clinical anatomy of lungs

1. Clinical Anatomy of lungs
Dr. Ashish kumar
Dept. of Chest & T.B, Santosh university

2. Points
1. Basic anatomy
2. Surface anatomy
3. Blood circulations
4. Innervations
5. Lymphatic

3. Respiratory System starts at the nares
Major Functions
Upper respiratory system:
1. Air conditioning (warming)
2. Defense against pathogens
3. Gas Transport
Lower respiratory system:
1. Speech & other
respiratory sounds
2. Gas exchange (ventilation)
3. Maintenance of
homeostasis, e.g. pH

4. Respiratory Muscles
Diaphragm: depresses on contraction 
inhalation
External intercostals: elevate ribs  inhalation
Internal intercostals: depress ribs  active
exhalation
(Accessory muscles - serratus anterior, scalenes, pectoralis
minor, sternocleidomastoid, internal and external obliques,
transverse abdominus, rectus abdominus)

9. Upper Respiratory System
1. Nose
2. Nasal Cavity
3. Paranasal sinuses
4. Pharynx

10. Upper Respiratory
System
1) Nose
 External and internal nares =
Nostrils
 Nose Hairs = vibrissae
 Alar cartilages on the nose
 Paranasal Sinuses

11. Upper Respiratory
System
• 2) Nasal Cavity
• Nasal Conchae:
– Superior, middle and
inferior
– Other name: “Turbinate
bones” because they
create

12. Upper Respiratory
System
3)Paranasal Sinuses
• Named after their
bones
– Frontal
– Ethmoid
– Sphenoid
– Maxillary

13. Upper Respiratory
System
4) Pharynx
Shared passageway for respiratory and digestive systems
Nasopharynx - part above uvula and posterior to internal
nares
Oropharynx – portion visible in mirror when mouth is wide
open
fauces = the opening
uvula - posterior edge of soft palate
Laryngopharynx – between the hyoid bone & the esophagus

15. Larynx (voice box)
 The larynx consists of three
articulating cartilages,
1. Thyroid
2. cricoid
3. Arytenoid

16. Lungs
 Light, soft, spongy
 Conical in shape, apex, base, costal surface, medial
surface, hilus. Note various impressions
 Right lung
 Three lobes; superior, middle and inferior
 Oblique and horizontal fissure
 Left Lung
 Two lobes; superior and inferior also Lingula and Cardiac
notch, oblique fissure

17. Right Lung

18. Left Lung

19. Right Lung

20. Lung Fissures:
Oblique fissure (Right & Left):
It starts at the 3rd thoracic spine while the arms are elevated,
descends downwards, laterally & anteriorly along the medial
border of the scapula touching the inferior angle of the
scapula) cutting the midaxillary line in the 5th rib & ending at
the 6th costal cartilage 3 inches from the midline.
In cadaver it arise at the 2nd thoracic spine.
The transverse fissure (Right):
It arises at the 4th costal cartilage, runs horizontally to meet
the oblique fissure in the midaxillary line in the 5th rib.

21. Fissures & Lobes of the Lungs

22. Fissures & Lobes of the Right Lung

23. Right Upper Lobe

24. Right Middle Lobe

25. Right Lower lobe

26. Left Lung

27. Fissures of the Left Lung

28. Left Upper Lobe

29. Left Lower Lobe

30. Airways
 Trachea, primary bronchi, secondary bronchi, tertiary
bronchi out to 25 generations
 All comprised of hyaline cartilage
 Trachea
 Begins where larynx ends (about C6)
 10 cm long, half in neck, half in mediastinum
 20 U-Shaped rings of hyaline cartilage – keeps lumen intact
but not as brittle as bone
 Lined with epithelium and cilia which work to keep foreign
bodies/irritants away from lungs

31. From Bronchi to Lungs: The Bronchial
Tree
 1 bronchi (enter lungs at
hilus, complete cartilage
rings)
 2 bronchi (from now on
cartilage plates)
 3 bronchi
 Bronchioles
 Terminal bronchioles
 Respiratory bronchioles
 Alveolar ducts
 Alveolar sacs
Conducting
portion
Respiratory portion

