Many times people with lung problems go to their doctor and are advised that they need a spirometry test; however, many patients have never heard of this procedure and immediately ask their doctor – what is spirometry? Fortunately, it is a relatively easy procedure that simply requires exhaling into a special tube designed to help measure the patient’s lung function.
Whether you have asthma, cystic fibrosis, pulmonary fibrosis, COPD or some other type of lung disorder, the use of spirometry can help your doctor not only diagnose or monitor your condition, but can also give them valuable information on how best to treat your particular problem. The spirometer is able to measure not only how much air was released by the patient, but depending on the particular meter used, it can also measure how quickly it was released. This is an excellent tool to use in determining how well a patient’s lungs are functioning.
When a patient performs the spirometry test, some doctors prefer to have them wear a nose clip. This helps to ensure that all air being released is measured by the spirometer and does not escape out the nose causing an inaccurate reading. The patient should be advised to take a couple of deep breaths before beginning the test. When the patient is ready, they should inhale deeply, then as quickly and as hard as possible they must exhale into the special tube on the spirometer. The procedure is sometimes repeated a couple of times to get a good reading because it is easy for the patient to not fully complete the procedure exactly as necessary. Sometimes a quick demonstration by the doctor or nurse performing the test can help ensure that the patient fully understands how to blow hard and fast.
Once the results are calculated by the spirometer a pneumotachograph is generally printed and can be placed in the patients chart for future reference and comparisons. The results can also be reviewed by the doctor and patient. The results of spirometry are calculated by comparing the patient’s results with those of healthy individuals of the same age, sex, height and weight. With the information from this simple test a doctor can determine if current treatment plans are working as planned or if medication and other treatment options should be implemented.
The Spirometer takes two separate measurements; the first measurement is the amount of air a patient is able to expel in a single second. This measurement is referred to as the forced expiratory volume or FEV1. The other measurement is known as the Forced Vital Capacity or FVC, this is a measurement of the volume of air a patient expels during the testing process. These two figures are then compared. If the ration between these two measurements is less than 70%, the patient may have abnormal lung function.
There are other tools that can be used to help doctors determine pulmonary function; however, the spirometer is one of the most common PFTs or Pulmonary Function Tests currently in use.