SPIROGRAPHY (Latin spiro to blow, breathe + grapho to write, represent) — a method of a research of function of lungs by measurement of pulmonary respiratory volumes.
Getchinson is considered the founder S. (J. Hutchinson, 1846), to-ry the first spirocount who found application in clinic designed and developed bases of ideas of pulmonary volumes.
Measure in liters or milliliters: respiratory volume — TO (air volume, inhaled and exhaled at each respiratory cycle; see the drawing to St. Vital capacity of lungs ); the reserve volume of a breath — RO vd (the maximum air volume, to-ry it is possible to inhale after a quiet breath); the reserve volume of an exhalation — RO vyd (the maximum air volume, to-ry it is possible to exhale after a quiet exhalation); vital capacity of lungs (see) — ZhEL (ZhEL = RO vyd + TO + PO vd ); the forced vital capacity of lungs — FZhEL (see. Votchala — Tiffno test ); functional residual capacity — FOE (amount of the gas which is in lungs after a quiet exhalation); residual lung volume — OOL (the volume remaining in lungs after the maximum exhalation), OOL = FOE — РО vyd ; total capacity of lungs — OEL (OEL = = ZhEL + OOL). The page allows to define also indicators of lung ventilation — the minute volume of breath — FASHION, maximal ventilation of lungs — MVL (see. Lung ventilation ), and also minute oxygen consumption to characterize uniformity of alveolar ventilation, to carry out tests with the forced breath and an exhalation.
By means of S. investigate mechanics of breath, estimate its disturbances and reserves of respiratory function. S. is especially important for assessment of therapeutic impacts on lungs and at medical control (see. Medical control ). Record of depth of breath (spirogramm) is a part of other methods of a research of function of lungs — estimates of distensibility of lungs, works of breath, reaction to carbon dioxide gas and a hypoxia.
The procedure is not traumatic. The research is conducted on an empty stomach or in 2 — 3 hours after a light breakfast. To the examinee enter a mouthpiece, through to-ry the contact with the device is made, on a nose impose a clip. At first register a spirogramma at quet breathing for determination of FASHION and oxygen consumption. Then suggest to make the deepest breath, for the Crimea the full deep quiet exhalation follows (for measurement of ZhEL, the District Department of Internal Affairs and R0VYD). After that suggest to make the deepest forced breath and the full forced exhalation (for measurement of FZhEL, Votchal's test — Tiffno and calculation of rates of volume flow of the movement of air at various moments of performance of tests). After a small break the examinee breathes within several minutes mix of air and helium which is used as the indicator for calculation of FOE, OOL, OEL, and also uniformity of alveolar ventilation (other plokhorastvorimy gases in blood can be indicators also: xenon or nitrogen during the filling of the spirocount with oxygen). The research is finished with definition of MB L; the examinee at the same time breathes with the maximum depth and frequency. The measured sizes of volumes lead according to tables to conditions of the BTPS system (from the English words Body, Temperature, Pressure, Soft): to temperature 37 °, to barometric pressure of 760 mm of mercury. and 100% of saturation by water vapors. Oxygen consumption is led to conditions of the STPD system (from the English words Standard, Temperature, Pressure, Dry): to temperature 0 °, to pressure of 760 mm of mercury. and to lack of water vapors. Results of inspection express in absolute values and percentage of due sizes for healthy people of the same sex, age, growth and weight (weight) of a body.
Decrease in the majority of indicators of S. by 20% and more from due sizes is regarded as a symptom of pathology; an adverse symptom is also increase in OOL and FOE. By results of S. establish existence and expressiveness of restrictive and obstructive disturbances. Restriction — difficulty of stretching of lungs and a thorax — is shown in reduction of pulmonary volumes (preferential OEL and ZhEL). At obstruction — deterioration in passability of respiratory tracts — speeds of the forced breath and an exhalation decrease, and also OOL and FOE because of the accompanying emphysema owing to obstruction of small, peripheral bronchial tubes increase. Pokazategl of obstruction of larger (central) bronchial tubes — decrease in FZhEL exhaled for the first second (see Votchal — Tiffno test). This indicator surpasses instantaneous values of speeds of the forced exhalation in sensitivity. A number of researchers claims that the moment of speed drop of the forced exhalation is an indicator of level of obstruction respectively in large, average or small bronchial tubes. Sometimes apply simultaneous record of volume and speed of the forced breath and exhalation — a so-called loop «volume — speed».
The mechanism of changes of a spirogramma at various diseases is various. Therefore its interpretation depends on the clinical diagnosis. So, e.g., decrease in high-speed characteristics of the forced exhalation sometimes is observed at absolutely healthy people and treated only as a factor of the increased risk of a disease of lungs. At the patient with bronchial asthma identical changes can form the basis to purpose of the corresponding treatment.
These S. have crucial importance in diagnosis of bronchial asthma. In the mezhpristupny period against the background of satisfactory condition it is sometimes long (for years) the increase in OOL and FOE testimonial of emphysema and obstruction of peripheral bronchial tubes remains. If at such patients speeds of the forced exhalation are significantly reduced, it is an indicator of obstruction of already central bronchial tubes. Cases of subjectively satisfactory condition at sharply changed S.'s indicators are typical for many patients who are on non-drug therapy (reflexotherapy, psychotherapy and so forth). On the contrary, sometimes on the basis of only one clinical picture the diagnosis of bronchial asthma whereas these S. reject this diagnosis as signs of a considerable bronchospasm even in the period of an aggravation are not found is made to neurotics.
On the basis of S. it is not possible to differentiate chronic diseases of lungs, however each disease has characteristic spiro-graphic signs. Those for chronic pneumonia and a pneumoconiosis is the combination of restriction and obstruction, for bronchial asthma — obstruction and emphysema. However cases when at patients hron meet. pneumonia emphysema and (or) obstruction, and at patients with bronchial asthma — restriction prevails.
