Flashcards in Resp Deck (235)
What is boyles law?
Pressure is indirectly proportional to volume of a fixed amount of gas
What is charles's law, what units are required
Pressure is directly proportional to temperature
What is the universal gas law?
What is its significance to drs?
Boyles and charles combined
Pressure x volume = universal gas constant x temperature
Any testing done outside of the body will generate different results of pressure as temperature changes
What is daltons law?
Each gas exerts its own pressure as if no other gases were present which is the same fraction of the total mix pressure as the fraction of the volume the gas.
How can water interact with gasses?
Evaporation of water
Dissolving of gas
What effect does evaporation have on inhaled gasses?
Water evapourates creating a fixed saturated vapour pressure at a given temperature (6.28kPa in the body) this is always exerted no matter the total pressure so is proportionally more important if total pressure falls
What is the tension of a gas in water? What does it equal at equilibrium?
A measure of how readily a gas molecule will leave the liquid
How is the amount of gas in a liquid calculated?
Content = solubility x tension
What is the effect on gases binding to molecules within a liquid on amount and tension?
Tension remains the same but amount goes up
In blood plasma what is the oxygen tension, what amount is dissolved in plasma at that tension given oxygens low solubility? How much is carried in whole blood? Why?
13.3kPa gives a dissolved content of 0.13mmol/L
Total blood has 8.93mmol/L due to haemoglobin binding
If an abg shows a pO2 of 13.3 is the patient definitely adequately oxygenated?
No - there could be a haemoglobin deficiency - anaemia
What is the partial pressure of oxygen in the atmosphere? What about alveolar air? Why the drop?
Oxygen is being removed and co2 and h2o added
What is the order of the airways?
What causes the alteration in nostril side during breathing?
Swelling of the venous plexuses in the lamina propria
What is the laryngeal epithelium?
Psudostratified ciliated columnar epithelium with mucous glands for the most part
Stratified squamous covering the vocal ligaments and the vocalis muscle
What is the change in epithelium from trachea to alveoli?
Psuedostratified ciliated (trachea, proximal bronchi)
Simple columnar ciliated (distal bronchi, proximal bronchioles)
Simple cuboidal ciliated (terminal bronchioles)
What changes occur to the secretory cells in the lower airways? Where?
In terminal bronchioles goblet cells are replaced with clara cells. In respiratory bronchioles clara cells are the predominant cell type.
What are the replacement for goblet cells in the lower airway? What do they produce?
Surfactant lipoproteins to prevent walls adhering in expiration
Where is bronchiole smooth muscle found?
Between the lamina propria and submucosa
What keeps the small airways open during expiration?
Direct pull from elasticity from neighbouring alveoli
Air pressure from the lumen exceeding that of the pleura due to elastic recoil of the alveoli in forced expiration
How does mucus secretion differ from bronchi to bronchioles?
Bronchi - mucus from goblet cells and submucosal glands
Bronchioles - no submucosal glands and goblet cells replaced with clara cells distally
Where do alveoli arise in the airways?
What are the cell types in the alveoli? What do they do?
Type 1 pneumocyte - squamous type that provides. Gas exchange surface
Type 2 pneumocyte - cuboidal type that secretes surfactant
Where are the lungs by surface markings?
Apex 3cm above medial 1/3rd of pleural cavity
Nearly meet at mid sternal line at 2nd rib
Descend together to the 4th rib
Left moves to left sternal before descending to 6, right decends straight to 6
Both descend to 8 (pleura) / 6 (lung) at MCL
Both descend to 10 p 8 l at MAL
Both descend to 12 p 10 l at medial scapular boder
What are the two fissures of the right lung?
What are their surface markings?
Oblique T2 to 6th costal cartilage
Horizontal 4th rib at mid axillary line to anterior edge of lung
Where does the manubrium join the body of the sternum?
Sternal angle of louis at level of second costal cartilage
How are the ribs classified?
Which ribs are typical? What are landmarks on their structure?
Two articular facets on head to articulate with body of vertebra or spine and vertebra above (i.e. 3rd rib with T2 and T3)
One articular facet to articulate with the transverse process of the vertebra
An inferior costal groove for vessels and nerves
Which ribs only have one facet on their head?