Utility of Continuous Positive Airway Pressure (CPAP) in COVID pneumonitis patients not suitable for mechanical ventilation

Abstract

Hospitals throughout the country have utilised different strategies in the management of COVID pneumonitis. Our hospital established a Respiratory High Care Unit (RHCU) to provide CPAP to patients deteriorating despite Standard Oxygen Therapy (SOT). Patients were considered to be either for full escalation (intubation and mechanical ventilation) or to have CPAP as a ceiling of care. Our aim was to assess CPAP success in those not eligible for mechanical ventilation. We retrospectively analysed patients admitted to RHCU who had a CPAP ceiling of care. Between 1st June 2020 and 31st March 2021, 156 patients were admitted, with 144 notes available for analysis. Patients were transferred to RHCU following review by respiratory consultant and met Trust criteria for CPAP. 75 patients (52%) had a ceiling of care of CPAP. 8 patients were excluded. Average age was 75.1 years. Mean Clinical Frailty Score (CFS) was 3.6. 70% were male. 97% were admitted with FiO2 ≥40%. Mortality in patients with CPAP as ceiling of care was 79%. Patients that survived had a mean age was 74.6 years, a mean CFS of 3.1 and a pO₂ on admission of 7.8kPa, as compared to a mean age of 75.2 years, a mean CFS of 3.7 and pO₂ on admission of 7.7kPa in those that died. Demographics between the two cohorts of patients were similar, making it difficult to predict who would survive with CPAP therapy. 21% of patients not suitable for mechanical ventilation survived with CPAP. In other centres, these patients may have only been eligible for SOT alone. The data suggests that offering CPAP may increase survival in patients that would not be suitable for mechanical ventilation.