Spirometry and peak expiratory flow in the primary care management of COPD

Spirometry is essential for the diagnosis of chronic obstructive pulmonary disease (COPD). In patients with COPD the decline in lung function is usually so slow that spirometry is unlikely to provide significantly new information more than every 1-2 years. However, it is useful to have an objective measure of lung function in the assessment of acute exacerbations of COPD and in the assessment of treatments. Peak expiratory flow (PEF) has been dismissed by national and international guidelines as an inappropriate test for the assessment of the impact of COPD, but with poor evidence in support of this position. This seems short-sighted since PEF is a reliable and reproducible test and could contribute to the management of COPD in the short term and in support of spirometry. As a result of infection or in response to treatment there may be changes in airway calibre in COPD which could be captured in the consultation by PEF. In a primary care setting spirometry is too time consuming and complex to be provided in the context of normal acute consulting. Furthermore there is no evidence that spirometry provides more information than PEF in the day-to-day management of a patient already diagnosed with COPD using forced expiratory volume in the first second/forced vital capacity (FEV1/FVC). Primary care teams should ensure that their patients have adequate access to high quality spirometry. This can be provided in primary care or in local centres or in hospitals depending on the interest, motivation and resources of primary care teams. In support of spirometry general practitioners (GPs) should then consider using PEF in the day-to-day management of COPD.