A Training Session on the Respiratory System

1. Respiratory System
Respiratory System
& Linkus

2. Respiratory System
Contents
Anatomy
Physiology
Pathology
Phytopharmacology
Linkus

3. Respiratory System
Respiratory System
 Function & Breathing

4. Respiratory System
Function
 Supplies the body with oxygen
 Removal of carbon dioxide from body
 Filters inspired air
 Produces sound
 Contains receptors for smell
 Rids the body of some excess water
 Helps to regulate the heat
 Helps regulate blood pH

5. Respiratory System
Breathing
 Breathing or pulmonary ventilation consists
of two cyclic phases:
Inhalation also called inspiration
Draws gases into the lungs.
An active process that requires input of energy. The Diaphragm
contracts, moving downward and flattening when stimulated
Exhalation also called expiration
Forces gases out of the lungs.
A passive process where the elastic
diaphragm recoils and the lungs and
thoracic cage return to the normal size
and shape

6. Respiratory System
Respiratory Values
Groups of children Their ages Normal respiratory rates
Newborns and infants Up to 6 months old 30-60 breaths/min
Infants 6 to 12 months old 24-30 breaths/min
Toddlers and children 1 to 5 years old 20-30 breaths/min
Children 6 to 12 years 12-20 breaths/min
Adults 12 years + 12 breaths / min

7. Respiratory System
Lung Volumes
 Tidal Volume (TV)
Volume inspired or expired with normal breathing ≈500 ml
 Inspiratory Reserve Volume (IRV)
Maximum volume that can be inspired over the tidal
volume. Used during exercise/exertion ≈ 3100 ml
 Expiratory Reserve Volume (ERV)
Maximum volume that can be expired after tidal volume
≈ 1200 ml
 Residual volume (RV):
Volume that remains in the lungs after a maximal
expiration. It cannot be measured by spirometry≈1200 ml

8. Respiratory System
Lung Volumes & Capacities

9. Respiratory System
Gross Anatomy of the Lungs
 Each lung has a conical shape.
 Its concave base rests on the muscular diaphragm
 Its top region called the apex
 Both lungs are surrounded by thoracic wall and
supported by the rib cage
 Toward the midline, the lungs are
separated from each other by
the mediastinum.
 The rounded surface in contact
with the thoracic wall is called the
costal surface of the lung.

10. Respiratory System
Respiratory System
Parts of Respiratory Tracts

11. Respiratory System
Organization of the respiratory
system
 Upper Respiratory Tract
• Nose/Mouth
• Nasal Cavities
Lower Respiratory Tract
• Pharynx
•Lungs
• Epiglottis
•Bronchi
• Larynx
•Bronchioles
• Trachea
•Alveolar Sacs
•Alveoli
Supporting Organs
•Pleura
•Diaphragm

12. Respiratory System

13. Respiratory System
Conduction vs. Respiratory zones
 The conduction zone is
most of the tubing in the
lungs
 Consists of nasal
cavity to terminal
bronchioles
 The respiratory zone is
where gas is exchanged
 Consists of respiratory
bronchioles alveoli,
alveolar ducts, alveolar
sacs and alveoli

14. Respiratory System
Respiratory System
Upper Respiratory Tract
(URT)
• Nose/Mouth
• Nasal Cavities
• Pharynx
• Epiglottis
• Larynx
• Trachea

15. Respiratory System
URT- Nose and Mouth
o Brings air into the body
o Removes air from the body
o Moistens and warms entering air
o Nasal hairs filters and cleans
inspired air in nostrils
o Detects odors in the air stream
o Resonating chamber for speech

16. Respiratory System
Nose
 Rich supply of capillaries warm the inspired air
 Olfactory mucosa – mucous membrane that
contain smell receptors
 Respiratory mucosa – pseudo stratified ciliated
columnar epithelium containing goblet cells
secrete mucus which traps inhaled particles
 Lysozyme kills bacteria and lymphocytes
 IgA antibodies that protect against bacteria

