1. Pulmonary PhysiologyCHAPTER 1Structure and Function
2. Primary functions of the lung Gas exchange Bring in O2Remove
CO2Maintain acid base statusFilter bloodBlood reservoirMetabolizes
some compounds
3. Blood-Gas Interface Ideal suited for gas exchange Large
surface area Thin surface the size of a tennis court-100 square
meters 0.3 micrometers (1/1,000,000)Diffusion (or movement of gas)
is proportional to surface area and inversely proportional to
thickness
4. Air Room air is 21% oxygen The partial pressure of oxygen in
inspired gas is calculated by multiplying the percent oxygen by
atmospheric pressure (after subtracting water vapor) This is a very
important equation. You will see it again. Po2=FiO2(760-47)
5. Example 0.5 x (760-47) = 356 mm Hg
6. Breathing Not all the air we breath in is used for gas
exchange The airways used to get air to the alveoli are the
conducting airways (figure 1-4 in text). This contributes to dead
space Any area of ventilated lung that is not perfused it dead
space
7. Blood Flow Pulmonary arterial blood pressure is very low Due
to low resistance of pulmonary circulation Normal pressure about 15
mmHgSystemic blood pressure is about 80 mm Hg
8. Structure and Function Normal CT
9. Structure and Function Interstitial lung disease
10. Structure and Function Food for thought How do other lung
diseases show how structure affects function?How is this
demonstrated radiographically?How is this demonstrated on blood
gases?