The influence of pulmonary growth and development on paediatric respiratory diseases.

The mortality, morbidity and symptomatology of respiratory diseases in infants and children may be partially related to age specific phenomena of structure and function. Such are the comparatively smaller functional residual capacity and respiratory surface area; the difference in growth velocity of alveolar numbers and size; the smaller number of intrapulmonary communications; the larger resistance of the peripheral airways accentuated by fewer muscular elements and larger number of mucous glands in the same; and the smaller elastic recoil pressure of the lung in children as compared to adults. Many factors compensate, partially or totally, for these apparent handicaps, but the influence of growth and development on disease processes can certainly not be disregarded.