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Question 6

Deposition pattern of inhaled particles in various airway generations
Total cross-sectional area versus airway generation
  1. Bronchial responsiveness: PC20 and PD20Assume that the flow at the level of the trachea is 500 milliliter per second, and that tracheal diameter is 2 cm.
    What is the gas speed in the trachea?
  2. Bronchial responsiveness: PC20 and PD20Now look at the bottom illustration. The vertical axis shows how surface area increases from the trachea to the smaller airways.
  3. Bronchial responsiveness: PC20 and PD20Estimate gas speed at the 10th generation.
    Also estimate gas speed at the alveolar level, say at generation 20.
  4. The top figure illustrates the deposition pattern of particles in the airways as a function of particle diameter.
    Deposition pattern of inhaled particles in airwaysPollen are larger than 10 µm, mostly between 20-50 µm.
    How far do they penetrate into the airways, where in the airway do they impact?
  5. Deposition pattern of inhaled particles in airwaysAssume that a particle has a diameter of 10 µm: how much more mass does it bring to the airway than a 1 µm particle?
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