Respiratory Function Flashcards
What are the functions of the nasal cavity?
cleans, warms, moistens air
How does cold air trigger asthma?
Breath through mouth > cold air to lungs > stim. bronchospasm
What is deglutition apnoea?
Can’t swallow + breath at same time
Describe the structure of the trachea
- Lumen kept open by 20c shaped hyaline cartilage
- Gaps between rings filled with trachealis = bundle of smooth muscle + fibro-elastic tissue
- Epithelium = pseudo-stratified columnar
Describe the structure of the bronchus
- Circular layer of smooth muscle
- Less cartilage - does not completely encircle lumen
- Epithelium = tall columnar + some goblet cells
Describe the structure of the bronchioles
- No cartilage but smooth muscle layer doesn’t completely encircle lumen
- Epithelium = ciliated columnar in larger bronchioles, non-ciliated in smaller
- No goblet cells but Clara cells = secrete surfactant
What is Kartagner syndrome?
Cilia loose ability to function = fluid retention = pathogens + infection
What is the pulmonary interstitium?
- Area of lung between alveolar epithelial + capillary endothelial basement membranes
- Parenchymal part = airways structure
- Centrilobular part = bronchioles structure
What does PS innervation of lung cause?
Bronchoconstriction
Vasodilation
Mucous gland + goblet cell secretion
What does sympathetic innervation of lung cause?
Bronchodilation
Vasoconstriction
Modulate cholinergic transmission
Describe inhalation
- External ICM contract
- Rib cage up + out
- Diaphragm contracts = flat
- Low pressure, air drawn in
Describe exhalation
- External ICM relax
- Rib cage down
- Diaphragm relaxes = dome
- Volume decreases, pressure increases, air forced out
Define total lung capacity
Vol at max inflation
Define tidal volume
Air in + out during quiet breathing
Describe functional residual capacity
Vol left at end expiratory position (normal breathing)
