The investigators will retrospectively analyse medical records of patients with confirmed Covid-19 respiratory failure who received continuous positive airway pressure (CPAP) via facemask, as per clinician decision, in the High Dependency Unit (HDU) or Intensive Care Unit (ICU) of University Hospital Crosshouse between 1st March 2020 and 30th April 2021. By collecting baseline demographics and physiological data (including APACHE II and clinical frailty score) and calculating the HACOR score at initiation of CPAP, then at 1hr, 6hrs, 12hrs, 24hrs and 48hrs after initiating CPAP the investigators aim to validate use of the HACOR score in determining efficacy of NIV in Covid-19 respiratory failure. The investigators will also collect other variables (CRP and lymphocytes, lactate, mean arterial pressure, temperature) to determine if these factors have utility in predicting efficacy of NIV in Covid-19 respiratory failure.
A retrospective, single centre observational study to validate use of the HACOR score (Duan et al, 2017) in determining efficacy of non-invasive ventilation in Covid-19 respiratory failure.