Respiratory system 1 part 1 Flashcards
What is spirometry?
It is the measure of lung volumes and capacities using a device called a spirometer. It is a useful tool for assessing lung function.
Define tidal volume and give its normal value
It is the difference between inspiration and expiration during quiet breathing. volume: 500mL
Define expiratory reserve volume and give its normal value
It is the maximum volume of air that can be forcibly expired after the end of normal tidal expiration. (1100mL)
Define inspiratory reserve volume and give its normal value
It is the maximum volume of air that can be forcibly inspired over and above normal tidal inspiration. (3000mL)
Define residual volume and give its normal value
It is the volume of air remaining in the lungs after most forceful expiration. (1200mL)
Define inspiratory capacity and give its normal value
It is the amount of air a person can breath in, beginning at the normal expiratory level & distending the lungs to the max amount (TV + IRV—> 3500mL)
Define functional residual capacity and give its normal value
It is the amount of air that remains in the lungs at the end of normal expiration. (ERV + RV = 2300mL)
Define forced vital capacity and give its normal value
Maximum amount of air a person can expel from the lungs after 1st filling the lungs to their max extent & then expiring to the max extent = TV + IRV + ERV (4600mL)
Define total lung capacity and give its normal value
Maximum volume to which the lungs can be expanded with the greatest possible effort = TV + IRV + ERV + RV OR VC + RV (~5800mL)
What does the expiratory flow-volume curve depict?
Performance of forced vital capacity (FVC) maneuver (inspiring to TLC
and then exhaling as forcibly as possible to RV).
Define anatomical dead space
Volume of air present in conducting
airways is termed the anatomical dead space (VDS). It does not participate in gaseous exchange
Which parts of the conducting airway form the anatomical dead space?
Everything above the respiratory bronchioles
What are the implications of anatomical dead space?
Alveolar ventilation < tidal volume and minute ventilation, due to air remaining in
the conducting respiratory tract (airways) and does not reach alveoli.
Define physiological dead space
Alveoli being ventilated but not perfused.
Total volume of gas in each breath not participating in gas exchange = physiological dead space ventilation.
What is ventilation?
Movement of fresh air in and out of the lungs.
