Acute oxygen therapy: a cross-sectional study of prescribing practices at an English Hospital immediately before COVID-19 pandemic

Background: Approximately 14% of UK hospital in-patients receive supplemental oxygen therapy, but only 57% have valid prescriptions. Oxygen must be optimally prescribed to ensure maximal therapeutic response whilst minimising adverse outcomes (including fatality). This study investigates prescription compliance.

Methods: All adults admitted to medical wards (18th February - 3rd March 2020) were included. Analyses present proportions, descriptive statistics and hypothesis testing. Ethical approval was not required for this audit.

Results: Of the 636 patients admitted, 66 (10%) were receiving oxygen therapy. Ages ranged from 34-100 years with 36 (54.5%) males and 30 (45.5%) females. The prescription was not documented in the oxygen section of the drug chart (n=37, 56.1%, p=0.389), nor did it have the physicians signature (n=40, 60.6%, p=0.110) nor date (n=46, 69.7%, p=0.002). Thirteen chronic obstructive pulmonary disease (COPD) patients (19.7%) were at risk of hypercapnic failure (p=1.582x10^-6). Target oxygen saturation (SpO2) range had been documented for 30 (45.5%) patients. A target SpO2 range of 88-92% was documented for 9 patients (13.6%), a 94-98% range documented for 11 patients (16.7%). All patients had an invalid prescription.

Conclusion: We present real-world practice in naturalistic settings, immediately before pandemic-lockdown. Enhanced compliance is advocated to reduce risks of harm and mortality.

Keywords: Chronic Obstructive; Dyspnea; Hypercapnia; Hypoxia; Iatrogenic Disease; Inpatients; Oximetry; Oxygen; Oxygen Inhalation Therapy; Pulmonary Disease.