PEFR Test: Peak Expiratory Flow Rate Explained

What is peak expiratory flow rate?

Peak expiratory flow rate (PEFR) or ‘peak flow’  is a simple bedside test of lung function, most commonly used in people with asthma or chronic obstructive airways disease (COAD).

How is a PEFR test performed?

A PEFR test is a quick and simple bedside measurement. A small tube with a slider device measures how fast air is driven through the tube by the subject exhaling rapidly.

The subject takes a deep breath in, then breathes out as hard and as fast as possible, with a good airtight seal of the lips around the tube.

This is best done standing up; the best of three attempts is usually taken, with a short rest between attempts.

When would you need a PEFR test?

A PEFR may be requested by your doctor for symptoms such as shortness of breath (dyspnoea), cough or wheezing.

PEFR test results explained

The normal range for peak fow measurements depends on your gender, age, and height.

There is a reasonable ‘spread’ of normal values for any group of people with the same age, height and gender.

The individual’s “personal best” measurement is a more reliable guide to predicting an asthma attack or assessing the severity of illness.

Related specialists

• Respiratory Physician
• General Practitioner (GP)
• General Physician
• Anaesthetist
• Occupational Health Physician
• Emergency Physician

Related tests

• Respiratory Function Tests (RFTs)
• Chest X-Ray (CXR)
• CT Scan of the Chest
• Bronchoscopy

Also known as

• Peak flow
• PEFR

Links

• National Asthma Council Australia
• The Australian Lung Foundation
• Peak Flow Information (Europe)
• Wikipedia – Peak expiratory flow

This article is for informational purposes only and should not be taken as medical advice. If in doubt, HealthEngine recommends consulting with a registered health practitioner.