Respiratory #1 part 2 Flashcards
What are the 3 airway zones?
Conducting zone
Transitional zone
Respiratory zone
3 characteristics of the conducting zone
Anatomical dead space
Gas movement by bulk flow
No role in gas exchange
In what zone do you hear airway sounds with your stethescope?
Conduction zone ???
3 characteristics of the transitional zone?
Cross sectional areas increase dramatically
Gas velocity decreases dramatically
Deposition of most inhaled particles
4 characteristics of the respiratory zone?
Gas movement by diffusion only
Entire surface available for diffusion
Capillaries form dense network in alveoli walls
Alveolar capillary membrane is .3-.5 um think
Why is it important that the alveolar-capillary membrane is thin?
Gas exchange by diffusion
Muscociliary escalator
Mucus secretion/clearance helps maintain airway integrity and pulmonary defense
(10-100mL of mucus secreted daily in humans)
What is provided by type I and type II Alveolus?
Alveolus Type I - lining
Alveolus Type II - secretes surfactant
Is Alveolus Type I or Type II more predominant?
Type II
What type of measurement is volume?
Flow?
Volume is static
Flow is rate
Minute ventilation formula
Vt x freq = 500ml x 15 breaths= 7.5 L/min
T or F: alveolar ventilation and pulmonary blood flow should be relatively equivalent?
True ???
How do you find alveolar gas?
tidal volume - anatomic dead space
What is the difference between
anatomical dead space and alveolar dead space?
Anatomical DS - portion of the breath that enter and leaves the conducting zones of the airways
Alveolar DS - air that reaches the alveoli but does not participate in gas exchange
Anatomic DS + Alveolar DS = ???
Physiological DS
What is physiological/function dead space?
Wasted ventilation
Increases with lung pathology
Ventilation/perfusion mismatch
How does different types of breathing affect
VA (Alveolar ventilation) and VT (tidal volume)?
Normal ventilation - normal (roughly 500 mL per breath)
Fast, shallow breathes - decreases VA, lower VT
Slow, deep breathes - increases VA, higher VT
Define Tidal Volume (VT)
The volume of air inspired and expired with each breath
Define Inspiratory reserve volume (IRV)
The maximum volume of air that can be inhaled beyond a normal TV
When is Inspiratory reserve volume (IRV) used
Exercise
Define Expiratory reserve Volume (ERV)?
The volume of gas expelled from the lungs during a maximal forced expiration beyond normal tidal expiration
Define Residual Volume (RV)
Volume of air left in the lungs after a maximal expiration
What 4 terms are primary lung volumes?
Tidal volume
Inspiratory reserve volume
Expiratory reserve volume
Residue volume
What 4 terms are secondary lung volumes?
Inspiratory capacity
Vital capacity
Functional residual capacity
Total lung capacity
Define Inspiratory capacity (IC)
Volume air inhaled into lungs during a maximal inspiratory effort that begins at the end of a normal tidal expiration
Formula for inspiratory capacity
IC= IRV+ TV
define vital capacity
Volume air expelled from the lungs during a maximal forced expiration starting after a maximal forced inspiration
formula for vital capacity
VC = IRV + TV+ ERV
Define functional residual capacity (FRC)
The volume of gas remaining in the lungs at the end of a normal tidal expiration
Formula for functional residual capacity (FRC)
FRC= ERV + RV
Define total lung capacity (TLC)
The volume of air at the end of a maximal inhalation
Formula for total lung capacity
TLC= IR+TV+ER+RV
Restrictive pulmonary disease
disorders with decreased lung volumes (decreased TLC, FRC, RV)
