Anatomy and Physiology of the Lungs Flashcards
What is the function of respiratory system?
- Gaseous exchange
- Acid-Base balance
- Phonation
- Pulmonary defence mechanism
- Pulmonary metabolism
What makes the respiratory system?
- Upper respiratory
- Lower respiratory
- Lateral surface of lungs
What components are in the upper respiratory?
- Frontal sinus
- Nasal cavity
- Nasal conchae
- Tongue
- Nose
- Sphenoidal sinus
- Internal nares
- Pharynx
- Thyroid bond
What components are in the lower respiratory?
- Esophagues
- Trachea
- Bronchus
- Bronchioles
- Clavicle
- Ribs
- Diaphragm
- Lungs (right and left)
- Alveoli
What are the components in the lateral surface of the lungs?
- Apex
- Superior lobe
- Middle lob
- Inferior lobe
- Horizontal fissure
- Cardiac notch
- Oblique fissure
- base
Does the left lung point towards or sit on the heart?
Point towards
What is the difference between the right and the left lung?
The left has a cardiac notch and no middle lobe
What two functional zones can the airway be split in?
- Conduction zone
- Respiratory zone
Describe the conducting zone:
- First 16 generations (i.e. divisions or splits) incapable of gaseous exchange
- No alveolar present
Describe the respiratory zone:
- Alveoli present between generation 17-23
- Gaseous exchange
What components are in the conducting zone?
- trachea
- Bronchi
- bronchioles
- terminal bronchioles
How many tubes are in the trachea region?
1
How many tubes are in the bronchi region?
2
How many tubes are in the bronchioles region?
4
How many tubes are in the bronchioles region?
8 - 32
How many tubes are in the terminal bronchioles region?
6 x 10^4
What components are in the respiratory zone?
- Respiratory bronchioles
- Alveolare duct
- Alveolar sacs
How many tubes are in the respiratory bronchioles region?
5 x 10^5
How many tubes are in the alveolar sacs region?
8 x 10^6
What is involved in muscles of respiration?
- Diaphragm
- Intercostals
- Accessory muscles
Describe the diaphragm:
- Most powerful
- 1/3 to 1/2 of tidal volume
Out of the diaphragm, intercostals and accessory muscles which is the least powerful??
-Intercostals
Where do you fine must accessory muscles?
-Neck muscles
When is accessory muscles used?
Extreme distress
When is the abdominal wall muscles used?
In forced expiration
Are respiratory muscles smooth or skeletal muscles?
Skeletal
Are the intercostal muscles between the ribs or not?
Its is
What different types of intercostal muscles?
- External intercostal muscles
- Internal intercostal muscles
- Innermost intercostal muscles
What is respiratory air flow determined by?
The pressure difference between the mouth and alveoli
What are the two different types of respiratory flows?
- Upstream rise in pressure
- Down stream fall in pressure
How is inspiration caused relating to pressure?
Atmospheric pressure (ATM) is higher than ATM in lungs -Pressure gradient
How is expiration caused relating to pressure?
Increase pressure inside lungs than outside
-Pressure gradient
What does Patm stand for?
Atmosphere pressure
What does Pip stand for?
Intrapleural pressure
What does Ptp strand for?
Transpulmonary pressure
What does Palv stand for?
Alveolar pressure
Why is Pip already negative?
Due to counter recoil of chest wall and alveoli
Describe inspiration:
- Inspiratory muscles contract
- Pip becomes more negative
- Increases difference Palv and Pip which increases Ptp
- Increases difference between Palv and Pip
- Alveolar volume increases
- Palv decreases
- Change in pressure between atm and all
What is important to remember about Ptp?
The larger the Ptp the greater the alveolar wall distension
Describe expiration:
- Inspiratory muscles relax
- Pip becomes less negative
- Decreases difference between Palv and Pip which decreases Ptp
- Alveolar volume decreases
- Palv increases
- Change between all and atm
What happens if Ptp is smaller?
The alveolar walls recoils
What is alveolar interdependence?
Outer alveoli are affected by the change in the intrapleural pressure which affects the next alveoli and so on until inner depths of lungs
Increasing space without changing the inside volume will decrease the pressure
What law does this represent?
Boyles’ Law
What is intraplueral space?
- Fluid
- Allows lubrication due to two moving parts
- Water tension (the riser pleura will follow the parietal pleura when it moves)
What is the pneumothorax?
When air gets into the space between the outside of your lung and the inside of your chest wall, your ribcage.
How can pneumothorax happen?
Pleural seal broken wither by:
-Inwards through the lung tissue
OR
-Outwards through the chest wall
What happens if you have pneumothorax?
- Negative pressure cannot not be generated - ventilation ineffective
- Lungs collapse due to unopposed elastic recoil of alveoli
What are the two factors need to overcome for work of breathing?
- Resistance
- Compliance
How is resistance relevant to work of breathing?
- Resistance of respiratory tract to airflow during inspiration and expiration
- Affected by diameter of airway
How is compliance relevant to work of breathing?
-Measures of the lungs ability to stretch and expand
What is dispensability of elastic tissue?
Measures of the lungs ability to stretch and expand
What happens to breathing with increase resistance?
- Obstructive diseases
- Airway narrowing (e.g asthma)
- Increasing respiratory rate
Why are children at a greater risk of resistance?
- Smaller airways
- Higher resting respiratory rates
What happens to breathing with decrease compliance?
- Restrictive disease
- Affects expandability of lungs (and chest wall)
- Value varies as lungs inflates
Is fibrosis the caused by high compliance or low compliance?
Low compliance
Is emphysema the caused by high compliance or low compliance?
High compliance
Does compliance or resistance lead to restrictive diseases?
Compliance
Does compliance or resistance lead to obstructive diseases?
Resistance
