Takeheart Health Check      

Obstruction to air flow is commonly as a result of chronic bronchitis or emphysema. These are late manifestations of smoking and can be very distressing.

A majority of middle aged smokers will have chronic bronchitis.

Asthma is also characterised by an increased obstruction to the flow of air through your lungs.

Many asthmatics are poorly controlled. They tend to have low expectations for their breathing. (480)

To measure your peak flow rate you blow into a simple machine through a cardboard tube. It is not the amount of your breath that is measured but the speed at which it is expelled. Therefore it is important to give a hard but short puff.

The PFR normally varies with the sex, age and size of the person. This has to be taken into account when determining the significance of any particular reading.(5)

The Peak Flow measures the maximum speed at which air is expelled from the lungs. A forceful puff lasts about a second, but the result is expressed as litres per minute. Tables have been constructed to predict the peak flow rate in healthy people. Biological measurements are very variable so the predictions represent a mean value. Half the population will have a reading above the mean and half a reading below the mean. Healthy men may have a reading of up to 100 below the mean - 85 for women - and this is normal, as are all readings above the predicted mean.