1. ST120 Concorde Career College, Portland
Respiratory System

2. Objectives Define the term respiration.
Describe the functions of the respiratory system.

3. Objectives
List and identify the structures of the respiratory system and describe the function of each.

4. Objectives Describe the process of respiration.
Describe the mechanism by which the respiratory system helps to maintain homeostasis.

5. Objectives
Describe common diseases, disorders, and conditions of the respiratory system including signs and symptoms, diagnosis, and available treatment options.
Demonstrate knowledge of medical terminology related to the respiratory system verbally and in the written form.

6. Respiration More than breathing in and out.
Process by which oxygen is obtained from the environment, delivered to the cells, and waste products such as carbon dioxide are removed from the body.

7. Terms
Respiration- Inhaling and exhaling facilitate the process of taking in oxygen and getting rid of waste CO2.
Internal respiration- exchange of O2 and CO2 between the blood and body cells.
External respiration- exchange of O2 and CO2 between the lungs and the circulatory system.
Cellular respiration- the use of O2 by the cells of the body & production of CO2.
Ventilation- movement of air in & out of the lungs (breathing)

8. Functions of the Respiratory System
Pulmonary ventilation
Inhalation
Exhalation
Diffusion of gases
Into and out of the blood
Transport to and from the cells (cellular respiration)
Oxygen
Carbon dioxide

9. Primary Structures of the Respiratory System
Nasal cavities
Pharynx
Larynx
Trachea
Lungs
Diaphragm

10. Upper Respiratory Tract
Nose-
Covered by skin and supported by bone and cartilage. Air enters through the external nares and coarse hairs line the internal part of the nares to act as filters.
Nasal Cavities
Separated by nasal septum. Lining is made of ciliated epithelium (nasal mucosa). Highly vascularized, which warms inhaled air.
Nasal conchae
Curved scroll-like bones
Superior, middle, and inferior turbinates

11. Nasal Cavities External nares (nostrils) Nasal Cavities Sinuses
Nasal septum
Conchae (turbinates)
Sinuses

13. Sinuses Maxillary, frontal, sphenoid, and ethmoid
Named for associated bones
Move mucus into nasal cavities
Make skull lighter in weight

14. Paranasal Sinuses (Anterior)

15. Paranasal Sinuses (Lateral)

16. Upper Respiratory Tract
Pharynx
Tubular structure
Posterior to oral & nasal cavities
Conducts air and food
Three sections:
Nasopharynx
Oropharynx
Laryngopharynx
Composed of muscle, lined with mucous membrane

17. Pharynx
Nasopharynx
Oropharynx
Laryngopharynx

18. Lower Respiratory Tract
Larynx
“voice box” contains vocal cords (2 short fibrous bands that stretch across the interior of the larynx)
The space between the vocal cords is called the glottis
Connects pharynx to trachea
Serves as part of the air passageway
Lined with mucous membrane
Composed of cartilaginous rings:
Thyroid
Adam’s apple = thyroid cartilage
Cricoid
Sellick’s maneuver

19. Lower Respiratory Tract
Larynx
During swallowing, larynx elevates & epiglottis closes over opening to prevent food from entering
Vocal cords-located on either side of glottis
Breathing- cords close over glottis.
Speaking- cords are stretched & exhaled air vibrates cords causing speech.

20. Larynx

21. Lower Respiratory Tract
Trachea
“wind pipe”
Extends from layrnx to carina
Composed of 20 C-shaped rings of hyaline cartilage.
Flexible, keep trachea continuously open.
Primary bronchi = right and left bronchus
Mediastinal space
Lined w/ resp. epithelium
Enter lung & continue to divide
AKA “bronchial tree”

22. Trachea & Bronchi

23. Respiratory System Bronchi
Trachea divides (bifurcates) into two primary bronchi
Secondary bronchi
Tertiary bronchi
Bronchioles

24. Lower Respiratory Tract
Bronchial Tree
Trachea
2 primary bronchi
Secondary branches
Segemental/tertiary bronchi
Bronchioles
Terminal bronchioles
Alveolar ducts
alveoli

25. Lower Respiratory Tract
Bronchioles
Simple epithelium
Lack cilia, goblet cells, & cartilage
Contain smooth muscle bundles-regulate diameter of lumen
Exchange of gases
Divide into alveolar ducts w/ alveoli surrounding each duct = alveolar ducts

26. Pleural Cavity
Pleura = covers the outer surface of lungs and the lining of the inner surface of the rib cage
Parietal pleura lines the walls of the thoracic cavity
Visceral pleura covers the lungs
Contains:
Lungs
Pleural membranes
divided into parietal pleura and visceral pleura
Pleural space- space between parietal & visceral pleura, contains serous fluid,

