COMPLETE SOLUTIONS
◉ What two factors provide resistance to lung stretch/elasticity?
Answer: Elastic and Collagen Fibers
◉ The application of what forces causes the lungs to stretch until
maximum inflation? Answer: Pressure
◉ Hysteresis Answer: The difference between lung inflation and
deflation curves. Has a direct relationship with surface tension
◉ On a volume-pressure, the bottom line illustrates _________, and the
top line illustrates __________ Answer: Inspiration, Expiration
◉ Achieving a higher lung volume requires an increase in what?
Answer: Pressure
◉ What is limited in a fluid-filled lung? Answer: Hysteresis and
Surface Tension
◉ What factors cause lung recoil? Answer: Tissue Elasticity and
Surface Tension
,◉ Inhalation requires _______ pressure to achieve a given volume
than exhalation Answer: More
◉ Volume-Pressure Curve + Ideal Shape Answer: Illustrates the
relationship between volume and pressure on inspiration and
expiration in a particular case. A healthy lung demonstrates a
football shaped curve
◉ Hysteresis in a volume-pressure curve is highly dependent on
what factor? Answer: Surface Tension
◉ What surrounds the alveoli? Answer: Water and Pulmonary
Surfactant
◉ Pulmonary Surfactant Answer: The liquid that reduces surface
tension in alveoli
- Produced in type II pneumoncytes
- Stabilizes alveoli to prevent collapse
- The more surface area to an alveoli, the more pulmonary surfactant
is used/needed
, ◉ Lung Compliance (CL) Answer: Change in lung volume caused by
a given change in transpulmonary pressure; the greater the lung
compliance, the more readily the lungs are expanded
◉ CL Answer: Lung Compliance/The change in lung volume per
change in pressure
◉ Lung Compliance (CL) Formula Answer: CL= ∆P/∆V
∆P= Change in pressures
∆V= Change in volumes
◉ What is the average Lung Compliance (CL) in a healthy lung and
chest wall? Answer: 0.2 L/cm H20
◉ What is the effect of Emphysema on CL? Answer: Increases CL.
Loss of elasticity prevents the lungs from recoiling and keeps them
inflated (No rubber in the rubber band)
◉ What is the effect of Pulmonary Fibrosis on CL? Answer:
Decreases CL. Increase in elastic scar tissue that prevents the lungs
from fully inflating