Question
How does peak expiratory flow measurement assist in the detection and management of airflow limitation in asthma?
Answer
Peak expiratory flow (PEF) measurement is a practical and accessible tool for detecting airflow limitation in individuals with asthma. Peak flow meters are inexpensive, portable devices available in both adult and pediatric versions, allowing patients to assess their respiratory function at home. These measurements provide objective data that can help patients recognize early signs of airflow obstruction, often before symptoms become severe. By documenting changes in peak flow over time, patients can detect patterns, anticipate asthma exacerbations, and take action early, potentially preventing more serious episodes.
Establishing a patient’s personal best peak flow during a stable period is essential. This personalized benchmark enables accurate interpretation of future readings, which can be used to assess symptom severity and guide treatment decisions. Patients are advised to perform three maximal expiratory efforts and record the highest of the three to ensure measurement accuracy. This data can be integrated into a written asthma action plan that categorizes results into zones—green, yellow, and red—each tied to specific management steps. In doing so, peak flow monitoring becomes a cornerstone of effective asthma self-management.
This Ask the Expert is an edited excerpt from the course, Objective Measures of Asthma, presented by Kevin Collins, PhD, RRT, RPFT, AE-C.