Respiratory system Flashcards
What is expiratory capacity?
This is the maximum amount of air that you are able to breathe out of your lungs
EC= Tidal volume expiratory +ERV
What is Air flow = to?
Flow = Patm -Palv /R
What is the respiratory membrane?
It is the layers that the air has to pass through to get to the blood
Epithelial cell membranes (x2)
Basement membrane
Blood capillary membranes (x2)
How many secondary bronchioles are on the right side?
3 secondary bronchi serve the 3 lobes of the right side
Right has Trinity
How does histamine cause bronchoconstriction?
Histamine is an inflammatory chemical released locally that will trigger the smooth muscle to constrict to prevent the allergen from entering the body
In the end it also makes breathing difficult by decreasing airway size, increased mucus production and overall increased resistance
What are the air passages from pharynx to lungs?
Larynx
Conducting zone
Respiratory zone
What is forced vital capacity?
The maximum volume inhaled followed by exhalation as fast as possible
What is FEV1 ?
% of FVC that can be exhaled within 1 second
What is transpulmonary pressure?
Transpulmonary pressure= Palv -Pip
This is the pressure that determines whether the lung expands or not.
Negative = collapse (pressure pushes against lung)
Positive= expand (pressure is lower than inside lung)
What are the air passages of the head and neck?
- Nasal cavities
- Oral cavities
- Pharynx
What drives the movement of air into and out of the lungs?
Pressure gradients cause air to move from areas of high pressure to low pressure
When does inspiration occur?
Pressure in the lungs is less than atmospheric pressure so air moves from high (outside) to low (inside)
Why is the residual volume of air in the lungs important?
This volume of air prevents the lungs from collapsing
What 3 factors affect compliance normally?
- Elasticity of lungs
- Surface tension
- Elasticity of chest wall
What is the difference between internal respiration and external respiration?
- Internal respiration refers to oxidative phosphorylation
External respiration refers to
Pulmonary ventilation (bringing air in and out)
* Exchange between lungs and blood
* Transport in blood
* Exchange between blood and body tissues
How does CO2 affect the size of bronchioles?
⇑⇑⇑CO2 LEVELS
Metabolic rate is increasing so gas exchange needs to increase to meet the demand
Airways will bronchodilate to increase the amount of air entering the lungs
Blood flow will also increase to increase gas exchange rate
What is the Residual volume (RV)?
1200ml
This is the amount of air that remains in the lungs to keep the alveoli open even after the maximum amount of air is expired from the lungs
What effect does obstructive lung disease have on volumes and capacities?
Expiration Reserve Volume decreases
Residual volume increases
Total lung capacity increases
Vital capacity decreases (ERV⇣)
How does elasticity affect compliance?
The lungs can easily expand but they also want to recoil to expire
If the lungs have a lot of scar tissue (fibrous) they will not be able to stretch as much decreasing compliance, but increasing elasticity in that the lungs want to snap back once expanded.
If the elastin in the lungs decreases in emphysema the lungs will be compliant in stretching and taking a lot of air in, but it will not be able to recoil/ snap back to expire resulting in the air staying in the lungs => Barrel chest
What is Boyle’s law?
Pressure is inversely related to volume
How does epinephrine affect the airway resistance?
Epinepherine will bind to beta receptors in the airways and trigger them to bronchodilate
Relaxation of smooth muscle
What is the Vital capacity (VC)?
This is the amount of air that you can bring in during normal inspiration and expiration and forceful inspiration and expiration.
VC= TV+ ERV+IRV
How does COPD affect airway resistance?
Increases the airway resistance on a long term basis
Emphysema leads to destruction of alveoli leading to destruction of the respiratory zone
Loss of airway elasticity
How does bronchoconstriction affect the airway resistance?
The smooth muscle surrounding the airways constrict decreasing the size of the airway lumen.
As the Area decreases the resistance increases and the flow of air becomes harder
What is a pneumothorax and why does it make it hard to breathe?
Pneumothorax is the presence of ATMOSPHERIC AIR within the pleural space which increases the pressure placed against the lung.
Increasing intrapleural pressure makes the transpulmonary pressure negative causing the lung to collapse
What is the tidal volume?
500ml
The amount of air we breathe in unforced in a single breath (inspiration & expiration)
(like when we are not thinking about it)
What factors determine intra-alveolar pressure?
Quantity of air in the alveoli
Volume of alveoli
How is the resistance to the air flow in the lung kept relatively constant?
Conducting zone bronchi have a large diameter
Total cross sectional area of bronchioles is huge as the vessels get smaller they increase in number
What is the minute respiratory volume?
Total amount of air that flows in or out of the respiratory system in 1 minute
What is inspiratory capacity (IC)?
This is the maximum amount of air that you can bring into the lungs
IC= Tidal volume inspiratory + IRV
What is surface tension?
- This is where water molecules on the surface of the water experience a net inward pull by neighboring/ deeper water molecules causing them to move closer together forming a film (become more compacted)
- Some may be pulled from the surface creating a vacuum that remaining molecules are attracted to creating surface tension.
- As the molecules move closer together to fill in the gaps this surface area decreases
- Air-water interface tries to have the least surface tension in general
Where do cartilage rings stop in the lungs?
Smaller bronchi are the last bronchi after tertiary to have cartilage plates
Bronchioles and terminal bronchioles do not have cartilage