17. Respiratory System
Nasal Cavity
 External nares
 opening to exterior
 Internal nares
 opening to pharynx
 Nasal conchae
 folds in the mucous
membrane that ensures
that most air touches the
mucous membranes
 Sticky mucus line in
the nasal cavity
Traps dust, pollen etc that
were not trapped by nasal hairs
Cilia sweep mucus and trapped material to the back of the
throat

18. Respiratory System
Mucus movement

19. Respiratory System
Paranasal Sinuses
 Four bones of the skull contain paired air spaces called
the paranasal sinuses called Frontal, Ethmoidal,
Sphenoidal, Maxillary.
• They:
• Decrease skull bone weight
• Warm, moisten & filter incoming air
• Add resonance to voice
• Communicate with the
• nasal cavity by ducts.
• Lined by pseudostratified
ciliated columnar epithelium

20. Respiratory System
Pharynx
Major functions:
Tube-like passageway used by food, liquid, and air
 Common part of respiratory & digestive tract
 Walls are lined by a mucosa and contain skeletal
muscles that are primarily used
for swallowing
 Flexible lateral walls are
distensible in order to force
swallowed food into the
esophagus.

21. Respiratory System
Pharynx
 Partitioned into three adjoining regions:
 Nasopharynx- Upper most part of Pharynx connecting
nasal to pharynx. Passageway of air between nose &
larynx
 Oropharynx- Middle part of Pharynx.
Connecting the mouth to Pharynx
 Laryngopharynx- Part of Pharynx
where the common pathway divides
into Respiratory and Digestive.
Pharynx continues as Esophagus
and Larynx goes into the lungs.

22. Respiratory System
Nasopharynx
 Superior-most region of the pharynx.
 Located directly posterior to the nasal cavity
 Normally, only air passes through
 Material from the oral cavity is blocked from entering
the Nasopharynx by the uvula, which rises when we
swallow
 Auditory(Eustachian tubes) connect the Nasopharynx
to the middle ear.
 Posterior Nasopharynx wall also houses a single
pharyngeal tonsil called the adenoids.

23. Respiratory System
Oropharynx
 The middle pharyngeal region
 Immediately posterior to the oral cavity
 Bounded by the edge of the soft palate superiorly and
the hyoid bone inferiorly.
 Common respiratory and digestive pathway through
which both air and swallowed food and drink pass
 Lymphatic organs here provide the first line of defense
against ingested or inhaled foreign materials. Palatine
tonsils are on the lateral wall between the arches, and
the lingual tonsils are at the base of the tongue.

24. Respiratory System
Laryngopharynx
 Inferior, narrowed region of the pharynx
 Extends inferiorly from the hyoid bone to the larynx
and esophagus
 Terminates at the superior border of the esophagus and
the epiglottis of the larynx
 Permits passage of both food and air.

25. Respiratory System
Epiglottis
At the lower end of the pharynx is a flap of tissue called
the Epiglottis
Covers the trachea during swallowing so that food does
not enter the lungs
When breathing, it lies completely within the pharynx.
When one is swallowing it serves as
part of the anterior of the larynx.
The small structures on the upper surface
of epiglottis has taste buds

26. Respiratory System
Larynx
 Also known as the Voice box, containing the vocal
cords.
 Prevents swallowed materials from entering the lower
respiratory tract
 In sound production by opening and closing.
 Protesting the trachea against food aspiration
 The airway to which two pairs of
horizontal folds of tissue, called
vocal cords, are attached.

27. Respiratory System
Voice box in action

28. Respiratory System
Larynx

29. Respiratory System
Trachea
 Air-conducting tube to and from lungs
 Connects the larynx with the bronchi
 Lined with mucous membranes and cilia
 Contains strong cartilage rings
 At the level of the sternal angles,
the trachea bifurcates into two smaller
tubes, called the primary bronchi.
 Each primary bronchus projects
laterally toward each lung.
 The most inferior tracheal cartilage separates the
primary bronchi at their origin and forms an internal
ridge called the carina.

