[Differences in the elastic work of breathing of the pulmonary parenchyma in patients with bronchial asthma and COPD].

AIM: To determine and compare the work of breathing to overcome elastic resistance (Ael) in patients with bronchial asthma (BA) and chronic obstructive pulmonary disease (COPD) with similar changes in the elastic properties of the parenchyma in the same settings of ventilation disorders (grade 1). MATERIALS AND METHODS: Differences in the manifestations of similar changes in the elastic properties of the lungs in patients with BA and COPD were evaluated. To identify differences, a comparative study was conducted on Аel overcome in BA patients with positive bronchodilator (with salbutamol) and bronchoconstrictor (with methacholine) tests, with reduced and preserved bronchial conductance (groups 1 and 2, respectively), and in COPD patients with negative bronchodilator and bronchoconstrictor tests (group 3). All study patients showed a grade 1 lung ventilation disorder (a decrease in the one-second forced expiratory volume by 15-35%). The results were compared with each other and with the control group (group 4, healthy non-smokers). All study patients were comparable by age and sex. The respiration mechanics was studied using simultaneous registration of spirogram and transpulmonary pressure, and the parameters of bronchial conductance and ventilation were determined using body plethysmopressography using the Jager software and hardware system. RESULTS AND CONCLUSION: In COPD patients, Ael was significantly increased (p>0.05), whereas in both BA groups, it was unchanged. Increased elastic work of breathing in patients with COPD may be associated with the involvement of certain types of contractile elements, which are preserved in patients with BA at the initial stages of the disease.

[The theory of mechanical activity of lungs--a creation history, the present and development prospects].

In article the history of creation of the doctrine about respiratory movements of lungs, history of classical mechanics of breathing is stated. Supervision of the paradoxical facts which became a basis for hypothesis creation, then the theory of mechanical activity of lungs are presented. The facts proving mechanical activity of lungs on an inspiration and an expiration are given. Options of interaction of intra pulmonary and extra pulmonary sources of mechanical energy are considered. Theoretical justification for development of the new direction of studying of physiology of mechanical movements of the internal which does not have own skeleton is stated.

[Total non-elastic pulmonary resistance and permeability of the alveolar capillary membrane in community-acquired pneumonia].

AIM: To study alveolar capillary membrane permeability (ACMP) and total non-elastic pulmonary resistance (TNPR) in patients with community-acquired pneumonia (CAP) in an acute period. MATERIAL AND METHODS: ACMP of the lungs was studied in 35 CAP patients with ventilation pulmonoscintigraphy. Integral and regional TNPR were registered at inhalation and expiration. Integral TNPR was estimated by simultaneous registration of transpulmonal pressure and spirogram, regional TNPR (in the upper, middle and lower zones of the lungs)--by simultaneous registration of zonal rheograms of ventilation and transpulmonal pressure. Bronchial resistance was measured by body plethismograph (Masterlab pro, Erich Jaeger, Germany). RESULTS: In acute CAP integral TNPR rose while regional values varied. Both integral and regional ACMP for affected and intact lungs were significantly elevated showing systemic impairment of the structures of alveolar-capillary membrane of the lungs. More severe alterations of integral ACMP were seen in the affected lung, of regional--in the affected zones. CONCLUSION: Changes registered in regional TNPR and ACMP may indicate enhanced mechanical activity of the lungs in these zones. This enhanced activity contributes to TNPR overcoming.

[Mechanical properties of the lungs in bronchial asthma].

AIM: To evaluate basic parameters of elastic and nonelastic resistance of the lungs in patients with bronchial asthma (BA) with reference to severity of pulmonary ventilation disorder (PVD). MATERIAL AND METHODS: PVD was diagnosed in 92 BA patients aged 18 to 55 years (mean age 42 years, 50 males and 40 females). By PVD severity the patients were divided into 4 groups. The control group consisted of 65 healthy volunteers aged 18-54 years (mean age 45.6 years, 30 males and 35 females). PVD degree was assessed by reduction of respiratory capacity (RC) and forced expiratory volume per second (FEV1), volumes of the lungs, ventilation speed, bronchial resistance (Raw), total respiratory performance, total nonelastic resistance (TNR), total nonelastic pressure, dynamic lung compliance, static lung compliance (Cstat), elastic lung traction (ELT). RESULTS: A RC fall in groups 2-4 was less significant than FEV1 reduction. Raw was elevated in all the groups: in group 2 the rise was more than in group 1, but in groups 3 and 4 the rise was similar. TNR at inhalation and exhalation increased from group 1 to group 3, was high in group 4. Cstat and ELT were similarly subnormal in all the groups. CONCLUSION: Elevation of bronchial resistance does not influence PVD severity. Lowering of FEV1 only partially is related with Raw elevation. Subnormal lung compliance may represent a compensatory reaction directed to overcoming valvular bronchial obstruction and maintenance of normal lung ventilation. Low lung traction may result from high mechanical activity of the lungs in condition of its estimation.