Measurement of Exhaled Nitric Oxide in the Emergency Department in Patients with Asthma

A great deal of research has been conducted on the utility and usefulness of exhaled nitric oxide (NO) as a biomarker of airway inflammation and its role in the diagnosis of acute asthma exacerbations. This article reviews the pathophysiology of NO in asthma, evidence for the use of exhaled NO in acute asthma exacerbations, and the potential utility of devices available to emergency physicians for measuring exhaled NO.