30. Respiratory System
Respiratory System
Lower Respiratory Tract
(LRT)
• Lungs
• Bronchi
• Bronchioles
• Alveoli
• Alveolar Sacs

31. Respiratory System
Lungs Structure
Right Lung 3 lobes Left Lung 2 lobes

32. Respiratory System
Lungs
Left lung
 divided into 2 lobes by oblique fissure
 smaller than the right lung
 cardiac notch accommodates the heart
Right lung
 divided into 3 lobes by oblique and horizontal fissure
 located more superiorly in the body due to liver on right
side
 Conducting airways (trachea, bronchi, up to terminal
bronchioles).
 Respiratory portion of the respiratory system
(respiratory bronchioles, alveolar ducts, and alveoli).

33. Respiratory System
Structure: Bronchi

34. Respiratory System
Bronchial tree
 A highly branched system of air-conducting passages
originating from the left and right primary bronchi
 Progressively branch into narrower tubes the secondary
and then the tertiary branches
 Incomplete rings of hyaline cartilage support the
walls of the primary bronchi to ensure that they remain
open
 Right primary bronchus is shorter, wider, and more
vertically oriented than the left primary bronchus.
 Foreign particles are more likely to lodge in the right
primary bronchus.

35. Respiratory System
Bronchial Tree
 Secondary bronchi tertiary bronchi
bronchioles terminal bronchioles
 With successive branching amount of cartilage
decreases and amount of smooth muscle increases.
 Opening of passage way stimulated by either
epinephrine or sympathetic nerves to increase air flow
 Bronchodilation
 Closing of passage way stimulated by Histamine,
parasympathetic nerves, cold air, chemical irritants and
other factors to decrease air flow
 Bronchoconstriction

36. Respiratory System
Bronchioles
 Tiny branches of air tubes in the lungs
 Connect bronchi to alveoli
 Epithelium gradually changes from ciliated
pseudostratified columnar epithelium to simple
cuboidal epithelium in terminal bronchioles

37. Respiratory System
Respiratory Bronchioles, Alveolar
Ducts, and Alveoli
 Small saccular out-pocketings at the end of
bronchioles is called alveoli
 They have a thin wall specialized for diffusion of
gases between the alveolus and the blood in the
pulmonary capillaries
 Gas exchange can take place
in the respiratory bronchioles
and alveolar ducts as well as
in the alveoli

38. Respiratory System
Alveoli
 Each lung contains approximately 300 to 400 million
alveoli
 The spongy nature of the lung is due to the packing of
millions of alveoli together
 simple Squamous cells of capillaries
 Functional unit of lungs
 Site of gas exchange of lungs
 about .5 μ in thickness

39. Respiratory System
Alveoli
 Tiny, thin-walled, grapelike clusters at the end of each
bronchiole
 Surrounded by capillaries
 Where carbon dioxide and oxygen
exchange take place
 Singular - alveolus

40. Respiratory System

41. Respiratory System
Respiratory System
Supporting System
• Pleura
• Diaphragm

42. Respiratory System
Pleura and Pleural Cavities
 Membrane lining between the lungs and chest cavity
 The double membrane layer of pleura creates a lining
between the lung and ribcage.
 The Parietal Lining (outer lining) is between ribcage
and lung.
 The Visceral Lining (inner lining) covers the lungs and
adjoining structures.
 The Pleural Cavity is space
between the 2 layers of Lining,
filled by pleural fluid

43. Respiratory System
Function of Pleura
 To reduce friction during breathing, by
acting as a lubricant
 No connection between the left and
right pleura, to prevent
 Surface tension increase of pleural fluid
increases tension on lungs and assists
in alveolar respiration e.g. in heavy
breathing

44. Respiratory System
Diaphragm
 Thin muscle wall between the chest and the abdomen
 It separates the thoracic cavity
(heart, lungs & ribs) from the abdominal
cavity
 An important function in respiration:
as the diaphragm contracts, the volume
of the thoracic cavity increases and air
is drawn into the lungs

45. Respiratory System
Muscles that ASSIST with respiration
 The scalenes help increase thoracic cavity dimensions
by elevating the first and second ribs during forced
inhalation.
 The ribs elevate upon contraction of the external
intercostals, thereby increasing the transverse
dimensions of the thoracic cavity during inhalation.
 Contraction of the internal intercostals depresses the
ribs, but this only occurs during forced exhalation.
 Normal exhalation requires no active muscular effort.

