Spirometry is called the ventilation test that is performed to diagnose the condition of the respiratory system. Spirometry allows you to measure the volume of the respiratory system, the volumetric air flow rate and ratio, lung capacity, the capacity of the entry and exit, maximum ventilation.
Spirometry provides an opportunity to identify lung disease and cardiovascular disease, assess their severity, the effectiveness of treatment. In addition, the test helps to learn how to breathe correctly.
It is estimated that each year undergo spirometry must be smokers: survey will help to identify pulmonary dysfunction at an early stage, differential diagnosis of asthma, chronic obstructive pulmonary sarcoidosis.
Contraindications this method of diagnosis is not present, including age limit: carried out spirometry in children and in adults.
The procedure of examination in spirometry
Spirometry is performed using a special device for continuous graphic recording changes in the volume of air inhaled and exhaled - spirograph. In the device for each patient put on a new disposable mouthpiece.
The subjects were asked to make a very deep breath, hold your breath, pressed his mouth as tightly as possible to the die (from now beginning to be recorded on the device) and evenly and calmly dialed exhale all the air. In patients suffering from chronic obstructive pulmonary disease, it may take about 15 seconds. After the tidal patient should do the same, but to make every effort.
A similar procedure, the patient repeats two more times, and received three groups of indicators used by doctors to decrypt spirometry.
Most indicators spirometry expressed as a percentage of the average values of physiological variables. The rate ranges from 80-120%. In deciphering the spirometry can be found such indicators:
- Tidal volume - the amount of air per breath to the lungs during passive exhalation. Norma - 500-800ml;
- VC - vital lung capacity - the amount of light that comes out when you exhale. This figure is significantly reduced with restrictive lung disease;
- FZHEL1- forced vital capacity of the lungs. This figure is similar to the previous spirometry, but the patient should exhale produce at the highest possible speed and with the greatest possible effort.
- FEV1 - forced expiratory volume in 1 second. The amount of air that flows out of the lungs in the first second of exhalation with maximum force. These data spirometry in children and adults reflect the state of the large airways, expressed as a percentage of lung capacity. The rate of forced expiratory volume - 75%.
- Index Tiffno. The percentage of FEV1 to FVC. Its rate - 70% and more.
- Average volume rate. Measured as a percentage - 25-75%. It indicates the condition of the small airways. The flow rate is useful for early detection of obstructive disorders.
- The peak expiratory volume velocity. The maximum speed that a person can show enhanced when you exhale.
- Airway. It depends on the efforts of the muscles, displays the condition of the respiratory system at the level of the large bronchi, trachea.
Since these figures are taken from a patient three times in deciphering spirometry doctor takes to analyze the best result and compares it to the performance standards for the respective groups of people: the growth is taken into account, gender, age of the patient.