Peak Flow Meter

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Mini Peak Flow Meter (PEFR)This is a small and simple instrument which can be used by the patients. The patients blows into the instrument (Peak Flow Meter) and it gives an indication of the patients lung function (PEFR – Peak Expiratory Flow Rate). It can be useful in

o    Assessing patient’s daily condition.

o    As a warning to the patient (impending attack).

o    To check for the effect of the medicines given.


How to use the Peak Flow Meter

Step I    – Slide the indicator to zero (0)

Step II   – Stand up and take a deep breath, then clasp your lips around the mouth piece of the instrument.

Step III  – Now blow out as hard and as rapidly as you can into the mouth piece.  ( Do not put your tongue into the mouth piece hole) (Do not obstruct the indicator with your fingers).

Step IV  – Read the value as indicated by the instrument.

Please note down the best of three readings.


How to calculate your personal best Peak Flow

  • The “personal best” Peak Flow (PEFR) is defined as the highest peak flow rate you can attain, over a 15-21 day time period, when your asthma symptoms are fully under control.
  • The Peak Flow (PEFR) should be measured twice a day (Early Morning and Evening, preferably 12 hours apart) at the same time each day before using reliever medicines.