated to IMV. Of those patients for whom CPAP was ceiling of care, the median duration of CPAP was 9 days (IQR 7–11) and 18/32 (56%) survived to day 30. Pulmonary barotrauma occurred in 9% of the cohort. There were no associations found on multivariant analysis that were associated with all-cause 30-day mortality.ConclusionsWith adequate planning and resource redistribution, CPAP may be delivered effectively outside of a traditional critical care setting for the treatment of respiratory failure due to COVID-19. Clinicians delivering CPAP to patients with COVID-19 pneumonitis should be alert to the dangers of pulmonary barotrauma. Among patients who are for escalation of care, the use of CPAP may avoid the need for IMV in some patients. Our data support the NHS England recommendation to consider CPAP as a ceiling of care.

Clinical update on COVID-19 for the emergency clinician: Airway and resuscitation

“…Other studies have found intubation may be avoided in 37–80% of patients with COVID-19 undergoing NIPPV [ [42] , [43] , [44] , [45] ]. A retrospective analysis of 88 patients receiving CPAP in the United Kingdom found a 56% survival rate, and a prospective observational study demonstrated 55% of cases successfully avoided intubation using helmet CPAP and were transferred to the general ward [ 46 , 47 ]. The SCCM and NIH guidelines do not include recommendations concerning the use of helmet NIPPV.…”

Non-invasive Respiratory Support in COVID-19: A Narrative Review

“…In the second wave, a UK study reported a 56% rate of survival in patients where CPAP was the ceiling of care. Interestingly, the mean time of CPAP use was 9 days ( 55 ). Similar results were reported by Aliberti et al with a mortality of 55% (36/65) in patients with DNI orders using helmet CPAP ( 56 ).…”

Non-invasive respiratory support in SARS-CoV-2 related acute respiratory distress syndrome: when is it most appropriate to start treatment?

“…Its optimal management is still much debated. The efficacy of Non-Invasive Respiratory Support (NRS) as Continuous Positive Airway Pressure (CPAP) and/or Non-Invasive mechanical Ventilation (NIV) in SARS-CoV-2-related hARF is controversial [ 1 – 3 ], even if several studies support CPAP use [ 4 – 10 ]. A trial of CPAP seems to significantly reduce mortality and oro-tracheal intubation (OTI) rates compared to conventional oxygen therapy in patients with SARS-CoV-2-related ARDS [ 10 ].…”

“…The recruitment of these alveoli through PEEP would significantly improve hypoxia and may prevent OTI. In addition mortality rates in patients with COVID-19-related ARDS undergoing OTI and invasive mechanical ventilation (IMV) appear extraordinarily high [ 4 , 9 , 11 – 16 ], up to 97% during first pandemic waves, also due to the associated risk of bacterial superinfection [ 13 ]. More recently Peñuelas et al [ 17 ] reports an overall 180-day survival rates of 59% in patients undergone IMV for COVID-19.…”