Controlled oxygen therapy at emergency department presentation increases the likelihood of achieving target oxygen saturations in patients with exacerbations of chronic obstructive pulmonary disease.

Abstract

This study aimed to determine whether initiation of controlled oxygen therapy at ED presentation increased the proportion of patients with chronic obstructive pulmonary disease (COPD) achieving the COPD-X guideline target SpO2 range (88-92%) at 30 min and if it impacted total hospital length of stay or in-hospital mortality. Retrospective cohort study by medical record review of patients admitted to hospital with an exacerbation of COPD. The primary outcome of interest was the proportion of patients achieving the target SpO2 range at 30 min after ED arrival. The proportion of patients with SpO2 in the target range at 30 min was higher in the controlled oxygen therapy group (32% vs 16%: difference between proportions 16% (95% CI 7-24%); number needed to treat 6) and less likely to be over-oxygenated (SpO2 > 95%), 29% versus 54%, difference between proportions 25% (95% CI 14-35%); number needed to harm 4, without an increased likelihood of hypoxia. Length of stay was not different between the groups. Mortality for the controlled oxygen group was 2.7% (95% CI 1.3-5.5%) versus 5.8% for the uncontrolled oxygen group (95% CI 2.9-11.6%); however, this trend was not statistically significant. Patients with exacerbations of COPD receiving controlled oxygen therapy were more likely to achieve SpO2 within the COPD-X guideline target range without being more likely to be hypoxic. The proportion of patients with SpO2 within the target range was low, suggesting that further work on processes to optimise oxygenation in this group of patients is needed.