Fracción exhalada de óxido nítrico. Recomendaciones clínicas y procedimiento

Measuring the fraction of exhaled nitric oxide makes it possible to quantify «in an indirect, quick and reliable» fashion, the magnitude of airway infl ammation in patients with respiratory diseases; especially in cases of asthma. Because of its simplicity, this technique has also become a useful tool for diagnosing, monitoring and evaluating the therapeutic compliance in patients with asthma, among other conditions. In addition, measuring fraction of exhaled nitric oxide can help prevent exacerbations because it allows increases in infl ammatory activity to be detected and treated immediately. The purpose of this document is to review practical aspects of the fraction of exhaled nitric oxide-measuring technique using a portable device, and to provide clinical physicians with useful instruments that will aid in achieving correct interpretations of results. We consider the fraction of exhaled nitric oxide-measuring technique to be an underutilized test in current respiratory medicine practice, so our motivation is to make practical, summarized information available to readers.