Ventilation and Diffusion Flashcards
How do you convert from mmHg to kPa?
mmHg x 0.133322
What is atmopheric pressure at sea level?
760mmHg
101.325kPa
What are the partial pressure of nitrogen, oxygen and carbon dioxide at normal atmopshier pressure?
Nitrogen = 593mmHg
Oxygen = 159mmHg
Carbon Dioxide = 0.29mmHg
What happens to partial pressure if atmopsheric pressure changes?
partial pressure changes?
Oxygen can be toxic at high levels. What can be used to replaced it?
trimix - nitrogen-oxygen-helium
Heliox - oxygen-helium
What is dalton’s law of partial pressure?
in a mixture of non-reacting gases, the total pressure exerted is equal to the sum of the partial pressures of the individual gases.
What is Henry’s Law?
when a mixture of gases is in contact with a lquid, each gas will dissolve in the liquid in proportion to its partial pressure
partial pressure = 10kPa vs 1kPa
x10 more gas will go into solution if its partial pressure is 10kPa compared to 1kPa
What occurs if the partial pressure in the liquid becomes greater than in the air?
gas will move out of the liquid
What does the abolsute level of gas dissolved in liquid also depend on?
solubility of the gas
Rate the gases in order of solubility at atmopsheric pressure
CO2 = most soluble
O2 = 1/20th as soluble
N2 = barely soluble
What occurs if a gas enters a chemical reaction?
the total amount of gas in the liquid is the amount of gas dissolved plus that chemically bound in solution
What is alveolar gas not?
atmopsheric air
How do the conudtcing passages of the respiratory system alter atmopsheric air?
humidify the air so it is warm and moistened
What is the water vapour pressure of warm and moistened air?
47mmHg
What is the partial pressure of alveolar gas?
760-47 = 713mmHg