Investigation of intrinsic disturbance wave near the end of expiration

Abstract

Based on the intrinsic disturbance wave (IDW) proposed by the author, a new type of flowmeter with differentiator and modified airway closing polygraph with indices of volume, moment flowrate, mean flowrate and time

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was designed. The results of individual (321 determinations in 7 cases) and population studies (clinical examinations of 370 cases) indicated that a correlation existed between the inflection point of intrinsic disturbance wave (IP-IDW) and pulmonary position with three regular patterns at volume axis near the end of expiration:

1.	Correlation with flowrate. If flowrate was defined between 0.3–0.5 1/s, definite IP was shown at the point when the mean flowrate ranged from more than 0.3 1/s to less than 0.3 1/s and the moment flowrate was 0.3 1/s in every examined case. From the data mentioned above CPV/VC % could be calculated.
2.	Correlation with age.
3.	Correlation with chronic obstructive pulmonary disease. This study also demonstrated that significant differences were found between the group of normal subjects, the groups of patients with chronic bronchitis, emphysema and chronic pulmonary heart disease and the group of other patients.

Keywords

intrinsic disturbance wave / inflection point of intrinsic disturbance wave / flowmeter with differentiator / airway closing polygraph / closing point volume

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