32. Airways
 Primary Brochi One to each lung – continuation of
trachea
 Right bronchus is wider and shorter 2.5 cm as opposed to
5 cm and branches from the trachea at a greater angle
 Secondary bronchi – one to each lobe, three in right,
two in left
 Tertiary – one to each bronchopulmonary segment –
approximately 10 per lung
 All of the above are hyaline cartilage with no ability
to change diameter

35. Bronchopulmonary Segments

36. Bronchopulmonary Segments

37. Bronchopulmonary Segments

38. Bronchioles
 First level of airway surrounded by smooth
muscle (not the cartilage ), therefore can
change diameter as in brocho-constriction and
broncho-dilation
 Terminal
 Respiratory
 3-8 orders
 alveoli

39. Bronchioles

40. Surface Anatomy

41. Borders of the lung:
 The apex is about 2-3 cms (1 inch) above the medial
1/3 of the clavicle, then the anterior border of both
lungs run downwards & medially meeting each other
in the middle line behind the angle of Louis (sternal
angle).
 The anterior border of right lung continues running
downwards till the 6th costochondral junction.
 The anterior border of left lung continues running
downwards till the 4th costal cartilage then curves
laterally ½ inch forming the cardiac notch then
descends downwards till the 6th costochondral
junction.

42. Borders of the lung:
The lower border of the lungs represented by a line
starting from 6th rib in the MCL, 8th rib in the MAL &
10th rib in the scapular line.

43. Circulation of lungs
Two types
1. Bronchial circulation
2. Pulmonary circulation

44. Bronchial circulation
• The trachea (and esophagus), main-stem bronchi, and
pulmonary vessels into the lung , as well as the visceral
pleura in humans are supplied by the bronchial
(systemic) circulation.
• The bronchial circulation has enormous growth
potential. In long-standing inflammatory and
proliferative diseases, such as bronchiectasis or
carcinoma, bronchial blood flow may be greatly
increased.

45. Pulmonary circulation
• In humans the pulmonary artery enters each lung at
the hilum in a loose connective tissue sheath adjacent
to the main bronchus.
• The pulmonary artery travels adjacent to and branches
with each airway generation down to the level of the
respiratory bronchiole.
• As blood enters the vast alveolar wall capillary
network, its velocity slows, averaging approximately
1000 µm/sec (or 1 mm/sec),where gas exchange take
place.

46. • Anatomically, the pulmonary blood vessels can be
divided into two groups in
1. Extra-alveolar
2. Alveolar.
 Extra-alveolar
vessels lie in the loose-binding connective tissue
(peribronchovascular sheaths, interlobular septa).
Extra-alveolar vessels extend into the terminal
respiratory units. Arteries as small as 100 µm in
diameter have loose connective tissue sheaths. This is
in contrast to the bronchioles, which are tightly
embedded in the lung framework from the
bronchioles (1 mm in diameter) onward.
 Alveolar vessels
lie within the alveolar walls and are embedded in the
parenchymal connective tissue

47. Innervation
 Pleura via intercostal (thoracic) nerves.
 Tracheobronchial tree motor pathway
 Parasympathetic via CN X efferent function =
broncho-constriction via smooth muscle, also to
epithelial cells in trachea, afferent = responsible for
cough reflex
 Sympathetic from T1-T5 efferent = brocho-dilation

48. • Cholinergic, adrenergic, and peptidergic nerve
Endings are present around tracheal glands and do
not show patterns of slective innervation density
between serous and mucous cells . Serous and
mucous granule secretion is stimulated more by
muscarinic than by adrenergic agents.

49. lymphatics
• Superficial plexuses- The superficial plexus is located
n the surface of the lung just beneath the pulmonary
pleura.
• Deep plexuses-accompanies the branches of the
pulmonary vessels and ramifications of bronchi.

50. Right lung lymphatics
• Right upper lobe:
• Upper 2/3rd-Right tracheobronchial nodes
• Lower l/3rd -Dorsolateral hilar nodes
• Right middle lobe:
• Hilar nodes around middle lobe bronchus
• Right lower lobe:
• Porsolateral part-Dorsolateral hilar nodes
• Ventromedial part- Ventromedial hilar and carinal
nodes

51. Left lungs lymphatics
• Left upper lobe:
• Apex-para-aortic node
• Other than apex-Anterior and posterior hilar nodes
• Left lower lobe
• Dorsolateral part-Dorsolateral hilar nodes
• Ventromedial par^Ventromedial hilar and carinal
nodes