Final answer:
The normal finding when assessing the respiratory system of an elderly adult is the decreased mobility of the thorax due to the reduced elasticity of the lungs and chest wall structures with aging.
Step-by-step explanation:
Within the context of the respiratory system, particularly when assessing an elderly adult, certain changes are normal due to physiological alterations that occur with aging. One such change includes the decreased mobility of the thorax, which is associated with reduced elasticity of the lungs and chest wall.
This can lead to more rigid structures that do not expand as much during inhalation, affecting the overall respiratory function. Unlike younger individuals, the elderly may also exhibit a decreased anteroposterior diameter, which usually increases over a lifetime due to the changes in the spine and chest structure.
Lastly, bronchovesicular breath sounds are normal in certain areas of the lungs, but if heard throughout, they could suggest a pathological change such as pneumonia or other lung conditions.