Registration by means of S. of the forced exhalation before and after an exercise stress allows to estimate lability of bronchial tubes. Sharp increase of FZhEL and speed of its change after loading testifies to the increased tendency of bronchial tubes to expansion, it is observed at bronchitis, an asthmatic syndrome and predisposition to bronchial asthma. Falloff of indicators after loading (run, a veloergometriya) — a sign that in a pathogeny of bronchial asthma crucial importance has the bronchospasm caused by an exercise stress (so-called asthma of tension). The functional researches including S. which are carried out before inhalations of allergens, bronkhosuzhivayushchy and bronchodilatory means allow to establish an etiology of a disease or existence of its risk, expressiveness of allergic and bronkhospastichesky factors, help to pick up remedy and its dosage. For separate assessment of function of the right and left lung use a bronkhospirografiya. The research is conducted under anesthetic or local anesthesia, separately intubating right and left main bronchial tubes. The most important sign of defeat of one of lungs — decrease in consumption of oxygen by it in comparison with other lung. On informational content the separate bezintubatsionny S. on Bergana which is carried out without anesthesia at natural breath is close to this technique. The method gives an idea of participation of each lung in the general function of breath. To Spirogramm write down in position of the patient on spin and then serially on the right and left side at preservation of tight accession to the spirocount. About function of each lung judge by increase in FOE, to-ruyu measure on shift of the isoline of the spirogramma which is written down after a postural change of a body. The method has a number of restrictions. The village during the dosed exercise stress (ergospirografiya) allows to estimate working capacity; its main criterion is the gain of oxygen consumption during loading (see. Medical control).
Except S., use spirometry — measurement of respiratory volumes and ZhEL without record of a spirogramma.
Spirocolumns — devices for measurement of respiratory volumes. They join respiratory tracts of inspected and react to volume movements of air from lungs or in lungs. Spirocolumns, to-rye in one or both respiratory phases are reported with the atmosphere, call open; the spirocolumns having the message only with respiratory tracts — closed.
The elementary open spirocount is water. It consists of the cylinder filled with water, in to-ry the bell counterbalanced with a counterbalance and connected with the registrar is shipped by a bottom up. The cylinder has a tube, one end the cut is located over the water line under a bell, another is brought outside for connection to inspected. Inspected inhales air from the atmosphere (freely or via the valve of a breath) and exhales it in space under a bell therefore the bell rises by the size proportional to the volume of expired air, the feather of the registrar at the same time moves. There are also dry spirocolumns, in to-rykh a sensitive element the extensible fur which is reported with respiratory tracts, change of length to-rogo in the course of the breath inspected serves it is transferred to registrar. The devices measuring respiratory volumes by mathematical integration of rate of volume flow of the inhaled and expired air, edge also concern to spirocounts of open type is defined by the pneumotachograph (see. Pnevmotakhografiya ). The pneumotachographs equipped with analyzers of gases allow to define oxygen consumption and release of carbon dioxide gas in addition to respiratory volumes.
In spirocolumns of the closed type measurement of respiratory volumes is carried out essentially the same as in spirocolumns of open type. Except respiratory volumes and indicators of lung ventilation, it is possible to determine the saturating speed of oxygen by spirocounts of the closed type.
To Spirogramm most often write down mechanical registrars, feathers to-rykh are directly connected with the moving spirometric bell. Also electromechanical registrars reproducing changes of the voltage (current) created by the spirometric sensor or the integrator of the pneumotachograph are widely used. Use of two-coordinate recorders allows to register curves «volume — rate of volume flow».
The USSR produces in lots: the spirocount of open type «Spiro 2-25», registering in time volumes of breath at rest and at a moderate exercise stress inspected, the lung-tester of water 1-8B open type measuring the volume of expired air, the spirocolumn of the closed Metatest-1 and Metatest-2 type. For definition of OOL release the POOL-1 device. For the general and separate bronkhospirografiya release the Bronkhometatest-1 device measuring and registering in time volumes of breath and oxygen consumption of both lungs and each lung separately. For S. at newborns and children till 1 year release the lung-tester of Pedimetatest-1 measuring and registering TO, a respiration rate, FASHION, rate of volume flow of oxygen consumption. Entered also practice of the spirocolumn with elements of computer facilities, use a cut allowed to receive already during the research a large number of the defined and calculated indicators of function of external respiration and to correlate these indicators to due sizes.
Bibliography: Gavrilova N. I. and P e and and e L.E. Comparative assessment of a method of Bergan and bronkhospirometriya, Klin, medical, t. 55, No. 5, page 64, 1967; 3 I the blvd. e in Yu. P. and d river. Ventilating function of lungs, Alma-Ata, 1980, bibliogr.; Navratil M., Kadlec To. and D and at S. Patofiziologiya's m of breath, the lane from Czeches., Prague, 1967; H e m e r about Sunday to and y L. I. The analysis of designs of volume devices of gas exchange, Is new. medical technicians, century 6, page 3, 1961, century 1, page 3, 1962; The Guide to clinical physiology of breath, under the editorship of L. L. Shik and H. N. Kanayeva, L., 1980; The Reference book on functional diagnosis, under the editorship of I. A. Kassirsky, page 248, M., 1970; H u t with h i n-s about n J. On the capacity of the lungs and on the respiratory functions, with a view of establishing a precise and easy method of detecitng disease by the spirometer, Med. - chir. Trans., v. 29, p. 137, 1846.
M. I. Anokhin; V. I. Belkevich, V. S. Salmanovich (tekhn.).