Ventilation and compliance Flashcards
Define tidal volume
the air displaced between inspiration and expiration (500ml)
Define the anatomical dead space
150 mL and is the volume of gas occupied by the conducting airways and this gas is not available for exchange.
Define the reserve volume
expiratory - maximum breathed out (3000ml > TV)
Inspiratory - maximum breathed in (1100ml > TV)
Basically vital capacity reached
Define residual volume
The volume of gas in the lungs at the end of a maximal expiration - air is always present in the lungs
Why is residual volume important
- stops alveoli collapsing, as a partially inflated alveoli is way more efficient and easier for alveoli to be fully inflated again
- constant air pressure allows gas exchange to constantly occur
Define Vital capacity
maximum air that can be expelled from the lungs after a maximum expiration following maximum inspiration
tidal volume + inspiratory reserve volume + expiratory reserve volume.
Define total lung capacity
tidal volume + inspiratory reserve volume + expiratory reserve volume.
Define Inspiratory Capacity
tidal volume + inspiratory reserve volume.
Define functional residual capacity
expiratory reserve volume + residual volume.
What does the functional residual capacity prevent
Lung collapsing
What does FEV1 stand for?
Forced Expired Volume in 1 second
What does FEV1:FVC stand for?
Fraction of Forced Vital Capacity expired in 1 second.
What are the two types of ventilation
pulmonary ventilation
alveolar ventilation
Define pulmonary ventilation
total air movement into/out of the lungs
Define alveolar ventilation
fresh air getting to alveoli, available for gas exchange
What percentage of air reaches the alveoli and why
70% as its tidal volume minus the dead space
How do you calculate the alveolar ventilation
The amount of air that reaches the alveoli times the respiratory rate
Define partial pressure
The pressure of a gas in a mixture of gases is equivalent to the percentage of that particular gas in the entire mixture multiplied by the pressure of the whole gaseous mixture
What affects partial pressure of oxygen and CO2
Hypo and hyper ventilation
What happens to the tidal volume when the respiratory rate increases
Decreases - hypoventilation
What remains the same no matter if you are hypo or hyper ventilating
total pulmonary ventilation - still going to inspire and expire the same out of air - 6000ml
Someone who is hyperventilating is the alveolar ventilation more or less than normal
The alveolar ventilation increases above normal
During hypoventilation what gas increases in partial pressure and what gas decreases in pressure
Oxygen levels decrease in partial pressure (therefore increasing volume)
CO2 levels increase in partial pressure
BASICALLLYYY , Someone chilling on a hammock is what and why?
Hyperventialting as is breathing in more oxygen
How does the air we breathe in differ from the air present in the alveoli
becomes saturated going down respiratory tract - due to water present
previous dead air is now present in the air mix
residual volume is also present in the air mix
If CO2 levels are high, what does that indicate
Your body is failing to expire properly
What informs your body to breathe and why
Your body is sensitive to CO2 levels, therefore this propels your body to ventilate and expire CO2 preventing a build up
When you exercise do you hyperventilate or hypoventilate and why?
You hyperventilate as although you are breathing in rapidly you are taking in deep breaths, therefore more air reaches the alveoli, increasing alveolar ventilation
What two units is partial pressure normal refer to
mmHg or kPa units
What pressure do all gas molecules exert and what effect does this have on partial pressure
they all exert the same pressure, therefore partial pressure increases with increasing gas
True or false
anatomical dead space mix with air in the alveoli
false
What is a measure of the volume in the conducting airways that isn’t arable for gas exchange
anatomical dead space
During hyperventilation what does the Oxygen levels rise to and what do the carbon levels fall too (ALVEOLAR VENTILATION)
120mmHg/16Kpa
20mmHg 2.67Kpa
During hypoventilation what does the Oxygen levels decrease to and what do the carbon levels increase too (ALVEOLAR VENTILATION)
30mmHg 4Kpa
100mmHg 13.3Kpa
What is normal alveolar ventilation partial pressure for oxygen and co2
oxygen - 100mmHg /13.3Kpa
co2- 40mmHg/5.3kPa
What is the conversion from mmHg to Kpa
1mmHg = 0.133kPa
