peak flow

A peak flow meter is a small, hand-held device used to manage asthma by monitoring airflow through the bronchi and thus the degree of restriction in the airways. The peak flow meter measures the patient's maximum ability to expel air from the lungs, or peak expiratory flow rate (PEFR or PEF). Peak flow readings are higher when patients are well, and lower when the airways are constricted. From changes in recorded values, patients and doctors may determine lung functionality, severity of asthma symptoms, and treatment options.
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Peak flow meter n. A portable instrument that detects minute decreases in air flow and that is used by people with asthma to monitor small changes [more]Peak flow - Community and Resources