46. Respiratory System
Muscles that ASSIST with respiration
 Other accessory muscles assist with respiratory
activities
 The pectoralis minor, serratus anterior, and
sternocleidomastoid help with forced inhalation
 while the abdominal muscles (external and internal
obliques, transversus abdominis, and rectus
abdominis) assist in active exhalation.

47. Respiratory System

48. Respiratory System
Boyle’s Law
 The pressure of a gas decreases if the volume of the
container increases, and vice versa.
 When the volume of the thoracic cavity increases
during inhalation, the air flows into the lungs through
the conducting airways. Air flows into the lungs from a
region of higher pressure (the atmosphere)into a region
of lower pressure (the intrapulmonary region).
 When the volume of the thoracic cavity decreases
during exhalation, it forces air out of the lungs into
the atmosphere

49. Respiratory System
Respiratory System
Diseases of the
Respiratory System

50. Respiratory System
Diseases of Respiratory System
Upper Respiratory Tract (URTI)
1. Sinusitis
2. Laryngitis
3. Pharyngitis
Lower Respiratory Tract (LRTI)
1. Chronic Obstructive Pulmonary Diseases(COPD)
1. a- Chronic Bronchitis
2. b- Emphysema
2. Bronchitis
3. Pneumonia
4. Asthma

51. Respiratory System
Common Causes of Various Respiratory Diseases by Location
Disease Location Disease Group of Pathogen Comments
Upper respiratory tract
Most common cause
Nasal passages Common cold Viruses
rhinovirus
Viruses are most
Viruses
Nasal sinuses Rhinosinusitis common cause of
Bacteria
rhinosinusitis
Viruses Streptococcus
pyogenes and Viruses cause 90% of
Pharynx Pharyngitis
Corynebacterium these infections
diphtheriae
Respiratory airways
Usually Haemophilus
Epiglottis Epiglottitis Bacteria
influenzae type b
Bronchitis,
Usually caused by
Trachea and bronchi Tracheobronchitis, Viruses
viruses
croup, laryngitis
Most common cause is
Bronchioles Bronchiolitis Viruses respiratory syncytial
virus
Lower respiratory tract
Most common cause in
Alveoli and alveolar
Pneumonia Bacteria adults is Streptococcus
sacs
pneumoniae

52. Respiratory System
URTI
 Sinusitis
 Inflammation Of Sinuses
 Cause
 Viral/Bacterial/Fungal Infection
 Often Associated With URTI
 Symptoms
 Headache, facial pain, nasal discharge, fever and
cough
 Management
 Pain Killers/Anti-Pyretics
 Antibiotics 52

53. Respiratory System
URTI
 Laryngitis
 Inflammation Of The Larynx
 Causes
 Viral Or Bacterial Infections, Physical And
Chemical Stimuli, Excess Smoking Or Straining Of
Vocal Cords (speakers/singers)
 Symptoms
 Dry And Sore Throat, Cough, difficulty Swallowing,
sensation Of Swelling In The Area Of Larynx,
hoarseness
 Management 53
 Treat The Cause

54. Respiratory System
URTI
 Pharyngitis
 Inflammation Of Throat / Pharynx / Tonsils
 Causes
 Viral(40-60%), bacterial(group A Streptococci),
Fungal, Allergy and Trauma
 Symptoms
 Sore Throat, difficulty In Swallowing Or speaking,
headache and fever
 Management
 Treat The Cause
54

55. Respiratory System
LRTI
 Chronic Obstructive Pulmonary Diseases
 It makes breathing difficult. There are two types of
COPD:
 Chronic bronchitis- A long-term cough with mucus
 Emphysema- Involves destruction of the lungs over time
 Causes
 Smoking is the leading cause of COPD.
 Symptoms
 Cough, with or without mucus
 Fatigue
 Many respiratory infections
55

