Сharacteristics and nature of nonxelastic pulmonary resistance changes according to lung regions in case of community-acquired pneumonia

Aim: to study and characterize regional changes of non-elastic pulmonary resistance (NPR) and compare these data with regional values of alveolar#capillary permeability (ACP) in patients with community-acquired pneumonia (CAP). 29 CAP patients underwent evaluation of the regional NPR values (in the superior, central and inferior lung lobes) by means of simultaneous recording of zonal ventilation rheograms and transpulmonary pressure as well as ACP by the method of ventilation pulmoscintigraphy. Also the Masterlab Pro body plethysmography system (manufactured by the Erich Jaeger Company, Germany) was used to measure bronchial resistance. The integral total non-elastic pulmonary resistance (TNPR) increases in case of CAP; at the same time, the regional TNPR changes are non-uniform. Both the integral ACP values in the affected and intact lungs and the regional ACP values in the affected and intact lung lobes were significantly increased in case of CAP, which testifies to generalized affection of the structures of the alveolar-capillary membrane of the lungs. Taking into account the detected generalized increase of ACP, it seems that the mechanism of the TNPR increase consists in the change of inspiratory-expiratory blood filling of the lungs as well as respiratory fluctuations of the degree of intensity of the alveolar and interstitial inflammatory edema. The achieved results of the changes in the regional TNPR and ACP values testify to the increased intrinsic mechanical activity of the lungs in these areas. This increased activity contributes to overcoming a significant part of the total non-elastic pulmonary resistance.