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The measurement, by a form of gas meter, of volumes of gas that can be moved in or out of the lungs. The classical spirometer is a hollow cylinder (bell) closed at its top. With its open end immersed in a larger cylinder filled with water, it is suspended by a chain running over a pulley and attached to a counterweight. The magnitude of a gas volume entering or leaving is proportional to the vertical excursion of the bell. Volume changes can also be determined from measurements of flow, or rate of volume change, that can be sensed and recorded continuously by a transducer that generates an electrical signal. The flow signal can be continuously integrated to yield a volume trace.

The volume of gas moved in or out with each breath is the tidal volume; the maximal possible value is the vital capacity. Even after the most complete expiration, a volume of gas that cannot be measured by the above methods, that is, the residual volume, remains in the lungs. It is usually measured by a gas dilution method or by an instrument that measures blood flow in the lungs. Lung volumes can also be estimated by radiological or optical methods.

At the end of an expiration during normal resting breathing, the muscles of breathing are minimally active. Passive (elastic and gravitational) forces of the lungs balance those of the chest wall. In this state the volume of gas in the lungs is the functional residual capacity or relaxation volume. Displacement from this volume requires energy from natural (breathing muscles) or artificial (mechanical) sources. See Respiration



the measurement of the breathing capacity of the lungs. Spirometry was introduced in 1846 by the English scientist J. Hutchison.

Breathing capacity comprises the resting tidal volume of air that moves in and out of the lungs with each breath (approximately 500 cc), the inspiratory reserve volume of air that enters the lungs with maximal inhalation (approximately 1,500 cc), and the expiratory reserve volume of air that emerges from the lungs with maximal exhalation after normal exhalation (approximately 1,600 cc).

The breathing capacity of the lungs is usually measured with a spirometer (see Figure 1), which consists of a water-filled cylindrical tank that contains a floating cylindrical bell (1). The bell is

Figure 1

open at the bottom end and balanced by two counterweights. A rubber connecting tube (2) passes beneath the bottom of the bell. When a person forcefully exhales into the tube after taking a deep breath, the exhaled air forces the interior cylinder to rise. The volume of exhaled air is measured in cm3 according to a calibrated scale (3). Air is released from the spirometer by turning a valve (4).

The spirometer is used in examining healthy persons and in diagnosing and treating diseases of the lungs and cardiovascular system. In recent years spirographs have also been used to measure breathing capacity. Respiratory movements are recorded on spirograms, and breathing capacity is calculated according to special tables.



The measurement, by a form of gas meter (spirometer), of volumes of air that can be moved in or out of the lungs.
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Keywords: Forced expiratory volume in 1 second, Force vital capacity, Peak expiratory flow rate, Pulmonary function test, Spirometry.
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Pulmonary function tests were performed in order to estimate the forced vital capacity and CO diffusion capacity.
Pulmonary function tests were carried out by a portable Cosmed Pony FX brand Spirometer (Italy) while subjects were standing.
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Pulmonary function test showed mild hyperinflation, and severe air trapping.
Pulmonary function test (PFT) parameters are influenced by genetic factors, ethnic characteristics, environmental pollution, physical activity, altitude, and to a minor extent by nutritional and socioeconomical factors.
Thus, cigarette smoking has extensive effects on respiratory function, which can be detected with pulmonary function test.
In order to measure forced vital capacity LUNG TEST 1000 spirometr which is a static and modifier system designed for pulmonary function test, was applied.
Purpose: The purpose of this study was to analyze pulmonary function test results of track and crosscountry collegiate athletes based on type of athlete, and determine the relationships between years competing and percent of their predicted values.
The sample consisted of 1,357 pulmonary function test results and 1,129 total lung capacity measurements.

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