1. Take a Deep Breath –
Focus on the air-
Where is it going?
How does it move?
What purpose does
it serve?

2. Airway Defenses: Nose: Mucociliary clearance: Cough:
Reflexive bronchoconstriction:
Alveolar macrophages:

4. Ventilation
Inhalation Exhalation

5. Rate and volume control:
Respiratory control center in the brain stem
Responds to chemoreceptors
CO2, pH, O2 – all trigger responses
Which would cause what?

7. Work of Breathing Lung Compliance:
Ability of lung tissue and chest wall to expand
Surfactant – key facilitator
Chest injuries? What would they causes?

9. Work of Breathing Elastic recoil – Promotes expiration
Elastin fibers are present around the alveoli which act just like an elastic
Elastin fibers are damaged in patients with emphysema – leads to air trapping.
What does this do for ventilation? Diffusion?

10. Work of Breathing Increased Airway Resistance:
Asthma – results in bronchoconstriction, airway hyperreactivity, edema
COPD – (emphysema) Most common cause is smoking – chronic inflammation leads to loss of elastic recoil.
Cystic fibrosis – genetic – results in massive mucus production
What impact do these have on ventilation?

11. Measuring ventilation
Tidal volume
Vital capacity
Forced vital capacity
Forced expiratory volume – 1 sec
Residual volume
Total lung capacity

12. Impaired ventilation Something interferes with the movement of air
What might cause a narrowing or compression of the airways – anywhere along the way?
What about neuronal stimuli – how might it be a cause of problems?

13. Diffusion Where alveoli interact with vascular – one cell thick!
Diffusion – down the concentration gradient

14. Diffusion

15. Diffusion Enhanced by: Pressure – concentration gradient
Solubility of gases: CO2 more soluble = diffuses more easily
Distance from alveoli to capillary = super short
Surface area
What impact does accumulation of fluids have on the ability of gases to diffuse?
What condition result in fluid accumulations?

16. PaCO2 – PaO2 – HbO2/saO2
Gases consist of particles – when they get in the serum they move about – this creates a pressure.
How is this lab reported?
The body can use this oxygen – it diffuses –
Oxyhemoglobin = oxygen bound to hemoglobin
The body cannot use this oxygen –
Until it comes off the hemoglobin
Hemoglobin is the delivery truck

17. Impaired diffusion Pressure/Solubility: O2 pressure Increases w/
Increased barometric pressures
Temperature increases
So – when would this decrease?
High elevations
Hypothermia
Inadequate supply
Membranes:
Fluid or exudate = increased diffusion distance
Decrease in surface area
Fibrosis/thickening of either/both membranes

18. V/Q mismatch
Either ventilation (V) or Perfusion (Q) is not adequate to facilitate gas exchange.
No oxygen – but perfusion is present
No perfusion – but oxygen is present

19. Results of decrease vent/diffusion
Hypoxemia/hypoxia
What is the end result?
Brain is super sensitive – what will you see?
Hypercapnia
What PaCO2 values will you see?
What type of acid/base imbalance do you have?
What are some results of this?

20. Manifestation of impaired ventilation/diffusion
Cough
Excess mucus production
Hemoptysis
Dyspnea – subjective “patient reports…..”
Accessory muscles use - objective
Chest pain
Barrel chest
Adventitious breath sounds - objective

21. Systemic manifestations
Cyanosis – late sign!
ABG values
What does ____________ tell you?
PaCO2
PaO2
SaO2
Mental status – restless, irritable…..lethargy
Finger clubbing

22. Pneumonia What does this do for: Ventilation? Diffusion? Red vs gray
hepatization

23. COPD diseases Asthma, emphysema, chronic bronchitis

24. COPD diseases Asthma, emphysema, chronic bronchitis

26. COPD diseases Asthma, emphysema, chronic bronchitis

27. Acute respiratory distress syndrome

28. How does this impact ventilation/diffusion?
Chest trauma
Pneumothorax
How does this impact ventilation/diffusion?

29. How does this impact ventilation?
Chest trauma
Flail chest
How does this impact ventilation?

30. Next Week
Matters of the Heart