Pulm. 1 & 2 Flashcards
What is the main function of the respiratory system? (other functions?)
gas exchange
-barrier function
-metabolic
host defense
what is the barrier function of resp. system?
mucocilliary clearance
What is the metabolic function of the resp. system?
angiotensin I, serotonin
what is the host defense of the rest. system?
immune functions
What are the steps of respiration?
- Exchange air in the lungs
- Exchange O2 & CO2 in the alveoli
- O2 & CO2 are transported in blood
- O2 & CO2 are exchanged in the cells
- Mitochondria consume O2 and produce CO2
Upper airway structures
Nose
Pharynx
Glottis
Vocal Cords
Lower airway structures
Trachea
Bronchial tree
Alveoli
Function of upper airway
- filter
- warm
- humidify air
How many lobes does the right lung have?
3 lobes
- oblique
- horizontal
What is the Functional Anatomic Unit of a lung?
bronchopulmonary segment
What is the basic Physiological Unit of a lung?
respiratory unit
- respiratory bronchioles
- alveoli
Effects of surface tension
- resists being stretch
- tends to reduce surface area
- creates tendency to recoil after stretch
Where do bronchial veins lead?
- 1/3 blood returns to the right heart
- 2/3 drains into pulmonary circulation
Bronchial arteries
- from aorta to terminal branches
- merges with pulmonary arteries and capillaries
- 1-2% of cardiac output
Deposition of inhaled particles
- Impaction in nasopharynx
- Sedimentation in small airways
- Diffusion in alveoli
Components of mucociliary clearance system
- mucus layer
- periciliary fluid
- cilia
Volume of anatomical dead space
150 mL
Volume of respiratory region
2.5 L - 3.5 L
surface area: 50 - 100 m2
What stabilizes alveoli?
- Surfuctant
- Interdependence
What are the major muscles of inspiration?
- Diaphragm
- External intercostal muscles
What are the muscles of active expiration?
- Internal intercostal muscles
- Abdominal muscles
What are the accessory muscles and what are they used for?
- forced inspiration
- scalene
- sternocleidomastoid
What does the spirometer fail to measure?
- residual volume
- functional residual capacity
- total lung capacity
Lung Volumes
- Tidal Volume
- Inspiratory Reserve Volume
- Expiratory Reserve Volume
- Residual Volume
Tidal Volume
Change in volume that occurs with cyclic breathing
Inspiratory/Expiratory Reserve Volume
volumes that can be in/exhaled in addition to the tidal volume (ex.) during forced inspiration/expiration
Residual Volume
the volume that remains in the lung even after forced expiration
Inspiratory Capacity (Lung Volumes)
Inspiratory Reserve Volume + Tidal Volume
Functional Residual Capacity (Lung Volumes)
Expiratory reserve volume + Residual volume
Vital Capacity (Lung Volumes)
Inspiratory / Expiratory reserve volume + Tidal Volume
Total Lung Capacity( Lung Volumes)
Inspiratory / Expiratory reserve volume + Tidal Volume + Residual Volume
Vital Capacity
the amount of air that can be moved from deep inspiration to deep expiration
Function Residual Capacity
the volume of air in the lungs when all respiratory muscles are relaxed
Inspiratory Capacity
The volume of air that can be inhaled after all respiratory muscles are relaxed (starting at FRC)
Total Lung Capacity
total volume of air held by the lung. TLC includes alveolar and dead space volume and is scaled to the size of the person
Forces that inflation must overcome
- viscoelastic properties of the lung parenchyma by stretching elastic and collagen fiber matrices
- surface tension forces set up between air/water interface on the alveolar epithelium
Tidal Volume (the value)
500 mL
Inspiratory Reserve Volume (the value)
3000 mL
Expiratory Reserve Volume (the value)
1200 mL
Residual Volume (the value)
1200 mL
