BIO 219: LAB 17 - Spirometry

method of measuring ventilation volumes in real time. Traditional spirometers measure displacement of air during breathing in a closed system. Used to measure standard lung volumes and capacities and can also be used to preform pulmonary function test pulmonary disorders

defines the relationship between gas pressure and volume

↓ V ↑ P
↑ V ↓ P

Total volume of air in the lungs at maximal inspiration

RV + ERV + IRV + VT

represent the maximum ventilation volume from maximal inspiration to maximal expiration

VT + IRV + ERV

volume of air that passes into and out of the lungs during normal relaxed breathing

maximum volume that can be inspired following a normal expiration
VT + IRV

maximum volume of air that can be inspired into the lungs following a normal inspiration

maximum volume of air that can be expired forcefully from the lungs following normal expiration

maximum volume that can be expired after normal expiration

VT + ERV

volume of air remaining in the lungs following normal expiration

RV + ERV

minimum volume of air that remains in the lungs following maximum expiration

volume increases, pressure falls
• air flows in

volume decreases, pressure rises
• air flows out

Reduced FEV, normal between 75%-85% asthma, bronchitis, emphysema caused by constriction or blockage of bronchioles.
• expiration

pulmonary fibrosis
• reduced lung compliance - makes it difficult to expand lungs during inspiration
• shows a reduction in vital capacity