How to use a Peak Flow Meter

A peak flow meter is a hand-held device that is used to measure the rate at which air can leave the lungs in people with asthma and other respiratory problems.



The rate measurable by this device is called the “peak expiratory flow rate” or “PEFR”.The device consists of a mouthpiece that leads to a another component that measures the speed of air passing through it, a dial or meter that gives the reading, and an opening for the air to exit from.
A slow peak expiratory flow rate indicates obstruction inside the lung airways.

What is the benefit of using peak flow meter device?

1. To the patient: The asthma patient can get an idea of how fit their  lungs are, also they can check whether they are improving or becoming worse. 
   
2. To the doctor: It provides the treating doctor with feedback on whether the treatment regimen is effective in controlling asthma symptoms, also repeated readings from different occasions might reveal patterns in the changes in the lung condition that might lead to diagnosis of an underlying cause (like an occupational allergy if the rates are worse around working days and improves on weekends).

How to use peak flow meter and precautions:

1. Make sure the dial is at the zero position.
   
2. Make sure the device is clean and does not contain any small objects (danger of choking if an unnoticed small object is inhaled).
   
3. Hold the device without blocking the air-exit part ,and without the fingers coming into contact with the dial or meter.
   
4. Take the deepest breath possible (BEFORE putting the device in the mouth ,do not inhale through the device).
   
5. Wrap the lips in an airtight manner around the mouthpiece , do not let the tongue close the opening of the mouthpiece!
   
6. Breathe out as powerfully possible and try to empty the lungs as quickly as possible.

This is repeated 3 times to get three readings, the average is taken.

How is the reading obtained this way interpreted?

1. Absolute: The reading is compared to readings on charts that contain the appropriate PEFR for age, height and sex.
   
   
   
   
   
2. Relative: Successive readings are recorded and the change in the readings indicate if there is an improvement or worsening of the condition of the lungs.