Influence of hyperventilation on the dynamic of Carbon (IV) Oxide in alveolar air

Introduction . Hyperventilation occurs under the influence of environmental factors, neuro-psychic stress, in sports activities, with the introduction of pharmacological substances, accompanies a number of diseases. However, there are insufficient studies of the individual peculiarities of СО 2 change dynamics in the alveolar air at hyperventilation test and after it. Purpose . To analyze the dynamics of changes in the level of carbon (IV) oxide in the alveolar air while testing the regulated respiration with a frequency of 30 cycles per minute in healthy young men. Methods . Measurements were performed on 81 healthy young men aged 18-22. The level of СО 2 in the exhaled air was determined in the lateral flow by the infrared spectrometry method on the capnograph Datex Normocap (Finland). The stress of СО 2 in the alveolar air was estimated according to its level at the end of the exhalation (PetCO 2 ). Results . At the respiration with a frequency of 30 cycles per minute 1 for 10 minutes, the level of PetCO 2 decreases from 40.12 ± 0.361 mm Hg to 18.59 ± 0.542 mm Hg.  In the 40-minute recovery period after the test, the return of PetCO 2 to the initial level does not occur. There are significant individual peculiarities of PetCO 2 reactivity to hyperventilation and recovery after it. Originality . It has been shown that the stress reactivity of carbon (IV) oxide in the alveolar air to a sample with respiration of 30 cycles per minute and after recovery after it depends on its initial level – the lower the level of Pet CO 2 , the lower the reactivity and the faster recovery. The stress reactivity of carbon (IV) oxide in the alveolar air to testing respiration of 30 cycles per minute and to the recovery during the first 5-10 minutes after it depends on the initial respiration rate. Conclusion . When evaluating a hyperventilation test, the initial level of СО 2 in the alveolar air and respiratory rate should be taken into account.