lect-22 Pulmonary ventilation Flashcards
what is respiratory epithelium
pseudo stratified ciliated columnar epithelium with goblet cells
what type of cartilage rings are in the trachea
incomplete cartilaginous rings
where are the carina located and what are they sensitive to
inside trachea at point of branching of primary bronchi
sensitive to irruption
produces cough reflex
what do the primary bronchi supply to
lungs
what do the secondary bronchi supply
lobes
what do the tertiary bronchi supply
lobules
what type of cartilage is in bronchioles
NONE
where is the first place in the respiratory tree that you can get gas exchange
respiratory branches of bronchioles
what respiratory muscles are inspiratory
respiratory diaphragm external intercostal muscles (limited) sternomastoids serratus anterior muscles scalene muscles
what muscles are form forceful expiration
abdominal muscles
internal intercostals
define total lung capacity
maximum volume of gas the lungs can hold
define volumes
distinct, non-overlapping sub-compartments referred to as lung volumes
define tidal volume
500 ml
volume of air that is inspired or expired with each breath at rest
define inspiratory reserve volume
3000 ml
volume of air that can be inspired in addition to tidal volume with forceful inspiration
define expiratory reserve volume
1100ml
additional volume of air that can be expired at end of tidal volume by forceful expiration
define residual volume
1200 ml
volume of air remaining in lungs after forceful expiration
define vital capacity
4600 ml
sum of all the volumes that can be inspired or exhaled
inspiration to the max extent plus expiration to the max extent
define total lung capacity
5800 ml
the sum of all the volumes= vital capacity plus residual volume
define inspiratory capacity
3500 ml
the sum of volumes above resting capacity= tidal volume plus inspiratory reserve volume
define functional residual capacity
2300 ml
the sum of volumes below resting capacity= expiratory reserve volume + residual volume
define minute ventilation
total volume of gases moved into or out of the lungs per minute
define alveolar ventilation
total volume of gases that enter spaces participating in gas exchange per minute
what is found in the anatomical dead space
trachea, bronchi, bronchioles
what is found in the physiological dead space
anatomical dead space + ventilated alveoli with poor or absent perfusion
what is the total dead space in a normal person
0.15 liters
what is the normal tidal volume
0.35 liters
what does the amount of CO2 in regions of lungs involved in gas exchange equal
that of arterial blood
define pleural pressure
pressure of the fluid between parietal pleura and the visceral pleura
define alveolar pressure
pressure of the air inside of the alveoli
define transpulmonary pressure
difference between the alveolar pressure and the pleural pressure
how is pleural pressure measured
measured in centimeters of water
what is pleural pressure during inspiration and expiration
inspiration: -5 to -7.5 cm H2O
expiration: -7.5 to -5 cm H2O
define compliance
the extent (volume) to which lungs will expand for each unit increase in the transpulmonary pressure
what is normal compliance
200 ml air per cm of water
define compliance in terms of the trachea
measure of the expansibility of the lungs and trachea
what are the elastic forces of the lungs depicted in the compliance diagram
elastic forces of lung tissue
surface tension within the alveoli
what happens when there is an absence of surface tension forces
ease with which lungs can be expanded
define elastance
measure of the tendency of a hollow viscus to recoil toward its original dimensions upon removal of a distending or collapsing force
what are the most important components of surfactant
dipalmitoylphosphatidylcholine (a phospholipid)
surfactant apoproteins
calcium ions
what produces surfactant
type 2 alveolar cells
what happens if air passages leading from the alveoli are blocked, the surface tension in the alveoli collapses the alveoli?
positive pressure is created in the alveoli
what happens to the pressure in the alveoli as the radius increases
pressure decreases
