Practical 7: Lung Mechanics Flashcards
what is the tidal volume TV
the volume of air exchanged during normal inspiration or expiration
inspiratory reserve volume IRV
the maximal volume that can be inspired in addition to a tidal inspiration
expiratory reserve volume ERV
the maximal volume that can be expired in addition to a tidal expiration
residual volume RV
the volume of air remaining in the lungs at the end of a maximal expiration.
why cant residual volume be measured using an ordinary spirometer
it cannot be breathed out
inspiratory capacity IC
the maximal volume of air thar can be inhaled after normal expiration (IC = TV + IRV)
vital capacity VC
the greatest volume that can be exhaled after maximal inspiration (VC = TV + IRV + ERV)
Functional residual capacity FRC
the volume of air remaining in the lungs after normal expiration (FRC + ERV + RV)
total lung capacity TLC
the volume of air in the lungs at the end of a maximal inspiration (TLC = VC + RV)
restrictive respiratory tract disorders
where the lungs ability to expand is impaired eg pulmonary fibrosis
obstructive respiratory tract disorders
caused by obstruction or narrowing of the airways eg asthma
FEV1
the volume of air expelled over the first second of the exhalation
what improvements could you make to experimental design
control other factors such as gender, smoking etc so that the only thing affecting FVC is height
factors affecting lung capacities
gender, age and height
what could be the causes for discrepancies
make sure mouthpiece inserted with seal
machine not set up correctly
poor technique
experience
