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Intermediate Technical IVT

peak expiratory flow rate

Pronunciation: peek ik-SPY-ruh-tawr-ee floh rayt

Maximum speed of expiration measured during a forceful breath out, used to assess airway function.

Full Definition

Peak expiratory flow rate (PEFR) is a measure of how fast a person can exhale air from their lungs, typically expressed in liters per minute. It represents the maximum flow rate achieved during a forced expiratory maneuver and is commonly used to monitor airway obstruction in conditions such as asthma. In pediatric pulmonology, PEFR measurements help assess disease severity, monitor treatment response, and detect early signs of respiratory deterioration. The test is performed using a peak flow meter and requires patient cooperation, making it most suitable for children over 5-6 years of age.

Usage

Usage note: Usually abbreviated as PEFR or peak flow in clinical documentation.

In Context

  • "Daily peak expiratory flow rate monitoring showed declining values prior to the asthma exacerbation." — Outpatient clinic note
  • "The patient's peak expiratory flow rate improved from 60% to 85% of predicted after treatment." — Progress note

Also known as

PEFR peak flow

Don't confuse with

forced expiratory volume minute ventilation

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