peak expiratory flow rate
Also written as: PEFR — Peak Expiratory Flow Rate
Maximum flow rate achieved during forced expiration, measured to assess airway obstruction and monitor respiratory conditions.
Full Definition
Peak expiratory flow rate (PEFR) is a simple measurement of the maximum speed at which air can be expelled from the lungs during a forced expiration after full inspiration. Measured in liters per minute, PEFR primarily reflects the caliber of large airways and the strength of expiratory muscles. The test is performed using a peak flow meter, a portable device that allows for frequent monitoring in both clinical and home settings. PEFR values vary with age, height, sex, and ethnicity, with individual patients often establishing personal best values for comparison. This measurement is particularly valuable for monitoring asthma control, detecting early signs of exacerbation, and assessing response to bronchodilator therapy. Daily PEFR monitoring helps patients and clinicians track disease patterns and adjust treatment accordingly.
Usage
Usage note: Commonly abbreviated as PEFR or peak flow in clinical documentation.
In Context
- "The patient's peak expiratory flow rate dropped to 60% of their personal best, indicating worsening asthma control." — Outpatient clinic note
- "Daily peak flow monitoring revealed a 20% improvement following initiation of inhaled corticosteroid therapy." — Follow-up assessment