Flashcards in Pulmonary Deck (42):
What type of cells line the trachea?
pseudostratified ciliated columnar epithelium with goblet cells
Where is the uvula located?
within the nasopharynx
Where is the glottis located?
Within the larynx
What type of cells line the bronchi?
pseudostratified ciliated columnar epithelium, same that line the trachea
What makes up the tracheobronchial tree?
alveolar ducts and alveoli
What muscles are responsible for inspiration?
diaphragm, external intercostal muscles, sternomastoids, serratus anterior muscles, scalene muscles
What muscles are responsible for forceful expiration?
abdominal muscles and internal intercostals.
What muscle initiates inspiration by lifting upward on the sternum?
What muscles cause inspiration by lifting on most of the ribs?
Serratus anterior muscles(most ribs)
scalene ribs (first two ribs)
True or False. Expiration is passive at rest.
What is the name of the volume of air that is inspired or expired with each breath at rest?
What is the name of the volume of air that can be inspired in addition to tidal volume with forceful inspiration?
inspiratory reserve volume
What is the name of the volume of air that can be expired at the end of tidal volume by forceful expiration?
Expiratory reserve volume
What is the name of the volume of air remaining in lungs after forceful expiration?
What is vital capacity?
The sum of all the volumes that can be inspired or exhaled at max. Expiratory reserve volume +tidal volume + inspiratory reserve volume
What is the average vital capacity of a healthy individual?
What is the average expiratory reserve volume of a healthy individual?
What is the average residual volume of a healthy individual?
What is the average tidal volume in a healthy individual?
What is the average inspiratory reserve volume of a healthy individual?
What is the relationship between lung capacities and lung volumes?
Lung capacity is the max volume of gas the lungs can hold. The lung capacity is made up of nonoverlapping subcompartments referred to as lung volumes. The combinations of lung volumes form lung capacities
What is the minute ventilation and how is it calculated?
Total volume of gases moved into or out of the lungs per minute.
(Breaths per minute) x (tidal volume)
16breaths/min x 500mL /breath = 8000mL/min
What is alveolar ventilation and how do you calculate it?
Total volume of gases that enter spaces participating in gas exchange per minute.
(breaths per minute) x ( tidal volume-dead space)
16 breaths/minute x (500ml/breath -150 ml/breath) = 5600 mL/min
What is the average volume of dead space per breath?
What is the difference between anatomical dead space and physiological dead space?
anatomical dead space is where gas exchange does not occur because of their anatomical function (example: trachea, bronchi, bronchioles). The phsyiological dead space is the anatomic dead space + ventilated alveoli with poor or absent perfusion.
average dead space is 150mL/breath or .15 liters
What is visceral pleura?
The layer that covers the surface of the lungs
What is the peripheral pleura?
The surface lining the pulmonary cavity
What is pleural pressure?
Pressure of the fluid between parietal pleura and the visceral pleura
What is the alveolar pressure?
Pressure of the air inside the alveoli
What is the transpulmonary pressure?
difference between the alveolar pressure and the pleural pressure
As lung volume increases during inspiration, what is the effect on the pleural, alveolar pressure, and transpulmonary pressure?
The pleural pressure becomes more negative while the alveolar pressure drops below atmospheric pressure increasing the transpulmonary pressure. This creates a suction pulling air into the lungs
What is compliance of the lungs?
The extent (volume) to which lungs will expand for each unit increase in the transpulmonary pressure.
What is the equation for calculating the compliance of the lungs?
increase in volume/increase in pressure
because distensibility = Vinc/ P inc x Vorig
distensibility x Voriginal = V inc/Pinc
What two factors determine the curve of the compliance diagram of the lungs?
The elastic forces of lung tissue
surface tension within the alveoli
What happens to the compliance diagram when surfactant is replaced with saline?
The saline-filled lungs will inflate with too much ease diminishing the air-fluid interface. On the diagram the curves of inspiration and expiration are very similar and very little change in pleural pressure.
What is the difference between elastance and compliance?
Compliance is the volume change resulting form the application of a unit pressure differential between the inside and outside of the viscus.
Elastance is a measure of the tendency of a hollow viscus to recoil toward its original dimensions upon removal of a distending or collapsing force.
What effect does increasing surface tension have on the alveoli?
Increasing surface tension will attempt to collapse the alveoli
What are the most important components of surfactant?
dipalmitoylphophatidylcholin (a phospholipid)
What type of cells produce surfactant?
Type II alveolar cells
What is the average pressure of surface tension of the average sized alveolus?
4 cm of water pressure (3mmHg)
The average pressure of surface tension in an average sized alveolus is 4 cm of water or 3 mmHg. What effect would the lack of surfactant have on the pressure?
Without surfactant the pressure would increase to 18cm of water pressure; about 4.5 times as great.