Lung function test/pulmonary function test/Spirometry
Spirometry is the most accurate breathing test for asthma. It measures how hard and fast you can breathe out. This test reflect overall lung function.
Spirometer is the machine which record the parameters.
Spirometer is useful to obtain the following:
To diagnosis of asthma
Check the severity of asthma
See if your asthma is getting worse
To see whether your asthma is getting better with treatment.
Most adults and children over 6 years of age can do the spirometry test correctly.
Steps of spirometry:
Sit upright in a chair.
Breathe in completely and rapidly.
Place the spirometer mouthpiece in your mouth and close your lips
to form a tight seal.
Breathe out as hard and fast and as long as possible.
Breathe in completely and rapidly again
Remove the mouthpiece
At least three standard reading is necessary to interpret the result.
Sometimes if required the test is done after taking ‘reliever’ medicine
Peak flow breathing tests
A peak flow test is done with a peak flow meter. It measures the maximum speed at which you can blow air out.
Your doctor may ask you to use a peak flow meter to check your asthma at home. Most children over the age of 6 years are able to use a peak flow meter correctly. However this text can’t be used as a confirmatory test for asthma.
Hold the peak flow meter level, so that the indicator faces upwards. Make sure the indicator is on zero.
Take a deep a breath.
Place your lips tightly around the mouthpiece and blow hard and fast.
Check your score on the meter
Repeat steps two more times
Record the highest score out of the three scores.
Compare with the chart of standard limits.
Interpret the result.
Spirometry and peak flow test may vary on their height, age and gender. So use local reference limit as standard.