title: Elastic behavior of postmortem human lungs: effects of aging and mild emphysema.
abstract: The elastic behavior of postmortem human lungs has been studied in an effort to differentiate the effects of normal aging from those of mild emphysema. Static pressure-volume (P-V) curves were measured in 50 lungs obtained from men 15-85 yr of age, including 12 lungs with mild-to-moderate emphysema. The emphysema was quantitatively assessed by gross and microscopic methods. The P-V relationship in all lungs is accurately described by the empirically fitted equation, P = alpha1ea2v. This expression is useful because the two parameters separate the effects of elastic behavior (alpha1) from size (alpha2) on the P-V curve. There is a close negative correlation (R = -0.94) Between age and alpha1 in normal lungs but no significant age dependence of alpha2. Further decreases in alpha1 are found in most emphysematous lungs. Alpha1 is more than 2 SEE below the age-predicted mean in five of nine lungs with minimal emphysema (1-10% by point count) and more than 5 SEE below the mean in the three more severely affected lungs. There is a close correlation (R = +0.90) between alpha1 and the alveolar surface-to-volume ratio in both normal and emphysematous lungs.
mesh_terms: D000293:Adolescent; D000328:Adult; D000367:Age Factors; D000368:Aged; D004548:Elasticity; D006801:Humans; D008168:Lung / Q000503:physiopathology*; D008297:Male; D008875:Middle Aged; D011650:Pulmonary Alveoli / Q000503:physiopathology; D011656:Pulmonary Emphysema / Q000503:physiopathology*