Pathological physiology and functional diagnostics. When emphysema change of lung volumes and ventilation function of the light, the broken relationship between ventilation and circulation, and may increase the pressure in the pulmonary artery.
Lung volumes [of vital capacity of the lungs (VC) and other] decreases are usually only apparent cases of emphysema, mainly due to additional volume exhalation. The main feature of emphysema is the increase of residual lung-volume century absolute terms and in percent to total volume. OK, Balto (W. Bolt), the residual amount is 25% of the total. In mild emphysema - 35%, with emphysema moderate-35-45%, in severe emphysema - 45-55%, with heavy - more than 55% of the total. On Kumano (A. Cournand) et al., residual volume increases with age, and in people over 50 years up to 40% of the total. Residual volume consists of; alveolar residual volume and air, filling airway; (dead space). When emphysema increased both.
Due to the increased resistance in the bronchi reduces the amount of air passing through the bronchi Max. voltage respiratory muscles, decreases "power" and exhalation, defined by pneumotonometry. (Pneumotachography - continuous recording speed of inhaled and exhaled air jet in every moment of the respiratory cycle. The device with such recording device called pneumotachogram. When replacing the recording part gauge turns out the peak meter.)
Should the amount determined by the formula G. Badalyan: power exhalation in litres shall not be less than 85% of the actual VC, multiplied by 1.2. This formula is valid only for VC, not exceeding 100%. Simpler approximate norm is the following: pnevmaticheskie data exhalation should not be less than the actual VC. Measure bronchial resistance is the attitude vnutricerepnogo pressure to a higher rate of air stream. To measure bronchial resistance in this way you can use pneumotachography.
Sample tiffno (forced VC per 1 sec.) detects decrease sometimes up to 30% of all VC. Ventilation is uneven, as the narrowing of the bronchi unevenly. Better ventilated alveoli, which are suitable bronchioles with a broader level. The maximum amount of ventilation, the provision of ventilation and speed index breathing reduced. Irregularity ventilation detected when determining residual lung-volume methods - helium, xenon or leaching of nitrogen (using atmograf).
OK uniform mixture is additionally introduced a gas with alveolar air occurs in 1-2 minutes (not more than 3 minutes), while emphysema is 10 and even 15 minutes
The broken relationship between ventilation and air circulation. In physiological atelectasis when reducing ventilation at the same time the circulation. In pathology, especially in the final stages of emphysema with a gross anatomical changes of the alveolar walls, divide and merge the alveoli, violated this thin regulation. Reduce saturation of arterial blood oxygen occurs in two cases. If the blood flow in the alveoli significantly reduced, l ventilation reduced slightly or remained normal, part of the ventilation air is not involved in the gas exchange (increases dead space). If in some areas circulation remained normal and ventilation decreased, blood flowing from them undersaturated, reducing the General level of saturation of blood with oxygen. Further violated the excretion of carbon dioxide (hypercapnia).
Increases (at first only under load) the pressure in the pulmonary artery (see Pulmonary heart disease).
Accordingly functional disturbances were suggested different classification of the stages of development of emphysema. So, Menshikov Palace, Zislin highlights the latent pulmonary, clear pulmonary and pulmonary-cardiac insufficiency.
Very significant for the characteristics of the patient with emphysema statement of indicators ventilation and gas exchange deficiency not only at rest and during exercise, but especially under the influence of different means of influencing bronchial passability (broncholytic, anti-edematous and anti-inflammatory, including steroids).