Nasal Cavity Function + Intro Flashcards
What drives O2 across alveolar membrane
Partial pressure
Is the pressure higher or lower at higher altitudes
P is lower
Arterial content of O2 is lower
Hb conc increases
what does Qº mean
Blood flow OVER TIME
What are the conducting zone airways
Trachea -> terminal bronchioles
1st 16 generations
What are the transitional/respiratory zone airways
Resp bronchioles -> alveolar sacs
Last 7 generations
Functions of conducting zone
Heating, humidifying and filtering inspired air
delivery of air
upper airway resistance
NO GAS EXCHANGE OCCURS IN CONDUCTING ZONE
Effect of O2 equilibrium on gas exchange
DOES NOT STOP gas exchange
What travels into and out of alveoli (non-ciliated)
Macrophages - remove particles by lymphatics and blood flow
What pressure pushes fluid into alveoli
Hydrostatic pressure
What pressure pushes fluid out of alveoli
Oncotic pressure
Effect of fluid filled alveoli on gas exchange
No gas exchange due to decrease in oncotic P
When does a baby produce surfactant
@ 28 weeks
Non-pulmonary functions of respiratory system
- Control of pH in EC fluid - blood and ISF
pH => CO2 and bicarbonate
pH = 6.1 + log10 ([HCO3-]/0.03 x pCO2)
- Behavioural - phonation
- Defense - humidifcation, IGs, Lysozymes, complement system
4 consequences of infection
- Granuloma formation
- Phagocytosis of bacilli - NO production
- Increase in IL-10 (anti-inflammatory) and TNF-alpha (WBCs)
- TLR 2/3 (recognises 2x stranded DNA)/4 - recognise patterns on microbes
4 consequences of asthma
- DC activation
- Increase in M2
- IL-10
- Chemokines - eosinophils, basophils
3 consequences of COPD
Impaired TLR2
Impaired phagocytes
Increase in IL-8, TNF-alpha, ROS
6 ways normal macrophage function could be impaired
- Inhaled gases - ozone, cigarette smoke
- Toxic particles e.g. silica
- Alveolar hypoxia
- Radiation
- Corticosteroids
- Alcohol ingestion
How are small particles lodged in conducting airways removed
What happens if there are no Cl- ions secreted
- A stream of mucus propelled by ciliary action, moving them upwards towards epiglottis to be swallowed
- Mucus does not move and traps microbes in respiratory tract => persistent infections
CF - type of disorder
what is it a mutation of
Autosomal recessive heterogneous genetic disorder
Mutation of CF transmembrane conductance regulator (CFTR) - chromosome 7
What is the CFTR protein
where is it found
cAMP regulated Cl- channel
Regulates other ion channels
=> those with CF have salty sweat
found in plasma membrane of epithelial cells
Pathophysiology of CF
- Increase in trans-epithelial electric PD
- Inhibits cAMP-dependent kinase and PKC-regulated Cl- transport
- Increase in Na+ transport, decrease in Cl- transport
- Decreased salt and water content in mucus
- Depeletes peri-ciliary liquid
- Mucus adheres to airways => decreased mucus clearing
- Pre-disposition to staph and pseudomonas infections