[Configurations of F-V curve and their transformation rule in COPD patients analysed with wave-speed theory].
This study sought to analyse the mechanism on the formation of configurations of F-V curve and their transformation rule in COPD and cor pulmonale patients with wave-speed theory. The F-V curves were measured in 90 COPD patients (43 with chronic bronchitis, 47 with emphysema) and 31 complicated with cor pulmonale, all of them were in the ameliorated period. The indices selected were FVC, V75, V50, V25. Both the measured value and the measured value/predicted value (%) of all indices showed chronic bronchitis > emphysema > cor pulmonale. Never was there the concave type of normal humans in the F-V curves of COPD and cor pulmonale patients; however, the convex type was much increased in the curves and the hyperbolic type specific to COPD and cor pulmonale appeared. The mechanisms of formation for plateau, convex and hyperbolic types were analysed with the wave-speed theory. In summary, the unifying rule for the transformation of F-V curve configuration from normal adolescents to old persons, smokers, COPD and cor pulmonale patients in various degrees can be outlined as, concave type normality convex type abnormality hyperbolic type. This implicates a unifying process of pulmonary functions from healthy state to weakness and from slight to serious abnormality.