Pathophysiology

1. Denver School of Nursing – ADN & BSN Programs No Laboratory component for this class Pathophysiology BIO 206 & 308 – Ch 25 & 26 – Pulmonary Phys / Path

2. The Respiratory System What are the three most important structures of the Respiratory System???

3. The Respiratory System What are the three most important structures of the Respiratory System??? 1. Lungs – WHY? 2. Muscles of Respiration – WHY? 3. Brain – WHY?

4. The Respiratory System

5. The Respiratory System Primary = Secondary = Tertiary= Muy Importante!=

6. The Respiratory System

7. The Respiratory System • The Respiratory System is divided into two general parts: • The Upper Respiratory Tract • The Lower Respiratory Tract Where do you think the division starts?

8. The Respiratory System

9. The Respiratory Mucosa • What is the respiratory mucosa?

10. The Respiratory Mucosa Proper Definition: • From A&P Thibodeau: “Mucous membranes are epithelial membranes that line body surfaces opening directly to the exterior (latin name, mucosa)... Their name is derived from the fact that they produce a film of mucus that coats and protects the underlying cells.” • In addition to protection, the mucus has other purposes, can you tell me what they are??

11. The Respiratory Mucosa Function of Mucosa: • Protection – for underlying tissue • Immune Support! • Mechanically capture debris • Presence of “mucins” (proteoglycans) • Bacterial interface • Lubricant – to allow food to move in digestive tract, and if aspiration occurs in respiratory tract the mucosa will also allow for the pleasantry of “regurg” / emesis.

12. Primary Features of the RS • Nose • Pharynx • Larynx • Trachea • Bronchi • Bronchioles • Alveoli • Lungs • Pleura What is the purpose and function of each of these structures???

13. The NOSE

14. Pharynx

15. Larynx – aka the “Voice box”

16. Larynx

17. Larynx

18. Trachea

19. Brochi Remember what these are REALLY called?

20. Brochi Bronchioles 

21. Alveoli

22. LUNGS (3 lobes on 3, 2 Lobes on Left)

23. Serous Membranes • What are the serious membranes in the body?

24. Serous Membranes Image from http://www.augustatech.edu/anatomy

25. Serous Membranes • Where are the 3 primary serous membranes found in the human body? Image from http://www.augustatech.edu/anatomy

26. Digestive System • Serous membranes: Heart, lungs, GI Image from http://www.augustatech.edu/anatomy

27. Plura

28. How Does Breathing Work?? Illustration of the mechanism of respiration

29. Mechanics of Breathing • Major and accessory muscles • Major muscles of inspiration • Diaphragm • External intercostals • Accessory muscles of inspiration • Sternocleidomastoid and scalene muscles • Accessory muscles of expiration • Abdominal and internal intercostal muscles

30. Muscles O’ Ventilation

31. Mechanics of Breathing • Alveolar surface tension and ventilation • Function of surfactant • Elastic properties of the lung and chest wall • Elastic recoil • Compliance • Airway resistance • Work of breathing

32. Gas Transport • Four steps • Ventilation of the lungs • Diffusion of oxygen from the alveoli into the capillary blood • Perfusion of systemic capillaries with oxygenated blood • Diffusion of oxygen from systemic capillaries into the cells • Diffusion of CO2 occurs in reverse order

33. How does it really work? • IN the PONS (of the Brain Stem) 1) Apneustic Center Stimulates neurons to promote Inspiration via External intercostals and the diaphragm 2) Pneumotaxic Center Stimulated neurons to promote Expiration via the Internal intercostals and rectus abdominis

34. Ventilation • Neurochemical control • Respiratory center • Dorsal respiratory group • Ventral respiratory group • Pneumotaxic center • Apneustic center

35. How does it really work? • Chemoreceptors 1) Central Chemoreceptors ~ located in the medulla 2) Peripheral Chemoreceptors ~ located in the Aorta & the carotid bodies Both detect increased levels in Carbon Dioxide, and then stimulate Increase in RR

36. Function of the Pulmonary Sys • Ventilate the alveoli • Diffuse gases into and out of the blood • Perfuse the lungs so the body receives oxygen

37. Function of the Pulmonary Sys • Ventilation • Mechanical movement of gas or air into and out of the lungs • Minute volume • Ventilatory rate multiplied by the volume of air per breath • Alveolar ventilation

38. White Board Sesh… • Lung Volume chart

39. White Board Sess… Image Source: http://www.anaesthetist.com

40. Tests of Pulmonary Function • Spirometry • Diffusion capacity • Residual volume • Functional reserve capacity (FRC) • Total lung capacity • Arterial blood gas analysis • Chest radiographs

41. Pulmonary System • Conducting airways • Upper airways • Nasopharynx • Oropharynx • Larynx • Connects upper and lower airways • Lower airways • Trachea • Bronchi • Terminal bronchioles

42. Bronchioles-”respiratory tree”

43. Pulmonary Physiology • Gas-exchange airways • Respiratory bronchioles • Alveolar ducts • Alveoli • Epithelial cells • Type I alveolar cells • Alveolar structure • Where diffusion of Respiratory gasses occurs • Type II alveolar cells • Surfactant production

44. CO2 & O2 – alveolar exchange

45. Structures of the Pulmonary System

46. Pulmonary & Bronchial Circ. • Pulmonary circulation has a lower pressurethan the systemic circulation • One third of pulmonary vessels are filled with blood at any given time • Pulmonary artery divides and enters the lung at the hilus • Each bronchus and bronchiole has an accompanying artery or arteriole

47. Pulmonary & Bronchial Circ. • Alveolocapillarymembrane • Formed by the shared alveolar and capillary walls • Gas exchange occurs across this membrane • Membrane formed by what cells?

48. Pulmonary & Bronchial Circ.

49. Measurement of Gas Pressure • Barometric pressure • Partial pressure • Partial pressure of water vapor

50. Measurement of Gas Pressure