27. Pleural Cavity Lungs Spongy, elastic tissue Right-3 lobes Left-2 lobes
Conical shape
Layers-
External visceral pleura
Sub serous layer of areolar tissue
Parenchyma
Blood supply
Arterial: bronchial arteries, branch from thoracic aorta

28. Lungs

29. Respiratory System Alveoli
Located at the end of the terminal bronchioles
Tiny sacs surrounded by vascular capillaries
Gas (O2 and CO2) occurs in the alveoli

30. Pleural Cavity Alveoli Alveolar walls Primary functioning unit
Responsible for gas exchange
Alveolar walls
Squamous epithelial cells-type 1 pneumocytes
Each alveolus is surrounded by pulmonary capillaries
Consist of a single layer of endothelial cells
A thin, filmy layer of fluid that covers the alveoli to reduce surface tension forces and aid in the expansion of alveoli is called Pulmonary Surfactant

31. Alveoli

32. Cluster of Alveoli at the Terminal Bronchiole

33. Pleural Cavity Alveolar-capillary barrier Pneumocytes 3 layers Type 2
Between air in alveoli & blood in pulmonary capillaries
Pneumocytes
Type 2
round in shape
Contain
large nucleus
Lamellar bodies-contain phospholipids that release surfactant
One alveolar sac is made up of numerous alveoli pg. 293 A&P

34. Microscopic View of Alveolar Sac

35. Pleural Cavity Diaphragm Separates thoracic & abdominal cavity
Divided into:
Crura
Central tendon
Subdivided into 3 divisions-leaflets
Major openings
Aortic
Esophageal
Inferior vena cava
The diaphragm muscle flattens out when it contracts during inspiration
The diaphragm muscle returns to upward position during expiration

36. Pleural Cavity Diaphragm Blood supply Lymph nodes Branches of
internal thoracic arteries
Thoracic aorta
Inferior phrenic arteries
Lymph nodes
Located on superior surface
Receive drainage from liver & esophagogastric junction

37. Pleural Cavity Intercostal muscles Located between ribs Divided:
External intercostal muscles covered by intercostal fascia
Intercostal nerves innervate muscles
Primary structures responsible for movement during respiration.

38. Physiology of Respiration
Inhalation
Diaphragm contract
Intercostal muscles relax
Exhalation
Diaphragm relaxes
Intercostal muscles contract

40. Pulmonary and Systemic Circuits
Pulmonary circuit
From the heart to the lungs and back to the heart
Systemic circuit
From the heart to the tissues and back to the heart

41. External Respiration O2 diffuses from alveoli into blood
CO2 diffuses from blood to alveoli
Blood high in O2 returns to heart, pumped out by left ventricle through the aorta to the body
Exchange of gasses between the blood and the lungs by diffusion

42. Internal Respiration O2 diffuses from blood to body cells
CO2 diffuses from body cells to blood
Venous blood is low in O2 returns to right ventricle to lungs for reoxygenation.

44. Regulation of Respiratory System
Nervous system
Medulla
Responsible for inspiration & expiration
Pons
Regulates normal rhythm of breathing
Centers
apneustic center
Pneumotaxic center

45. Regulation of Respiratory System
Nervous System
Chemoreceptors
Located in medulla, aortic bodies & carotid bodies
Detect changes in pH & blood gas levels
Phrenic nerve stimulates the diaphragm

46. Respiratory Monitors Pulmonary volumes Tidal volume Minute ventilation
Inspiratory reserve volume
Expiratory reserve volume – amount of air that can be forcibly exhaled after expiring the total volume
Vital capacity – largest amount of air we can breathe out in one expiration
Residual volume
Total lung capacity
Forced expiratory volume

47. Conditions
Pulmonary edema-abnormal accumulation of fluid in extravascular spaces or alveoli
Pneumothorax-abnormal accumulation of air between the parietal & visceral pleura
Pneumonia- acute infection of lungs
Chronic Obstructive Pulmonary Disease (COPD)-chronic airway obstruction
Emphysema-abnormal, irreversible enlargement of the alveoli due to destruction of alveolar walls
Pleurisy-Inflammation of the pleura that causes pain when the membranes rub together

48. Empyema

50. Rhinorrhea

51. Why is a tracheotomy done?
Gain access to airway before blockage
Create an open airway for breathing

52. Tracheotomy

53. Tracheotomy

54. Thoracentesis

55. Pulmonary Lobectomy Excision of one or more lobes Performed to excise
benign lesions,
malignant and
metastatic malignant
lesions

56. Terms
Bronchoscopy – TB – Pulmonary edema – Pharyngitis – Pertussis – COPD – Hyperventilation – Inspiration – Medulla – Inhalation – Respiratory arrest – Pneumothorax – Infant Respiratory Distress Syndrome – Epyema – Rhinorrhea – Thoracentesis – Pneumonia – Emphysemia -