Respiratory definitions (lung volumes, etc.) Flashcards
What does TLC stand for and what is the definition?
Total Lung Capacity: the total volume of air that the lungs can hold (5.7L)
What does TV stand for and what is the definition?
Tidal Volume: is the volume of air entering or leaving the lungs during a single breath (0.5L)
What does IRV stand for and what is the definition?
Inspiratory Reserve Volume: extra volume of air that can be maximally inspired over and above the tidal volume (3.0L)
What does ERV stand for and what is the definition?
Expiratory Reserve Volume: extra volume of air that can be breathed out/ expired over and above the tidal volume (1.0L)
What does RV stand for and what is the definition?
Residual Volume: is the minimum volume of air remaining in the lungs even after a maximal expiration. It increases with age/ emphysema.
What does IC stand for and what is the definition?
Inspiratory Capacity: is the maximum volume of air that can be inspired at the end of a normal quiet expiration (3.5L)
What does FRC stand for and what is the definition?
Functional Residual Capacity: is the volume of air in the lungs at the end of a normal passive expiration (resting lung volume) (2.2L)
What does VC stand for and what is the definition?
Vital Capacity: is the maximum volume of air that can be moved out during a single breath following a maximal inspiration. (4.5L)
4500ml = males
3500ml = females
State LaPlace’s Law
LaPlace’s law states that the smaller alveoli have a higher tendency to collapse
State Boyle’s Law
Boyle’s law states that the pressure exerted by a constant number of gas molecules in a container is inversely proportional to the volume of the container
State Dalton’s Law
Dalton’s law states that the total pressure exerted by a gaseous mixture is equal to the sum of the partial pressures of each individual component in the gas mixture
State Fick’s Law of Diffusion
Fick’s law of diffusion states that the amount of gas that moves across a sheet of tissue in unit time is proportional to the area of the sheet but inversely proportional to its thickness
State Henry’s Law
Henry’s law states that the amount of given gas dissolved in a given type and volume of liquid at a constant temperature is proportional to the partial pressure of the gas in equilibrium with the liquid
What is intra-pleural fluid cohesiveness?
it is when the water molecules in the intra-pleural fluid are attracted to each other and resist being pulled apart. Hence, the pleural membranes tend to stick together.
What is negative intra-pleural pressure?
this is when the sub-atmospheric intra-pleural pressure create a transmural pressure gradient across the lung wall and across the chest wall. So, the lungs are forced to expand outwards while the chest is forced to squeeze inwards.