56. Respiratory System
LRTI
 Emphysema (COPD)
 Characterized by loss of elasticity of lung tissue
caused by destruction of structures feeding the
alveoli.
 Causes
 Smoking is the leading cause of COPD.
 Symptoms
 Shortness of breath that gets worse with mild
activity
 Trouble catching one's breath
 Wheezing
56

57. Respiratory System
LRTI
 Bronchitis:
 An inflammation of air passages within lungs. It
occurs when trachea & large and small bronchi
within the lungs become inflamed. It can be acute
or chronic.
 Acute Bronchitis:
 Can be viral/bacterial. Usually preceded by a
common cold or flu
 Chronic Bronchitis
 Prolonged irritation of bronchi like inhaling fumes,
dust or smoke with a persistent productive cough 57

58. Respiratory System
LRTI
 Pneumonia
 An inflammatory illness of lungs. Also described as
lung parenchyma inflammation with abnormal
alveolar filling of fluid
 Causes
 Bacterial/viral/fungal/parasitic infections
 Any physical or chemical injury to the lungs.
 Symptoms
 Productive cough, difficulty in breathing, fever &
chest pain.
58

59. Respiratory System
Lower Respiratory Tract Infections
 Asthma
 Is a common disorder of airways that is complex &
has variable symptoms which are airflow
obstruction, bronchial hyper responsiveness
(bronchospasm) and inflammation of the airways.
 Causes:
 environmental & genetic factors
 Symptoms:
 night time coughing, shortness of breath with
exertion and tight feeling in the chest
59

60. Respiratory System
Common Problems
 Coughing & Sneezing
 Cold
 Flu
60

61. Respiratory System
What is a cough?
Cough
A sudden defense reflex which helps to clear the
breathing passage from excess secretions or irritants
Types of Cough
Acute cough. Present for less than 3 weeks. Does not
produce any mucous or phlegm
Chronic cough. Present for more than 3 weeks,
produce phlegm or mucous from the lungs. Mostly
occurs due to viral or bacterial infections.
Cough in common cold
Two phase, first a non-productive and second
productive cough.

62. Respiratory System
62

63. Respiratory System
What is a Cold ?
COLD
 It's called common cold
 It's the most frequent infection across the worldand
all age groups
 Most adults have 2-4 colds per year and children have
3 to 8 per year
What Causes It?
 There are approximately 200 viruses that can cause a
common cold
 Rhinoviruses are responsible for up to half of all colds
63

64. Respiratory System
What Is Flu (Influenza)?
FLU
• Influenza (flu) is an illness caused by a virus that
comes on suddenly, and causes symptoms such as
fever, body aches, headache, fatigue, loss of appetite,
cough and a sore throat.
What Causes It?
• Health professionals classify the virus as influenza
type A and type B, each of which includes several
subtypes or strains
• These strains are different from the original virus but
retain some of its characteristics
• Type A is usually responsible for the annual
outbreaks that typically occur in the late fall and
early winter. 64

65. Respiratory System
SYMPTOMS COLD FLU
High (100 to 102 F:
Fever Rare especially in young children)
Lasts 3 to 4 days
Headache Rare Common
General Aches, Pains Slight Often
Fatigue, Weakness Sometime Usual can last upto 3 weeks
Usually at the beginning of
Extreme Exhaustion Never
the illness
Stuffy Nose Common Sometimes
Sneezing Usual Sometimes
Sore throat Common Sometimes
Chest Discomfort, Cough Mild to moderate Common can become severe
65

66. Respiratory System
COLD FLU
Antihistamines, Antiviral medicines,
Decongestant, Herbal
Treatment Nonsteroidal anti-
inflammatory medicines,
Herbal
Wash your hands often, Annual vaccinations;
Prevention Avoid close contact with antiviral medicines
anyone with a cold
Sinus congestion Middle Bronchitis, Pneumonia
Complications ear infections, Asthma can be life threatening
66

67. Respiratory System

68. Respiratory System
Genius is 1% Inspiration
And 99% Respiration