The use of oxygen in acute exacerbations of chronic obstructive pulmonary disease: a prospective audit of pre-hospital and hospital emergency management.

Treatment with high-flow oxygen in acute exacerbations of chronic obstructive pulmonary disease (AECOPD) can cause or aggravate acute hypercapnic respiratory failure and adversely affect prognosis. National guidelines for the management of COPD recommend an initial fractional inspired oxygen concentration (FiO2) of no more than 0.28. However, a prospective audit of 101 consecutive episodes of AECOPD demonstrated that oxygen therapy with an FiO2 in excess of 0.28 is common, potentially deleterious and predominantly initiated in the ambulance. Patient awareness, aids to disease identification and ambulance protocols are likely to hold the key to improvement in the acute care of these patients.